Area Forecast Discussion
Issued by NWS Boston, MA

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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KBOX 281800 AFDBOX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 200 PM EDT THU AUG 28 2014 .SYNOPSIS... A COLD FRONT MOVES OFFSHORE THIS MORNING. HIGH PRESSURE BUILDS IN WITH DRIER WEATHER AND LESS HUMIDITY FOR TODAY AND FRIDAY. HURRICANE CRISTOBAL WILL PASS WELL OFFSHORE TODAY BRINGING DANGEROUS SURF AND RIP CURRENTS TO SOUTH FACING OCEAN BEACHES OF RI AND MA. PLEASANT LATE SUMMER WEATHER WILL CONTINUE ON SATURDAY. A FRONT WILL SLOWLY MOVE ACROSS NEW ENGLAND LATE SUNDAY AND MONDAY BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
200 PM UPDATE... FORECAST REMAINS ON TRACK FOR THIS AFTERNOON. TEMPERATURES ARE HEATING UP QUICKLY ACROSS THE REGION AS WE JUST TOPPED OUT AT 84F BY 200 PM. TEMPS HAVE WARMED A FEW DEGREES MORE SO THEN FORECASTED THANKS TO EXCELLENT MIXING UP TO 850 MB. THIS HAS ALLOWED GUSTY WINDS THIS AFTERNOON...REACHING 20-25 MPH. SOME LINGERING MOISTURE AT AROUND 850MB HAS ALLOWED FOR DIURNAL CU TO DEVELOP THIS AFTERNOON. FINALLY...DEWPOINTS CONTINUE TO DROP MAKING IT A VERY COMFORTABLE DAY. PREVIOUS DISCUSSION... HURRICANE CRISTOBAL WILL PASS ABOUT 375 MILES SOUTHEAST OF NANTUCKET TODAY. TROPICAL STORM FORCE WINDS ONLY EXTEND ABOUT 205 MILES OUT FROM THE STORM. SWELLS ALREADY TRANSMITTED NORTH THROUGH THE OCEAN...NOTING A 13-15 SECOND PERIOD OBSERVED ON BOTH THE SOUTHERN AND EASTERN WATERS...AND A 7 FOOT HEIGHT HAS BEEN OBSERVED AT THE BUOY SOUTHEAST OF BLOCK ISLAND. WAVE MODEL DATA SHOWS A 7-8 FOOT SWELL LINGERING ON OUR SOUTHERN EXPOSED WATERS THROUGH THE DAY AND THEN DIMINISHING TONIGHT. CALCULATIONS SUGGEST BREAKERS OF 6-12 FEET ON SOUTH- FACING OCEAN BEACHES. WE WILL CONTINUE THE HIGH SURF ADVISORY AND EXTEND IT THROUGH EARLY FRIDAY.
-- End Changed Discussion --
&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... TONIGHT...HIGH PRESSURE BUILDS OVER THE REGION AND SHOULD BRING DIMINISHING WIND WITH DECOUPLING IN THE INTERIOR. DEWPOINTS WILL FALL TO 45-55 MOST AREAS. THIS WILL ALLOW TEMPERATURES INLAND TO FALL TO THE UPPER 40S AND 50S. OCEAN INFLUENCE WILL KEEP COASTAL AREAS AROUND 60 OR LOW 60S. FRIDAY... HIGH PRESSURE SURFACE AND ALOFT BUILDS OVERHEAD. THIS WILL MEAN FAIR SKIES AND LIGHT WINDS...AS WELL AS SEABREEZES ALONG THE COASTS. TEMPS ALOFT 8-10C SHOULD SUPPORT MAX TEMPS IN THE 70S. