000
FXUS61 KBUF 141727
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
127 PM EDT TUE MAY 14 2013

.SYNOPSIS...
A WARM FRONT WILL MOVE ACROSS WESTERN AND CENTRAL NEW YORK LATE
TONIGHT AND WEDNESDAY...FOLLOWED BY A WEAK COLD FRONT.  SHOWERS AND
POSSIBLY THUNDERSTORMS WILL ACCOMPANY THIS UNSETTLED
PATTERN...MAINLY DURING THE MORNING IN WESTERN NY AND TOWARD NOON OR
THE AFTERNOON TIME-FRAME IN THE CENTRAL PORTION OF THE STATE.  HIGH
PRESSURE WILL THEN SLOWLY MOVE INTO THE REGION FOR A DRY END OF THE
WEEK.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE STRETCHES ALONG THE EASTERN SEABOARD THIS
AFTERNOON.  A WEAK RIDGE ALOFT CAN BE FOUND OVER THE NATIONS MID
SECTION WITH NW FLOW OVERHEAD.  SOME THIN HIGH CLOUDS HAVE MOVED
INTO THE CENTRAL PORTION OF THE STATE...WHILE A MID LEVEL DECK
CONTINUES TO WORK INTO SOUTHERN ONTARIO PROVENCE WITH SOME REPORTS
OF VIRGA OR VERY LIGHT PRECIPITATION.

FOR THE AFTERNOON...EXPECT INCREASING CLOUD COVER OVER WESTERN NY
WITH LESS CLOUD COVER TO THE EAST.  NO PRECIPITATION IS EXPECTED
WITH A DRY AIRMASS IN THE LOW LEVELS PER 12Z REGIONAL SOUNDINGS AND
NEAR-TERM FORECASTS.

TONIGHT A WARM FRONT WILL MOVE INTO THE REGION WITH INCREASING
TEMPERATURE AND MOISTURE ALOFT...CREATING A STRONG INVERSION IN THE
LOW LEVELS.  HIGH RESOLUTION ENSEMBLES THROUGH 12Z /SSEO/ INDICATE A
THREAT FOR SHOWERS OVER FAR WESTERN NY...BUT INDIVIDUAL SIMULATED
REFLECTIVITY OUTPUT DO NOT INDICATE ANY CONVECTION
OVERHEAD...PROBABLY DUE STABLE AIRMASS UNDERNEATH THE STRONG
INVERSION.  WILL DOWNPLAY MODELED PRECIPITATION OUTPUT AND CONTINUE
TO INDICATE SPRINKLES...ONLY IN WESTERN NY.

FOR WEDNESDAY...THE WARM FRONT WILL PUSH ACROSS THE STATE WITH A
WEAK COLD FRONT ON ITS HEELS.  THIS PUTS WESTERN AND CENTRAL NY
BRIEFLY IN THE WARM SECTOR.  THE STRONG INVERSION CONTINUES TO RULE
OUT ANY SURFACE BASED CONVECTION...MEANING THAT STORMS WILL HAVE TO
BE ONGOING AND WELL MAINTAINED UPSTREAM AS THEY CROSS MI AND
SOUTHERN ONTARIO AS THEY WILL BE ELEVATED.  TIMING FOR ANY
CONVECTION...AND RAIN IN GENERAL APPEARS TO BE HIGHEST DURING THE
MORNING OR EARLY AFTERNOON OVER WESTERN NY...AND LATER...MID DAY OR
AFTERNOON FOR CENTRAL NY.  HAVE A HIGH CONFIDENCE IN MEASURABLE
PRECIPITATION...BUT MUCH LOWER CONFIDENCE ON CONVECTIVE THREAT.

