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 282020
AFDBUF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
420 PM EDT SUN SEP 28 2014

.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN THROUGH MONDAY BUT WILL STILL BRING DRY
WEATHER AND A GOOD DEAL OF SUNSHINE. AN UPPER LEVEL DISTURBANCE MAY
PRODUCE A FEW WIDELY SCATTERED SHOWERS ON TUESDAY BEFORE DRY WEATHER
RETURNS FOR MIDWEEK. TEMPERATURES WILL REMAIN ABOVE AVERAGE THROUGH
THE UPCOMING WEEK. A STRONG COLD FRONT WILL THEN CROSS THE REGION ON
FRIDAY WITH A GOOD CHANCE OF SHOWERS FOLLOWED BY MUCH COOLER
TEMPERATURES FOR NEXT WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
SATELLITE IMAGERY SHOWING PATCHES OF CIRRUS DRIFTING FROM SOUTHWEST
TO NORTHEAST ACROSS THE REGION AS UPPER LEVEL DIVERGENCE AND
MOISTURE INCREASE AHEAD OF A WEAK MID LEVEL TROUGH MOVING OUT OF THE
OHIO VALLEY AND INTO THE LOWER LAKES. THIS MID LEVEL TROUGH WILL
SLOWLY CROSS THE REGION TONIGHT AND BRING MORE CIRRUS AND MID LEVEL
CLOUDINESS TO THE AREA. EXPECT SKIES TO AVERAGE PARTLY CLOUDY FOR
THE NIGHT ALTHOUGH THERE WILL BE A FEW BRIEF INTERVALS OF MOSTLY
CLOUDY SKIES. LATER TONIGHT CLOUDS SHOULD THIN ACROSS THE WESTERN
SOUTHERN TIER. THIS SHOULD ALLOW FOR ENOUGH RADIATIONAL COOLING TO
PRODUCE TYPICAL VALLEY FOG ONCE AGAIN...WITH THE MOST WIDESPREAD FOG
ALONG THE UPPER ALLEGHENY AND UPPER GENESEE RIVERS AND THEIR
TRIBUTARIES.

THE CIRRUS CLOUDS WILL ONLY SLIGHTLY INHIBIT RADIATIONAL COOLING.
EXPECT LOWS TO BE IN THE MID 50S ON THE LAKE PLAINS WITH MID TO
UPPER 40S IN THE COOLER INTERIOR SOUTHERN TIER AND TUG HILL REGION.

ON MONDAY THE SOUTHERN TIER VALLEY FOG WILL BURN OFF BY 15Z. THE
WEAK MID LEVEL TROUGH WILL DRIFT EAST INTO NEW ENGLAND AND THE MID
ATLANTIC BY LATE AFTERNOON...TAKING THE BULK OF THE UPPER LEVEL
DIVERGENCE AND MOISTURE WITH IT. EXPECT MID/HIGH CLOUDS TO GRADUALLY
DECREASE FROM WEST TO EAST. THERE WILL BE SOME INCREASE IN LOW LEVEL
MOISTURE ACROSS THE SOUTHERN TIER AND WESTERN FINGER LAKES AND THIS
MAY ALLOW SOME CUMULUS TO DEVELOP DURING THE AFTERNOON ACROSS THE
HIGHER TERRAIN. DESPITE THE PASSING MID/HIGH CLOUDS AND CUMULUS
STILL EXPECT MUCH OF THE TIME TO BE MOSTLY SUNNY. THE NAM STILL
INSISTS ON DEVELOPING SCATTERED DEEP MOIST CONVECTION ACROSS THE
SOUTHERN TIER AND WESTERN FINGER LAKES LATE MONDAY AFTERNOON. IT
APPEARS THE NAM IS FAR TOO AGGRESSIVE IN POOLING LOW LEVEL MOISTURE
IN THIS AREA...AND THUS HAS FAR TOO MUCH DIURNAL INSTABILITY IN THE
MODEL. THIS SOLUTION HAS LITTLE OR NO SUPPORT FROM OTHER OPERATIONAL
GUIDANCE AND MOST SREF MEMBERS...SO HAVE KEPT THE FORECAST DRY.

