370 FXUS63 KDDC 181604 AFDDDC Area Forecast Discussion National Weather Service Dodge City KS 1104 AM CDT Mon May 18 2026 .KEY MESSAGES... - Very windy conditions will return to southwest Kansas on Monday, with wind gusts up to 50 mph potentially causing reduced visibility due to blowing dust. - Critical to Extreme Fire Weather is expected Monday afternoon across extreme southwest Kansas (west of Highway 283 and south of a Syracuse to Garden City line). In this area wind gusts of 40 to 50 mph and relative humidity near 5% will be possible. - Severe thunderstorms are possible Monday afternoon east of Highway 283. The primary threats are very large hail and damaging winds, with a few tornadoes also possible. - Models show an improving chance for precipitation across all of southwest Kansas by the middle of next week. && .DISCUSSION... Issued at 1158 PM CDT Sun May 17 2026 Models this evening are in good agreement in the evolution of the upper level trough over the Four Corners region over the next 24 hours. They also all are in good agreement with a shortwave trough/500mb jet max ejecting northeastward from the base of the trough towards western Kansas during the day on Monday. This will result in a deepening surface low over eastern Colorado, significantly tightening the surface pressure gradient across southwest Kansas as it lifts a surface boundary back north across southwest Kansas during the day. This setup combined with 850 mb winds increasing to 30 knots after 18z suggests that the NBM may end up being a little low on afternoon wind gusts given the past few days but if you lean towards the more realistic 75th percent (based on BUFR soundings wind gusts via momentum transfer). This would result in a few gusts approaching 50 mph which is well below high wind warning but strong enough to produce areas of blowing dust in locations that did receive rainfall from the storms Sunday night. The models today places this northward moving surface boundary near Garden City and Larned by mid afternoon with a dryline extending south of this boundary into western Oklahoma. East of the dryline the southerly low level flow will maintain dewpoints above 60 degrees. Also improve mid level instability and synoptic lift are expected during the afternoon as an upper level trough approaches from the west. This will result in another chance for strong to severe thunderstorms late Monday afternoon and evening across Central and South Central Kansas. Any storms that develop have a high probability of becoming severe, with the primary hazards being very large hail and damaging wind gusts. A risk for tornadoes also exists, with the most favorable area located across South Central Kansas where model guidance shows the dryline/cold front intersection coinciding with a developing low level jet early Monday evening. In addition to the severe weather threat...a critical to extreme fire weather risk is expected on Monday afternoon with the highest fire risk being confined to areas west of the dryline, where gusty southwesterly winds will align with a much drier airmass. Deep vertical mixing will not only transport high momentum winds down to the surface but will also draw down dry air aloft, causing afternoon relative humidity values to bottom out in the single digits. The combination of frequent gusts above 40 mph and extreme low level dryness will create a highly volatile environment favorable for extreme fire behavior and rapid rates of spread. Current Red Flag Warning has this area outlined very well. This first upper level trough will lift northeast toward the Upper Mississippi Valley Monday night, allowing the cold front to push south into Oklahoma. By Tuesday morning, this boundary is forecast to stall from southeast Colorado into western Oklahoma and remain nearly stationary through the middle of the week as a secondary upper level disturbance approaches from the west. Although specific details remain unclear, ensemble guidance suggests the mid week period may present multiple opportunities for accumulating rainfall across southwest Kansas. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 1100 AM CDT Mon May 18 2026 IFR cigs are expected to linger in vicinity of KHYS through mid- afternoon as prevailing low level stratus continues to erode slowly northward, then return to VFR the remainder of the afternoon as the stratus scatters out. Otherwise, primarily VFR conditions will persist in vicinity of KLBL, KDDC, and KGCK through early Tuesday. Thunderstorm development is likely along and ahead of a warm front projected to advance northward across south central Kansas late this afternoon through early evening. However, storms are expected to remain east of a KHYS to KDDC line. Light north-northeast winds will persist across west central and portions of southwest Kansas north of a quasi-stationary frontal boundary extending from the eastern Texas Panhandle northeast into south central Kansas. Meanwhile, southerly winds around 15 to 25kt with gusts up to 35kt will continue across south central Kansas into eastern portions of southwest Kansas south of the boundary through early evening. North winds around 15 to 25kt with gusts up to 30kt are forecast to develop generally after 23-01Z behind a cold front pushing southward through western Kansas this evening. && .FIRE WEATHER... Issued at 1158 PM CDT Sun May 17 2026 A critical to extreme fire weather risk is expected across southwest Kansas Monday afternoon. Ensembles earlier this evening agree that the dryline will be located near or just east of Highway 283 which will result in keeping the unseasonably dry air mass over extreme southwest Kansas (Cimarron Grassland). By late morning the stronger boundary layer winds will mix down to the surface, bringing gusts over 30 mph before noon and exceeding 40 mph by 2 PM. This deep mixing will also pull exceptionally dry air to the ground, dropping relative humidity into the single digits. These conditions will create a volatile environment west of Highway 283 and south of Garden City, where Red Flag Warning conditions are most