Area Forecast Discussion
Issued by NWS Buffalo, NY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 051749
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
149 PM EDT THU MAY 5 2016

.SYNOPSIS...
AN UPPER LEVEL LOW WILL SLOWLY SPIRAL FROM THE CAROLINAS TONIGHT TO
NEW ENGLAND SATURDAY...WHILE MAINTAINING CHANCES FOR SHOWERS INTO
THE START OF THE WEEKEND. ANOTHER UPPER LEVEL LOW WILL APPROACH FROM
THE UPPER GREAT LAKES AND BRING ADDITIONAL RAIN SHOWERS TO THE
EASTERN GREAT LAKES REGION SATURDAY NIGHT. AIR TEMPERATURES WILL
WARM TO AND EXCEED NORMAL INTO SATURDAY...BEFORE A COLD FRONT
CROSSES THE REGION SATURDAY NIGHT RETURNING TEMPERATURES TO BELOW
NORMAL AGAIN.

&&

.NEAR TERM /THROUGH TONIGHT/...
THE UPPER LEVEL LOW CONTINUES TO DIVE SOUTHEASTWARD THIS
AFTERNOON...NOW NEARING THE CAROLINAS. REGIONAL RADARS SHOW A FEW
LIGHT AND WIDELY SCATTERED SHOWERS OVER WESTERN PORTIONS OF WNY...AND
THIS ACTIVITY IS EXPECTED TO EXPAND SOME....MAINLY OVER THE WESTERN
SOUTHERN TIER THIS AFTERNOON AS DAYTIME INSTABILITY INCREASES...AND
WEAK LOW LEVEL CONVERGENCE FROM A LINGERING INVERTED SFC TROUGH
REMAINS.

WITH 850 MB TEMPS RUNNING BETWEEN +2C AND +4C...EXPECT
HIGHS TO MAINLY BE IN THE UPPER 50S TODAY...WITH A FEW LOWER 60S IN
THE SLV. THE SOUTHERN LAKE ONTARIO SHORELINE WILL REMAIN IN THE
UPPER 40S WITH THE WIND COMING OFF THE COOL WATERS OF LAKE ONTARIO.

TONIGHT...THE CORE OF THE CLOSED LOW WILL SLIDE EAST TO THE
CAROLINA COASTLINE...WHILE SPURRING THE DEVELOPMENT OF ANOTHER
MODEST SURFACE LOW OFF THE DELMARVA COAST. THE BULK OF THE
LARGER-SCALE FORCING WITH THESE FEATURES WILL THUS AGAIN REMAIN
WELL TO OUR SOUTH AND EAST...WITH JUST SOME LIMITED SHORTWAVE
ENERGY CIRCULATING AROUND THE NORTHERN EDGE OF THE CLOSED LOW
AND BRUSHING SOUTHERN/CENTRAL NEW YORK STATE AT TIMES. IN
CONJUNCTION WITH THE LOSS OF HEATING...THIS SHOULD TRANSLATE
INTO A MAINLY DRY NIGHT FOR OUR REGION...WITH JUST A LOW CHANCE
FOR SOME ADDITIONAL SHOWERS FOUND ACROSS THE SOUTHERN TIER AND
INTERIOR SECTIONS OF THE FINGER LAKES. OTHERWISE EXPECT PARTLY
TO MOSTLY CLOUDY SKIES TO PREVAIL...WITH OVERNIGHT LOWS MAINLY
IN THE MID TO UPPER 40S.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
A TYPICAL SPRINGTIME...HIGHLY AMPLIFIED PATTERN WILL BE FOUND ACROSS
THE COUNTRY TO OPEN THIS PERIOD. LIKE A PAIR OF HEADLIGHTS STARING AT
YOU...DEEP TWIN CLOSED LOWS WILL BE FOUND ALONG EACH COAST WHILE
RIDGING WILL BE FOUND ACROSS THE NATIONS MID SECTION. THIS PATTERN
WILL BREAK DOWN DURING THE COURSE OF THE WEEKEND THOUGH...AS ENERGY
SPILLING OVER THE MACKENZIE MOUNTAINS IN THE YUKON WILL DIVE
SOUTHEAST ACROSS THE CANADIAN PRAIRIES TO THE GREAT LAKES BY SUNDAY.
THIS WILL DISRUPT THE UPPER LEVEL PATTERN OVER THE LOWER 48 BY
KICKING OUT THE ATLANTIC COAST CLOSED LOW WHILE ESTABLISHING A NEW
CLOSED CIRCULATION OVER EASTERN CANADA. THE COLD FRONT THAT WILL
LEAD THIS PATTERN CHANGE WILL END OUR BRIEF TASTE OF EARLY SUMMER
WEATHER SATURDAY NIGHT BY PLUNGING OUR REGION BACK TO A REGIME OF
BELOW NORMAL TEMPERATURES FOR SUNDAY AND MONDAY. THE DETAILS...

