FXUS61 KBOX 092315
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
615 PM EST WED DEC 9 2009
.SYNOPSIS...
LOW PRESSURE WILL PUSH AWAY FROM SOUTHERN NEW ENGLAND TONIGHT.
BLUSTERY AND COLD WEATHER WILL FOLLOW THURSDAY THROUGH THIS
WEEKEND. A WARM FRONT MAY APPROACH FROM THE SOUTH ON MONDAY. A
PERIOD OF RAIN AND OR SNOW SHOWERS MAY OCCUR TUESDAY IN
ASSOCIATION WITH LOW PRESSURE.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
A LINE OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WERE RAPIDLY
MOVING ACROSS THE REGION EARLY THIS EVENING...MAINLY SOUTH OF THE MA PIKE.
THE UNUSUAL SCATTERED DECEMBER THUNDERSTORMS WERE BEING CAUSED BY
A STRONG SHORTWAVE DISTURBANCE COMBINED WITH 500 MB WINDS CLOSE TO 130 KNOTS.
THAT TREMENDOUS WIND SHEAR ALONG WITH THE MARGINAL INSTABILITY IS
ENOUGH FOR SOME SCATTERED CONVECTION. WITH THE COLD AIR ALOFT
NUMEROUS REPORTS OF SMALL HAIL WILL OCCUR WITH THE ACTIVITY. A FEW
ISOLATED REPORTS OF HALF INCH TO DIME SIZE HAIL CAN NOT BE RULED OUT.
THE SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WERE MOVING QUITE
QUICKLY ACROSS THE REGION WITH THE STRONG WINDS ALOFT. THE
PRECIPITATION SHOULD COME TO AN END ACROSS THE EASTERN SECTIONS BETWEEN
8 AND 10 PM AND THE REST OF THE NIGHT WILL BE DRY.
&&
.SHORT TERM /MIDNIGHT THROUGH 6 PM THURSDAY/...
THURSDAY...A TROUGH WILL CROSS THE AREA DURING THE LATE AFTERNOON OR
EVENING. THIS WILL BRING MUCH COLDER AIR TO THE REGION. MOISTURE IS
FAIRLY LIMITED...BUT COULD SEE SCATTERED SNOW SHOWERS OR FLURRIES
PARTICULARLY THE INTERIOR HIGH TERRAIN WHERE SOME LAKE MOISTURE WILL
BE AVAILABLE.
TEMPS ARE BASICALLY THE 4AM FCST SINCE 12Z GUIDANCE WAS GENERALLY
SIMILAR.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
MEDIUM RANGE MODELS APPEAR IN FAIRLY GOOD AGREEMENT THROUGH THIS
WEEKEND...THEN START TO SHOW SOME DIVERGENCE IN THEIR SOLUTIONS...
EXHIBITING TROUBLE IN HANDLING POSSIBLE INTERACTION BETWEEN THE
NORTHERN AND SOUTHERN STREAMS ACROSS THE CONUS AFTER THE
WEEKEND...WHICH LENDS TO LOWER CONFIDENCE ON THIS PORTION OF THE
FORECAST.
THURSDAY NIGHT THROUGH MONDAY...
WITH THE STRONG LOW LEVEL JET AS WELL AS COLD AIR ADVECTION WORKING
ACROSS THE NORTHEASTERN U.S. OUT OF CENTRAL CANADA...APPEARS THAT IT
WILL BE A COLD AND BLUSTERY TIME FROM THURSDAY NIGHT THROUGH AT
LEAST SATURDAY. WITH THE STRONG W TRAJECTORY ACROSS LAKE ONTARIO AND
POSSIBLY TAPPING INTO THE LAKES UPSTREAM...APPEARS THAT THERE WILL
BE A STRONG LAKE EFFECT EVENT ACROSS A GOOD PORTION OF CENTRAL NY
STATE WHICH WILL LIKELY REACH ACROSS THE BERKSHIRES INTO THE E
SLOPES AND SW NH. FOR NOW...HAVE CARRIED SLIGHT CHANCE TO LOW
CHANCE POPS FOR SNOW SHOWERS...BUT WOULD NOT BE TOTALLY SURPRISED
TO SEE MORE THAN THIS...MAINLY ACROSS THE HIGHER TERRAIN OF THE
MONADNOCKS AND BERKS THURSDAY NIGHT AND FRIDAY.
THE COLDEST AIR WILL MOVE ACROSS THE REGION ON FRIDAY AS HIGHS
STRUGGLE TO THE MID 30S ACROSS E MA...BUT WILL REMAIN NEAR OR BELOW
FREEZING FOR MOST OTHER AREAS. THIS COMBINED WITH THE STRONG
WINDS...WHICH MAY REACH WIND ADVISORY CRITERIA ON CAPE COD AND THE
ISLANDS...WILL YIELD WIND CHILL READINGS IN THE SINGLE DIGITS AND
TEENS. VERY FRIGID CONSIDERING HOW MILD IT HAS BEEN OVER THE LAST
SEVERAL WEEKS. TEMPS WILL REBOUND A FEW DEGS ON SATURDAY...BUT WILL
STILL FEEL VERY COLD WITH THE CONTINUED STRONG WINDS.
WINDS FINALLY START TO RELAX SATURDAY NIGHT AS HIGH PRES BUILDS
ACROSS THE NORTHEAST...THOUGH HIGHS WILL REMAIN IN THE 30S.
MODEL SOLUTIONS START TO DIVERGE BY SUNDAY. HAVE BROUGHT CHANCE POPS
INTO N CT/RI/SE MA AS A WARM FRONT MAY APPROACH FROM THE S...THOUGH
NOT A LOT OF CONFIDENCE WITH THIS. CONTINUED INTO SUNDAY
NIGHT...THEN KEPT SLIGHT CHANCE POPS AS A FRONT MAY APPROACH FROM
THE W MONDAY.