THE WEAK MID LEVEL TROUGH WILL DROP 850MB TEMPS BY A DEGREE OR TWO
ON MONDAY OVER RECENT DAYS...BUT STILL EXPECT HIGHS IN THE UPPER 70S
ACROSS LOWER ELEVATIONS AND MID 70S ACROSS HIGHER TERRAIN AND THE
NORTH COUNTRY. LIGHT SYNOPTIC SCALE FLOW AND STRONG DIFFERENTIAL
HEATING WILL AGAIN ALLOW LOCAL LAKE BREEZES TO FORM DURING THE
AFTERNOON WITH ONSHORE FLOW KEEPING THE IMMEDIATE LAKESHORES COOLER.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
AN UPPER LEVEL SHORTWAVE TROUGH AND ATTENDANT WEAK SURFACE LOW WILL
IMPACT THE REGION DURING THIS TIMEFRAME. THE SHORTWAVE ALOFT WILL
BECOME A CLOSED UPPER LOW AS PASSES ACROSS THE LOWER GREAT
LAKES...WHICH WILL HELP TO SPIN UP A WEAK LOW PRESSURE PRESSURE
SYSTEM ALONG A SLOWING COLD FRONT. ALBEIT LIGHT...THIS MAY BRING
THE FIRST PRECIPITATION TO THE AREA IN A ABOUT A WEEK.