likely. && .DDC WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 9 PM CDT this evening for KSZ074>078- 084>088. && $$ DISCUSSION...Burgert AVIATION...JJohnson FIRE WEATHER...Burgert  552 FXUS63 KAPX 181608 AFDAPX Area Forecast Discussion National Weather Service Gaylord MI 1208 PM EDT Mon May 18 2026 .KEY MESSAGES... - Slight risk for severe thunderstorms this afternoon. - Marginal risk for severe thunderstorms on Tuesday. - Sharply cooler weather arrives Wednesday and Thursday, with frost/freeze concerns Tuesday night through Thursday night (especially on Wednesday night). && .DISCUSSION... Issued at 1207 PM EDT Mon May 18 2026 Pattern Synopsis/Forecast: Moisture rich warm sector spreading northeast across the Great Lakes this afternoon as deep layer southwest flow continues between southeast Conus ridging and deep troughing rotating across the Intermountain West. Showers and thunderstorms beginning to percolate across northern Lake Michigan along decaying cold pool convergence (from overnight convection to our west). Surface based warming and attendant northward expansion of over 500 joules/kg of mixed layer cape within marginally supportive convective layer shear should continue to allow intensification of this activity as it races east across our area. Deep upstream troughing will continue to lift northeast, steadily shearing out as it crosses into southern Canada and the northern Great Lakes later Tuesday into Tuesday night. Attendant cold front expected to cross our area on Tuesday, with additional showers and storms expected to fire in the pre-frontal warm sector until its crossing. Sharply cooler airmass follows this passing wave, setting the stage for additional frost/freeze concerns for the middle of the week. Primary Forecast Concerns: Shower/storm evolution and severe potential through Tuesday. Secondary focus on just how cold we become through the middle of the week (those frost/freeze concerns). Details: Expect upscale growth to convective activity as it quickly slides northeast across our area the remainder of this afternoon. Combination of instability, those marginal convective layer shear profiles, and expected congealing cold pool dynamics should support some isolated severe potential, with gusty winds and marginally severe size hail the primary concerns. However, slightly backed low level wind fields down near Saginaw Bay will also support a very low risk for tornadoes as well. Loss of surface based instability should end the most aggressive shower/storm concerns quicky early this evening. Focus for most numerous storms and greatest severe potential focuses off to our west tonight in vicinity of primary wave and attendant east advancing cold front. May see some of this decaying activity slide into our area later tonight/early Tuesday morning. Not expecting anything too significant with this activity as surface rooted instability core is lost by then. Cold front will work steadily east across our area on Tuesday...exiting off to our east by early Tuesday evening. Front becomes increasingly detached from any large scale support, though moisture rich pre-frontal environment and forced low level convergence will continue to support shower and storm generation. Severe potential tied to just how much heating/surface rooted instability generation can occur prior to frontal passage. Think ongoing showers and cloud cover may limit this potential, with focus for severe storms centering to our south and southeast. SPC maintains just marginal severe weather potential across northern lower Michigan...themselves focusing on pre-frontal destabilization concerns. Focus quickly shifts to the arrival of a much cooler airmass as Canada originated high pressure drops into the western Great Lakes Tuesday night into Wednesday. Simple breadth of cold air advection looks to drop temperatures down into the 30s across a good portion of the area Tuesday night, although maintenance of gustynorthwest winds will likely prevent much freeze or frost concerns. A chilly Wednesday...when some areas will likely not get out of the 40s...gives way to what is shaping up to be a cold Wednesday night. Pattern recognition definitely supports such, with high pressure centering directly overhead supplying what should be clear skies and light/calm winds...all within an already exceptionally chilly airmass. Widespread lows well down into the lower and middle 30s looks easily attainable, and fully believe some of our traditional colder interior areas will make a run into the 20s. Definitely something to monitor given our recent warm temperatures. Conditions modify some Thursday and Thursday night, but could still see more frost and potential freeze concerns early Friday morning. Current trends support slow moderation through the weekend, with readings at least approaching more normal levels on Sunday. Other than the chill, extended period looks far less active, with perhaps some better rain chances returning during the weekend. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 618 AM EDT Mon May 18 2026 Low cloud deck with LIFR CIGs will likely hang around for a few more hours across parts of far northern lower and eastern upper -- sticking around the longest across areas north of the bridge. Daytime heating will help mixing and improve flight conditions with time. Scattered showers and storms are expected to form early this afternoon and track across most of northern Michigan. Current confidence is that these storms will from close to/just east of northwest lower TAF sites (MBL, TVC, PLN) and track east this afternoon and early evening, potentially impacting APN. Thunderstorm chances will end this evening with rain-free weather expected tonight. Winds will increase out of the southwest this morning with sustained winds around 10-15 kts and gusts to 20-30 kts at times into this evening. IFR/LIFR CIGs look to return to parts of northern Michigan later tonight. && .APX WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...Small Craft Advisory from 8 AM Tuesday to midnight EDT Tuesday night for LHZ345>349. Small