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... OVERVIEW AND MODEL PREFERENCES... MEDIUM RANGE MODELS AND ENSEMBLES CONTINUE TO SIGNAL SURFACE AND UPPER LEVEL RIDGING EARLY IN THIS PERIOD...THEN TREND TOWARD A FLATTENING OF THE UPPER PATTERN ACROSS THE NORTHERN TIER STATES MAINLY LATE THIS WEEKEND INTO EARLY NEXT WEEK. NOTING TIMING ISSUES WITH SURFACE FEATURES BEYOND MONDAY WITH THE FASTER FLOW ALOFT. ENSEMBLES IN THE LATER PERIODS APPEAR TO BE HANDLING THESE FEATURES THOUGH LOWER CONFIDENCE FOR THE MONDAY-WEDNESDAY TIMEFRAME DUE TO THE TIMING ISSUES. USED A BLEND OF AVAILABLE GUIDANCE THROUGH MONDAY...WHICH SHOWED GOOD CONSISTENCY TO PREVIOUS FORECASTS...THEN LEANED TOWARD THE EC/GFS ENSEMBLES BEYOND MONDAY. DETAILS... FRIDAY NIGHT THROUGH SATURDAY NIGHT... SURFACE AND UPPER LEVEL RIDGING TAKES OVER DURING THIS TIMEFRAME... WITH THE BEST CONDITIONS EXPECTED SATURDAY WITH DRY AND SEASONABLE CONDITIONS. EXPECT E-W ORIENTED HIGH PRES RIDGE ACROSS SOUTHERN NEW ENGLAND AS WINDS BECOME MORE SOUTHERLY LATER SAT AND SAT NIGHT. THIS RIDGE WILL HOLD OFF THE APPROACH OF THE NEXT FRONTAL SYSTEM...KEEPING DRY CONDITIONS THROUGH SAT NIGHT. HIGHS ON SAT WILL BE CLOSE TO SEASONABLE NORMALS /IN THE 70S/. WILL SEE PATCHY FOG DEVELOP LATE BOTH NIGHTS...FIRST WITH LIGHT/VRBL WINDS FRI NIGHT THEN BECOMING S BY SAT NIGHT WHICH WILL BRING IN SOME MORE LOW LEVEL MOISTURE. UPPER LEVEL RIDGE STARTS TO BREAK DOWN DURING SAT NIGHT...SO WILL NOT ONLY SEE HUMIDITY INCREASE BUT TEMPS BE SEVERAL DEGS MILDER SAT NIGHT AS COMPARED TO FRI NIGHT. FRI NIGHT LOWS WILL BE MAINLY IN THE 50S...THEN IN THE LOWER-MID 60S SAT NIGHT. SUNDAY THROUGH MONDAY NIGHT... A ILL DEFINED WARM FRONT WILL CROSS THE REGION EARLY SUNDAY...BRINGING WARM AND MORE HUMID CONDITIONS AS S-SW WINDS TAKE OVER. THIS WILL ALSO USHER IN A ROUND OF SCT SHOWERS/THUNDERSTORMS ESPECIALLY SUN AFTERNOON/EVENING WITH BETTER INSTABILITY. WITH A FLATTER...NEARLY ZONAL UPPER LEVEL FLOW SUNDAY NIGHT...NOTING ANOTHER FRONT TRYING TO SINK S OUT OF SOUTHERN QUEBEC/ONTARIO. APPEARS THIS FRONT WILL STALL ACROSS NORTHERN NEW ENGLAND...UNTIL AN H5 SHORT WAVE MOVES OUT OF THE GREAT LAKES ALONG THIS FRONT. THIS WILL BE FOCUS OF SHOWER/TSTM ACTIVITY ESPECIALLY SUNDAY NIGHT INTO MONDAY...WITH BEST SHOT FOR CONVECTION EARLY SUN EVENING THEN AGAIN FROM MIDDAY MONDAY ONWARD WITH HELP FROM DIURNAL HEATING. EXPECT HIGHS BOTH SUNDAY AND MONDAY IN THE 80S WITH LOWS BOTH NIGHTS IN THE 65 TO 70 DEGREE RANGE. TUESDAY AND WEDNESDAY... WITH FAST MOVING UPPER LEVEL PATTERN IN PLACE...WILL SEE CHANGEABLE CONDITIONS DURING THIS TIMEFRAME. AT THIS POINT...HAVE CONTINUED LOW CHANCE POPS LATE TUE INTO WED AS ANOTHER FRONT SWEEPS ACROSS THE NORTHEAST. HOWEVER...LOWER CONFIDENCE DUE TO TIMING OF SURFACE FEATURES. