FXUS61 KBOX 032228
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
525 PM EST THU DEC 3 2009
.SYNOPSIS...
HIGH PRESSURE WILL PREVAIL ACROSS THE REGION INTO SATURDAY WITH
SEASONABLY COOL WEATHER. LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST
U.S. COAST...AND MAY COME CLOSE ENOUGH TO GIVE LIGHT SNOWS FOR SOME
PORTIONS OF INTERIOR SOUTHERN NEW ENGLAND SATURDAY NIGHT INTO SUNDAY
MORNING. A WEAK COLD FRONT MAY BRING A QUICK ROUND OF PRECIPITATION
MONDAY NIGHT. ANOTHER POTENTIALLY STRONGER LOW MAY DEVELOP ACROSS
THE GREAT LAKES...WHICH MAY BRING MORE SUBSTANTIAL PRECIPITATION
AROUND THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
STRONG LOW PRESSURE OVER NOVA SCOTIA CONTINUES TO TRACK EAST.
DRY WESTERLY FLOW PREVAILS ACROSS THE AREA. A STRATOCUMULUS
DECK FORMED ACROSS THE INTERIOR THIS AFTERNOON IN RESPONSE TO
COOLING TEMPERATURES ALOFT AND STEEPENING LOW LEVEL LAPSE RATES.
CLOUDS ACROSS THE INTERIOR ARE EXPECTED TO DIMINISH TONIGHT WITH
THE LOSS OF DAYTIME HEATING. WINDS ARE ALSO EXPECTED TO DIMINISH
ALLOWING FOR RADIATIONAL COOLING. TEMPERATURES ARE ONLY EXPECTED
TO FALL BACK INTO THE 30S TO THE LOWER 40S IN THE URBAN CENTERS
AND EXPOSED COASTAL LOCATIONS...AS ONLY WEAK SURFACE HIGH PRESSURE
CRESTS OVER SOUTHERN NEW ENGLAND.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY...MOSTLY CLEAR SKIES...SEASONABLY MILD CONDITIONS EXPECTED AS
WEAK SURFACE HIGH PRESSURE PREVAILS. USED A BLEND OF MAV/MET MOS
GUIDANCE WHICH YIELDS HIGHS IN THE UPPER 40S TO MID 50S.
FRIDAY NIGHT...INCREASING HIGH CLOUDS EXPECTED AHEAD OF A DEVELOPING
H25 JET STREAK AND AHEAD OF SURFACE LOW PRESSURE FORMING OFF THE MID
ATLANTIC COAST. A DRY AND COOL NIGHT EXPECTED...BUT WITH LOWS ABOVE
SEASONAL NORMS.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
UPPER LEVEL PATTERN CHANGE ACROSS NORTH AMERICA CONTINUES...WITH
LONG WAVE RIDGE BUILDING ACROSS THE EASTERN PACIFIC INTO ALASKA AND
A LARGE LONG WAVE TROUGH DIGGING IN THE CENTRAL U.S. HOWEVER...THIS
PATTERN TRIES TO FLATTEN OUT INTO THE WEEKEND WHILE THE TROUGH
REPOSITIONS FURTHER W. THE UPPER FLOW BECOMES MORE ZONAL OVER THE
EASTERN U.S. EARLY NEXT WEEK...THEN THE WESTERN TROUGH TRIES TO
MIGRATE E BY LATE NEXT WEEK. RATHER BUSY PATTERN IN PLACE...WITH THE
POTENTIAL FOR TWO ROUNDS OF SNOW OR MIXED PRECIP FOR THE REGION. A
LOT OF UNCERTAINTY IN PLACE...THOUGH...WITH A WIDE RANGE OF MEDIUM
RANGE MODEL SUITE SOLUTIONS ESPECIALLY LATE IN THE PERIOD.
SATURDAY...LOW PRES DEVELOPS OFF THE SOUTHEAST U.S. COAST AND WORKS
UP THE WESTERN ATLC IN THE SW UPPER FLOW. CLOUDS WILL CONTINUE
ACROSS THE REGION AS NE FLOW FRESHENS IN RESPONSE TO THE APPROACHING
LOW. WILL BRING IN CHANCE POPS INTO THE S COAST BY MIDDAY...THEN
PUSH SLOWLY N TO NEAR THE MASS PIKE BY NIGHTFALL.
NOT A LOT OF AGREEMENT WITH THE LOW TRACK. LEANED TOWARD THE 00Z OP
ECMWF SOLUTION...WHICH WAS IN THE CENTER OF THE SOLUTION ENVELOPE.
SEVERAL MODELS DO SHOW MOISTURE WORKING INTO THE REGION AS WELL...SO
A LITTLE BETTER CONFIDENCE THAT PRECIP WILL PUSH INTO THE REGION.
RAIN MAY START TO MIX WITH OR CHANGE TO SNOW ACROSS THE HIGHER
TERRAIN OF SW NH/E SLOPES OF THE BERKS LATE IN THE DAY.
