771 FXUS61 KBUF 022207 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 607 PM EDT Mon Jun 2 2025 .SYNOPSIS... High pressure over the Ohio Valley today will gradually drift off the east coast through midweek, providing a stretch of dry weather along with a significant warming trend. Midsummer heat will peak on Wednesday. A cold front will then cross the area Thursday with a few showers and thunderstorms. The front will stall just south of the area Thursday night, then a wave of low pressure will move along the front and bring more rain and scattered thunderstorms to the area Friday through Saturday. && .NEAR TERM /THROUGH TUESDAY NIGHT/... Surface high pressure over the Ohio Valley this evening will gradually build to the Mid Atlantic coast Tuesday, then just off the east coast Tuesday night. Strong subsidence and dry air beneath a building mid/upper level ridge will continue to support dry weather and mainly clear skies tonight through Tuesday night. The one minor exception, a warm frontal segment will move from west to east across southern Ontario later tonight through Tuesday morning. Warm advection and isentropic ascent associated with this feature will bring a modest increase in cloud cover for a few hours, especially near and east of Lake Ontario overnight through Tuesday morning. A few sprinkles cannot be ruled out, but most of these should stay in southern Canada if they materialize. A layer of smoke aloft from Canadian wildfires will remain over the area through midweek, but so far HRRR model guidance suggests most of this will remain elevated well off the surface. The main story will continue to be the dramatic warm-up following the chilly weekend. Ongoing warm advection will keep lows tonight much milder than last night. Highs Tuesday will soar into the low 80s for lower elevations, with a few mid 80s readings possible in the typical warm spots of the Genesee Valley. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Wednesday will be the warmest day of the week as the mid level ridge axis drifts to the east coast. Surface high pressure will remain parked off the east coast, allowing for a continuation of southwesterly flow and warm advection. Highs will reach well into the 80s in most areas, with some low 90s possible in the typical warm spots of the Genesee Valley and Central NY. The southwest flow will keep areas northeast of Lake Erie and Lake Ontario a little cooler. Dewpoints will start to creep up into the lower 60s, but not high enough to result in any appreciable heat index above and beyond the air temperature. A cold front over the central Great Lakes Wednesday night will begin to spread increasing clouds into our region overnight. The cold front will cross the eastern Great Lakes Thursday, bringing the likelihood of showers and a few thunderstorms. The latest guidance continues to suggest a morning frontal passage, with unfavorable diurnal timing for stronger convection. The cold front is forecast to settle south into northern Pennsylvania late Thursday and Thursday night. Weak high pressure will build into southern Ontario and Quebec, with associated drier air and subsidence allowing most of the rain to end, with the possible exception of the Southern Tier in closer proximity to the stalling frontal zone. && .LONG TERM /FRIDAY THROUGH MONDAY/... Friday through Saturday, a southern stream shortwave is forecast to move from the Ohio Valley into NY/PA. The shortwave moving atop the WSW-ENE oriented frontal zone just to our south will result in one or several baroclinic waves developing on the front, with the resulting waves of low pressure moving over or just south of the eastern Great Lakes. Strong low level frontogenesis and moisture convergence will be topped by strong upper level divergence in the right entrance region of a strengthening upper level jet streak over southern Quebec. The quality and layout of forcing and moisture suggest the potential for a corridor of heavy rainfall along the stalled frontal zone, so this will need to be monitored through the week. The system will exit east into New England later Saturday or Saturday night. High pressure will then build into the Great Lakes Sunday through early Monday with a return to dry weather. Another cold front will move through the Great Lakes later Monday, and may bring a few showers to the eastern Great Lakes later in the day. It will be a little cooler and less humid behind the front, but highs will likely still be in the 70s, near average for this time of year. && .AVIATION /22Z MONDAY THROUGH SATURDAY/... For the 00Z TAFS VFR flight conditions are found and these conditions shall persist through the forecast period with a light southerly flow. There will be a weak warm front passing through the vicinity of Lake Ontario region tonight with a modest increase in mid level clouds, noted most for the KART airfield. High pressure will bring clear skies tomorrow and into tomorrow night. Light southerly flow at the surface will continue tomorrow night (precluding any fog formation), but aloft our region will be on the fringe of a belt of stronger flow through the Central Great Lakes, with possible LLWS at 2K feet for the western TAF sites late Tuesday night. Outlook... Wednesday...VFR. Thursday...VFR/MVFR with showers likely and a chance of thunderstorms. Friday...VFR/MVFR with showers likely and a chance of thunderstorms. Saturday...MVFR with showers likely. && .MARINE... West to southwest winds in the 10-15 knot range will continue to produce a light chop on Lake Erie and Lake Ontario through this evening. High pressure over the Ohio Valley will gradually drift to the Mid Atlantic coast Tuesday, then just offshore of the east coast by Wednesday. Light winds Tuesday will increase Wednesday as the pressure gradient increases behind the departing high. This will bring moderate southwest winds, strongest on the west end of Lake Ontario. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...None. MARINE...None. && $$ SYNOPSIS...Hitchcock NEAR TERM...Hitchcock SHORT TERM...Hitchcock LONG TERM...Hitchcock AVIATION...Thomas MARINE...Hitchcock