FXUS64 KHUN 190311 AFDHUN Area Forecast Discussion National Weather Service Huntsville AL 1011 PM CDT Mon May 18 2026 ...New NEAR TERM, SHORT TERM, LONG TERM... .KEY MESSAGES... Issued at 1010 PM CDT Mon May 18 2026 - Low to medium chances (30-60%) of showers and thunderstorms return late Tuesday. - Medium to high chances (50-90%) of showers and thunderstorms then persist each day from Wednesday through much of the weekend. No severe weather is forecast. && .NEAR TERM... (Rest of Tonight and Tuesday) Issued at 1010 PM CDT Mon May 18 2026 Currently watching as a few showers/storms, remnants of outflow boundaries to our south, move from central Alabama up into Cullman County. These may eventually progress into Morgan and Marshall counties late this evening if they hold together. Overall, not anticipating much out of this activity other than some light rainfall and perhaps some lightning (no severe weather). With the loss of daytime heating, these are forecast to gradually dissipate over the next hour or so, as has been the trend the last several radar scans. Otherwise, expect a warmer night as lows only decrease into the upper 60s to lower 70s (cooler over the higher terrain of northeast Alabama). Confidence is low in the occurrence any patchy fog development, with winds around 5 knots continuing overnight and clouds on the increase later tonight as well. Upper level southwest flow will continue on Tuesday, along with surface high pressure to the east over the Carolinas. Although, an cold front looks to progress over the mid-Mississippi River Valley by late afternoon. There are very low chances (less than 10%) of showers and storms over far northwest Alabama Tuesday afternoon. In fact, with the cold front expected to still be well to our west by late afternoon, most shower and storm activity should hold off until the evening. Therefore, partly cloudy skies will continue yet again tomorrow with warm temperatures - highs in the upper 80s to around 90 degrees! && .SHORT TERM... (Tuesday Night through Thursday Night) Issued at 1010 PM CDT Mon May 18 2026 Southwest flow will persist aloft through late week, with subtle shortwaves rippling along the flow during this time. In addition, the aforementioned surface cold front over the Mississippi River Valley will slowly progress southeast over the Tennessee Valley. This feature looks to then meander over the region for several days (through late week). This overall pattern will keep daily chances (50-90%) of showers and storms in the forecast from midweek into the weekend. To put the wet conditions into perspective, model PWATs generally range between 1.5-1.8 inches through the short term period. When compared with Sounding Climatology from Birmingham, these values are right around to just over the 90th percentile (1.6 inches) for May 20th and 21st. Therefore, showers and storms will be efficient rainfall producers. With daily rain chances through late week, we'll need to keep an eye on which areas receive rainfall and if it's repetitive, which would increase the localized flood risk. Currently, the Weather Prediction Center has most of north Alabama and southern middle Tennessee in a Marginal Risk (level 1/4) of excessive rainfall and this continues through late week. Remember, if you encounter flooded roads, Turn Around Don't Drown! As for the potential for any severe storms, while instability looks to be sufficient, confidence is low in the development of severe storms due to the continuing trend of low bulk shear values by guidance (especially on Wednesday). The main concerns are more likely to be lightning and localized flooding through Thursday. As for temperatures, the increased rain chances will temper values, resulting in highs only reaching the lower to mid 80s by Thursday. Lows will generally remain in the 60s, due to elevated moisture. && .LONG TERM... (Friday through Monday) Issued at 1010 PM CDT Mon May 18 2026 A more summerlike pattern will persist through the Day 4-7 period as 5h ridging builds farther into the southeast U.S. and eastern Gulf of America. Southwesterly flow will persist northwest of the ridge, maintaining a moist flow of air into the Gulf States, particularly in the lower MS Valley where 2.0+ inch PWs will reside. Although, there is a corridor of slightly lower values in the 1.5-1.8 inch range over AL into eastern and middle TN, with higher values farther east across the FL peninsula through GA and the Carolinas. Multiple weak impulses will lift northeast through this period, with medium to high chances of showers and thunderstorms each day (diurnally inflated due to heating). High temperatures will be in the lower to middle 80s, with lows in the 60s. Dew points will be in the 60s to around 70 degrees. && .AVIATION... (00Z TAFS) Issued at 443 PM CDT Mon May 18 2026 VFR flight weather conditions are forecast. After 15Z Tuesday, southerly flow will increase to ~10kt with gusts of 15-20kt. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...26 SHORT TERM....26 LONG TERM....17 AVIATION...17