THE MAIN SYSTEM THAT WILL BE RESPONSIBLE FOR WEATHER ON WEDNESDAY
CAN BE FOUND MOVING QUICKLY EASTWARD NEAR THE NORTHERN BORDER OF MN.
CURRENTLY PRECIPITATION AND CONVECTION ASSOCIATED WITH THIS FEATURE
ARE QUITE TAME IN THE VICINITY OF THE SURFACE FRONTS WHICH ARE
DISPLACED TO THE SOUTH OVER SOUTHERN MN...ALTHOUGH EXPECT SOME
DEVELOPMENT LATER THIS AFTERNOON OVER SOUTHERN WI WITH FURTHER
DAYTIME HEATING.  WILL HAVE TO WATCH THIS AREA FOR STRONG CONVECTIVE
DEVELOPMENT AS A POTENTIAL INDICATOR FOR WEATHER FOR WEDNESDAY...AS
UPSTREAM DATA IN THIS AREA IS OFTEN A GOOD INDICATION OF WEATHER
24HRS LATER DOWNSTREAM /IE IN UPSTATE NY/.  IF UPSTREAM CONVECTION
IS WEAK...CONFIDENCE FOR A NEGLIGIBLE/NON EVENT IN NY WILL
INCREASE.  CURRENT FORECAST SOUNDINGS SHOW AN IMPRESSIVE AMOUNT OF
SHEAR AND INSTABILITY ALOFT WEDNESDAY...BUT THE LOW LEVEL STABLE
AIRMASS CONTINUES TO BE A MAJOR DETERRENT.  IN ADDITION...THE TIMING
FOR A DECENT CONVECTIVE EVENT CURRENTLY DOES NOT APPEAR TO BE QUITE
RIGHT...WITH A STRONGER INVERSION DURING THE MORNING LOWERING THE
POTENTIAL FOR CONVECTIVE WINDS REACHING THE SURFACE.

IN TERMS OF TEMPERATURES...IN SPITE OF THE WEAK COLD FRONT LATER IN
THE DAY ON WEDNESDAY...TEMPERATURES SHOULD WARM NICELY BY THE END OF THE DAY
AS THE AIRMASS DRIES OUT...WITH 70S IN MOST LOCATIONS AND 60S EAST
OF LAKE ONTARIO...MARKING THE RETURN TO SPRING AFTER OUR RECENT COLD
SPELL.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
ANY CONVECTION THAT DOES OCCUR SHOULD WIND DOWN QUICKLY WEDNESDAY
EVENING AS THE LOW TRACKS EAST INTO QUEBEC AND IT/S ASSOCIATED
COLD FRONT PUSHES SOUTH OF THE GREAT LAKES. THE HEAVILY MODIFIED
PACIFIC AIRMASS WILL NOT RESULT IN A SUBSTANTIAL TEMPERATURE DROP
HOWEVER WITH LOWS ONLY EXPECTED TO COOL INTO THE UPPER 40S
OVERNIGHT. MODELS ARE NOW IN GOOD AGREEMENT ON PUSHING THE
BOUNDARY ALL THE WAY THROUGH THE FORECAST AREA...AND AS SUCH HAVE
GONE WITH A DRIER AND SLIGHTLY COOLER FORECAST FOR THURSDAY. WITH
HIGHS IN THE LOWER 70S AND DEWPOINTS IN THE 40S AND PLENTY OF
SUNSHINE...THURSDAY SHOULD SHAPE UP TO BE A VERY PLEASANT DAY
INDEED. THE DRY CONDITIONS WILL CONTINUE INTO THURSDAY NIGHT AS
HIGH PRESSURE BUILDS OVER THE GREAT LAKES WITH FAIR SKIES AND LOWS
IN THE 40S.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
12Z MEDIUM RANGE MODELS ALL IN PRETTY GOOD AGREEMENT SHOWING A
FRONTAL BOUNDARY BEING FORCED SOUTH TOWARD THE OHIO RIVER FRIDAY IN
RESPONSE TO IMPRESSIVE GREAT LAKES/NORTHEAST CONUS HEIGHT FALLS.
HIGH PRESSURE WILL SETTLE OVER THE LOWER LAKES REGION BRIEFLY...
LEADING TO A DRY FRIDAY OVER WESTERN AND CENTRAL NEW YORK. THE
FORECAST TREND IS THEN TO TURN MORE UNSETTLED AS RETURN MOISTURE AND
APPROACHING WARM FRONT WILL INCREASE THE CHANCES OF CONVECTIVE
ACTIVITY AS WE HEAD INTO THE WEEKEND AND EARLY NEXT WEEK AS LONGWAVE
TROUGH ADVANCES INTO THE CENTRAL CONUS. WARMER TEMPERATURES WILL
CONTINUE WITH DAYTIME HIGHS REACHING INTO THE 70S EACH DAY...AND
NIGHTTIME LOWS GENERALLY RANGING IN THE UPPER 40S TO MID 50S.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A DEPARTING HIGH PRESSURE AREA WILL PROVIDE THE AREA WITH VFR
CONDITIONS THROUGH TONIGHT AS A WARM FRONT APPROACHES FROM THE
WEST.  LOOK FOR LOWERING MID LEVEL CIGS AND INCREASING THREAT FOR
SHOWER ACTIVITY TOWARD 12Z IN WESTERN NY...SEVERAL HOURS LATER IN
CENTRAL NY.  VFR CONDITIONS ARE EXPECTED TO CONTINUE AS THE WARM
FRONT MOVES THROUGH LATE TONIGHT OR WEDNESDAY...WITH CLEARING SKIES
FOLLOWING A COLD FRONT LATER IN THE AFTERNOON/EVENING.