A BROAD CLOSED LOW CENTERED OVER NORTH CAROLINA FRIDAY MORNING WILL
SLOWLY DRIFT NORTH ACROSS THE DELMARVA PENINSULA DURING THE MIDDAY
AND AFTERNOON...WHILE SPOKES OF ENERGY AND PLENTY OF ATLANTIC BASED
MOISTURE WILL ROTATE BACK ACROSS NEW YORK STATE WITHIN THE RESULTING
DEEP EASTERLY FLOW. THIS WILL PROMOTE SCATTERED SHOWERS ACROSS MUCH
OF THE REGION AS WE WORK OUR WAY THROUGH THE DAY...ESPECIALLY OVER
THE FINGER LAKES REGION WHERE POPS HAVE BEEN RAISED TO LIKELY. AS
ONE WOULD EXPECT IN A MARINE BASED ERLY FLOW...THERE WILL NOT BE
ENOUGH INSTABILITY TO ADD ANY THUNDER TO THIS SHOWER ACTIVITY. ODDLY
ENOUGH...THE EASTERLY FLOW WILL ALSO INCLUDE SOME WARM ADVECTION
WITH H85 TEMPS NUDGING UP TO ARND 6C. DESPITE THE CLOUD COVER...THIS
SHOULD SUPPORT FAIRLY WIDESPREAD TEMPERATURES IN THE 60S FOR THE
AFTERNOON...ESPECIALLY ACROSS THE NORTH COUNTRY WHERE READINGS COULD
MAKE IT INTO THE UPPER 60S. THE EXCEPTION TO THE MILDER AIR WILL BE
ACROSS THE HIGHER TERRAIN OF THE SRN TIER.

THE CLOSED LOW WILL BRIEFLY STALL OVER EASTERN PENNSYLVANIA FRIDAY
NIGHT...WHILE FAIRLY DEEP ATLANTIC MOISTURE WILL REMAIN IN PLACE
OVER MUCH OF OUR FORECAST AREA. THIS WILL KEEP AT LEAST THE RISK FOR
SCATTERED SHOWERS IN PLACE...ESPECIALLY EARLY WHEN A LITTLE LEFTOVER
DIURNAL INSTABILITY WILL ASSIST EMBEDDED SHORTWAVES IN THE EASTERLY
FLOW.

ON SATURDAY...THE PERSISTENT UPPER LOW WILL GRADUALLY FILL WHILE
WEAK RIDGING WILL PUSH ACROSS THE LOWER GREAT LAKES. THIS...IN
COMBINATION WITH A LITTLE DRYING IN THE MID LEVELS...SHOULD ENABLE
PARTIAL SUNSHINE TO RETURN TO MUCH OF THE FORECAST AREA WITH MAINLY
DRY WEATHER ANTICIPATED. THE EXCEPTION COULD BE OVER THE FAR WESTERN
COUNTIES WHERE THE EFFECTS OF AN APPROACHING COLD FRONT COULD BE
EXPERIENCED BY DINNER TIME. OTHERWISE...SATURDAY SHOULD BE A FAIRLY
NICE DAY WITH A SURGE OF 8-10C H85 AIR AHEAD OF THE FRONT
ENCOURAGING TEMPERATURES TO PEAK IN THE 70S. THE GENESEE VALLEY AND
SOME OF THE SRN TIER VALLEYS COULD BE IN LINE FOR READINGS IN THE
MID AND EVEN UPPER 70S...PENDING THE AMOUNT OF SUN WE RECEIVE DURING
THE MIDDAY AND AFTERNOON. GIVEN THE WEAK SYNOPTIC FLOW...WEAK LAKE
BREEZES WILL KEEP AREAS WITHIN 5 MILES OR SO OF THE LAKES IN THE 50S
AND 60S.

THE COLD FRONT WILL MAKE ITS WAY ACROSS WESTERN AND NORTH CENTRAL
NEW YORK SATURDAY NIGHT. GIVEN THE WAVY NATURE OF THE FRONT (AS PER
THE PAST SEVERAL RUNS OF THE GFS AND ECMWF) AND SIGNIFICANT HGT
FALLS...HAVE RAISED POPS TO CATEGORICAL REGIONWIDE FOR SHOWERS AND
POSSIBLE THUNDERSTORMS. QPF FROM THIS FRONTAL PASSAGE IS FORECAST TO
RANGE FROM A QUARTER TO AT MOST A HALF INCH.

