Area Forecast Discussion
Issued by NWS Buffalo, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS61 KBUF 230632
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
232 AM EDT WED APR 23 2014

.SYNOPSIS...
A SECONDARY COLD FRONT WILL SETTLE ACROSS THE REGION THIS MORNING
WITH SCATTERED RAIN SHOWERS AND DRIZZLE...THEN HIGH PRESSURE OVER
THE UPPER GREAT LAKES WILL DRIFT EAST AND CLEAR OUR SKIES DURING THE
AFTERNOON AND EVENING. WHILE IT WILL BE SEASONABLY COOL TODAY...MERCURY
LEVELS WILL STEADILY CLIMB DURING THE COURSE OF THE WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
LOW PRESSURE WILL DRIFT EAST ACROSS MAINE EARLY THIS MORNING WITH A
SURFACE TROUGH/SECONDARY COLD FRONT DROPPING ACROSS LAKE ONTARIO.
AREA RADARS SHOW AN AREA OF LIGHT RAIN SHOWERS EXTENDED ACROSS LAKE
ONTARIO PIVOTING SOUTH ACROSS THE SOUTHERN AND EASTERN LAKE SHORE
COUNTIES. FURTHER SOUTHWEST A NARROW BAND OF RAIN SHOWERS IS FOUND
EAST OF LAKE ERIE. THE PRECIPITATION AND OVERCAST SKIES WILL BE
ENHANCED BY AN UPSLOPE COMPONENT TO THE LOW LEVEL FLOW AS WINDS
BECOME NORTHWEST BEHIND THE SURFACE TROUGH.


WHILE PLENTY OF MOISTURE WILL BE IN PLACE BELOW 10K TO SUPPORT
SHOWER ACTIVITY...THE AIRMASS AT CLOUD LEVEL ACCORDING TO 00Z BUFKIT
PROFILES...WILL NOT BE COLD ENOUGH TO SUPPORT DENDRITIC CRYSTAL
GROWTH MOST LIKELY ONLY YIELDING SUPERCOOLED WATER DROPS AND PATCHY
DRIZZLE. HAVE REMOVED ALL MENTION OF SNOW FROM THE FORECAST THIS
MORNING DUE TO THE SNOW GROWTH ZONE BEING ORIENTED ABOVE THE LOW
LEVEL MOISTURE AND CLOUD TEMPS WARMER THAN -10C. IF ANY OF THIS
DRIZZLE FALLS IN POCKETS WHERE TEMPS DROP TO OR BELOW FREEZING THEN
THERE MAY BE A THREAT FOR PATCHY FREEZING DRIZZLE.

LATER TODAY...THE BASE OF THE SUPPORTING LONGWAVE TROUGH WILL EXIT ACROSS
NEW ENGLAND WHILE RIDGING WILL BUILD ACROSS THE MISSISSIPPI VALLEY
AND UPPER GREAT LAKES. WHILE THIS WILL EVENTUALLY LEAD TO CLEARING
SKIES FROM WEST TO EAST DURING THE COURSE OF THE MIDDAY AND
AFTERNOON...OVERCAST SKIES AND SOME LEFTOVER SHOWERS CAN BE EXPECTED
FOR THE MORNING.

THE GRADIENT AHEAD OF THE APPROACHING RIDGE WILL PROMOTE SOME GUSTY
WINDS AS WELL...WITH NORTHWEST WINDS AVERAGING 15 TO 30 MPH ACROSS
THE REGION. THESE WINDS WILL MAKE THE FRESH NEW CANADIAN AIRMASS
EVEN MORE NOTICEABLE...AS AFTERNOON TEMPS WILL NOT CLIMB OUT OF THE
40S IN MOST AREAS. THESE READINGS WILL BE ABOUT 10 DEG F BELOW
NORMAL VALUES.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...
WEDNESDAY NIGHT A MID LEVEL TROUGH AND SURFACE LOW ALONG THE NEW
ENGLAND COAST WILL SHIFT FARTHER EAST AND OUT TO SEA OVERNIGHT. ANY
REMAINING CLOUDS ACROSS THE NORTH COUNTRY DURING THE EVENING WILL
CLEAR. OTHERWISE A NARROW SURFACE RIDGE OVER THE CENTRAL LAKES WILL
BUILD EAST AND TOWARDS THE REGION OVERNIGHT. THE CLEARING SKIES AND
VERY CHILLY/DRY AIRMASS WILL ALLOW TEMPERATURES TO DROP OVERNIGHT.
EXPECT LOWS IN THE LOWER 30S ON THE LAKE PLAINS WITH MID 20S IN THE
COOLER SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO.