Craft Advisory until midnight EDT Tuesday night for LMZ323-341-342-344>346. Small Craft Advisory from 8 AM Tuesday to midnight EDT Tuesday night for LSZ321-322. && $$ DISCUSSION...MSB AVIATION...DJC  665 FXUS66 KSEW 181609 AFDSEW Area Forecast Discussion National Weather Service Seattle WA 909 AM PDT Mon May 18 2026 .SYNOPSIS... High pressure will remain situated offshore through much of next week, maintaining near-normal temperatures across western Washington with cloudy mornings and sunshine in the afternoons. A few weak systems will move over the top of the ridge towards the middle of next week, bringing little more than a few periods of sprinkles. && .SHORT TERM /TODAY THROUGH WEDNESDAY/... Upper-troughing currently over the Great Basin while an upper- level ridge is just offshore the PNW. High clouds are currently streaming in under northwest flow aloft. Stratus has been confined to west central Washington between the Kitsap Peninsula and into the South Sound with the edges beginning to erode away. This will give way to mainly just high clouds and some fair weather cumulus across the area this afternoon. High temperatures are forecast in the 60s across the interior with 50s along the coast. Increasing onshore flow will lead to breezy winds through the Strait of Juan de Fuca this evening with gusts up to 30 mph on Whidbey Island before gradually decreasing later tonight. HREF suggests a 35% chance of gusts exceeding 35 mph. Overnight lows will fall into the 40s. Upper-ridging is likely to maintain through midweek as conditions remain rather benign. Weak disturbances will attempt to traverse along the periphery of the ridge - maintaining slight (15% or less) PoPs but mostly for the mountains. Temperatures are to remain near-seasonal throughout this period with highs in the 60s to near lower 70s and lows in the 40s. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... The upper level ridge offshore will begin to flatten on Thursday as a low pressure system slowly strengthens and lowers from the Gulf of Alaska. Conditions are favored to remain dry into the first half of the weekend as zonal flow sets up aloft, with continued mild temperatures. Ensembles are honing in on a potential pattern change by the end of next weekend, with increasing chances for widespread rainfall arriving Sunday evening. However, the details remain uncertain at this time. 41 && .AVIATION... North/northwesterly winds will persist aloft as an upper level ridge remains nudged over the region. Onshore flow will continue in the low levels, which allowed for some localized stratus to push inland this morning, mainly for areas along the coast, the Southwest Interior, and the south Sound where these terminals are seeing MVFR/IFR conditions likely through 18z (most likely for KHQM, KPWT, and KOLM). Expect cigs at the remainder of the terminals to remain VFR through the day. Winds remain light southerly at 6 kt or less across the majority of the interior terminals this morning, outside of KPAE, where winds continue out of the north. Winds along the coast are light northwesterly and KCLM remains westerly between 8-12 kt under increased onshore flow. Winds will increase to 7-10 kt this afternoon and look to switch to the north across the interior between 00-03Z tonight. A weak, splitting frontal system will move into the area tonight into Tuesday, with the main impact being more widespread stratus by Tuesday morning. KSEA...MVFR ceilings this morning with broken clouds at the terminal around 1500 to 2000 ft. Ceilings will rebound to VFR likely after 17z and will remain VFR throughout the day. A much greater probability (40-45 percent) exists of ceilings dropping to MVFR by Tuesday morning. Winds are southerly and will increase to 7-10 kt this afternoon, before switching to the north between 00-03Z. 14/Mazurkiewicz && .MARINE... High pressure will remain situated over the northeastern Pacific through much week, bringing a prolonged period of north/northwesterly winds to the coastal waters. A weak, splitting frontal system will move into the waters tonight into Tuesday and will bring an increase of onshore flow along the central and eastern Strait of Juan de Fuca, with another round of small craft westerlies expected this afternoon and evening. High pressure will build back into the coastal waters in the wake of the front. Onshore flow will persist throughout much of the week and will result in daily pushes of westerly winds along the Strait. The next weak frontal system looks to move into the area waters Thursday into Friday, followed by another late next weekend. Seas will generally hover between 6-8 ft through the first half of the week, before increasing towards 8-10 ft mid to late week. The latest GEFS probabilistic guidance is highlighting roughly a 20-40 percent chance of seas exceeding 9 ft by next weekend. 14 && .HYDROLOGY... The daily hydrology discussion has ended until the start of the next rainy season; it will only be updated during this time as needed. && .SEW WATCHES/WARNINGS/ADVISORIES... WA...None. PZ...Small Craft Advisory from 2 PM this afternoon to 5 AM PDT Tuesday for Central U.S. Waters Strait Of Juan De Fuca- East Entrance U.S. Waters Strait Of Juan De Fuca. && $$  132 FXUS64 KOHX 181618 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 1118 AM CDT Mon May 18 2026 ...New SHORT TERM, LONG TERM... .KEY MESSAGES... Updated at 1118 AM CDT Mon May 18 2026 - Above normal temperatures in the upper-80s to low-90s continue through Tuesday. - There is a high chance for showers and storms Tuesday night into Wednesday. The severe threat is very low. - Additional rain chances late week may push rainfall totals over 2 inches by the end of the week. && .SHORT TERM... (Rest of today through Tuesday) Issued at 1118 AM CDT Mon May 18 2026 Not much in terms of cloud cover over Middle Tennessee currently, but clouds are approaching from the west and the south this afternoon. We're already in the 80s in a lot of areas across Middle Tennessee, with highs expected to top out in the low 90s. We could possibly see a stray shower