IN THE WAKE OF THE FRONT...IT WILL BE BREEZY AND NOTABLY COOLER ON
SUNDAY. H85 TEMPS ARE EXPECTED TO AVERAGE WITHIN A DEGREE OR SO OF
ZERO C...SO AFTERNOON TEMPERATURES ARE NOT EXPECTED TO CLIMB OUT OF
THE 50S. WHILE A BRIEF SHOWER CANNOT BE RULED OUT WITHIN THE CHILLY
CYCLONIC FLOW...SIGNIFICANT DRYING THE MID LEVELS AND RIDGING IN THE
LOW LEVELS SHOULD PRECLUDE THE DEVELOPMENT OF ANY ORGANIZED/
WIDESPREAD SHOWERS.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WHILE CONFIDENCE IN THE LOW LEVEL FEATURES WILL BE LOWER THAN NORMAL
DURING THIS PERIOD...CONSISTENCY BETWEEN THE GEFS AND ECMWF
ENSEMBLES WITH THE OVERLYING JET LEVEL PATTERN WILL SUPPORT
RELATIVELY HIGH CONFIDENCE WITH THE TEMPERATURE TREND. THIS WILL
INCLUDE NEAR TO ABOVE NORMAL MERCURY READINGS.

RIDGING OVER THE LOWER GREAT LAKES ON MONDAY WILL SUPPLY OUR
FORECAST AREA WITH FINE WEATHER...AS AMPLE SUNSHINE WILL HELP TO
SEND AFTERNOON TEMPERATURES INTO THE LOW-MID 60S FOR MOST AREAS.

THE RIDGE IS FORECAST TO FLATTEN OVER THE REGION MONDAY NIGHT WITH
FAIRLY STRONG WARM ADVECTION BECOMING ESTABLISHED. THIS COULD SET
THE STAGE FOR SOME SHOWERS MONDAY NIGHT...ALTHOUGH A HIGHER CHANCE
FOR PCPN WILL COME ON TUESDAY WHEN THE A TROUGH WILL DIG ACROSS
QUEBEC AND SOUTHERN ONTARIO.

AS THE TROUGH PUSHES EAST ACROSS THE ST LAWRENCE VALLEY LATE TUESDAY
NIGHT AND WEDNESDAY...LOW LEVEL RIDGING SHOULD ONCE AGAIN TAKE HOLD
ACROSS THE LOWER GREAT LAKES TO PROMOTE FAIR WEATHER.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AT 18Z A NORTHEAST WIND IS SENDING A LOW DECK OF MVFR CLOUDS OFF
LAKE ONTARIO...WITH THE CLOUDS FROM KIAG TO ABOUT KROC. OTHERWISE
MAINLY VFR FLIGHT CONDITIONS ARE FOUND THIS AFTERNOON. A FEW SHOWERS
ARE POSSIBLE...WITH GREATEST CHANCES ACROSS THE WESTERN SOUTHERN
TIER WHERE THERE IS EVEN A CHANCE FOR A THUNDERSTORM WITH LIMITED
INSTABILITY. WILL MAINTAIN CONTINUITY AT KJHW AND CONTINUE WITH A
VCTS...THOUGH CONFIDENCE FOR SUCH THUNDERSTORM OVER THE AIRFIELD...OR
NEAR THE AIRFIELD WILL REMAIN LOW.

TONIGHT AS THE UPPER LEVEL LOW FOCUSES UPON THE SOUTHEAST AND MID-
ATLANTIC COASTLINE WE SHOULD SEE A REDUCTION IN CLOUDS...WITH VFR
FLIGHT CONDITIONS FROM TONIGHT THROUGH THE FIRST HALF OF TOMORROW.

OUTLOOK...

FRIDAY AFTERNOON...VFR/MVFR WITH SCATTERED TO NUMEROUS
SHOWERS...WITH THE GREATEST AREAL COVERAGE EXPECTED ACROSS INTERIOR
PORTIONS OF THE SOUTHERN TIER AND FINGER LAKES.
SATURDAY...VFR.
SATURDAY NIGHT...SHOWERS WITH A CHANCE OF THUNDERSTORMS. IFR/MVFR
SUNDAY...MAINLY VFR WITH A CHANCE OF MORNING SHOWERS EAST OF
KROC/KDSV.
MONDAY...VFR.
MONDAY NIGHT AND TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.

&&

.MARINE...
THE REMAINDER OF THE WEEK WILL FEATURE A RELATIVELY WEAK PRESSURE
GRADIENT ACROSS THE LOWER LAKES REGION. THIS WILL RESULT IN LIGHT
TO MODEST WINDS PREDOMINATING...ALONG WITH CORRESPONDINGLY MINIMAL
WAVES.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...THOMAS
NEAR TERM...JJR/THOMAS
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...THOMAS
MARINE...JJR



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