193
FXUS61 KBUF 021121
AFDBUF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
721 AM EDT FRI MAY 2 2025
SYNOPSIS
LOW PRESSURE WILL MOVE NORTHEAST ACROSS SOUTHERN QUEBEC TODAY, WHILE
AN ATTENDANT TRAILING COLD FRONT SAGS SOUTHEAST INTO WESTERN AND
NORTH-CENTRAL NY BRINGING RENEWED CHANCES FOR SHOWERS AND A FEW
THUNDERSTORMS THIS AFTERNOON. A LARGE AREA OF LOW PRESSURE WILL THEN
DEVELOP AND STALL OVER THE OHIO VALLEY THIS WEEKEND, RESULTING IN
CHILLY AND WET WEATHER MUCH OF THE TIME. UNSETTLED WEATHER WILL LAST
THROUGH THE FIRST HALF OF NEXT WEEK AS SLOW MOVING LOW PRESSURE
MEANDERS FROM THE OHIO VALLEY TOWARDS THE EAST COAST.
NEAR TERM /THROUGH TONIGHT/
A COLD FRONT ATTENDANT TO LOW PRESSURE CROSSING SOUTHERN QUEBEC WILL
SLOWLY SAG ACROSS WESTERN AND NORTH-CENTRAL NY TODAY. EXPECT A GOOD
AMOUNT DRY TIME WITH JUST SOME WIDELY SCATTERED LIGHT SHOWERS
THROUGH MIDDAY. AS THE BOUNDARY CONTINUES TO DRIFT SLOWLY
SOUTHEASTWARD AND INSTABILITY INCREASES THIS AFTERNOON, SHOWERS AND
A FEW THUNDERSTORMS WILL INCREASE IN COVERAGE ALONG AND SOUTH OF THE
COLD FRONT, MAINLY FROM THE SOUTHERN TIER INTO THE FINGER LAKES TO
THE SOUTHERN TUG HILL REGION. THERE IS A LOW CHANCE THAT AN ISOLATED
STRONGER STORM OR TWO COULD DEVELOP ACROSS THESE AFOREMENTIONED
AREAS, WITH THE POTENTIAL TO PRODUCE LOCALIZED STRONG WIND GUSTS AND
PERHAPS SOME HAIL. FARTHER NORTH, RAIN CHANCES WILL BE MUCH LOWER
NEAR THE CANADIAN BORDER, ALTHOUGH A FEW SPOTTY SHOWERS CANNOT BE
RULED OUT.
COLD FRONT STALLS OUT OVER OR JUST SOUTHEAST OF THE AREA TONIGHT.
WITH THE LOSS OF DAYTIME HEATING, JUST SOME SCATTERED LIGHT RAIN
SHOWERS AND MAYBE A RUMBLE OF THUNDER WILL LINGER THROUGH THE
EVENING HOURS INTO THE EARLY OVERNIGHT. A WAVE OF LOW PRESSURE WILL
THEN MOVE NORTHEAST ALONG THE BOUNDARY, BRINGING THE LIKELIHOOD FOR
RAIN SHOWERS BACK INTO WESTERN NY LATE TONIGHT.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/
A CLOSED CUTOFF LOW WILL SLOWLY SPIRAL ACROSS THE CORN BELT STATES
THIS PERIOD, WITH WEAK SURFACE LOW REFLECTED AT THE SURFACE OVER THE
OHIO VALLEY. DEEP MOISTURE ALONG A STALLED BAROCLINIC BOUNDARY THAT
IS DRAPED ACROSS NEW ENGLAND TO THE OHIO VALLEY WILL MAINTAIN
SCATTERED TO NUMEROUS RAIN SHOWERS THROUGHOUT THE PERIOD.
RAINFALL THROUGH THE WEEKEND WILL TOTAL A HALF TO ONE INCH...THOUGH
LOWER AMOUNTS ARE POSSIBLE FOR THE SLV WHICH WILL LIE ON THE
NORTHERN GRADIENT OF THE STALLED FRONTAL BOUNDARY/PRECIPITATION
AXIS.
COOLEST DAYTIME HIGHS FOR THIS WEEKEND WILL BE SOUTH OF LAKE ONTARIO
WHERE A NORTHEAST FLOW OVER THE COLD LAKE WATERS WILL SLOW THE
DAYTIME WARMING ALONG THE SHORELINE AND INLAND, ESPECIALLY ON SUNDAY
WHEN THE FLOW WILL BE A LITTLE STRONGER.
LONG TERM /MONDAY THROUGH THURSDAY/
AS THE CLOSED LOW SPIRALS EASTWARD OUR LOW LEVEL FLOW WILL VEER FROM
THE NORTHEAST TO MORE SOUTHEASTERLY FOR MONDAY. THIS WILL PROMOTE A
MILDER PATTERN. WITH THIS MILDER PATTERN WILL COME INCREASING
INSTABILITY, THAT COUPLED WITH INCREASING LAPSE RATES UNDER THE POOL
OF COLD AIR ALOFT (UPPER LEVEL LOW) DEEPER CONVECTION WILL BE
ENCOURAGED, WITH THUNDERSTORM CHANCES INCREASING THROUGH THE
AFTERNOON AND EVENING HOURS.
