Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
189 FXUS61 KBUF 181733 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 133 PM EDT Fri Sep 18 2026 .WHAT HAS CHANGED... Minor changes to the forecast with this update. && .KEY MESSAGES... 1) Dry and cool tonight with rain showers and isolated thunderstorms arriving Saturday night and Sunday. && .DISCUSSION... KEY MESSAGE 1...Dry and cool tonight with rain showers and isolated thunderstorms arriving Saturday night and Sunday. High pressure continues to slide across southern Canada promoting dry weather across western and north-central NY today and most of Saturday. Portions of north-central NY near the Tug Hill and the Black River Valley may see temperatures fall into the upper 30s by Saturday morning as we are only ~2 weeks away from the average first fall freeze for those locations. The next round of precipitation across western NY will arrive Saturday night continuing into Sunday as a frontal boundary settles across the midwest extending eastward towards PA. Isentropic lift along with southerly moisture advection into the frontal boundary will support rain shower development Saturday night. Additionally, multiple shortwave troughs look to pass over the frontal boundary continuing through Sunday before the large scale trough axis in eastern Canada passes through and broad high pressure builds in once again across southern Canada early next week. With the frontal boundary primarily remaining south of the CWA, instability will be limited for the development of deeper convective cores. However, periods of heavy rainfall cannot be ruled out as PWAT values around 1.5 inches sits above the climatological 90th percentile for mid- September and the presence of warm cloud layer depth around 10-12 kft. The latest NBM shows probabilities of exceeding 1 inch of rainfall around 60%, mainly across the Southern Tier, for Saturday night through Sunday. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... Surface high pressure will build across the region through tonight, before moving into New England Saturday. A light northerly wind 5-10 knots will continue across the region this afternoon. A FEW-SCT cumulus deck will erode with the setting sun. Mid-high level clouds are expected to expand across the region tonight through Saturday morning. Widespread VFR conditions will continue through Saturday. Outlook... Saturday...VFR. Saturday night through Sunday...MVFR/IFR with rain across the Southern Tier and Finger Lakes. VFR/MVFR farther north near the Canadian border with a chance of showers. Monday...Mainly VFR with an isolated shower. Monday night through Tuesday...becoming MVFR/IFR with showers likely, especially towards the south. Wednesday...MVFR/IFR with showers across western NY. VFR/MVFR with drier weather further east-northeast. && .MARINE... Elevated northerly winds (10-15 kt) continue across the lakes today as surface high pressure slides from western Ontario into Quebec tonight turning winds to out of the northeast. This will continue to produce light chop on the waters, but remaining below small craft advisory thresholds. Flow will slightly increase and become more easterly on Saturday afternoon leading to light chop for most, but wave heights approaching 3 feet west of Hamlin Beach. Rain showers will return Saturday night into Sunday with another round of elevated flow developing Sunday night into Monday as wave heights approach small craft advisory conditions. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Brothers AVIATION...HSK MARINE...Brothers