654 
FXUS61 KBUF 232319
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
719 PM EDT THU MAY 23 2013

.SYNOPSIS...
A COLD FRONT WILL TRACK ACROSS THE REGION TONIGHT WITH PERIODS OF 
SHOWERS AS MUCH COOLER AIR ENTERS THE REGION. THE RAIN WILL SLOWLY 
END FROM WEST TO EAST ON FRIDAY AND SET THE STAGE FOR A DRY BUT COOL 
HOLIDAY WEEKEND AS HIGH PRESSURE BUILDS OVER THE GREAT LAKES REGION. 
TEMPERATURES WILL REBOUND BACK TO ABOVE AVERAGE NEXT WEEK.

&&

.NEAR TERM /THROUGH FRIDAY/...
RADAR IMAGERY THIS EVENING SHOWING RAIN SHOWERS BECOMING MORE 
WIDESPREAD ACROSS WESTERN NY WITH THE APPROACH OF AN UPSTREAM MID 
LEVEL TROUGH EVIDENT ON WATER VAPOR IMAGERY OVER THE CENTRAL LAKES. 
SURFACE OBS SHOWING THE SURFACE COLD FRONT HAS CLEARED MOST OF THE 
CWA AT 23Z...AND WILL MOVE INTO THE SOUTHERN TIER AND FINGER LAKES 
SHORTLY. TEMPERATURES ARE TAKING A NOSE DIVE AS STRONG CAA TAKES 
HOLD BEHIND THE FRONT. 

MOST OF THE THUNDERSTORMS HAVE PUSHED SOUTH AND EAST OF THE AREA 
EARLY THIS EVENING...FOLLOWING THE GREATER INSTABILITY. A SCATTERED 
STORM OR TWO IS STILL POSSIBLE THROUGH MID EVENING ACROSS THE 
INTERIOR SOUTHERN TIER AND LEWIS COUNTY...BUT AFTER THAT ANY THUNDER 
RISK WILL BE OVER AS A MUCH COOLER AND MORE STABLE AIRMASS SWEEPS 
INTO THE REGION.

MOISTURE WILL REMAIN PLENTIFUL BEHIND THE COLD FRONT AND WITH THE 
UPPER LEVEL COLD TROUGH STILL TO OUR WEST...LIFT AHEAD OF THIS 
FEATURE WILL CONTINUE THE LIGHT RAIN SHOWERS OVER OUR REGION THROUGH 
TONIGHT AND INTO FRIDAY MORNING. FOG WILL BE POSSIBLE ACROSS THE 
HIGHER ELEVATIONS OF THE SOUTHERN TIER LATER TONIGHT WHERE LOWERING 
CLOUDS CIGS MAY ALSO BRING REDUCED VISIBILITIES. FOR NOW IN THE 
GRIDS WILL JUST INCLUDE PATCHY FOG ACROSS THE HIGHER ELEVATIONS OF 
THE SOUTHERN TIER WHERE CONFIDENCE FOR FORMATION IS GREATER DUE TO 
THE RECENT SHOWERS THIS AFTERNOON OVER THIS AREA.         

WITH THE COLD AIR ADVECTION BEHIND THIS COLD FRONT TEMPERATURES 
TONIGHT WILL DROP BELOW NORMAL...INTO THE LOW TO MID 40S.

THE AXIS OF THE UPPER LEVEL TROUGH WILL REACH TOWARDS WESTERN NEW 
YORK TOMORROW MORNING. EXPECT SHOWERS TO MAINLY BE ALONG AND AHEAD 
OF THIS AXIS WHERE THE BEST SYNOPTIC LIFT WILL BE FOUND. THIS TROUGH 
WILL CONTINUE TO DIG...EVENTUALLY CLOSING OFF FROM THE MAIN FLOW 
NEAR THE MASON DIXON LINE TOMORROW NIGHT. EXPECT SHOWERS TO SLOWLY 
END FROM WEST TO EAST AS THE LIFT AND MOISTURE ADVANCES 
SOUTHEASTWARD...AND DRIER AND MUCH COOLER AIR PULLS IN FROM THE 
NORTHWEST. CLOUDY SKIES THROUGH THE MORNING WILL DIMINISH WITH SOME 
SUNSHINE RETURNING THROUGH THE AFTERNOON. WITH THE LINGERING CLOUDS 
AND COLD POOL ALOFT (NEAR 0C AT 850 HPA) HIGHS TOMORROW WILL BE 
CHILLY. AN EARLY APRIL FEEL TO THE AIR WITH MOST AREAS IN THE LOW TO 
MID 50S.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
THE WEATHER PATTERN LOOKS RELATIVELY QUIET DURING THE PERIOD AS A 
COOL DOME OF HIGH PRESSURE BUILDS DOWN FROM CANADA. HEIGHTS WILL 
GRADUALLY BUILD AS THE CUT OFF LOW PROGRESSES INTO NEW ENGLAND. MAIN 
CONCERN THIS PERIOD WILL BE OVERNIGHT TEMPERATURES BOTH FRIDAY NIGHT 
AND SATURDAY NIGHT AS THE UNSEASONABLY COLD AIRMASS SETTLES INTO THE 
REGION. THERE LOOKS TO BE ENOUGH OF A PRESSURE GRADIENT IN BETWEEN 
DEPARTING LOW AND APPROACHING SURFACE RIDGE TO PREVENT A WIDESPREAD 
FROST. FREEZING TEMPERATURES...ALTHOUGH NOT TOTALLY OUT OF THE 
QUESTION FOR PORTIONS OF THE SOUTHERN TIER MAY BE TOUGH TO GET WITH 
THE TIGHTER GRADIENT IN PLACE...WOULD FEEL MORE CONFIDENT IN A 
FREEZE IF WINDS COULD COMPLETELY DROP OFF. FOR NOW WILL LEAVE 
FROST/FREEZE HEADLINE OUT OF FORECAST...BUT CONTINUE TO MENTION IN 
HWO PRODUCT.

