FXUS61 KBOX 061746
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
146 PM EDT SAT SEP 6 2008
.SYNOPSIS...
A TROPICAL STORM WARNING CONTINUES FOR PORTIONS OF SOUTHEAST NEW ENGLAND.
THIS SYSTEM WILL BRING HEAVY RAINFALL...SOME FLOODING AND THE
POTENTIAL FOR A PERIOD OF STRONG WINDS TO PORTIONS OF THE COASTAL
PLAIN TONIGHT. WARM...DRY WEATHER WILL FOLLOW FOR MOST OF SUNDAY AND
MONDAY. AN APPROACHING COLD FRONT TUESDAY MAY BRING A PERIOD OF
SCATTERED SHOWERS/THUNDERSTORMS FOLLOWED BY DRY SEASONABLE WEATHER
WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SCATTERED AND /MAINLY/ LIGHT SHOWERS EXPECTED FOR MOST OF THIS
AFTERNOON ACROSS THE AREA. AT NOON TODAY THE LEADING EDGE OF THE
RAINS DIRECTLY ASSOCIATED WITH HANNA HAD WORKED TO THE WESTERN CT
STATE LINE...BUT WILL LIKELY TAKE A FEW HOURS TO WORK ITS WAY
EASTWARD INTO LOWER CT RIVER VALLEY. LIKELY/CATEGORICAL POPS BEGIN
THERE AROUND 4 PM...PROGRESSING TO NORTHEAST MA AROUND 6 TO 7 PM.
LOW CLOUD COVER IS EXPECTED TO PERSIST THIS AFTERNOON ACROSS THE
MAJORITY OF THE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
***THE TROPICAL STORM WATCH HAS BEEN UPGRADED TO A TS WARNING FOR THE
RI AND MASSACHUSETTS COASTAL REGIONS INCLUDING THE ISLANDS***
THE TRACK CONTINUES TO POINT TOWARD RI/SOUTHEAST MASS EAST OF THE
BOSTON-PROVIDENCE CORRIDOR WITH PASSAGE OF THE STORM CENTER AROUND
09Z EARLY SUNDAY MORNING. HEAVY DOWNPOURS SHOULD CONTINUE THROUGH
MUCH OF THE NIGHT AS THE STORM APPROACHES. PRECIPITABLE WATER VALUES
ARE FORECAST TO REBOUND TO 2.5 INCHES SO EXPECT HEAVY DOWNPOURS OVER
SEVERAL HOURS. THIS POINTS TO HEAVY RAIN/FLOODING BEING ONE PROBLEM.
THE STORM CENTER ITSELF IS EXPECTED TO MAINTAIN A CORE WIND OF 45
KNOTS GUSTING TO 55 KNOTS AS IT PASSES. TROPICAL STORMS REACHING OUR
LATITUDE NORMALLY HAVE THE STRONG WINDS TO THE EASTERN SIDE OF THE
STORM. THIS WOULD POINT TO TROPICAL STORM FORCE WINDS ALONG MUCH OF
OUR SOUTH COAST AND POSSIBLY A LITTLE WAY NORTH THROUGH THE OUTER
CAPE AND THE CAPE COD BAY COAST. WITH THE OPEN WATER TO THE EAST...WE
COULD SEE SOME TS WINDS FARTHER NORTH. BUFKIT SOUNDINGS FROM THE GFS
SHOW 50 KNOT WINDS LESS THAN 1000 FEET OFF THE DECK. MEANWHILE...THE
CORE WILL BE CLOSE TO INTERIOR SOUTHEAST NEW ENGLAND...ESPECIALLY SE
MASS AND NORTHERN RI.
WITH ALL THIS IN MIND...THE TROPICAL STORM WATCH FOR COASTAL AREAS
WILL BE UPGRADED TO A WARNING. ALSO...THE TROPICAL STORM WIND WATCH
WILL BE UPGRADED TO A WARNING AND EXPANDED TO INCLUDE SOUTHEAST
MIDDLESEX /NEAR BOSTON/ AND SOUTHERN WORCESTER COUNTY. MOST OF THE
WIND ASSOCIATED WITH THESE HEADLINES WILL TAKE PLACE BETWEEN
MIDNIGHT AND 8 AM SUNDAY.
WE PROBABLY WILL NOT SEE WIND GUSTS EXCEED 30 OR 40 MPH TO THE
NORTHWEST OF THE TRACK. HOWEVER...THE HEAVY RAIN AND BEST
PROBABILITY OF FLOODING WILL EXIST TO THE NORTHWEST OF THE TRACK.
MODELS IN PRETTY GOOD AGREEMENT THAT A TOTAL OF 3 TO 6 INCHES OF
RAIN WILL FALL ACROSS PORTIONS OF THIS REGION. THEREFORE...FLOOD
WATCHES HAVE BEEN ISSUED AND PLEASE SEE OUR HYDROLOGY SECTION. THE
MAIN THREAT WILL BE FOR URBAN FLOODING...ESPECIALLY SINCE THIS
AMOUNT OF RAIN MAY FALL IN A VERY SHORT PERIOD OF TIME. IN
ADDITION...ISOLATED THUNDERSTORMS WILL BE POSSIBLE WITH THIS SYSTEM.