WINDS WILL PICKUP DURING THE AFTERNOON AS A LOW LEVEL JET CROSSES
THE REGION AND EVENTUALLY MIXES DOWN TO THE SURFACE WITH THE COLD
FRONT.  THIS WILL POTENTIALLY BRING WIND SHEAR CONDITIONS TO THE
REGION AS A STABLE AIRMASS WILL RESIDE BELOW THE JET FOR A TIME
DURING WEDNESDAY MORNING.  WILL LEAVE THIS OUT OF THE TAF FOR NOW AS
ITS QUESTIONABLE WHETHER THE WIND SHEAR WILL BE MIXED TOGETHER WITH
WITH CONVECTIVE ACTIVITY.

OUTLOOK...
THURSDAY THROUGH SATURDAY...VFR.
SUNDAY...MOSTLY VFR WITH A CHANCE OF SHOWERS.

&&

.MARINE...
A DEPARTING HIGH PRESSURE AREA WILL PROVIDE THE AREA WITH TRANQUIL
CONDITIONS THROUGH TONIGHT AS A WARM FRONT APPROACHES FROM THE
WEST. SHOWERS AND POSSIBLY A THUNDERSTORM WILL MOVE IN ON WEDNESDAY
AHEAD OF A COLD FRONT.  WINDS WILL PICK UP DURING THE
AFTERNOON...WITH SMALL CRAFT CONDITIONS FOR LAKE ERIE IN THE
AFTERNOON AND EVENING.  SIMILAR CONDITIONS WILL PLAY OUT OVER LAKE
ONTARIO...ALTHOUGH SUSTAINED W-NW WINDS 15-20 KTS WILL CONTINUE
INTO THURSDAY.

HIGH PRESSURE WILL RETURN ON FRIDAY AND LAST INTO THE FIRST HALF OF
THE WEEKEND FOR A RETURN TO GOOD BOATING CONDITIONS.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM TO 10 PM EDT WEDNESDAY FOR
         LEZ020-040-041.
         SMALL CRAFT ADVISORY FROM 11 AM TO 10 PM EDT
         WEDNESDAY FOR LOZ030.
         SMALL CRAFT ADVISORY FROM 4 PM WEDNESDAY TO 6 PM EDT
         THURSDAY FOR LOZ042>045.
         SMALL CRAFT ADVISORY FROM 4 PM TO 10 PM EDT WEDNESDAY
         FOR SLZ022-024.

&&

$$

SYNOPSIS...ZAFF
NEAR TERM...ZAFF
SHORT TERM...WOOD
LONG TERM...TMA
AVIATION...ZAFF
MARINE...ZAFF