SATURDAY NIGHT-SUNDAY...LOW PRESSURE WELL SE OF NANTUCKET MAKES ITS
CLOSEST APPROACH LATE SAT NIGHT. KEPT SOME CONTINUITY FROM THE
PREVIOUS FORECAST...BLENDING WITH THE 00Z ECMWF. THIS BRINGS LIKELY
POPS INTO E MA/RI SATURDAY NIGHT...WITH CHANCE POPS ALL THE WAY TO
THE NY BORDER.
BIG QUESTION AT THIS POINT WILL BE ANY MIXED PRECIP OR SNOW. MODEL
PARTIAL THICKNESSES DO INDICATE SOME SNOW ACROSS INLAND AREAS. ALSO
USED A BLEND OF THE PREVIOUS FORECAST AND THE METNAM MOS GUIDANCE
FOR OVERNIGHT LOWS...WITH KEEP SOMEWHAT MILDER TEMPS ALONG THE COAST
WITH THE INCREASING ONSHORE FLOW. WITH THE CURRENT FORECAST...HAVE
FORECASTED UP TO AN INCH OF SNOW POSSIBLE...MAINLY ACROSS THE HIGHER
TERRAIN. NOT GOING TO GET A WHOLE LOT DUE TO LESS PRECIP REACHING
FAR INLAND AREAS.
EXPECT PRECIP TO TAPER OFF SUNDAY AS THE LOW PUSHES WELL OUT OF SEA
AND HIGH PRES BUILDS OUT OF THE OHIO VALLEY. TEMPS WILL TOP OF CLOSE
TO SEASONAL NORMS.
MONDAY-TUESDAY...WITH THE FAST UPPER FLOW...HIGH PRESSURE WILL
QUICKLY MOVE S OF NEW ENGLAND. A WEAK LOW AND ASSOCIATED COLD FRONT
IN THE UPPER FLOW WILL ZIP ACROSS THE NORTHERN TIER STATES MONDAY
NIGHT AND TUESDAY. HAVE CHANCE POPS IN THE ZONES AND GRIDS FOR
MONDAY NIGHT AND EARLY TUESDAY...MAINLY N OF THE MASS PIKE. MAY BE
ENOUGH QPF TO GIVE SOME AREAS A LIGHT COATING OF SNOW...MAINLY NEAR
OR N OF ROUTE 2. SHOULD SEE CLEARING BY MIDDAY.
TUESDAY NIGHT-THURSDAY...A LOT OF QUESTIONS IN PLACE WITH DEVELOPING
LOW PRESSURE DURING THIS TIMEFRAME. ENERGY OUT OF THE GULF OF MEXICO
APPEARS TO DEVELOP THIS LOW ACROSS THE GREAT LAKES OR OHIO VALLEY
/DEPENDING UPON WHICH MODEL ONE BELIEVES/ THEN MOVES ACROSS THE
REGION. INTERESTING TO NOTE THAT THE 12Z OP ECMWF SOLUTION CAME IN
SOMEWHAT CLOSE TO THE 12Z OP GFS RUN...THOUGH THERE ARE SOME
DIFFERENCES. BOTH DEVELOP LOW PRES AROUND THE LAKES...WITH A LOT OF
ISENTROPIC LIFT SETTING UP AS A WARM FRONT FORMS OFF THE MID ATLC.
HAVE PUT IN CHANCE POPS FOR THIS TIME...BUT HAVE LOW CONFIDENCE WITH
THIS SOLUTION...ALONG WITH ITS BRINGING SNOWS INTO THE REGION
WED-THU.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
REMAINDER OF THIS AFTERNOON...GUSTY WINDS WILL CONTINUE TO DIMINISH.
VFR WITH CIGS 040-050 ACROSS INTERIOR CT/MA AND SOUTHWEST NH.
TONIGHT...
VFR WITH LOW PROBABILITY OF CIGS 020-030 ACROSS THE HIGHER TERRAIN OF
CT/MA AND SOUTHWEST NH. WEST WINDS WILL OCCASIONALLY GUSTS TO 25 KT.
FRIDAY...
VFR WITH LIGHT WEST WINDS BACKING TO THE SOUTHWEST LATE.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY AND SATURDAY NIGHT...STARTING OFF WITH VFR CIGS ESPECIALLY
ACROSS N MA/S NH...BUT WILL QUICKLY LOWER TO MVFR-IFR CIGS/VSBYS
FROM S-N. RAIN MOVES INTO S COAST...THEN WILL PUSH N SAT NIGHT. MAY
SEE LOCAL IFR CIGS/VSBYS IN RAIN AND/OR SNOW ESPECIALLY ACROSS
INLAND AREAS...BUT NOT CERTAIN OF HOW MUCH OF A VSBY RESTRICTION
COULD OCCUR WELL INLAND WITH ANY SNOW. EXPECT MAINLY RAIN FROM
KBOS-KHYA-KACK AND THE ISLANDS. N GUSTS 25-35 KT POSSIBLE CC AND
THE ISLANDS SAT NIGHT.