THE OTHER THING WE ARE GOING TO HAVE TO WATCH FOR IS THE POTENTIAL
FOR ISOLATED WEAK TORNADOES. TROPICAL SYSTEMS SOMETIMES PRODUCE
THEM ON THEIR NORTHERN AND EASTERN SECTIONS OF THE STORM WHERE SHEAR
VALUES BECOME QUITE HIGH. BASED ON OUR CURRENT TRACK...THE RISK FOR
THIS WOULD BE ON THE COASTAL PLAIN.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
SUNDAY...MOST OF THE EFFECTS FROM HANNA WILL BE FINISHED BY SUNDAY
MORNING. STRONG WINDS...ESPECIALLY ACROSS THE COASTAL WATERS AND
THE IMMEDIATE COAST WILL CONTINUE THROUGH THE MORNING AND THEN
GRADUALLY DIMINISH THROUGH THE AFTERNOON. IN ADDITION...THERE MAY
BE A FEW LINGERING SHOWERS...ESPECIALLY ACROSS THE NORTHEASTERN
PORTIONS OF SOUTHERN NEW ENGLAND THROUGH MID MORNING. AS HANNA OR
HER REMNANTS MOVE OFF TO THE NORTHEAST...HIGH PRESSURE WILL BUILD IN
BEHIND. COULD TURN OUT TO BE QUITE A NICE DAY...WITH HIGHS AROUND
80 AND SKIES CLEARING THROUGH THE DAY.
MONDAY AND TUESDAY...HIGH PRESSURE REMAINS IN CONTROL UNTIL AN UPPER
LEVEL TROUGH AND ACCOMPANYING LOW PRESSURE SYSTEM PULL A COLD FRONT
THROUGH SOUTHERN NEW ENGLAND ON TUESDAY. SCATTERED SHOWERS AND
THUNDERSTORMS WILL LIKELY ACCOMPANY THE FRONT AS IT MOVES THROUGH.
HIGH TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL.
WEDNESDAY AND THURSDAY...HIGH PRESSURE BUILDS BACK INTO THE AREA
BEHIND THE FRONT. DRY...MORE AUTUMN-LIKE WEATHER IS EXPECTED...WITH
HIGH TEMPERATURES SLIGHTLY BELOW NORMAL.
FRIDAY...ANOTHER COLD FRONT APPROACHES FROM THE WEST. THIS FAR
OUT...TIMING IS DEFINITELY A QUESTION.
OVERALL MADE FEW MAJOR CHANGES TO THE GRIDS BEYOND TUESDAY. MAINLY
BLENDED THE CURRENT FORECAST WITH MOSGUIDE WHERE POSSIBLE TO FOCUS
ON THE NEARER TERM.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
REST OF TODAY AND TONIGHT....MVFR/IFR CONDITIONS WILL LINGER THE
REMAINDER OF THIS AFTERNOON. ANOTHER AREA OF HEAVY RAIN WILL MOVE IN
TONIGHT BRINGING IFR/LIFR CONDITIONS. SOUTHEAST WINDS AT FMH...HYA
AND ACK WILL INCREASE TO 35 KNOTS WITH GUSTS 45 TO 50 KNOTS BETWEEN
03Z AND 10Z. BRIEF GUSTS TO 35 OR 40 KT POSSIBLE AT KPVD AND KBOS
DURING THAT TIMEFRAME. THE CENTER WILL PASS ACROSS INTERIOR SOUTHEAST
MASS AROUND 09Z...THEN WINDS WILL SHIFT TO NORTHWEST APPROACHING 12Z.
SUNDAY...TEMPO MVFR CEILINGS 015-030 HND FT EASTERN TERMINALS WITH A
FEW LINGERING SHOWERS POSSIBLE UNTIL 15Z. OTHERWISE VFR CONDITIONS
WITH WINDS DIMINISHING BY AFTERNOON.
OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY
SUNDAY NIGHT AND MONDAY...VFR.
TUESDAY...MAINLY VFR...THEN MVFR IN SHOWERS AND THUNDERSTORMS AS A
FRONT MOVES THROUGH SOUTHERN NEW ENGLAND.
WEDNESDAY AND THURSDAY...VFR.
&&
.MARINE...
TODAY...SOUTHERLY SWELL IN ADVANCE OF TROPICAL STORM HANNA WILL
BUILD SEAS THROUGH TODAY. SOUTH WINDS WILL REMAIN 10-15 KNOTS MUCH
OF THE DAY...THEN INCREASE TOWARD EVENING AS TS HANNA APPROACHES.
TONIGHT...TROPICAL STORM HANNA LOOKS TO TRACK ACROSS COASTAL RI AND
SOUTHEAST MASSACHUSETTS. THIS WILL BRING TROPICAL STORM CONDITIONS TO
THE WATERS WITH 50 KNOT GUSTS AND SEAS OVER 10 FEET FROM MIDNIGHT TO
6 AM.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY...WINDS AND SEAS WILL START THE PERIOD WITH GALE OR NEAR GALE
FORCE WIND GUSTS ESPECIALLY ACROSS THE NORTHEASTERN COASTAL WATERS.
