465
FXUS61 KBUF 270733
AFDBUF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
333 AM EDT TUE MAY 27 2025
SYNOPSIS
HIGH PRESSURE OVER NEW ENGLAND WILL MAINTAIN DRY AND WARM WEATHER
TODAY, WITH HIGH CLOUDS THICKENING FROM SOUTHWEST TO NORTHEAST. LOW
PRESSURE WILL THEN MOVE INTO THE GREAT LAKES WEDNESDAY, BRINGING
ANOTHER PERIOD OF RAIN TO THE REGION. UNSETTLED WEATHER WILL
CONTINUE THURSDAY THROUGH NEXT WEEKEND WITH A CHANCE OF A FEW
SHOWERS EACH DAY AS A DEEP TROUGH BECOMES ESTABLISHED ACROSS THE
NORTHEAST.
NEAR TERM /THROUGH TONIGHT/
CLEAR SKIES WILL GRADUALLY GIVE WAY TO INCREASING HIGH CLOUDS FROM
SOUTHWEST TO NORTHEAST EARLY THIS MORNING. SOME PATCHY FOG WILL
CONTINUE TO DEVELOP, MAINLY FROM THE VALLEYS OF THE SOUTHERN TIER
EAST ACROSS THE FINGER LAKES TO CENTRAL NY.
SURFACE HIGH PRESSURE WILL REMAIN IN PLACE TODAY FROM NORTHWEST
ONTARIO PROVINCE TO OFF THE SOUTHERN NEW ENGLAND COAST, MAINTAINING
DRY WEATHER ACROSS OUR REGION. AN EXPANSIVE SHIELD OF DENSE CIRRUS
AHEAD OF THE NEXT SYSTEM WILL CONTINUE TO OVERSPREAD THE AREA FROM
SOUTHWEST TO NORTHEAST, WITH THICKENING CLOUD COVER. THE DAY TO DAY
WARMING TREND WILL CONTINUE, WITH HIGHS TRENDING A LITTLE ABOVE
AVERAGE TODAY. A LIGHT NORTHEAST FLOW WILL KEEP THE SOUTH SHORE OF
LAKE ONTARIO MUCH COOLER.
TONIGHT, A MID LEVEL CLOSED LOW WILL ADVANCE EAST TOWARDS THE UPPER
MISSISSIPPI VALLEY, WHILE WEAK SURFACE LOW PRESSURE MOVES INTO THE
OHIO VALLEY. CLOUDS WILL CONTINUE TO THICKEN AND LOWER OVERNIGHT.
DRY WEATHER WILL PREVAIL MOST OF THE NIGHT, WITH RAIN CHANCES
INCREASING DURING THE PRE-DAWN HOURS ACROSS THE WESTERN SOUTHERN
TIER. MORE ON THIS SYSTEM IN THE SHORT TERM SECTION BELOW.
SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/
DURING THE FIRST HALF OF THIS PERIOD A BROAD...CLOSED UPPER LEVEL
LOW INITIALLY OVER THE UPPER MIDWEST WILL OPEN UP INTO MORE OF A
BROAD...POSITIVELY-TILTED TROUGH ACROSS THE GREAT LAKES/NORTHEAST
AND SOUTHEASTERN CANADA...WITH AN EMBEDDED LEAD SHORTWAVE IMPULSE
EJECTING NORTHEASTWARD ACROSS OUR REGION WEDNESDAY NIGHT AND
THURSDAY. MEANWHILE AT THE SURFACE...DOUBLE-BARRELLED LOW PRESSURE
INITIALLY DRAPED FROM THE OHIO VALLEY TO THE CAROLINAS WILL ALSO
LIFT NORTHEASTWARD ACROSS THE LOWER GREAT LAKES AND NEW ENGLAND LATE
WEDNESDAY THROUGH THURSDAY.
INCREASING MOISTURE AND ISENTROPIC ASCENT/DVCA ASSOCIATED WITH THIS
SYSTEM WILL RESULT IN ANOTHER ROUND OF WIDESPREAD LIGHT TO POSSIBLY
MODERATE RAIN WORKING ACROSS OUR REGION FROM SOUTHWEST TO NORTHEAST
WEDNESDAY THROUGH THE FIRST HALF OF THURSDAY...WITH THE BULK OF THE
RAIN LASTING BETWEEN 12-18 HOURS AT ANY GIVEN LOCATION. THE RAIN
WILL THEN TEND TO TAPER OFF TO SOME LEFTOVER...MORE SCATTERED
SHOWERS FOR MOST FOLLOWING THE PASSAGE OF THE MAIN SURFACE TROUGH
AXIS AND WITH THE ARRIVAL OF SOME DRIER AIR ALOFT LATER WEDNESDAY
NIGHT THROUGH THE FIRST PART OF THURSDAY...THOUGH THE DEVELOPMENT OF
SOME WEAK DIURNALLY-DRIVEN INSTABILITY MAY THEN LEAD TO A SLIGHT
UPTICK IN SHOWER COVERAGE/POTENTIAL THURSDAY AFTERNOON...WITH THE
BULK OF THIS FOCUSED ALONG OUR SOUTHEASTERN PERIPHERY. DURING THIS
LATTER TIME FRAME...JUST ENOUGH INSTABILITY MAY DEVELOP TO ALSO
ALLOW FOR AN ISOLATED WEAK THUNDERSTORM OR TWO ACROSS THE NORTH
COUNTRY.
