FXUS61 KBUF 151821 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 221 PM EDT Thu Oct 15 2026 .WHAT HAS CHANGED... Minor changes to the forecast with this update. && .KEY MESSAGES... 1) Periods of rain tonight through Friday, along with gusty winds. 2) Much colder Friday night through Saturday night with a few wet snowflakes possible early Saturday morning. && .DISCUSSION... KEY MESSAGE 1...Periods of rain tonight through Friday, along with gusty winds. Sharp mid level trough will advance into the Great Lakes tonight through Friday. Surface low pressure will strengthen across the Great lakes tonight and move into southern Ontario by Friday morning, reaching the Saint Lawrence Valley by Friday afternoon. The expected track of the surface low will allow the warm sector to build into the lower Great Lakes. A period of strong warm advection and moisture transport, enhanced by a 50+ knot low level jet, will arrive tonight and support an initial wave of rainfall. This rain will arrive in western New York by around midnight, then spread quickly northeast overnight. Additional periods of rain will continue Friday through Friday evening as the trailing cold front moves southeast across the region, supported by mid level height falls and right entrance region jet dynamics. Marginal instability in the warm sector may support a few embedded thunderstorms as well late tonight through Friday. Rainfall amounts will vary widely across the area, generally ranging from 0.25" to 1.0". Terrain will play an important role given the strong boundary layer flow, with downslope areas of the Lake Erie shore and Genesee Valley likely on the low end of the range, while higher terrain is more likely to be on the higher end of the range from upslope enhancement. There may be a few small areas that exceed 1.0" if embedded convection develops. It will become quite windy late tonight through Friday. A 50+ knot low level jet will propagate across the eastern Great Lakes late tonight through Friday morning. Gusts will increase into the 25-35 mph range areawide, with gusts possibly reaching or exceeding 40 mph in downslope areas along the Lake Erie shore and north of the Tug Hill Plateau briefly. Boundary layer flow will quickly swing around to the southwest Friday morning through mid afternoon, with gusts still in the 25-35 mph range in most areas, and up to 45 mph northeast of Lake Erie across the Niagara Frontier. KEY MESSAGE 2...Much colder Friday night through Saturday night with a few wet snowflakes possible early Saturday morning. Strong cold advection will develop Friday night in the wake of the departing low, with 850 mb temperatures dropping into the -5C to -8C range by Saturday morning. The cold air aloft will support increasing lake induced instability overnight with a brief lake response, but short NNW fetch and a rapidly drying synoptic scale airmass will keep lake effect muted and brief. Lake effect and upslope rain showers will develop southeast of the lakes Friday night, with a few wet snowflakes possibly mixing in very late Friday night through early Saturday morning before the lake effect showers quickly end by late morning. The best chance of a few snowflakes will be across higher terrain, but no accumulation is expected. The coldest airmass of the fall season so far will arrive for Saturday, with highs only in the 40s areawide, and even upper 30s across the highest terrain despite some afternoon sunshine. Temperatures will drop back into the low to mid 30s Saturday night on the lake plains, with some 20s likely across the Southern Tier valleys and North Country. The cold air will quickly depart, with temperatures back above average by early next week. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... Most of our forecast area has improved to VFR, however the last of the MVFR CIGS is hanging on early this afternoon across the Niagara Frontier (KBUF/KIAG), with this area forecast to scatter out by mid afternoon or so per latest visible satellite imagery showing low level cloud footprint continuing to "shrink" in size as drier air off the deck mixes down to the surface. VFR flight conditions are then expected to continue areawide for the remainder of the afternoon, with thickening/lowering mid and upper level decks across western NY late today into the early evening. Flight conditions will deteriorate fairly rapidly from southwest to northeast through the first half of tonight with a few showers possible. Increasing moisture/forcing along the leading edge of a strong 50-60 knot LLJ within a strong WAA regime will bring a period of steadier rain/isolated thunder across the area from southwest to northeast through the second half of tonight, with CIGS deteriorating to MVFR/IFR areawide. Our area will briefly become entrenched in the warm sector Friday morning as an area of low pressure passes by just to our north. This will allow steadier rain to taper off to more in the way of showery precipitation with MVFR/IFR CIGS hanging on through the end of the 18Z TAF period. Cold front will press east across the area later Friday morning through the afternoon bringing the next period of steadier showers along and ahead of the boundary, with mainly MVFR CIGS persisting through Friday afternoon. Potential for a brief period of LLWS still looks possible late tonight into early Friday as the strong 50-60 knot LLJ moves overhead. However, stronger winds off the deck are expected to start mixing down to the surface fairly soon after arrival, thus window for any LLWS will likely be rather short-lived to nil. Expect increasing surface wind gusts late tonight through Friday, with gusts of 20-30 knots areawide, and up to 35 knots northeast of the lakes later Friday morning through the afternoon. A few gusts to near 40 knots cannot be ruled out across the Niagara Frontier (KBUF/KIAG) from late morning through mid afternoon. Outlook... Friday night...Mainly MVFR CIGS with scattered showers, mixing with a few wet flakes late. Saturday...Areas of MVFR CIGS with scattered rain/wet snow showers early, improving to VFR. Sunday through Tuesday...VFR. && .MARINE... Northeast winds around 15 knots will continue to produce choppy conditions on both lakes this afternoon, but winds and waves will remain just below Small Craft Advisory criteria. Low pressure will track across the southern Great Lakes tonight, reaching southern Ontario Friday morning. This low will continue to deepen as it moves northeast across the Saint Lawrence Valley Friday, reaching the Canadian Maritimes by Saturday. Southerly winds will increase overnight tonight ahead of the system, then quickly veer to the southwest and west Friday as the low passes by just north of the lower Great Lakes, followed by gusty north-northwest winds Friday night through Saturday morning. Sustained winds during this timeframe will average 20-30 knots, producing high end Small Craft Advisory conditions on both lakes. Some periodic gusts to near gale force are possible. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...Small Craft Advisory from 2 AM Friday to 11 AM EDT Saturday for LEZ040-041. Small Craft Advisory from 8 AM Friday to 11 AM EDT Saturday for LOZ042. Small Craft Advisory from 8 AM Friday to 2 PM EDT Saturday for LOZ043-044. Small Craft Advisory from 2 AM Friday to 2 PM EDT Saturday for LOZ045. && $$ DISCUSSION...TMA AVIATION...JM MARINE...TMA