SUNDAY...LOCAL MVFR CIGS/VSBYS IN LEFTOVER -SHRA/-SHSN
EARLY...OTHERWISE VFR.
MONDAY...VFR. CIGS DOWN TO ABOUT 5KFT DURING THE AFTERNOON ACROSS S
NH/W MA.
MONDAY NIGHT-TUESDAY...LOCAL MVFR CIGS/VSBYS IN RAIN AND/OR SNOW
SHOWERS MAINLY NEAR OR N OF THE MASS PIKE LATE MON NIGHT INTO EARLY
TUE...THEN IMPROVING TO VFR.
&&
.MARINE...
TONIGHT...A SMALL CRAFT ADVISORY CONTINUES FOR LEFTOVER S SWELL
DUE TO STRONG SOUTHERLY WINDS EARLIER TODAY. SCATTERED WESTERLY
WIND GUSTS TO 25 TO 30 KT EXPECTED THIS EVENING AS DRIER AIR USHERS
IN ACROSS THE WATERS. WINDS DIMINISHING OVERNIGHT.
FRIDAY...A SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS WILL PERSIST
ACROSS THE OUTER WATERS. SEAS WILL GRADUALLY SUBSIDE.
FRIDAY NIGHT...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FOR A TIME
ACROSS THE OUTER SE WATERS. SEAS WILL CONTINUE TO SUBSIDE.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY AND SATURDAY NIGHT...LOW PRESSURE WILL PASS WELL SE OF
NANTUCKET LATE SATURDAY NIGHT OR EARLY SUNDAY. COULD SEE N GALE
FORCE GUSTS ON THE EASTERN AND SOUTHERN OUTER WATERS...WITH SMALL
CRAFT WINDS AND SEAS LIKELY FOR THE REMAINING WATERS.
SUNDAY...N-NW WINDS DIMINISHING DURING THE DAY. WIND GUSTS UP TO
25-30 KT MAINLY IN THE MORNING. SEAS WILL REMAIN AT OR ABOVE 5
FT..MAINLY ON THE OUTER WATERS THROUGH SUNDAY NIGHT.
MONDAY...EXPECT WINDS AND SEAS BELOW SMALL CRAFT CRITERIA...BUT SW
GUSTS MAY APPROACH 25 KT ON THE OUTER WATERS LATE.
TUESDAY...SMALL CRAFT CRITERIA WINDS AND SEAS PROBABLE.
&&
.CLIMATE...
EARLIER ISSUANCES OF THE LSR TODAY INDICATED LOGAN AIRPORT WITH A
WIND GUST TO 60 MPH AT 508 AM. THIS IS INCORRECT. A CORRECTED LSR
WAS ISSUED AT 1235 PM INDICATING A REVISED WIND GUST FOR LOGAN...
WHICH WAS 49 MPH AND OCCURRED AT 804 AM.
BOSTON/S LOGAN AIRPORT HAS NOT FALLEN TO THE FREEZING MARK SO FAR
THIS SEASON. THE RECORD LATEST IN THE SEASON THAT BOSTON HAS
RECORDED ITS FIRST 32F WAS DEC 2ND 1975. AS OF TODAY...THIS RECORD
HAS BEEN BROKEN. AVERAGE FIRST DATE OF 32 IN BOSTON IS AROUND
NOVEMBER 4TH. CURRENT FORECAST SUGGESTS THAT THE MINIMUM AT LOGAN
MAY NOT FALL TO BELOW FREEZING UNTIL SUNDAY NIGHT/EARLY MONDAY
MORNING.
RECORD HIGH TEMPERATURES HAVE BEEN BROKEN TODAY...AND RECORD HIGH
MINS ARE IN JEOPARDY AT BOS...PVD...AND BDL.
THE RECORDS AT OUR FOUR CLIMATE SITES FOR THIS DATE ARE AS
FOLLOWS:
MAX T HIGH MIN
BOS...65 IN 1932 48 IN 1932
PVD...63 IN 1932 46 IN 1998*
BDL...64 IN 1932 43 IN 1932
ORH...61 IN 1932 47 IN 1998
MQE...61 IN 1950 AND 1932
*MEANS RECORD NOTED ALSO SET IN PREVIOUS YEARS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST FRIDAY FOR ANZ232>235-
237-250-251-254>256.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ230-
231-236.
&&
$$
SYNOPSIS...STRAUSS/EVT
NEAR TERM...STRAUSS
SHORT TERM...STRAUSS
LONG TERM...EVT
AVIATION...NOCERA/STRAUSS/EVT
MARINE...STRAUSS/EVT
CLIMATE...STAFF
