Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
463 FXUS61 KBUF 312352 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 752 PM EDT Mon Aug 31 2026 .WHAT HAS CHANGED... Minimal changes this evening. && .KEY MESSAGES... 1) Active weather pattern through midweek with multiple rounds of showers and thunderstorms, including severe thunderstorm potential Tuesday and Wednesday. 2) Warm and humid through midweek with "feels-like" temperatures approaching the low-90s on Wednesday. && .DISCUSSION... KEY MESSAGE 1...Active weather pattern through midweek with multiple rounds of showers and thunderstorms, including severe thunderstorm potential Tuesday and Wednesday. Widespread showers continue across western and north-central NY Monday afternoon and evening as a frontal boundary associated with a low over western Ontario continues to slowly progress northeastward across the area. Showers will become more scattered for areas closer to Lake Erie Monday afternoon, before another round approaches from the west this evening. This boundary will generally remain over the region through midweek with multiple rounds of showers and storms passing overtop of the upper level ridge centered over the southern Ohio River Valley. Solutions from hi-res guidance remains very mixed on the progression of storms from eastern MI across southwest ON into western NY late tonight into early Tuesday morning. However, enhanced flow from a weak shortwave passing over the ridge may provide enough shear for organized storms with gusty winds across the Niagara Peninsula eastward. These storms will continue to move southeast toward the NY/PA border through mid-morning. Behind this subtle feature, little forcing will be present with a low-level cap present, but diurnal circulations may support isolated thunderstorm development along the lake breeze boundaries in the afternoon. If any storms can develop, they would occur with ~1500 J/kg of MLCAPE and up to 35 kt of effective shear and fairly straight hodographs that will support splitting storms. Additionally, steering flow will be aligned with lake breeze boundaries across the Niagara Frontier which is a consideration for excessive rainfall. Storm coverage will increase Tuesday night with better forcing with upstream convection in eastern MI and southwest ON. The strongest shortwave passing through the area and with the best potential for severe thunderstorms looks to be Wednesday as a belt of ~50 kt flow at 500mb passes over the ridge. This will provide ample shear across the lower Great Lakes into portions of the Mid- Atlantic for organized thunderstorms capable of producing strong winds and hail. Any lingering morning convection will once again likely impact timing of CI, but favorable upper level support across a well of 2000+ J/kg CAPE could result in multiple rounds of strong storms in the afternoon as well as overnight into early Thursday morning. KEY MESSAGE 2...Warm and humid through midweek with "feels-like" temperatures approaching the low-90s on Wednesday. As the upper level ridge from the central CONUS shifts over the southeast and Mid-Atlantic by midweek, temperatures aloft will begin to climb, with 850mb temps around 18-20 degC Wednesday. This would be above the climatological 95th percentile for early September with afternoon highs 5-8 degF above normal. Additionally, upper 60s to low 70s dew points will keep western NY fairly uncomfortable humidity wise Tuesday and Wednesday. Overnight lows near 10 degF above normal will also provide little overnight relief. Typical warmer spots across western NY in the Genesee Valley and northern Finger Lakes region may tough Heat Advisory criteria Wednesday afternoon, however duration and coverage is not enough at this time to consider any headlines. Additionally, cloud cover from lingering morning storms or developing afternoon storms may provide relief. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... Rain has become widely scattered this evening allowing for many locations to rebound to VFR conditions. This looks to be short lived however, as rain showers and embedded thunderstorms will return to the area overnight, leading to ceilings dropping to 1000-2000 ft, and visibilities falling to 3-5 miles with patchy fog in between the rain. Some locations could see some brief IFR conditions develop early tomorrow morning, but this will mostly be dependent on where thunderstorms track and how heavy the downpours are. Low end MVFR conditions will hold on through the morning hours as the low levels remain nearly saturated despite rain tapering off. Improvements to VFR are possible tomorrow afternoon as low clouds finally scour out. Outlook... Tuesday Night through Thursday...VFR/MVFR with occasional rounds of showers and thunderstorms. Storms and heavier showers will produce brief/local IFR. Friday and Saturday...Mainly VFR with a slight chance of a shower. && .MARINE... Winds and waves are generally expected to remain below Small Craft Advisory criteria this week. The main exception will be in the vicinity of thunderstorms developing, mainly late Tuesday through Wednesday night. Overall, weak surface mslp gradients are expected, but a frontal boundary will remain over the Great Lakes region bringing chances for showers and storms. Lake Erie looks to remain primarily to the south of this boundary and should expect mainly south to southwest flow. Numerous wind shifts across Lake Ontario are likely this week closer to the oscillating boundary. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ DISCUSSION...Brothers AVIATION...Brothers/SGK MARINE...Brothers