SHOWERS, AND PERHAPS A FEW THUNDERSTORMS LINGER TUESDAY AND
WEDNESDAY WITH THE PASSAGE OF THE CLOSED LOW ALOFT, WITH DRIER AIR
THURSDAY ALLOWING FOR A LIKELY DRY DAY...THOUGH PLENTY OF CUMULUS
CLOUDS FORMING WITHIN THE NORTHWEST CYCLONIC FLOW ALOFT.
AVIATION /12Z FRIDAY THROUGH TUESDAY/
INCREASE IN LOW LEVEL MOISTURE ACROSS WESTERN NY AHEAD A WEAK COLD
FRONT NEARING THE AREA FROM THE WEST HAS BROUGHT MVFR CONDITIONS TO
THE NIAGARA FRONTIER (KBUF/KIAG) AND WESTERN SOUTHERN TIER
(KJHW) THIS MORNING AS EXPECTED. MVFR CONDITIONS WILL SPREAD
EAST ACROSS THE GENESEE VALLEY AND EASTERN LAKE ONTARIO REGION
AS WELL, AND WILL PERSIST THROUGH EARLY/MID AFTERNOON ACROSS
MUCH OF THE REGION. OTHERWISE, JUST EXPECTING CHANCES FOR SOME
SCATTERED LIGHT SHOWERS THROUGH MIDDAY OR SO.
MOST AREAS WILL RETURN TO VFR AT SOME POINT THIS AFTERNOON
(EXCEPTION MAY BE HIGHER TERRAIN), HOWEVER THE SLOW MOVING COLD
FRONT WILL BE SLOWLY SAGGING SOUTHEAST THROUGH WESTERN AND NORTH-
CENTRAL NY BY THIS TIME. AS INSTABILITY INCREASES WITH DAYTIME
HEATING, DO EXPECT SHOWERS TO INCREASE IN COVERAGE AHEAD OF THE
FRONT ALONG WITH A FEW STORMS, MAINLY FROM THE WESTERN SOUTHERN TIER
TO THE FINGER LAKES INTO THE SOUTHERN TUG HILL REGION. ANY FLIGHT
RESTRICTIONS WITH THIS ACTIVITY WILL BE INTERMITTENT AND LOCALIZED
WITHIN ANY HEAVIER SHOWERS OR STORMS THAT DEVELOP.
COLD FRONT CONTINUES TO ONLY VERY SLOWLY PRESS SOUTHEAST TONIGHT.
FURTHER INHIBITING FRONTAL PROGRESSION WILL BE A WAVE OF LOW
PRESSURE RIDING NORTHEAST ALONG THE BOUNDARY THAT WILL BRING MORE
WIDESPREAD SHOWERS BACK IN ACROSS WESTERN NY BY LATE TONIGHT.
INCREASING MOISTURE AHEAD OF THE THIS NEXT ROUND OF RAIN WILL BRING
DETERIORATING FLIGHT CONDITIONS WITH MVFR/IFR DEVELOPING ACROSS THE
WESTERN SOUTHERN TIER THIS EVENING, AND MVFR ACROSS MUCH OF THE
REMAINDER OF THE AREA. EXCEPTION MAY BE TOWARD FAR NORTHWESTERN
AREAS (KIAG/KART) FARTHER REMOVED FROM THE FRONT WHERE CONDITIONS
MAY NOT FALL BELOW (LOW) VFR. SOLID IFR CONDITIONS WILL EXPAND FROM
THE SOUTHERN TIER TO THE FINGER LAKES SECOND HALF OF TONIGHT, WITH
MVFR LIKELY FOR ALL REMAINING AREAS BY EARLY SATURDAY MORNING.
OUTLOOK...
SATURDAY THROUGH TUESDAY...OCCASIONAL SHOWERS WITH AREAS OF
MVFR/IFR.
MARINE
LOW PRESSURE WILL MOVE THROUGH SOUTHERN QUEBEC BY TODAY. SSW WINDS
WILL CONTINUE TO PRODUCE SMALL CRAFT ADVISORY CONDITIONS AT THE
NORTHEAST END OF LAKE ONTARIO THROUGH THIS MORNING. OTHERWISE, FOR
THE REST OF LAKE ONTARIO AND LAKE ERIE, EXPECT CHOPPY CONDITIONS
THROUGH TONIGHT AS A COLD FRONT SLOWLY MOVES SOUTHEAST ACROSS THE
AREA. MAINLY LIGHT NORTHEASTERLIES CAN THEN BE EXPECTED LATE TONIGHT
THROUGH SATURDAY NIGHT WITH NO MORE THAN SOME LIGHT CHOP ON THE
LAKES.
BUF WATCHES/WARNINGS/ADVISORIES
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LOZ045.
SYNOPSIS...HITCHCOCK/JM
NEAR TERM...JM
SHORT TERM...THOMAS
LONG TERM...THOMAS
AVIATION...JM
MARINE...JM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page