WINDS WILL GRADUALLY DIMINISH THROUGH THE DAY. HOWEVER...SEAS
BETWEEN 5 AND 10 FEET IN THE EASTERN COASTAL WATERS AND 8 TO 12 FEET
IN THE SOUTHERN COASTAL WATERS WILL CONTINUE. SEAS WILL GRADUALLY
DECREASE LATE SUNDAY EVENING.
MONDAY...WINDS WILL HAVE DECREASED BELOW SMALL CRAFT CRITERIA BY THE
END OF THE DAY WITH SEAS REMAINING AROUND 5 FEET ACROSS THE OUTER
COASTAL WATERS THROUGH THE AFTERNOON.
TUESDAY...SMALL CRAFT CRITERIA LIKELY AS UPPER LEVEL TROUGH AND COLD
FRONT MOVE THROUGH THE WATERS.
WEDNESDAY AND THURSDAY...WINDS AND WAVES WILL REMAIN BELOW SMALL
CRAFT CRITERIA.
&&
.HYDROLOGY...
FIRST RAIN BAND FROM LATE LAST NIGHT/EARLY THIS MORNING BROUGHT HEAVY
RAINS PRIMARILY TO SOUTHEAST MASSACHUSETTS AND RHODE ISLAND. IN THAT
AREA RAINFALL TOTALS RANGED FROM 2 TO 3.5 INCHES.
THERE WILL BE A QUIET PERIOD FOR A FEW HOURS THIS AFTERNOON WITH SOME WHICH
SCATTERED SHOWERS AND TSTMS. THE SECOND AND MORE SUBSTANTIAL RAIN
PERIOD WILL START LATE THIS AFTERNOON/EARLY THIS EVENING AS TS HANNA
APPROACHES UP THE COAST. HEAVY DOWNPOURS FROM AROUND 5 PM THROUGH 5
AM WILL BRING POTENTIAL 3 TO 6 INCH RAINFALL WITH LOCALLY HEAVIER
AMOUNTS POSSIBLE.
WE WILL CONTINUE THE FLASH FLOOD WATCH. FOR THE MAJORITY OF THE
AREA...FLOOD GUIDANCE IS 3 INCHES IN 1 HOUR...4.5 INCHES IN 3 HOURS.
URBAN CENTERS WILL NOT NECESSARILY NEED THIS MUCH RAIN TO CAUSE
FLOODING.
DURING THIS TIME OF YEAR...RIVERS TEND TO RUN AT LOWER LEVELS...THEY
CAN TAKE IN A GOOD DEAL OF RAIN. BUT GIVEN AMOUNT OF RAIN FORECAST
MINOR FLOODING COULD OCCUR ON SOME OF THE LARGER TRIBUTARIES.
&&
.TIDES/COASTAL FLOODING...
GFS MRPSSE IS ONLY SHOWING A HALF TO 1 FOOT STORM SURGE ACROSS THE
SOUTH COAST LATE SUNDAY NIGHT. HOWEVER...FEEL IT COULD BE
SIGNIFICANTLY UNDERDONE SINCE BUFKIT IS SHOWING THE POTENTIAL FOR 50
TO 60 MPH WIND GUSTS IN THE WARM SECTOR. ASTRONOMICAL TIDES ARE NOT
THAT HIGH...BUT STILL SEE THE POTENTIAL FOR A 3 FOOT STORM SURGE.
THIS MAY RESULT IN SOME MINOR COASTAL FLOODING ALONG THE SOUTH COAST
AT THE TIME OF HIGH TIDE. WE ARE NOT EXPECTING ANY COASTAL FLOODING
ON THE EASTERN MA COAST.
THE TIMES OF HIGH TIDE ARE AS FOLLOWS...
BOSTON 516 AM SUNDAY
NANTUCKET 633 AM SUNDAY
NEWPORT 127 AM SUNDAY
PROVIDENCE 140AM SUNDAY
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR CTZ002>004.
TROPICAL STORM WIND WARNING UNTIL 8 AM EDT SUNDAY FOR
CTZ002>004.
MA...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR MAZ002>024-026.
TROPICAL STORM WARNING FOR MAZ007-015-016-019>024.
TROPICAL STORM WIND WARNING UNTIL 8 AM EDT SUNDAY FOR MAZ005-
006-012>014-017-018.
NH...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR NHZ011-012-015.
RI...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR RIZ001>008.
TROPICAL STORM WARNING FOR RIZ002-004>008.
TROPICAL STORM WIND WARNING UNTIL 8 AM EDT SUNDAY FOR RIZ001-
003.
MARINE...TROPICAL STORM WARNING FOR ANZ230>237-250-254-255.
&&
$$
SYNOPSIS...RLG
NEAR TERM...NMB
SHORT TERM...WTB/NMB
LONG TERM...RLG
AVIATION...WTB/STRAUSS/RLG
MARINE...WTB/RLG
HYDROLOGY...
TIDES/COASTAL FLOODING...
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