Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
817 FXUS61 KBUF 182315 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 715 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 /00Z SATURDAY THROUGH WEDNESDAY/... Aloft W`erly to WNW`erly flow and embedded disturbances affect Western and Central NY through 00Z/Sun. At the surface, a ridge continues to affect our area as the embedded high pressure center wobbles SE`ward from near James Bay toward the Canadian Maritimes. Our regional surface winds are expected to trend light and variable before 12Z/Sat. From 12Z through 00Z/Sun, our regional surface winds should trend NE`erly to SE`erly around 5 to 10 knots. Dry weather and mainly VFR are expected through the TAF period. Scattered to widespread mid-level and especially upper-level cloudiness will accompany the disturbances aloft and stream generally E`ward to ESE`ward over Western and Central NY. In North-Central NY, steam mist/fog resulting in MVFR to LIFR is possible along and near the Black River between ~07Z/Sat and ~13Z/Sat, including at/near KART. Outlook... Saturday night through Sunday night...Periodic showers with MVFR or worse expected. Isolated thunderstorms possible in/near the Western Southern Tier Saturday night into Sunday morning. Monday...Dry weather and VFR likely. Monday night through Wednesday...Periodic showers with MVFR or worse possible. Isolated thunderstorms possible Tuesday night and Wednesday. && .MARINE... Northeasterly flow will veer more east-northeasterly tonight while slightly increasing, with a moderate chop developing from Sodus Bay west to the Niagara River with wave heights approaching 3 feet. Winds become more easterly on Saturday while also slowly weakening with wave heights of 2-3 feet generally confined to areas from Hamlin Beach westward, with mainly light chop on the remainder of the lakes. Winds mainly 10 knots or less Saturday night through at least a portion of Sunday morning with generally light chop. Otherwise, rain showers will return Saturday night into Sunday with freshening northeasterlies developing Sunday night into Monday, likely leading to an extended period of small craft conditions that may persist through midweek on portions of the lower lakes. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Brothers AVIATION...Jaszka MARINE...JM