104
FXUS61 KBUF 040651
AFDBUF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
251 AM EDT MON MAY 4 2026
WHAT HAS CHANGED
INCREASED WINDS AND GUSTS A BIT FURTHER FOR TODAY, PARTICULARLY
ACROSS AREAS NORTHEAST OF LAKE ERIE.
NO SIGNIFICANT CHANGES HAVE BEEN MADE WITH THIS UPDATE.
KEY MESSAGES
1) WARMER AND BREEZY/WINDY CONDITIONS INTO TUESDAY, WITH MUCH COOLER
TEMPERATURES RETURNING BY MIDWEEK.
2) INCREASINGLY ACTIVE WEATHER RETURNS TONIGHT AND TUESDAY, WITH
ANOTHER SOAKING RAINFALL EXPECTED LATER TUESDAY INTO WEDNESDAY.
DISCUSSION
KEY MESSAGE 1...WARMER AND BREEZY/WINDY CONDITIONS INTO TUESDAY,
WITH MUCH COOLER TEMPERATURES RETURNING BY MIDWEEK.
THROUGH TUESDAY...RELOADING LONGWAVE TROUGHING OVER CENTRAL CANADA
WILL GRADUALLY DIG SOUTHEASTWARD ACROSS THE UPPER GREAT LAKES...WITH
AN ASSOCIATED SURFACE LOW MAKING ITS WAY FROM WESTERN ONTARIO
PROVINCE TO NORTHERN QUEBEC...AND ITS TRAILING COLD FRONT SLOWLY
EASING ITS WAY SOUTHEASTWARD ACROSS OUR REGION TUESDAY AFTERNOON AND
EVENING. PRIOR TO THE PASSAGE OF THIS BOUNDARY...OUR REGION WILL
REMAIN EMBEDDED WITHIN THE DEEP SOUTHWESTERLY FLOW FOUND BETWEEN THE
SURFACE LOW/COLD FRONT AND HIGH PRESSURE OVER THE WESTERN
ATLANTIC...WHICH WILL ACT TO PUMP PROGRESSIVELY WARMER AIR ACROSS
OUR REGION THROUGH TONIGHT/EARLY TUESDAY.
WITH 850 MB TEMPS CLIMBING TO BETWEEN +7C AND +10C BY LATER TODAY
AND THEN PEAKING AROUND +10C LATER TONIGHT AND EARLY TUESDAY...IT
SHOULD CERTAINLY FEEL A LOT MORE LIKE MAY BETWEEN NOW AND TUESDAY
MORNING. GIVEN GOOD MIXING ALONG WITH INCREASING AMOUNTS OF SUNSHINE
TODAY...THE ABOVE TEMPS ALOFT SHOULD SUPPORT HIGHS MOSTLY IN THE
UPPER 60S TO MID 70S...WITH DOWNSLOPING LEADING TO THE WARMEST
READINGS ACROSS THE GENESEE VALLEY AND FINGER LAKES. LOWS TONIGHT
WILL THEN RANGE THROUGH LOWER 50S ACROSS THE NORTH COUNTRY TO THE
MID-UPPER 50S ELSEWHERE. GIVEN SOME CONTINUED UNCERTAINTY IN THE
EXACT TIMING OF THE COLD FRONT AND ITS ASSOCIATED PCPN...THERE IS
SOME CORRESPONDING UNCERTAINTY AND RESULTANT FORECAST BUST POTENTIAL
WITH RESPECT TO BOTH THE MAGNITUDE AND TIMING OF OUR HIGH TEMPS ON
TUESDAY...WITH AN EARLIER FROPA/PCPN ONSET FAVORING COOLER TEMPS AND
A LATER TIMING FAVORING WARMER READINGS.
WITH A RELATIVELY TIGHT PRESSURE GRADIENT IN PLACE BETWEEN THE
SURFACE LOW/COLD FRONT TO OUR NORTHWEST AND RIDGING OVER THE WESTERN
ATLANTIC...WE CAN ALSO EXPECT FAIRLY BREEZY TO WINDY CONDITIONS TO
PERSIST UP UNTIL THE TIME OF THE COLD FRONTAL PASSAGE ON TUESDAY.