or thunderstorm from the convection to our north and west this evening, but that probability is very low at this time. Tuesday will be the start of a pattern shift in the area. Through the end of the week, Middle Tennessee will be stuck in a troughing pattern with several systems coming through. The good news is it looks to bring some much needed rainfall to our yards, with QPF through the end of the forecast period around 1.5 to 2.3 inches. The bad news is there is a severe threat associated with a cold front Tuesday afternoon into Wednesday morning. The severe threat is a marginal risk, level 1 out of 5, but not impressive. Any severe weather we get in Middle Tennessee with this will be pretty isolated, as the better parameters for more widespread severe are displaced to our northwest again. Despite cloud cover, southerly flow will raise our temperatures into the 90s once again for highs on Tuesday before the cold front swings through. && .LONG TERM... (Tuesday Night through next Monday) Issued at 1118 AM CDT Mon May 18 2026 Our unsettled weather continues mid-week, with our highest rain chances Wednesday. As the cold front passes through and high pressure sets up to the north, expect rainy conditions all day on Wednesday. While it will be a soaker, severe weather is not a concern at this time. The cold front will slowly pass through Middle Tennessee into Wednesday night, and is expected to stall out just to our south in northern Mississippi and Alabama. This will lead to another higher rain chance south of I-40 Thursday afternoon and evening. PWATs will remain on the higher side through the forecast period, and probabilities of greater than 2 inches of rain by the end of the weekend are still around that 50-70% range. We will continue to cross our fingers and hope the rain totals don't decrease! Temperatures will drop a little after the front to the upper 70s and low 80s, but that's about it for the remainder of the forecast period. && .AVIATION... (12Z TAFS) Issued at 516 AM CDT Mon May 18 2026 VFR will continue through this TAF cycle. South winds will be light at night and gusty to 20-25 KTS daytime. && .PRELIMINARY POINT TEMPS/POPS... Nashville 92 71 91 67 / 0 10 20 60 Clarksville 90 72 90 66 / 10 0 40 80 Crossville 85 66 84 64 / 10 0 10 40 Columbia 90 70 90 66 / 0 10 20 50 Cookeville 88 69 87 66 / 0 0 10 40 Jamestown 89 66 88 64 / 10 0 10 40 Lawrenceburg 88 70 87 67 / 0 10 10 60 Murfreesboro 91 71 90 67 / 0 10 10 60 Waverly 90 73 90 68 / 0 0 30 70 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Holley LONG TERM....Holley AVIATION.....13  190 FXUS61 KPBZ 181620 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 1220 PM EDT Mon May 18 2026 .WHAT HAS CHANGED... On the whole, the forecast remains unchanged, except for higher confidence in an 8p to 2a arrival of storms in northwest PA and eastern Ohio Tuesday night. && .KEY MESSAGES... 1) Heat impacts for sensitive populations continue early this week, with temperatures up to the upper-80s to low-90s. 2) Conditional terrain/lake driven severe chances today, highest severe chances tomorrow evening for NW PA and east OH, and conditional severe threats Wednesday SE of Pittsburgh with departing front. && .DISCUSSION... KEY MESSAGE 1... The 12Z surface analysis has the 587dm height line draped across the area, which generally suggests that upper 80s are most likely for highs today. A non-BC model like the LREF and HREF, generally agree, with the 25th-75th percentile spreads narrow and generally between 86F and 90F. With high confidence in mostly clear skies for most today, its possible these deterministic high tend toward the higher end of the non-BC distribution. So this would generally mean temperatures near-90, with some 90s possible with urban and river-valley terrain influence. Some "cooler spots" into the low-to-mid 80s are favored for high terrain and north of I-80. Highs today will be within a few degrees of record highs for all climate sites. The HREF only alludes to temperatures dropping into the mid-to- upper 60s, which will provide little chance for temperature recovery overnight. This will challenge a few "max-low temperature" records. Mean heights may drop slightly Tuesday with the beginning of a ridge breakdown. Additionally, more mid- moisture will also allow for more cloud cover. All in all, temperatures may be a degree or two cooler in areas that do not see rain, but cumulative heat stress continues. So upper-80s, are again favored for most. The NWS heat risk shows mostly a moderate risk Monday into Tuesday, whereby heat may generally impact the most sensitive populations. Make sure to stay hydrated or monitor for signs of heat illness if spending excessive time outdoors. KEY MESSAGE 2... All of the area will be under the northern periphery of the ridge axis today, with corresponding subsidence enforcing mid- level capping. While diurnal cumulus are developing, as we continue to mix into a dry layer (evidenced on 12Z sounding from 750mb to 600mb), we expect most vertical development to be limited. There's a couple exceptions that will need to be addressed. First will be the high terrain. With ridge-top convergence in mostly NE flow aloft, we coudn't rule out a storm firing in an environemnt of 1000-1200 DCAPE, which could certainty carry a conditional downburst wind threat in the low probability this happens. Consistently, the highest chance of development has been eastern Tucker County, but with NW flow aloft, the thought would be that the highest risk would be to the east for the forecast area. The second area would be a conditional threat of storm development on a lake breeze this afternoon. This is lower confidence, but should it occur, the same downburst threat is possible, with outflow potentially carrying development into NW Pennsylvania. Both threats are conditional on development (<30% chance), but should development occur, damaging wind risks would increase substantially. A ridge breakdown begins Tuesday, with afternoon storm development in western Ohio likely. The most likely timing of this appears