THE AREA SHOULD REMAIN DRY MONDAY NIGHT AHEAD OF THE AFOREMENTIONED
APPROACHING UPPER SHORTWAVE AND SURFACE COLD FRONT. THE SHORTWAVE
WILL CLOSE OFF INTO AN UPPER LOW TUESDAY AS IT MOVES SOUTHEASTWARD
FROM THE CENTRAL LAKES TO SOUTHERN NEW ENGLAND BY LATE IN THE DAY
WEDNESDAY...WHILE A WEAKENING SURFACE COLD FRONT HANGS UP ACROSS
SOUTHERN NEW YORK STATE DURING THE DAY ON TUESDAY. AS THE UPPER LOW
CLOSES OFF...IT WILL AID IN THE SPIN UP OF WEAK LOW PRESSURE ALONG
WHAT IS LEFT OF THE NOW DIFFUSE FRONTAL BOUNDARY THAT IS DRAPED
ACROSS THE SOUTHERN NEW YORK STATE. WILL GO WITH LOW CHANCE POPS AS
IT APPEARS THAT THERE MAY BE JUST ENOUGH MOISTURE AND LIFT WITH THE
COMBINATION OF THESE TWO FEATURES TO BRING A FEW LIGHT SHOWERS TO
THE REGION LATER TUESDAY MORNING THROUGH TUESDAY EVENING. THOUGH
COVERAGE IS EXPECTED TO BE SPARSE...THE BEST CHANCE FOR SHOWERS WILL
BE ACROSS THE SOUTHERN TIER...WHICH WILL BE CLOSEST TO THE UPPER LOW
AND IN THE VICINITY OF THE SURFACE BOUNDARY. THOUGH UNLIKELY...THERE
MAY BE JUST ENOUGH INSTABILITY FOR AN ISOLATED THUNDERSTORM TUESDAY
AFTERNOON/EVENING AS WELL. THE UPPER LOW WILL MOVE OFF THE SOUTHERN
NEW ENGLAND COAST WEDNESDAY NIGHT...ALLOWING UPPER RIDGING AND
SURFACE HIGH PRESSURE TO BUILD ACROSS THE AREA. THIS WILL END ANY
SHOWER ACTIVITY AND ALLOW FOR A DECREASE IN CLOUD COVER ACROSS THE
REGION. EVEN THOUGH COOLER AIR FILTERING INTO THE REGION COMBINED
WITH SOME ADDED CLOUD COVER WILL HELP TO HOLD TEMPS DOWN A
BIT...STILL EXPECT HIGHS IN THE UPPER 60S TO NEAR 70 TUESDAY...WITH
LOWER 70S BY WEDNESDAY. THIS IS STILL A BIT ABOVE AVERAGE FOR LATE
SEPTEMBER. LOWS BOTH NIGHTS WILL BE IN THE LOWER TO MID 50S.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
THURSDAY WILL BE THE NICEST DAY OF THIS PERIOD AS AN UPPER RIDGE
CRESTS ACROSS THE AREA...WHILE STRONG CANADIAN SURFACE HIGH PRESSURE
NOSES SOUTHWARD ACROSS NEW YORK STATE...WHICH WILL KEEP CONDITIONS
DRY ACROSS THE AREA. AS THE SURFACE HIGH SHIFTS EAST...WINDS WILL
BECOME MORE SOUTHEASTERLY. THIS COMBINED WITH STRONG SUBSIDENCE
ALOFT WILL HELP BOOST TEMPS A FEW MORE NOTCHES INTO THE LOWER TO MID
70S. THE UPPER RIDGE AND SURFACE HIGH PRESSURE WILL SHIFT EAST OF
THE AREA THURSDAY NIGHT...AS A SIGNIFICANT UPPER LEVEL TROUGH BEGINS
TO APPROACH THE REGION FROM THE UPPER GREAT LAKES. THE 12Z GFS/ECMWF
ARE EVEN A BIT FASTER THAN THE PREVIOUS 00Z RUNS...BUT STILL IN
PRETTY GOOD AGREEMENT ON THE MOVEMENT AND AMPLITUDE OF THE UPPER
LEVEL TROUGH...AND BOTH TAKE A STRONG SURFACE LOW FROM THE VICINITY
OF THE UPPER LAKES FRIDAY...ALMOST DUE NORTH NORTHEAST TO JAMES BAY
BY EARLY SATURDAY. THOUGH THERE IS STILL ABOUT A SIX HOUR DIFFERENCE
IN TIMING...IT APPEARS THE STRONG SURFACE COLD FRONT ASSOCIATED WITH
THE LOW WILL SWEEP ACROSS THE REGION SOMETIME BETWEEN MIDDAY FRIDAY
AND EARLY SATURDAY MORNING. THIS LOOKS TO BE OUR FIRST CHANCE AT
SEEING WIDESPREAD MEASURABLE PRECIPITATION ACROSS THE REGION IN
QUITE SOME TIME. IF THE GFS IS CORRECT...THERE APPEARS TO BE
FAVORABLE DYNAMICS FOR THE POSSIBILITY OF SOME STRONG WIND GUSTS
WITH THE FRONT. HOWEVER THE ECMWF DOES NOT SHOW THESE SAME
DYNAMICS...SO WILL KEEP THUNDER OUT OF THE GRIDS FOR NOW BEING THIS
FAR OUT.

THE EARLIER TIMING WILL ALLOW FOR CLOUDS AND POSSIBLE SHOWERS TO
MOVE INTO THE REGION BY FRIDAY AFTERNOON...KEEPING TEMPERATURES A
BIT COOLER THAN PREVIOUSLY THOUGHT YESTERDAY...WITH HIGHS NOW IN THE
UPPER 60S TO LOWER 70S...AS GUSTY SOUTHEASTERLY WINDS TURN MORE
SOUTHWESTERLY DURING THE AFTERNOON JUST AHEAD OF THE FRONT. HIGHS
SATURDAY WILL DROP SOME 10 TO 15 DEGREES AS MUCH COOLER AIR FILTERS
INTO THE REGION BEHIND THE SURFACE COLD FRONT...WITH HIGHS IN THE
UPPER 50S TO LOWER 60S. LOW THURSDAY NIGHT WILL BE HELD UP IN THE
50S THANKS TO SOUTHERLY FLOW AHEAD OF THE APPROACHING COLD
FRONTAL BOUNDARY. COLDER AIR WILL BEGIN TO FILTER IN FRIDAY
NIGHT...WITH LOWS IN THE UPPER 40S TO LOWER 50S.