ON THURSDAY THE SURFACE HIGH WILL BUILD SLOWLY EAST ACROSS THE LOWER
LAKES WITH A CONTINUATION OF DRY WEATHER. EXPECT A GOOD DEAL OF
SUNSHINE AS WELL...WITH JUST SOME PASSING HIGH CLOUDS MAINLY ACROSS
WESTERN NY AS WARM ADVECTION AND SOME LIMITED MOISTURE INCREASE IN
THE MID AND UPPER LEVELS. THE AIRMASS WILL BEGIN TO MODERATE...AND
WITH SUNSHINE EXPECT HIGHS TO MAKE IT INTO THE MID 50S IN MOST AREAS
BY MID TO LATE AFTERNOON. A NORTHWEST GRADIENT ONSHORE FLOW WILL
KEEP AREAS ALONG BOTH THE LAKE ONTARIO AND LAKE ERIE SHORELINE
COOLER.

THURSDAY NIGHT WILL START DRY AND MAINLY CLEAR TO PARTLY CLOUDY WITH
JUST A FEW HIGH CLOUDS CROSSING THE REGION. BY LATE THURSDAY NIGHT A
LEAD SHORTWAVE AND SURFACE WARM OCCLUSION WILL APPROACH THE FAR
WESTERN END OF THE STATE. INCREASING LARGE SCALE ASCENT AND
CONVERGENCE ALONG THE FRONTAL ZONE WILL BRING THICKENING CLOUDS FROM
WEST TO EAST LATE...WITH A FEW SHOWERS POSSIBLY REACHING THE FAR
WESTERN END OF THE STATE BY DAYBREAK FRIDAY. TEMPERATURES WILL NOT
BE AS COOL AS WEDNESDAY NIGHT...BUT WILL STILL DROP INTO THE 30S IN
MOST AREAS. THESE LOWS WILL OCCUR DURING THE FIRST HALF OF THE
NIGHT...WITH INCREASING SOUTHEAST FLOW AND WARM ADVECTION ALLOWING
TEMPERATURES TO RISE LATE.

ON FRIDAY THE MID LEVEL TROUGH WILL SWING ACROSS SOUTHERN ONTARIO
WITH THE SURFACE OCCLUDED FRONT PUSHING QUICKLY FROM WEST TO EAST
ACROSS THE AREA. THE SURFACE FRONT WILL RACE OUT AHEAD OF THE UPPER
LEVEL SUPPORT...WHICH SHOULD ALLOW SHOWERS TO DECREASE IN COVERAGE
AND INTENSITY AS THEY PUSH EAST ACROSS THE AREA. LATEST SREF MEANS
ONLY SUPPORT A RELATIVELY LOW CHANCE OF MEASURABLE RAIN ON FRIDAY.
WITH THIS IN MIND...HAVE JUST GONE WITH LOWER CHANCE POPS FOR FRIDAY
MOVING FROM WEST TO EAST ACROSS THE AREA. EVEN IF THE SHOWERS
MATERIALIZE...THEY SHOULD BE BRIEF WITH PLENTY OF RAIN FREE TIME AS
WELL. A PUSH OF SOMEWHAT WARMER AIR WILL ARRIVE WITH THIS SYSTEM...
AND SHOULD SUPPORT HIGHS INTO THE MID 60S ACROSS LOWER ELEVATIONS
AWAY FROM THE LAKE SHORES.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE MODEL GUIDANCE CONTINUES TO STRUGGLE WITH THE SYNOPTIC
SCALE DETAILS FOR NEXT WEEKEND...WITH BOTH THE GFS AND ECMWF SHOWING
FAIRLY WIDE SWINGS FROM RUN TO RUN. GIVEN THE MODEL DISAGREEMENT...
THE BEST COURSE OF ACTION IS TO STAY FAIRLY CLOSE TO THE PREVIOUS
FORECAST UNTIL BETTER MODEL CONSISTENCY IS SEEN.