THURSDAY NIGHT THROUGH FRIDAY NIGHT THE BROAD UPPER LEVEL TROUGH
OVER OUR REGION WILL AMPLIFY OVER TIME AS COPIOUS ADDITIONAL
SHORTWAVE ENERGY DROPS SOUTH-SOUTHEASTWARD FROM HUDSON BAY...
RESULTING IN A FAIRLY DEEP FULL-LATITUDE TROUGH GETTING CARVED OUT
ACROSS THE EASTERN CONUS BY THE END OF THE PERIOD. THIS BEING
SAID...MODEL GUIDANCE STILL EXHIBITS SOME SIGNIFICANT DIFFERENCES
WITH RESPECT TO THE STRENGTH/POSITIONING OF A WAVE ALONG THE
SOUTHERN PERIPHERY OF THE ORIGINAL WEAKER TROUGH AND ITS SUBSEQUENT
INTERACTION WITH ONE OR MORE COLD FRONTS DROPPING SOUTHEASTWARD
ACROSS OUR REGION FRIDAY-FRIDAY NIGHT...WHICH RESULTS IN CONTINUED
UNCERTAINTY IN PCPN POTENTIAL DURING THIS TIME FRAME. WITH THIS IN
MIND...HAVE KEPT A GENERAL CHANCE OF SHOWERS IN THE FORECAST FOR
NOW FOR THE LAST 24 HOURS OF THIS PERIOD.
AS FOR TEMPS...THESE WILL AVERAGE OUT A BIT COOLER THAN NORMAL
DURING THIS PERIOD...THOUGH ALSO NOWHERE NEAR AS COOL AS WHAT WE
EXPERIENCED LAST WEEK...WITH THE WARMEST DAY OF THE PERIOD COMING ON
FRIDAY.
LONG TERM /SATURDAY THROUGH MONDAY/
MEDIUM RANGE GUIDANCE IS IN FAIRLY GOOD AGREEMENT ON DEEP UPPER-
LEVEL TROUGHING REMAINING ACROSS OUR REGION DURING SATURDAY...WITH
THE CORE OF THE TROUGH THEN GRADUALLY LIFTING OUT TO OUR NORTHEAST
SUNDAY AND MONDAY. MULTIPLE PASSING SHORTWAVE IMPULSES AND THE
RESERVOIR OF COOL AIR ALOFT ATTENDANT TO THE TROUGH SHOULD KEEP
BELOW NORMAL TEMPERATURES AND AT LEAST SOME CHANCE OF SHOWERS INTACT
THROUGH THE WEEKEND...WITH THE GREATEST POTENTIAL FOR THESE FOCUSING
ON EACH AFTERNOON WITH DIURNAL DESTABILIZATION. GIVEN MODEL TRENDS
TOWARD AN INITIALLY DEEPER AND COOLER TROUGH...HAVE ELECTED TO KNOCK
TEMPS BACK A BIT FROM BOTH CONTINUITY AND BLENDED GUIDANCE FOR THE
WEEKEND. BY MONDAY THE DEPARTURE OF THE CORE OF THE TROUGH AND THE
INTRODUCTION OF SOME MODEST WARMING ALOFT SHOULD RESULT IN A GENERAL
REDUCTION IN SHOWER CHANCES ALONG WITH TEMPS AT LEAST CLIMBING BACK
CLOSER TO NORMAL.
AVIATION /08Z TUESDAY THROUGH SATURDAY/
HIGH PRESSURE STRETCHING FROM NORTHWEST ONTARIO TO OFF THE SOUTHERN
NEW ENGLAND COAST WILL MAINTAIN DRY WEATHER AND VFR TODAY, WITH A
SHIELD OF DENSE CIRRUS MOVING INTO THE AREA FROM SOUTHWEST TO
NORTHEAST. THE HIGH CLOUDS WILL CONTINUE TO TO THICKEN AND LOWER
TONIGHT. RAIN CHANCES WILL BEGIN TO INCREASE DURING THE PRE-DAWN
HOURS OF WEDNESDAY ACROSS THE WESTERN SOUTHERN TIER. DRY LOW LEVELS
WILL KEEP CIGS/VSBY VFR INITIALLY AS THE FIRST RAIN ARRIVES.
OUTLOOK...
WEDNESDAY...VFR DETERIORATING TO MVFR/IFR FROM SOUTHWEST TO
NORTHEAST. RAIN OVERSPREADING THE AREA.
THURSDAY THROUGH SATURDAY...VFR/MVFR WITH A FEW SHOWERS AT TIMES.
MARINE
HIGH PRESSURE WILL MAINTAIN LIGHT WINDS AND WAVE ACTION TODAY WITH
LIGHT ONSHORE BREEZES DEVELOPING THIS AFTERNOON. RELATIVELY LIGHT
WINDS WILL CONTINUE THROUGH WEDNESDAY.
LOW PRESSURE WILL THEN CROSS THE GREAT LAKES WEDNESDAY NIGHT AND
THURSDAY. WINDS WILL BECOME SOUTHWEST AND INCREASE THURSDAY AS THIS
SYSTEM PASSES BY, BRINGING CHOPPY CONDITIONS ESPECIALLY ON LAKE
ERIE.
BUF WATCHES/WARNINGS/ADVISORIES
NY...NONE.
MARINE...NONE.
SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...HITCHCOCK
MARINE...HITCHCOCK
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