PRIOR TO THAT TIME A FEW LOW LEVEL JET SEGMENTS WILL ALSO BRUSH/
SLIDE ACROSS OUR NORTHWESTERN PERIPHERY...THEREBY LEADING TO SOME
PERIODS OF WINDIER CONDITIONS NORTHEAST OF THE LAKES. THE STRONGEST
OVERALL WINDS MAY ACTUALLY COME DURING TODAY NE OF LAKE ERIE...WHEN
GOOD DIURNAL HEATING SHOULD HELP TO MORE EFFECTIVELY MIX HIGHER
MOMENTUM AIR ALOFT ASSOCIATED WITH A PASSING 30-40 KNOT LLJ SEGMENT
DOWN TO THE SURFACE. GIVEN THIS...EXPECT SURFACE WINDS TO GUST TO AS
HIGH AS 40 MPH OR SO ACROSS THE NIAGARA FRONTIER...WITH SOME 30-35
MPH GUSTS EXTENDING AS FAR EAST AS ROCHESTER/THE LOWER GENESEE
VALLEY. AS WE MOVE INTO TONIGHT...THE LOSS OF HEATING AND CONTINUED
WARM ADVECTION SHOULD HELP TO BETTER INHIBIT MIXING OF WINDS FROM
ANOTHER...STRONGER PASSING LLJ SEGMENT DOWN TO THE SURFACE...THOUGH
BREEZY CONDITIONS WILL STILL PERSIST. RENEWED DIURNAL WARMING MAY
THEN ALLOW FOR ANOTHER PERIOD OF WINDIER CONDITIONS TO DEVELOP
DOWNWIND OF THE LAKES ON TUESDAY...THOUGH THE EXACT MAGNITUDE AND
TIMING OF THIS REMAINS IN QUESTION GIVEN THE UNCERTAINTIES IN THE
TIMING OF THE COLD FRONT MENTIONED ABOVE. FOR NOW...HAVE CAPPED
GUSTS ON TUESDAY TO THE 30-35 MPH RANGE GIVEN THIS UNCERTAINTY.
FOLLOWING THE PASSAGE OF THE COLD FRONT...UPPER-LEVEL TROUGHING AND
MUCH COOLER AIR WILL OVERSPREAD OUR REGION AGAIN TUESDAY NIGHT
THROUGH FRIDAY...THEN WILL REMAIN IN PLACE THROUGH AT LEAST THE
UPCOMING WEEKEND. THIS WILL RESULT IN ANOTHER ROUND OF BELOW NORMAL
TEMPERATURES THROUGHOUT THIS TIME FRAME...THOUGH THESE MAY NOT BE
QUITE AS COOL AS WHAT WE JUST EXPERIENCED LAST WEEK.
KEY MESSAGE 2...INCREASINGLY ACTIVE WEATHER RETURNS TONIGHT AND
TUESDAY, WITH ANOTHER SOAKING RAINFALL EXPECTED LATER TUESDAY INTO
WEDNESDAY.
WHILE THE PASSAGE OF AN INITIAL WARM FRONTAL SEGMENT AND TRAILING
WEAK SHORTWAVE TROUGH MAY PRODUCE A FEW MORE SPRINKLES AND SCATTERED
SHOWERS INTO EARLY THIS MORNING...CONDITIONS SHOULD MOSTLY BE DRY
THROUGH TODAY. THIS WILL START TO CHANGE TONIGHT INTO TUESDAY
MORNING THOUGH...WHEN THE PASSAGE OF ANOTHER WARM FRONTAL SEGMENT
WILL BRING THE POTENTIAL FOR SOME ADDITIONAL SCATTERED TO NUMEROUS
SHOWERS...WITH AN ISOLATED WEAK THUNDERSTORM OR TWO ALSO POSSIBLE
GIVEN THE PRESENCE OF SOME WEAK TO VERY MODEST INSTABILITY. THINGS
WILL THEN TREND MORE MARKEDLY DOWNHILL TUESDAY AFTERNOON INTO
WEDNESDAY AS THE COLD FRONT SLOWS DOWN AND BECOMES INCREASINGLY WAVY
AS IT PASSES THROUGH/JUST TO THE EAST OF OUR AREA. INCREASING DEEP-
LAYER ASCENT ATTENDANT TO THESE FEATURES AND PWATS CLIMBING TO
AROUND/A LITTLE OVER 1 INCH WILL SUPPORT THE DEVELOPMENT OF
WIDESPREAD SHOWERS TUESDAY AFTERNOON INTO TUESDAY EVENING...WHEN
SOME WEAK TO MODEST INSTABILITY MAY ALSO SUPPORT THE POTENTIAL FOR
SOME ISOLATED SCATTERED THUNDERSTORMS...PARTICULARLY FROM THE
SOUTHERN TIER NORTHEASTWARD ACROSS THE FINGER LAKES AND INTO THE
NORTH COUNTRY. AS WE GET INTO THE COOLER AIR ON THE BACKSIDE OF THE
FRONT...THE SHOWERS WILL THEN TEND TO EVOLVE INTO MORE OF A
STRATIFORM RAIN LATER TUESDAY NIGHT INTO WEDNESDAY MORNING AS A
SURFACE WAVE RIPPLES BY JUST TO OUR SOUTHEAST...WITH THE RAIN THEN
TAPERING OFF WEDNESDAY AFTERNOON/EVENING FOLLOWING THE PASSAGE OF
THIS WAVE.