LOOKING IN MORE DETAIL...THE GFS REMAINS MUCH FARTHER SOUTH WITH A
STRONG MID LEVEL TROUGH FRIDAY NIGHT AND SATURDAY AS IT SWINGS
THROUGH THE GREAT LAKES AND NEW ENGLAND. THE GFS IS ALSO MUCH
STRONGER WITH A SURFACE REFLECTION. THE ECWMF IS FARTHER NORTH WITH
THE MID LEVEL TROUGH AND MUCH WEAKER WITH THE SURFACE SYSTEM...
ALTHOUGH IT WOULD STILL PRODUCE A FEW SHOWERS SATURDAY. THE GEFS
ENSEMBLE MEMBERS SHOW A VARIETY OF SOLUTIONS RANGING FROM THE
OPERATIONAL GFS AND OPERATIONAL ECMWF TO EVERYTHING IN BETWEEN. IN
SHORT...CONFIDENCE IS FAIRLY HIGH ON SOME SORT OF SYSTEM FOR
SATURDAY BUT THE TRACK AND INTENSITY IS STILL VERY UNCERTAIN. WITH
THIS IN MIND HAVE JUST KEPT POPS IN THE HIGH CHANCE RANGE.
TEMPERATURES WILL BEGIN TO PULL BACK ON SATURDAY...WITH THE CORE OF
THE COOL DOWN LIKELY TO ARRIVE SATURDAY NIGHT AND SUNDAY. BY THIS
TIME THE NEW 12Z ECMWF HAS MADE A DRAMATIC CHANGE TO PREVIOUS
FORECASTS AND BECOMES OUT OF PHASE WITH THE GFS AND MOST ENSEMBLE
MEMBERS. THE NEW ECMWF BECOMES MUCH LESS AMPLIFIED WITH ITS
NORTHEAST CONUS TROUGH...WHICH ALLOWS THE CENTRAL CONUS CUTOFF TO
GET CLOSE ENOUGH TO PRODUCE SHOWERS SUNDAY AND MONDAY. GIVEN THE
MAJOR CHANGE FROM PREVIOUS RUNS...WE WILL DISCARD THE 12Z ECMWF
SOLUTION AND KEEP SUNDAY AND MONDAY MAINLY DRY. SUNDAY WILL LIKELY
BE THE COOLEST DAY BEFORE SOME MODERATION EARLY NEXT WEEK ALTHOUGH
TEMPERATURES WILL STILL REMAIN BELOW AVERAGE.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AN AREA OF LOW PRESSURE WILL CONTINUE TO TRACK EAST ACROSS MAINE
WHILE AN ASSOCIATED SURFACE TROUGH/COLD FRONT PIVOTS SOUTH ACROSS
LAKE ONTARIO. THIS FRONT...ALONG WITH ABUNDANT LOW LEVEL
MOISTURE...WILL COMBINE TO PRODUCE WIDESPREAD MVFR CIGS ACROSS THE
REGION OVERNIGHT ALONG WITH SCATTERED SHOWERS AND DRIZZLE. IN
REGARDS TO CIGS...THEY WILL OSCILLATE BETWEEN IFR AND MVFR EAST OF
LAKE ONTARIO AND ALSO ACROSS THE HIGHER ELEVATIONS OF WRN NEW YORK.

AFTER 12Z...MVFR CIGS WILL GRADUALLY LIFT AND GIVE WAY TO VFR
CONDITIONS REGION-WIDE BY EARLY AFTERNOON AS HIGH PRESSURE WILL
BUILD ACROSS THE GREAT LAKES. THIS AREA OF HIGH PRESSURE WILL BRING
CLEAR SKIES FOR TONIGHT.

OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY...VFR.
FRIDAY THROUGH SUNDAY...VFR/MVFR. A CHANCE OF SHOWERS.

&&

.MARINE...
LOW PRESSURE WILL DRIFT ACROSS MAINE THIS MORNING BEFORE MAKING ITS
WAY ACROSS NOVA SCOTIA LATER TODAY WHILE HIGH PRESSURE OVER THE
MISSISSIPPI VALLEY WILL SLOWLY MOVE EAST. THE RELATIVELY TIGHT SFC
PRESSURE GRADIENT BETWEEN THE TWO SYSTEMS WILL PROMOTE MODERATE TO
FRESH NORTHWESTERLIES ON LAKES ERIE AND ONTARIO...RESULTING IN SMALL
CRAFT ADVISORIES FOR ALL OF THE NEW YORK NEARSHORE WATERS.

AS THE SFC HIGH DRIFTS ACROSS THE LOWER GREAT LAKES TONIGHT...WINDS
WILL WEAKEN WITH ADVISORIES EXPIRING FROM WEST TO EAST. LIGHT WINDS AND
NEGLIGIBLE WAVES WILL BE FOUND ON THE LOWER GREAT LAKES ON THURSDAY.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LEZ040-
         041.
         SMALL CRAFT ADVISORY UNTIL 11 AM EDT THURSDAY FOR
         LOZ043>045.
         SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
         LOZ042.

&&

$$

SYNOPSIS...RSH
NEAR TERM...RSH/SMITH
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...RSH/SMITH
MARINE...RSH/SMITH







USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.