MONDAY NIGHT THROUGH WEDNESDAY...
LITTLE AGREEMENT IN THE MODELS THROUGH THE END OF THE EXTENDED
FORECAST PERIOD. THE ONE THING THAT THERE IS SOME SENSE OF AGREEMENT
ON IS THE POTENTIAL FOR A LOW PRESSURE SYSTEM AFFECTING SOUTHERN NEW
ENGLAND TUESDAY. THE DISCREPANCY COMES IN THE ORIGINS OF THE LOW
PRESSURE SYSTEM AND THE TIMING. THESE DIFFERENCES MAY AFFECT THE
TYPE OF PRECIP THAT OCCURS. SUFFICE IT TO SAY THERE WILL BE A PERIOD
OF RAIN AND/OR SNOW SOMETIME IN THE PERIOD FROM MONDAY NIGHT THROUGH
WEDNESDAY MORNING. AT THIS POINT IT LOOKS LIKE TEMPERATURES EARLY
NEXT WEEK WILL RUN RIGHT AROUND NORMAL FOR MID DECEMBER.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
THROUGH THIS EVENING...
GENERALLY EXPECT IFR CONDITIONS TO PERSIST INTO THE EVENING WITH
PLENTY OF LOW CLOUDS...LIGHT RAIN/DRIZZLE. ALSO NOTING AREAS OF
DENSE FOG FORMING OVER THE NEW BLANKET OF SNOW ACROSS E MA...WHICH
SHOULD TEND TO DISSIPATE AS COLDER AIR WORKS IN.
TONIGHT...IFR CONDITIONS SHOULD IMPROVE TO VFR BY LATE EVENING AS
GUSTY WEST TO SOUTHWEST WINDS BRING IN DRIER AIR TO THE REGION.
THURSDAY...GENERALLY VFR CONDITIONS EXPECTED DESPITE GUSTY WEST
WINDS. HOWEVER...SCATTERED TO EVEN BROKEN STRATO-CUMULUS CLOUDS
BETWEEN 3 AND 5 THOUSAND FEET SHOULD DEVELOP ESPECIALLY IN THE
INTERIOR.
OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
THURSDAY NIGHT-FRIDAY...VFR. AREAS MVFR IN -SHSN ACROSS THE E SLOPS
OF THE BERKSHIRES INTO SW NH. W WIND GUSTS UP TO 35-40 KT AT TIMES
MAINLY NEAR THE S COAST. COULD SEE MECHANICAL LLWS/TURBULENCE.
FRIDAY NIGHT-SATURDAY NIGHT...VFR.
SUNDAY...VFR. LOCAL MVFR CIGS/VSBYS IN SCT RAIN/SNOW SHOWERS MAINLY
ACROSS RI/SE MA.
MONDAY...VFR. MAY SEE WIDELY SCT RAIN/SNOW SHOWERS SUNDAY
NIGHT-MONDAY AS A WEAK FRONT APPROACHES.
&&
.MARINE...
TONIGHT THROUGH THURSDAY...OCCASIONAL GALE FORCE GUSTS. PLEASE SEE
MWW FOR DETAILS. SEAS ARE IN THE CWF BUT AT 4PM ARE 12-18 FEET IN
THE OPEN WATERS E OF MA.
OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
THURSDAY NIGHT THROUGH SATURDAY...WITH CONTINUED COLD AIR ADVECTION
OVER THE RELATIVELY WARMER WATERS...EXPECT GALE FORCE WINDS TO
CONTINUE THROUGH THIS PERIOD. GUSTS COULD REACH 40-45 KT MAINLY ON
THE OPEN WATERS. SEAS WILL REMAIN UP TO 10-14 FEET ON THE SOUTHERN
OUTER WATERS.
SATURDAY NIGHT...WINDS WILL FINALLY START TO DIMINISH...THOUGH GUSTS
COULD REACH 30 KT. SEAS WILL ALSO SLOWLY SUBSIDE BUT REMAIN UP TO 6
TO 8 FT ON THE OUTER WATERS.
SUNDAY...W WINDS BACK TO SW AND CONTINUE TO DIMINISH. SEAS SLOWLY
SUBSIDE BUT REMAIN AT OR ABOVE 5 FT.
MONDAY...WINDS SHIFT TO N-NW. GUSTS UP TO 30 KT POSSIBLE.
&&
.HYDROLOGY...
MAINSTEM RIVERS ARE EXPECTED TO REMAIN WITHIN THEIR BANKS. PAWTUXET
IN RI AT CRANSTON WILL BE MONITORED BUT EXPECTED TO REMAIN BELOW FS.
&&
.TIDES/COASTAL FLOODING...
MINOR COASTAL FLOODING MAY OCCUR AROUND THE TIME OF HIGH TIDE
THROUGH AROUND 6 PM OR SO. HAVE CONTINUED THE ADVISORY FOR THE EAST
FACING COASTLINES THROUGH 7 PM.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...COASTAL FLOOD ADVISORY UNTIL 7 PM EST THIS EVENING FOR MAZ007-
014>016-019-022.
NH...NONE.
RI...NONE.
MARINE...GALE WARNING FROM 1 AM THURSDAY TO 5 AM EST FRIDAY FOR
ANZ230>237-250-251-254>256.
&&
$$
SYNOPSIS...DRAG/EVT
NEAR TERM...FRANK/EVT
SHORT TERM...DRAG
LONG TERM...EVT/RLG
AVIATION...FRANK/EVT/DRAG
MARINE...DRAG/NOCERA/EVT
HYDROLOGY...DRAG
TIDES/COASTAL FLOODING...DRAG