late- day. There's a bit of a conditional risk from 20Z to 00Z, but the current thought is that capping will be too strong to let the environment utilize the ~1500 to 2500 MUCAPE for "bubble-up" convection in NW PA in the afternoon. Later, some combination of outflow from the Ohio convection on a pre-frontal trough and/or a lake breeze will make convection more likely in the 00Z to 06Z window. Since this timing is mostly after sunset, storms are expected to have a decaying trend as they enter the area, but they certainty could be strong enough to produce wind gusts up to 60mph, most likely for the I-80 corridor with DCAPE of 900 to 1000, with threats also possible into eastern Ohio. Convective intensity is expected to wain overnight as the parent cold front moves in, but some isolated showers/storms remain possible. Wednesday will bring more of a conditional severe threat southeast of Pittsburgh, with the main uncertainty being 1) frontal timing and 2) cloud cover. In a scenario with a slower front and limited cloud cover, recovery of instability and a limited severe threat is possible for northern WV and far SW PA. But should the front be faster or clouds complicate instability generation, severe threats are lower. Severe chances taper over the next week. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... High confidence VFR through the TAF period under the influence of high pressure east of the region. A few cu develops this afternoon with peak heating/mixing while southwest winds occasionally gust between 15-25kts (near 0% likelihood of exceeding 25kts). Any convective chances are tied to weak convergence along the WV ridgeline, with storms drift northeast, further cementing minimal terminal concerns. Nocturnal increases in the low-level jet may create brief periods of LLWS, but the lack of duration or meeting criteria (either by speed/direction or by height) led to an omission from TAFs. Area mid to high level cloud cover increases overnight into Tuesday morning in association with an eastward moving but decaying MCS. There is a non-zero chance for isolated showers and thunderstorms develop off its outflow near to after 00z around northwest PA but probability is too low for TAF mention. Outlook... Outside of an isolated afternoon thunderstorm Tuesday, VFR persists until an upper shortwave and surface front push a shower/thunderstorm axis east Tuesday evening through Wednesday afternoon. Initial restrictions will be tied to rainfall intensities with height falls not occurring until after frontal passage. High pressure and VFR returns by Thursday areawide before an active pattern feature multiple rain chances develops Friday into the weekend. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...Milcarek AVIATION...Frazier/Lupo  227 FXUS64 KTSA 181621 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 1121 AM CDT Mon May 18 2026 ...New SHORT TERM, LONG TERM... .KEY MESSAGES... Updated at 1119 AM CDT Mon May 18 2026 - Windy with isolated to scattered showers and storms through this evening. Limited severe risk. - Numerous showers and storms Tuesday morning into NE OK spreading southward through early afternoon. Severe weather possible along with locally heavy rainfall. - Cooler temperatures Wednesday-Friday with continued low rain chances through the remainder of the week. && .SHORT TERM... (Through tonight ) Issued at 1119 AM CDT Mon May 18 2026 Moist and unstable southerly flow remains in place across the area. Modest lift within the warm advection in the lower levels of the atmosphere is and will continue to result in isolated to scattered showers and storms the next few hours, particularly in far northeast OK and northwest AR. These storms will mostly stay sub severe, but some marginally severe hail is possible in the stronger storms. A few CAMs suggest storms could form along the dry line in western Oklahoma this afternoon, with storms then moving east into the forecast area, though this remains the less likely outcome. If these dry line storms did develop, these storms would have the potential to be severe. Otherwise, warm, humid, and windy conditions will persist through the day with highs reaching the mid to upper 80s. Near the tail end of the overnight hours a cold front will move into northeast OK. CAMs disagree on the storm details, but the most probable outcome is for a line of storms to be present along the front. Significant severe weather may occur north of the area, but the expectation is that the storms will be weakening at least somewhat as they approach the area. There are several reasons for this, including relatively weak upper level forcing and weak flow. Still, there will be a threat for strong damaging winds and an isolated tornadic spin up, particularly as storms first enter from Kansas. Areas of heavy rainfall may occur as the storms move through. && .LONG TERM... (Tomorrow through Monday) Issued at 1119 AM CDT Mon May 18 2026 Near dawn on Tuesday the line of storms will be moving through northeast OK, continuing southeast through the early afternoon before exiting the area. Wind shear will remain unimpressive, but there will be sufficient instability with daytime heating for a few storms to become severe. Large hail and strong gusty winds will be the main hazards, with a lesser tornado threat. Behind the cold front temperatures will quickly cool with much drier air. Most guidance is producing a renewal of showers and possibly a thunderstorm north of I-40 Tuesday evening. This will occur along an elevated frontal boundary remaining over the area. Wednesday will be cool and quiet outside of a few showers lingering for southeast OK and northwest AR. Highs will only reach the 70s Tuesday and Wednesday, perhaps even upper 60s in some spots. Lows will be in the lower 60s and upper 50s. A shortwave trough will dive into the area from the northwest Thursday to Friday, interacting with some remnant troughing across the desert Southwest. This will result in an increase in shower and thunderstorm activity across the area. With modest but sustained forcing, high PWAT, and a deep