Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
224 FXUS61 KBUF 071721 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 121 PM EDT Mon Sep 7 2026 .WHAT HAS CHANGED... Minor changes to the forecast with this update. && .KEY MESSAGES... 1) Dry weather will prevail through Tuesday night. 2) A cold front will cross the eastern Great Lakes Wednesday through Wednesday night, producing showers and thunderstorms. && .DISCUSSION... KEY MESSAGE 1...Dry weather will prevail through Tuesday night. High pressure will settle south into the Mid Atlantic states tonight before drifting off the east coast by Tuesday night. A surface ridge extending back into PA and Western NY will maintain dry weather for most of the area through Tuesday night. A sharpening mid level trough crossing the Canadian Maritimes will push a backdoor cold front south across northern NY and New England, but any showers associated with this front should remain north and east of Jefferson and Lewis counties late tonight through Tuesday morning. River valley fog will develop once again across the Southern Tier and Finger Lakes late tonight and persist through mid morning Tuesday. KEY MESSAGE 2...A cold front will cross the eastern Great Lakes Wednesday through Wednesday night, producing showers and thunderstorms. A mid level trough will move from far northwest Ontario Wednesday to northern Quebec by Thursday, with the southern extent of height falls and a belt of enhanced low/mid level flow spreading east across the Great Lakes. Large scale forcing for ascent will arrive later Wednesday and Wednesday evening ahead of the trough, with low level convergence becoming enhanced along a pre-frontal trough and lake breeze boundaries Wednesday afternoon and evening. A narrow plume of rich moisture will be captured and advected northeast into our region just ahead of the system, with surface dewpoints rising into the 65-70F range and PWATs briefly exceeding 2 inches. The quality of moisture and adequate dynamics will support an area of showers and scattered thunderstorms crossing the region from northwest to southeast, peaking in coverage late Wednesday afternoon and evening. The high PWAT environment will support torrential downpours in any storms, although the progressive nature of the system should keep the flood risk relatively low. Moderate deep layer shear will overspread the area Wednesday, but instability is forecast to remain weak with very warm mid levels and poor low/mid level lapse rates. The lack of stronger instability will likely hold down the severe weather risk. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... Diurnal cumulus will continue inland from the lakes through late afternoon with VFR bases. Tonight, mainly clear to partly cloudy skies will continue. River valley fog will develop overnight and last through mid morning Tuesday across the Southern Tier and Finger Lakes with local IFR/LIFR. VFR will prevail for the rest of Tuesday once the fog burns off across the Southern Tier. Outlook... Wednesday...VFR/MVFR. Showers and a few thunderstorms, mainly later in the afternoon through Wednesday evening. Local/brief IFR in thunderstorms. Thursday...MVFR CIGS early, improving to VFR. A small chance of a few showers across the Southern Tier. Friday through Saturday...Mainly VFR. && .MARINE... High pressure will provide light winds and minimal wave action through Tuesday. Southerly winds will increase late Tuesday night as the pressure gradient tightens between high pressure drifting off the east coast and low pressure moving into northwest Ontario. Winds will become southwest and increase further Wednesday as a cold front approaches, with winds and waves increasing to Small Craft Advisory criteria later Wednesday through Wednesday night on both lakes as the cold front crosses the region. Elevated winds and waves will persist through Thursday behind the departing cold front before winds diminish Friday. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Hitchcock AVIATION...Hitchcock MARINE...Hitchcock