Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
567 FXUS61 KBUF 300533 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 133 AM EDT Sun Aug 30 2026 .WHAT HAS CHANGED... Added some fog to the forecast for overnight through early Monday morning. && .KEY MESSAGES... 1) The chance of rain will gradually increase today from northwest to southeast, with showers continuing tonight across Western NY. 2) Unsettled weather will continue through much of the week with occasional rounds of showers and thunderstorms. && .DISCUSSION... KEY MESSAGE 1...The chance of rain will gradually increase today from northwest to southeast, with showers continuing tonight across Western NY. A sharpening mid level trough will continue to dig southeast across Quebec today, while a strong ridge builds over much of the central US. The interaction between these two large scale features will continue to result in thermal packing and frontogenesis across the Great Lakes today, with a northwest to southeast oriented frontal zone strengthening across the Great Lakes. Frontogenesis and moisture pooling will increase from northwest to southeast today, while passing mid level shortwaves in the northwest flow aloft bring periods of enhanced ascent. The net influence of these features will result in a northwest to southeast increase in rain chances today, with the first of the showers arriving near the Canadian border by late morning or midday. Extensive cloud cover will hold down instability, with only a slight chance of a few isolated weak thunderstorms this afternoon and evening. The strong mid level trough will continue to dig southeast across northern New England and the Canadian Maritimes tonight, with associated flow adjustments in its wake forcing the frontal zone to move south and west. This will focus additional showers across Western NY overnight, while areas from Rochester and the Finger Lakes eastward become mainly dry with a temporary influx of drier mid level air moving south out of Canada. Forecast soundings suggest plenty of low level moisture pooling overnight beneath a shallow frontal inversion, supporting areas of fog after midnight. KEY MESSAGE 2...Unsettled weather will continue through much of the week with occasional rounds of showers and thunderstorms. The northwest to southeast oriented frontal zone will remain draped across the Great Lakes much of the upcoming week, keeping the pattern unsettled. The frontal zone will oscillate back and forth across the area several times over the course of the week, with the frontal position modulated by passing mid level shortwaves and also the influence of composite outflow and cold pools from rounds of showers and thunderstorms. Monday through Monday night, the frontal zone will gradually move back northeast across the area, with a commensurate southwest to northeast increase in rain chances. Instability remains quite limited during this period, with just a slight chance of a few isolated weak thunderstorms. Thunderstorm chances will increase by midweek as an EML plume advects ENE through the Ohio Valley and southern Great Lakes, supporting a reservoir of strong instability just upstream. The most active weather will be along the northern edge of the EML where capping is weaker, and it appears this corridor may setup from Michigan into NY/PA around midweek. Forecast instability and shear profiles suggest severe weather may be a concern midweek, with the risk peaking on Wednesday. It will be several more days before the mesoscale details of the evolution start to become more apparent, which will drive the details of the severe weather risk. Model guidance suggests the frontal zone will move back south and west by Thursday and Friday, with rain chances gradually diminishing across the eastern Great Lakes. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... A northwest to southeast oriented frontal zone will continue to strengthen across the Great Lakes today. The increase in forcing and moisture pooling along the boundary will bring thickening and lowering clouds today, with CIGS remaining in the VFR range until this evening. The first chances of light showers will arrive by late morning or midday along the Canadian border, with rain chances gradually increasing from northwest to southeast through the afternoon. Most of the rain will be light today, with VSBY remaining VFR in most locations. Thunder chances will remain on the low side given the lack of instability, with just a slight chance of a few isolated thunderstorms this afternoon. Tonight, the frontal zone will gradually push southwest with time, focusing most of the additional rain across Western NY while areas east of the Genesee Valley dry out overnight. Low level moisture will pool beneath the shallow frontal inversion, with model guidance suggesting expanding areas of low stratus and fog overnight through early Monday morning. Expect areas of MVFR/IFR CIGS and VSBY to become widespread overnight. Outlook... Monday...Widespread MVFR/IFR in the morning in low stratus and patchy fog, improving to VFR/MVFR in the afternoon. Showers likely at times with a chance of a few thunderstorms in the afternoon. Tuesday through Thursday...VFR/MVFR with occasional rounds of showers and thunderstorms. Storms and heavier showers will produce brief/local IFR. && .MARINE... Southwesterly winds in the 8-12 knot range on both lakes will produce a light chop today, but winds and waves will remain well below Small Craft Advisory criteria. A northwest to southeast oriented frontal zone will remain draped across the Great Lakes through much of the week, with the frontal zone meandering north and south across the lower Great Lakes at times with passing clusters of showers and thunderstorms. Winds and waves are expected to remain below Small Craft Advisory criteria through the period, with occasional periods of light to moderate chop. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Hitchcock AVIATION...Hitchcock MARINE...Hitchcock