ALL OF THE ABOVE WILL ADD UP TO ANOTHER WIDESPREAD SOAKING RAINFALL
FROM TUESDAY THROUGH WEDNESDAY...WITH 36-HOUR BASIN-AVERAGE RAINFALL
AMOUNTS STILL LOOKING TO RANGE ON THE ORDER OF 0.75"-1.25" PER THE
LATEST SUITE OF GUIDANCE...WITH SOME POTENTIAL FOR LOCALLY HIGHER
AMOUNTS IF ANY LOCALIZED CONVECTIVE ENHANCEMENT CAN DEVELOP. ALL
THIS SAID...GIVEN THAT THIS WOULD BE COMING SOME 5-7 DAYS AFTER OUR
LAST SOAKING RAINFALL...SUCH BASIN-AVERAGE AMOUNTS WOULD BE UNLIKELY
TO CAUSE ANY HYDROLOGIC ISSUES.
THE ABOVE SAID...GIVEN THE RELATIVELY FAST LOW-MID LEVEL FLOW THAT
WILL BE IN PLACE OUT AHEAD OF THE COLD FRONT...THERE MAY ACTUALLY BE
A LOWER-END RISK FOR A FEW STRONG TO MARGINALLY SEVERE STORMS
TUESDAY AFTERNOON/EVENING PROVIDED ENOUGH INSTABILITY CAN DEVELOP.
THIS WILL PARTICULARLY BE THE CASE FROM PORTIONS OF THE FINGER LAKES
NORTHEASTWARD ACROSS THE NORTH COUNTRY...WHERE INSTABILITY SHOULD BE
THE GREATEST, AND WHERE SPC HAS INTRODUCED A MARGINAL RISK AREA IN
THEIR LATEST DAY 2 CONVECTIVE OUTLOOK. SHOULD THIS OCCUR...STRONG
WIND GUSTS WOULD BE THE PRIMARY SEVERE WEATHER THREAT...WITH LARGE
HAIL A SECONDARY RISK GIVEN SUFFICIENTLY COOL TEMPS WELL ALOFT.
AVIATION /06Z MONDAY THROUGH FRIDAY/
VFR FLIGHT CONDITIONS WILL PREVAIL THROUGH TODAY AS A WARM FRONT
BRINGS PERIODS OF MID LEVEL CLOUDS. A FEW SHOWERS ARE POSSIBLE, BUT
VSBY RESTRICTIONS ARE EXPECTED TO REMAIN AOA 6SM. A PERSISTENT LOW
LEVEL JET WILL MAINTAIN SOUTHWEST WIND GUSTS OF 15-25 KNOTS THROUGH
TODAY. THESE GUSTS WILL INCREASE TO NEAR 35 KNOTS AT KBUF AND KIAG
AFTER 16Z.
OUTLOOK...
TONIGHT...VFR/MVFR. INCREASING CHANCES FOR SHOWERS.
TUESDAY...MVFR. COVERAGE OF SHOWERS INCREASES, WITH A FEW
THUNDERSTORMS POSSIBLE IN THE AFTERNOON
TUESDAY NIGHT...MAINLY IFR WITH WIDESPREAD RAIN.
WEDNESDAY...IMPROVEMENT TO MVFR/VFR POSSIBLE WITH STEADY RAIN
TAPERING OFF. LOW-END CHANCE FOR SHOWERS LINGERS.
THURSDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
FRIDAY...RESTRICTIONS POSSIBLE WITH INCREASING CHANCES FOR SHOWERS
IN THE AFTERNOON.
MARINE
THROUGH TUESDAY HIGH PRESSURE WILL SLIDE ACROSS WESTERN ATLANTIC
WHILE LOW PRESSURE TRACKS ACROSS NORTHERN ONTARIO AND QUEBEC...WITH
A SLOW-MOVING COLD FRONT CROSSING OUR REGION TUESDAY AFTERNOON AND
EVENING. PERIODS OF MODERATELY BRISK SOUTHWESTERLY FLOW ARE EXPECTED
AT TIMES OUT AHEAD OF THIS FRONT...BRINGING THE LIKELIHOOD FOR
ROUNDS OF NEAR-SCA TO SCA CONDITIONS. THESE ARE MOST LIKELY ACROSS
LAKE ERIE, THE UPPER NIAGARA RIVER, AND THE EASTERN END OF LAKE
ONTARIO GIVEN THE ONSHORE WIND COMPONENT.
A FEW THUNDERSTORMS AND LOCALLY HIGHER WINDS/WAVES WILL ALSO BE
POSSIBLE ON TUESDAY WITH THE APPROACH AND PASSAGE OF THE COLD FRONT.
BUF WATCHES/WARNINGS/ADVISORIES
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LEZ040-
041.
DISCUSSION...JJR
AVIATION...TMA
MARINE...JJR/PP
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