layer of minimal CAPE, this will be a good setup for several rounds of moderate rain, with only minimal severe weather risk. Over the weekend and into early next week it gets a little more uncertain, as models aren't confident on whether we get a short term break and warm up and dry out a bit, or if the remnant southwest troughing will keep shower activity going. Either way, if there is a break, it will be short lived with another storm cycle likely into the middle of next week. Overall, it appears somewhat cooler and wetter weather will be here to stay for a while. && .AVIATION... (12Z TAFS) Issued at 621 AM CDT Mon May 18 2026 Low clouds will continue to expand in coverage this morning, with MVFR cigs becoming increasingly common across E OK and NW AR. Scattered showers and thunderstorms will be possible through the morning and early afternoon hours across much of the area, particularly in SE OK and NW AR. Thunderstorm coverage remains uncertain, but a mix of PROB30 and TEMPO groups have been introduced for this potential. Ceilings are likely to improve back to VFR this afternoon as low clouds scatter out and lift. A lull in precipitation is expected late afternoon through evening before a line of storms moves south into the area from Kansas late overnight. Latest guidance suggest these storms will being to move into NE OK and NW AR sites by 08-12z. Widespread southerly LLWS develops this evening and continues through much of tonight. && .PRELIMINARY POINT TEMPS/POPS... TUL 87 67 75 58 / 50 60 70 80 FSM 89 72 84 65 / 40 10 90 70 MLC 88 73 82 61 / 20 10 100 70 BVO 87 61 71 53 / 20 80 40 60 FYV 85 72 80 60 / 40 20 90 80 BYV 85 72 81 59 / 30 20 90 90 MKO 86 71 78 59 / 40 20 90 70 MIO 85 67 74 56 / 60 60 80 70 F10 87 70 78 58 / 30 20 80 70 HHW 87 73 81 65 / 20 10 90 60 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...Wind Advisory until 9 PM CDT this evening for OKZ055>064-067-154- 254-354. AR...None. && $$ SHORT TERM...06 LONG TERM....06 AVIATION...43  719 FXUS64 KHUN 181634 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 1134 AM CDT Mon May 18 2026 ...New AVIATION... .KEY MESSAGES... Updated at 1030 AM CDT Mon May 18 2026 - Low chances (10%-20%) for showers across northeast Alabama today. - Low to medium chances (20-60%) for showers and thunderstorms returning late Tuesday, then medium to high chances (50-90%) for showers and thunderstorms each day, from Wednesday through the weekend && .NEAR TERM... (Rest of Today and Tonight) Issued at 1030 AM CDT Mon May 18 2026 Morning satellite imagery indicating mostly clear skies with scattered low/mid cloud cover passing through the Tennessee Valley. Temps are already pushing 80 degrees this morning with dew points in the mid/upper 60s. Highs will top out in the upper 80s to right around 90 degrees once again this afternoon with southerly winds of 10-15 mph gusting near 20 mph. Axis of slightly better moisture and instability (SBCAPE ~1000 J/kg) will remain east of I-65 this afternoon where there will be a 10-20 percent chance primarily for shower activity. A rumble of thunder is not out of the question but should be few and far between. Tonight...winds will drop off after sunset with lows remaining mild in the mid to upper 60s. && .SHORT TERM... (Tuesday through Thursday) Issued at 1030 AM CDT Mon May 18 2026 Mid-level ridge which has been in place to our east for several days will begin to weaken over the local area on Tuesday as a trough swings across the northern Plains and associated sfc low transitions northeastward across the Great Lakes region. The sfc cold front will push eastward throughout the day Tuesday approaching the local area late on Tuesday into Wednesday. It will slow and become near stationary over MS/AL/GA on Wednesday. As a result, chances for rain/storms will increase Tuesday night into Wednesday along and ahead of the frontal boundary with continued rounds of activity on Wednesday and Thursday as a series of shortwaves transition along the western edge of the subtropical ridge over the TN Valley as plenty of moisture remains in place along the stalled frontal boundary. Morning CAMs coming in are backing off significantly in precip chances with the initial precip coming in tomorrow night with the cold front. Any notable precip chance remain west of I-65 until after sunrise on Wednesday but that still may be too high if trends continue. Rain chances will peak Wednesday and Thursday during the daytime hours between 70%-90% both days. Shear profiles aren't impressive at this time and the severe threat remains low but will feel very summer like in terms of convection with sufficient instability, moisture, and lift in place to fuel these rounds of activity. We are included in a "Marginal" risk for Excessive Rainfall by WPC for Wednesday and Thursday but any rainfall will be beneficial at this point and QPF totals are not anticipated to result in any sort of impactful flooding outside of ponding on roadways where localized higher amounts are seen. High temps will remain above normal on Tuesday before moderating mid- week into the low/mid 80s under increased cloud cover and weakening ridge. && .LONG TERM... (Thursday night through Sunday) Issued at 1045 PM CDT Sun May 17 2026 This pattern will continue largely unabated from Thursday night into the weekend, with a broad summer-like subtropical ridge centered near Bermuda and deep SWRLY flow persisting across the TN Valley. A series of shortwaves are expected to ride along the trough/ridge interface across the region and bring bouts of increased shower/storm activity. Timing this is difficult, as the distinct nature of these shortwaves is difficult to discern in the model guidance. Nevertheless, increased instability during the daytime will certainly act to regulate chances for showers/storms during the period. Thermo profiles during the Thurs-Friday period do not appear to change significantly, with generally moist- adiabatic type profiles in the increasing deep/humid airmass. PWs climbing to near 1.7 inches and only modest CAPEs and weak-modest shear would suggest the largest threat may be due to any localized flash flooding that could result, especially with the prospect for slow-moving training storms. Shear may increase a little into the weekend, but still would characterize as modest at best. Overall, this is reminiscent of a warm, early summer pattern with highs mostly in the 80s and warm nights with lows in the 60s. && .AVIATION... (18Z TAFS) Issued at 1134 AM CDT Mon May 18 2026 VFR conditions are forecast to continue through the TAF period. Gusty southerly winds up to 20-25 knots can be expected this afternoon before subsiding around sunset tonight. