052 FXUS61 KBUF 020748 AFDBUF Area Forecast Discussion National Weather Service Buffalo NY 348 AM EDT Mon Jun 2 2025 .SYNOPSIS... High pressure will slowly drift from the Ohio Valley to off the Carolina coast during the first half of the week...while providing us with fair dry weather. After an unseasonably chilly start to this morning...the high will also usher in a significant day to day warming trend that will culminate in mid-summerlike heat on Wednesday. A slow moving frontal system will then bring renewed chances of showers and thunderstorms later on in the week...along with temperatures merely falling back to typical early June levels. && .NEAR TERM /THROUGH TONIGHT/... Regional radar imagery currently shows the last of the nuisance light rain showers associated with the departing upper level trough making their way across central New York...with these expected to finally exit entirely to our south and east over the next couple hours. At the same time lingering lower clouds from the Genesee Valley eastward will also continue to slide southeastward...with the vast majority of these exiting our region by sunrise. This will set the stage for an unseasonably chilly start to the day...with temps even reaching the mid 30s and allowing for some patchy frost within the valleys of the interior Southern Tier before sunrise...for which a Frost Advisory remains in effect. As we push through the day...broad high pressure over the Ohio Valley will drift eastward across the Mid Atlantic States. Plentiful dry air and subsidence attendant to the high will allow for copious amounts of sunshine...with this and warm air advection allowing temperatures to finally rebound back to much more seasonable levels (upper 60s to lower 70s). Tonight the center of the large surface high will make its way to the Virginia-North Carolina border...while a weak warm frontal boundary pushes eastward across Southern Ontario. While isentropic ascent and moisture along this feature may be just enough to touch off a few spotty showers north of Lake Ontario...the airmass across our area looks to be too dry to support pcpn...with just a modest increase in mid and high cloud cover therefore expected in association with this boundary. Otherwise continued warm advection will allow for a considerably milder night...with lows ranging from the lower-mid 40s across interior portions of the Southern Tier/ North Country to the lower to mid 50s across the lake plains of far Western New York. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Strong ridging aloft with surface high pressure settling off the Mid Atlantic coast will help to build heat into the region through mid week. A healthy push of warm air advection will favor the onset of a notable warm up this period, with temperatures peaking Wednesday in the mid 80s to around 90F. The warmest readings will be in the valleys and inland from any immediate influence from the lakes. Dewpoints remaining under 65F, so although the warmth will be noticeable from what we have experienced of late, significant heat related issues are not expected. Profiles are dry underneath the ridge, so no precipitation is expected through Wednesday, before a flattening of the ridge begins with the approach of a shortwave trough and cold front Wednesday night, which may force some scattered showers and thunderstorms. Northwest flow will advect an abundance of elevated Canadian wildfire smoke into the region during the period. This area of incoming smoke will likely obscure the sun at times, similar to the way a cirrus level shield might with a hazy or milky appearance. && .LONG TERM /THURSDAY THROUGH SUNDAY/... A much more unsettled pattern this period as a broad positively tilted trough and stalled elongated frontal boundary to our northwest across the Great Lakes and Quebec very slowly crosses the region. Deep southwest flow extending back to the southern Plains will open the door to a stream of Gulf-based moisture, with several waves of sfc low pressure riding along the boundary as it moves through bringing several rounds of showers through at least Friday. Timing of these rounds remains somewhat uncertain in addition to thunderstorm chances, though peak potential looks to be inland from the lakes Thursday and Friday afternoons. The front will finally manage to cross the region sometime Friday evening/night, with decreasing chances for showers Saturday and Sunday. Lower-end chances linger through Sunday as with uncertainty in regards to how quickly the main trough axis moves through behind this front. Regardless, the frontal passage will allow temperatures to return to more seasonable levels. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... Through sunrise any leftover light rain showers will continue to push southeastward and exit the North Country altogether by 07- 08z...with lingering VFR cloud cover from the Genesee Valley eastward also giving way to clearing skies from west to east. As we push through today...widespread VFR conditions are expected courtesy of high pressure drifting from the Ohio Valley to the Mid Atlantic States. The high will then drift to the Virginia/North Carolina border tonight while maintaining VFR conditions across our area...with just a modest increase in mid and high cloud cover expected in association with a weak warm front pushing eastward across Southern Ontario. Outlook... Tuesday through Wednesday...Mainly VFR. Wednesday night through Friday...VFR/MVFR with showers and thunderstorms likely at times with brief/localized restrictions. && .MARINE... High pressure will over the Ohio Valley will gradually drift to a position off the Carolina coast during the first half of the week. This will result in fair weather prevailing across the Lower Great Lakes through midweek...with a general southwesterly to southerly flow running in the 10 to 15 knot range much of the time. While this may induce a light chop at times...conditions are expected to remain below Small Craft Advisory criteria. Looking further out into the latter portions of the week...a slow- moving frontal system will then bring the risk for some showers and thunderstorms Wednesday night through Friday. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...Frost Advisory until 7 AM EDT this morning for NYZ020-021. MARINE...None. && $$ SYNOPSIS...JJR NEAR TERM...JJR SHORT TERM...TMA LONG TERM...PP AVIATION...JJR MARINE...JJR