


Area Forecast Discussion
Issued by NWS Buffalo, NY
Issued by NWS Buffalo, NY
998 FXUS61 KBUF 180643 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 243 AM EDT Mon Aug 18 2025 .SYNOPSIS... A large area of high pressure will track across eastern Canada through Tuesday afternoon, providing cooler and drier weather into Tuesday morning. The potential for at least some showers and thunderstorms will increase the the middle of the week as a weak sfc low tracks near the region. High pressure late in the week will return drier weather to western and north central NY. && .NEAR TERM /THROUGH TONIGHT/... The region will be under the influence of a large area of high pressure over eastern Canada during the period, resulting in fair dry weather through tonight. Mostly clear skies are expected this morning, except for some stratus at times early this morning. High clouds during the day today should increase off of upstream convection over the northern plains/upper midwest. There is still some uncertainty with the high clouds moving in, but if higher clouds dont fill in, and the sky remains mostly clear, then some afternoon diurnal cumulus clouds will be possible mainly south of Lake Ontario. Northeast winds this morning in the 5 to 10 mph range will gust some through the morning, and weaken from the late morning through the afternoon. Temperatures today will be in the upper 60s to upper 70s from the higher terrain to the lower elevations. Tonight, dry weather will continue through the night with some of the high clouds increasing as well, with some mid level clouds increasing across the Southern Tier from the south. Winds will veer from the northeast to the the southeast through the night, and also become light. With light winds in place, temperatures will cool to the mid 40s over the higher terrain east of Lake Ontario, to the mid 50s for the lower elevations of WNY. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Mid-level troughing will build across the Northeast with multiple shortwave troughs moving through the region mid-week. An expansive surface high over Eastern Canada will maintain mostly dry weather across the forecast area Tuesday. A few showers may move into the Niagara Frontier by late Tuesday, as a shortwave trough and deeper moisture approach the forecast area from the west. A broad area of low pressure will move from the Upper Great Lakes region to the Ohio Valley Tuesday through Wednesday. Warm air advection will spread from west to east across the region while an inverted surface trough sets up across the Lower Great Lakes Tuesday night. Showers will move from west to east across the forecast area Tuesday night through Wednesday. Uncertainty is high in regards to the coverage of showers, as deterministic models have backed off on precip across the forecast area. For now, went with low to medium chances of showers across the forecast area Tuesday night. Shower chances diminish across western zones then move to interior portions of the forecast area Wednesday. Average rainfall amounts will be light through Wednesday morning. Instability increases Wednesday afternoon and a few thunderstorms are possible which could produce localized higher rainfall. A trough axis near the region will maintain low chances of showers Wednesday night. Temperatures will rebound Tuesday with highs in the upper 70s to low 80s, mid 80s in the Genesee Valley. Temperatures will likely be a few degrees lower Wednesday with clouds and showers around the area. Low temperatures will reach the upper 50s to low 60s Tuesday night and Wednesday night. && .LONG TERM /THURSDAY THROUGH SUNDAY/... An upper level ridge will build across the eastern Great Lakes region Thursday through Friday night. Dry weather will return to the region during this time. The pattern takes a big turn as a deep upper level trough moves into the Great Lakes region this weekend. Warm weather will persist through Saturday. As the first of a few cold fronts approach the region, showers and a few thunderstorms are possible Saturday, however confidence is low. A cold front is forecast to move through the region sometime late in the weekend. Multiple rounds of showers and storms are possible across the region Sunday into Monday. By Monday, mean 850mb temperatures are forecast to fall to near 8C. Lake effect rain showers will be possible into early next week. A notable cooldown is expected Sunday into next week. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... Mainly VFR this morning with a few brief periods of lower VSBY to IFR a times for areas east of Lake Ontario, including KART when winds briefly lower, but then clear out as winds increase some. VFR expected for today with northeast winds of up to around 10 mph weakening late in the morning and through the afternoon. Some increase in high clouds will be possible from upstream convection. Tonight, mainly VFR with winds veering from the northeast to the southeast through the night. High clouds are expected to continue to increase, and some mid-level clouds are possible for the Southern Tier late tonight. Outlook... Tuesday and Tuesday night...Mainly VFR. Isolated to scattered showers. Wednesday...Localized cig/vsby restrictions possible especially early in the day, otherwise mainly VFR with decreasing chances for showers and thunderstorms. Thursday and Friday...VFR. && .MARINE... SCA`s are in place for both lakes with northeast winds today, for Lake Erie through most of the morning and through most of the afternoon on Lake Ontario. Winds will weaken on Lake Erie and then Lake Ontario through the morning and into the afternoon. Winds will veer from the northeast to the southeast from this evening through tonight as high pressure builds across Quebec. Winds the next few days are expected to stay below SCA levels from this evening onward. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...Beach Hazards Statement through this afternoon for NYZ001>006. MARINE...Small Craft Advisory until 11 AM EDT this morning for LEZ040- 041. Small Craft Advisory until 4 PM EDT this afternoon for LOZ042>045. && $$ SYNOPSIS...SW NEAR TERM...SW SHORT TERM...HSK LONG TERM...HSK AVIATION...SW MARINE...SW