HIGHLY AMPLIFIED UPPER TROUGH WILL BUILD INTO THE NORTHEAST FOR THE
REMAINDER OF THE UPCOMING WEEKEND...ALONG WITH MUCH COOLER AIR. A
STRONG SHORTWAVE WILL ROTATE THROUGH THE BASE OF THE DEEP LONGWAVE
TROUGH LATER SATURDAY INTO SUNDAY. THIS COMBINED WITH WRAP AROUND
MOISTURE ON THE BACK SIDE OF THE LOW WILL KEEP THE THREAT OF AT
LEAST SOME SCATTERED SHOWERS AROUND DURING THIS TIMEFRAME. 850MB
TEMPS WILL FALL TO AROUND 0C TO -2C...WILL MAKE IT TOUGH FOR HIGH
TEMPS TO GET OUT OF THE 50S ON SUNDAY ACROSS THE AREA...WHILE LOWS
SATURDAY NIGHT FALL BACK INTO THE 40S.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE SURFACE AND ALOFT CONTINUES TO PROVIDE VFR THIS
AFTERNOON WITH JUST A FEW HIGH/THIN CIRRUS DRIFTING ACROSS THE AREA.
CIRRUS AND MID LEVEL CLOUDINESS WILL THICKEN A LITTLE TONIGHT FROM
SOUTHWEST TO NORTHEAST AS A WEAK UPPER LEVEL DISTURBANCE MOVES OUT
OF THE OHIO VALLEY AND ACROSS THE LOWER GREAT LAKES. THE CLOUDS
APPEAR LIKELY TO THIN AGAIN LATER TONIGHT ACROSS THE SOUTHERN
TIER...AND THIS SHOULD ALLOW FOR ENOUGH RADIATIONAL COOLING TO
PRODUCE TYPICAL SOUTHERN TIER VALLEY FOG WITH LOCAL VLIFR LATE
TONIGHT AND MONDAY MORNING. SOME OF THIS MAY IMPACT KJHW.

ON MONDAY THE VALLEY FOG WILL BURN OFF BY MID TO LATE MORNING. THIS
WILL LEAVE VFR TO PREVAIL WITH CIRRUS AND MID LEVEL CLOUDS
DECREASING FROM WEST TO EAST. INCREASING LOW LEVEL MOISTURE MAY
ALLOW SOME CUMULUS TO DEVELOP DURING THE AFTERNOON ACROSS THE HIGHER
TERRAIN OF THE SOUTHERN TIER AND WESTERN FINGER LAKES WITH BASES
AROUND 4K FEET.

OUTLOOK...
TUESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.
WEDNESDAY THROUGH THURSDAY...VFR EXCEPT FOR SOUTHERN TIER VALLEY FOG
WITH LOCAL IFR EACH LATE NIGHT AND EARLY MORNING.
FRIDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.

&&

.MARINE...
HIGH PRESSURE WILL CONTINUE TO PROVIDE LIGHT WINDS AND FLAT WAVE
ACTION THROUGH MONDAY. A LIGHT SYNOPTIC SCALE FLOW AND STRONG
DIFFERENTIAL HEATING WILL ALLOW LAKE BREEZES TO DEVELOP AGAIN MONDAY
AFTERNOON WITH WINDS BECOMING ONSHORE ALONG ALL THE LAKESHORES. A
WEAK BACKDOOR COLD FRONT WILL DROP SOUTH ACROSS THE LOWER LAKES
MONDAY NIGHT. THIS WILL BRING A BRIEF PERIOD OF MODERATE NORTHEAST
WINDS ON LAKE ONTARIO WITH CHOPPY WAVE ACTION ALONG THE SOUTH
SHORE...BUT CONDITIONS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.

LIGHT WINDS WILL THEN RETURN FOR TUESDAY THROUGH THURSDAY BEFORE A
STRONG AREA OF LOW PRESSURE MOVES INTO THE GREAT LAKES BY FRIDAY...
PRODUCING A PERIOD OF STRONGER WINDS ACROSS THE LOWER LAKES.

&&

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

&&

$$

SYNOPSIS...HITCHCOCK
NEAR TERM...HITCHCOCK
SHORT TERM...JM
LONG TERM...JM
AVIATION...HITCHCOCK
MARINE...HITCHCOCK






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