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...KG SHORT TERM....KG LONG TERM....KDW AVIATION...GH  097 FXUS63 KIND 181645 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 1245 PM EDT Mon May 18 2026 .KEY MESSAGES... - Severe storms possible this afternoon and again Tuesday afternoon and evening with damaging winds, large hail and localized flooding - Highs in the 80s today and Tuesday - Storms will end Wednesday as the front shifts south, but unsettled weather likely returns late this week into the holiday weekend && .FORECAST UPDATE... Issued at 1014 AM EDT Mon May 18 2026 A line of thunderstorms continues to march east into central Illinois this morning, and scattered convection is developing ahead of this line with an area of additional lift. Temperatures across central Indiana were already in the upper 70s with dewpoints generally in the lower to middle 60s. Upper 60s dewpoints were in the far southwest and farther upstream to the southwest. Based on latest radar trends, sped up arrival of PoPs this morning into early afternoon. The newer convection leads to some increased uncertainty on how convection evolves this afternoon. Instability will continue to build, especially central and east before the clouds from upstream convection limit heating. The initial convection will be able to tap into this instability, but upstream convection may have less to work with. Either way, strong to severe convection remains a threat into the afternoon so will continue to mention. High temperatures may be optimistic west but for now will make no changes and continue to monitor. && .MESOSCALE UPDATE... Issued at 1244 PM EDT Mon May 18 2026 Thunderstorms are developing along the Indiana Illinois state line. These storms have been loosely organized so far, but an outflow boundary from convection further upstream is impinging from the west. This outflow boundary may allow storms to consolidate into a more coherent line as they progress deeper into Indiana. A recent sounding from Purdue University shows modest lapse rates between 6-7 C/Km, with a moist profile to about 500 mb. Additionally, modest shear is also present (20-25 knots) with messy hodographs centered around the mean storm motion. As such, little in the way of storm relative upper-level outflow appears likely...storms should behave more like single cells to multicell clusters until they become influenced by the outflow boundary or their own outflow. Once storms consolidate on the outflow boundary, they should still be relatively 'pulsey' in nature but more organized than in the open warm sector. The primary threat today appears to be strong wind gusts, as enough moisture loading within mature updrafts is possible for wet microbursts. Additionally, cold pool dynamics such as rear- inflow jet surges are also possible which may produce strong to damaging wind gusts. Given a mean shear vector towards the northeast, cold pools that orient in a NW to SE direction pose the greatest threat for severe wind gusts. Hail is possible but given only modest lapse rates, high moisture content, and the lack of long straight hodographs it does not appear to be all that likely. Tornado potential also appears low, given the outflow dominant nature of storms today. A brief QLCS spin up cannot be ruled out, however. Another threat, likely replacing wind as the primary hazard later this evening, is the potential for flooding and flash flooding. High- resolution guidance shows the cold pool settling in a SW to NE fashion across central Indiana. This may allow for repeated rounds of storms into tonight. As mentioned above, moisture content in the profile is high and freezing levels are near 15,000 feet. With a warm cloud layer over 10,000 feet in thickness, warm rain processes should lead to efficient rainfall production today. As such, various CAMs are showing pockets of very heavy rainfall totals between 3 to 5 inches. HREF ensemble mean shows a large area of 1 to 2 inches. Because of this potential, a Flood Watch has been issued for for western portions of the area. As cold pools become more defined, this may need to be trimmed or expanded. && .DISCUSSION (Today through Sunday)... Issued at 258 AM EDT Mon May 18 2026 An amplified upper level pattern for early this week anchored by a deep trough over the northern Rockies and strong ridging over the eastern part of the country. The ridge will gradually flatten as the trough shifts east enabling a strong cold front to track into the region by late Tuesday. With a warm and unstable airmass ahead of the front...multiple opportunities for thunderstorms will exist through Tuesday night with severe weather possible this afternoon and potentially again Tuesday afternoon and evening as the cold front moves through. High pressure will bring a briefly drier period midweek before unsettled conditions return late week in response to the front lifting back north into the region. Today through Tuesday Night Quiet early morning across central Indiana with clear skies. 