AREA WILL REMAIN ON THE WESTERN PERIPHERY OF THE UPPER CIRCULATION 
MOVING UP INTO NEW ENGLAND SUNDAY. THERE MAY BE A BIT MORE CLOUD 
COVER ACROSS THE EASTERN PORTION OF THE AREA...BUT CONFIDENCE 
REMAINS HIGH THAT MAINLY SUNNY CONDITIONS WILL BE MAINTAINED OVER 
THE WEST.  

BOTH WEEKEND DAYS LOOK TO BE ON THE COOL SIDE...WITH SATURDAY THE 
COOLEST OF THE TWO DAYS WITH HIGHS MAINLY IN THE UPPER 50S TO LOWER 
60S...WITH LOWER TO MID 60S ON SUNDAY...BUT EVEN COOLER BOTH DAYS 
ALONG THE IMMEDIATE LAKESHORE AREAS.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
LATEST MEDIUM RANGE GUIDANCE OR AT LEAST THE BULK OF IT CONTINUES TO 
SUGGEST A HIGH AMOUNT OF CONFIDENCE IN DRY WEATHER HOLDING THROUGH 
THE PERIOD...ALONG WITH A GRADUAL WARMING TREND...AS THE UPPER LOW 
OVER NORTHERN NEW ENGLAND/CANADIAN MARITIMES SLOWLY LIFTS AWAY FROM 
THE AREA. MOST OF THIS PERIOD WILL FEATURE AN UPPER LEVEL RIDGE OVER 
THE MISSISSIPPI VALLEY BUILDING EASTWARD. SURFACE HIGH WILL SET UP 
ALONG THE EAST COAST...RESULTING IN THE DEVELOPMENT A WARMER 
SOUTHERLY FLOW OF AIR. RETURN FLOW WILL BRING SOME MINIMAL RISK OF 
ISOLATED AFTERNOON CONVECTION LATER IN THE PERIOD...BUT CONFIDENCE 
IN PLACEMENT OF CONVECTION TOO LOW TO MENTION AT THIS POINT.

&&

.AVIATION /23Z THURSDAY THROUGH TUESDAY/...
THE SURFACE COLD FRONT HAS PUSHED SOUTH OF THE REGION THIS EVENING. 
AN UPPER LEVEL TROUGH WILL SLOWLY CROSS THE REGION AND KEEP 
OCCASIONAL SHOWERS GOING OVERNIGHT EVEN BEHIND THE SURFACE COLD 
FRONT. THE COMBINATION OF ONGOING RAIN AND A STEEPENING LOW LEVEL 
FRONTAL INVERSION WILL CONTINUE TO PROMOTE THE DEVELOPMENT OF MVFR 
CIGS THIS EVENING...WHICH SHOULD LOWER TO FAIRLY WIDESPREAD IFR 
OVERNIGHT AS THE LOW LEVELS SATURATE. VSBY MAY ALSO BE REDUCED TO AT 
LEAST MVFR AT TIMES...ALTHOUGH MODERATE NORTH TO NORTHWEST WINDS 
SHOULD PREVENT ANY BONIFIDE FOG. THE ONE EXCEPTION MAY BE ON THE 
HIGHEST HILLS OF THE SOUTHERN TIER AND FINGER LAKES WHERE THE LOWER 
CLOUD DECK MAY INTERSECT THE HILLTOPS. 

ON FRIDAY THE SHOWERS WILL SLOWLY END FROM WEST TO EAST DURING THE 
DAY AS THE UPPER LEVEL TROUGH MOVES SLOWLY EAST. IFR CIGS WILL 
IMPROVE TO MVFR WITH THE END OF RAIN...THEN SHOULD SCATTER OUT TO 
VFR DURING THE AFTERNOON ACROSS MUCH OF WESTERN NY AS A DRIER 
AIRMASS BUILDS IN FROM THE NORTHWEST.


OUTLOOK...  
FRIDAY AFTERNOON...MVFR IMPROVING TO VFR AS SHOWERS DIMINISH. 
SATURDAY THROUGH TUESDAY...VFR.

&&

.MARINE...
A COLD FRONT WILL CROSS THE EASTERN GREAT LAKES THIS EVENING AND 
WITH MODEST COLD AIR ADVECTION OF THE LAKES OVERNIGHT AND TOMORROW 
WAVES WILL INCREASE TO 4 TO 6 FEET ON BOTH LAKES. WAVES WILL
BEGIN TO DIMINISH LATER FRIDAY AFTERNOON. WINDS WILL INCREASE
SOME AGAIN ON SATURDAY AND POSSIBLY BRING SOME SMALL CRAFT
CONDITIONS TO THE EASTERN END OF LAKE ONTARIO EARLY SATURDAY
MORNING.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT FRIDAY 
         FOR LEZ040-041.
         SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 2 PM 
         EDT FRIDAY FOR LOZ043-044.
         SMALL CRAFT ADVISORY UNTIL NOON EDT FRIDAY FOR LOZ042.
         SMALL CRAFT ADVISORY FROM 2 AM TO NOON EDT FRIDAY FOR 
         LOZ045.

&&

$$

SYNOPSIS...HITCHCOCK/THOMAS
NEAR TERM...HITCHCOCK/THOMAS
SHORT TERM...TMA
LONG TERM...TMA
AVIATION...HITCHCOCK
MARINE...THOMAS