06Z temperatures remained warm in the upper 60s and lower 70s in many locations. An active 48 hours is anticipated through Tuesday night with multiple opportunities for rain and thunderstorms and the potential for severe weather in advance of a cold front currently over the Plains and poised to move across the area by Tuesday evening. An ongoing area of convection continues early this morning from the upper Midwest southwest into central Kansas. Much of the line has weakened from Sunday evening with the exception of the southern part of the line over the Missouri Valley where instability and BL shear remain more than sufficient to maintain convective intensity. This portion of the line is likely to remain strong for the remainder of the night with an in creasing flood risk as it sags into south central Missouri and becomes increasingly parallel to the mean flow. The weaker portion of the line over Iowa is of greater interest to the forecast area as its remnants will enable the old outflow boundary to drift into central Illinois by mid to late morning with convection becoming reinvigorated as the outflow interacts with a rapidly destabilizing airmass over the region. Convection will continue to grow upscale as it tracks into the Wabash Valley early this afternoon then presses southeast across the forecast area. Model soundings show steepening mid level lapse rates with SBCAPEs 2000-2500 j/kg and sufficient shear that would support damaging winds...especially if the cold pool can mature. Furthermore...DCAPE values approach 1000 j/kg immediately ahead of the convective line which also lends credence to the damaging wind risk. Abundant CAPE is present within the hail growth zone as well and stronger cells will carry a large hail threat as well. Timing of the greatest risk for severe weather will be between 17Z and 22Z. Storms will weaken as they track towards the Indiana-Ohio border by early evening as it moves away from the deeper instability and stronger low level winds. An axis of PWATs between 1.75 and 2 inches will support torrential rainfall and flooding. The greatest concern will be across the southwest half of the forecast area as training cells become a factor with the line curving back to the west along the instability axis. Showers and embedded storms will continue into the evening but with the airmass worked over from the afternoon convection...the general trend will be towards rain diminishing as weak ridging aloft reestablishes for the overnight. Tuesday has become a bit more uncertain with respect to convective evolution and the potential for another round of severe weather as the model suite has sped up the arrival of the front into the forecast area in the afternoon. More impactful though will be the possibility of convective cloud debris by Tuesday morning from an MCS over the Missouri Valley Monday night. That will stunt diurnal heating and available instability and the earlier arrival of the front during the afternoon presents the possibility that the greater risk for more robust convection will focus across the southeast half of the forecast area and points east late afternoon into the evening. That being said...model soundings do continue to highlight mid level lapse rates up to 7.5C/km with a deep layer of dry adiabatic flow across the region combined with sufficient levels of BL shear to support scattered stronger convection at a minimum with the available instability. Damaging winds will again be the primary risk from these storms with large hail serving as a secondary threat. The cold front will become more parallel to the flow aloft on Tuesday night which will keep showers and thunderstorms across much of the forecast area into Tuesday night...gradually ending from the north overnight as drier air advects into the region. Highs will be tricky both today and Tuesday...dependent on convective timing this afternoon and cloud debris Tuesday. Nudged highs both days down from the model blend with low to mid 80s for much of the forecast area. Wednesday through Sunday Convection may still be ongoing across the southeast half of the forecast area Wednesday morning but will gradually end through the morning as the front shifts south of the region and high pressure builds into the Great Lakes. Confidence continues to grow on the boundary becomes quasi stationary across the Tennessee Valley into Thursday before lifting back north into the Ohio Valley Friday as the high passing to the north moves east into New England. The ensemble guidance has gotten more aggressive in this solution with scattered to numerous showers and storms Friday and Friday night as the front lifts north through the forecast area. Lower confidence remains for the weekend as the return of a warmer and more unstable airmass south of the front will support at least a daily threat for scattered convection but the lack of much agreement in the model ensemble makes employing detail in the timing and coverage of rainfall difficult through much of the holiday weekend. After temperatures mainly in the upper 60s and low 70s Wednesday and Thursday...highs will climb back into the upper 70s and lower 80s Saturday and Sunday. && .AVIATION (12Z TAF Issuance)... Issued at 609 AM EDT Mon May 18 2026 Impacts: - A line of severe thunderstorms expected to impact all terminals this afternoon with showers continuing into the evening - Peak wind gusts this afternoon at 25 to 30kts Discussion: Mainly sunny skies are expected to start but expect an increase in mid and high level clouds as the morning progresses associated with the remnant convective cluster extending from western Illinois back into Missouri. Storms should continue to weaken over the next few hours but the leftover outflow boundary is likely to serve as a focal point for renewed convective development by late morning across central and eastern Illinois as it interacts with an increasing unstable airmass. The line will move into the Wabash Valley early this afternoon then track across the terminals during the 17 to 22Z timeframe. Damaging winds will be a possibility along the leading edge of the convective line Restrictions to IFR and lower will accompany the line as well. Scattered convection should linger into the evening before gradually diminishing in coverage. Windy conditions will develop quickly after daybreak with peak gustsat 25 to 30kts prior to storms arriving in the afternoon. Gusts should drop off by early evening. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ MESOSCALE...Eckhoff UPDATE...50 AVIATION...Ryan DISCUSSION...Ryan