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM /TODAY THROUGH FRIDAY NIGHT/...HIGH CONFIDENCE. BEFORE 00Z...VFR THROUGH THE PERIOD. NORTHWEST WINDS WILL BECOME GUSTY NEAR 20 KNOTS...DIMINISHING TOWARDS EVENING. TONIGHT...VFR. PATCHY FOG POSSIBLE ACROSS THE CT RIVER VALLEY REGION. FRIDAY INTO FRIDAY NIGHT...VFR. LIGHT WINDS ON FRIDAY WILL ALLOW SEA BREEZES TO DEVELOP ALONG THE COAST LATE MORNING AND AFTERNOON. SEA BREEZE WILL DIMINISH BY THE EVENING ALLOWING FOR LIGHT WINDS OVERNIGHT AND PATCHY FOG/STRATUS ACROSS THE INTERIOR. KBOS TERMINAL...HIGH CONFIDENCE IN TAF. NORTHWEST WINDS GUST TO 20 KNOTS MIDDAY AND AFTERNOON. LOW CONFIDENCE ON SEA BREEZE DEVELOPMENT. KBDL TERMINAL...HIGH CONFIDENCE IN TAF. OUTLOOK...SATURDAY THROUGH MONDAY... SATURDAY THROUGH SATURDAY NIGHT...MODERATE CONFIDENCE. MAINLY VFR. LIGHT E-SE WINDS FRI NIGHT BECOME S SAT. MVFR-IFR CIGS/VSBYS POSSIBLE IN NORMALLY PRONE VALLEY LOCATIONS BOTH NIGHTS IN PATCHY FOG...AND ALONG THE COASTS SAT NIGHT. SUNDAY THROUGH MONDAY...LOW CONFIDENCE. STARTING OFF VFR EARLY SUN...THEN A MIX OF LOW END VFR TO MVFR. EXPECT SHOWERS ACROSS THE TERMINALS. BRIEF LOCAL IFR IN ANY TSRA. CONTINUED S/SW WINDS.
-- End Changed Discussion --
&& .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT-TERM /TODAY THROUGH FRIDAY/...HIGH CONFIDENCE. 1030 AM UPDATE... HAVE ADJUSTED WAVE HEIGHTS ACCORDINGLY TO WHAT IS OCCURRING THIS MORNING. SOUTH OF BLOCK ISLAND...THE BUOY HAS REMAINED ABOUT 5 FT WITH A PERIOD OF 13 SEC. APPEARS BOTH THE PERIOD AND SWELL WILL MAX OUT BY THIS AFTERNOON. TODAY AND TONIGHT... SOUTH SWELL FROM HURRICANE CRISTOBAL WILL CONTINUE TO BUILD...REACHING A PEAK OF 6 TO 9 FEET ON THE SOUTHERN EXPOSED WATERS. THE HURRICANE ITSELF WILL PASS 375 MILES SOUTHEAST OF NANTUCKET WITH TROPICAL STORM FORCE WINDS EXTENDING ONLY 205 MILES FROM THE CENTER. SO THE NEW ENGLAND WATERS SHOULD HAVE NO EFFECTS OTHER THAN THE ROUGH SWELL. A SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CONTINUES. FRIDAY... HIGH PRESSURE BUILDS OVER NEW ENGLAND AND THE WATERS. THIS WILL MEAN LIGHT WIND...BECOMING ONSHORE NEAR THE COAST. SEAS WILL DIMINISH THROUGH THE DAY. ROUGH SEAS MAY LINGER ON THE WATERS SOUTH AND EAST OF CAPE COD AND NANTUCKET...AND SO A SMALL CRAFT ADVISORY CONTINUES FOR THOSE OUTER WATERS THROUGH THE DAY. OUTLOOK...FRIDAY NIGHT THROUGH MONDAY... FRIDAY NIGHT THROUGH SATURDAY NIGHT...MODERATE CONFIDENCE. LIGHT NE-E WINDS EARLY FRI NIGHT BECOMING SE BY SAT MORNING...THEN SHIFT TO S AND PICK UP DURING THE DAY SAT. GUSTS UP TO 20 KT POSSIBLE ON OUTER WATERS SAT NIGHT. LEFTOVER SWELL ON OUTER WATERS FROM CRISTOBAL FRI NIGHT...THEN SHOULD SUBSIDE. PATCHY FOG POSSIBLE DURING THE OVERNIGHT HOURS... ESPECIALLY ALONG THE S COAST. SUNDAY THROUGH MONDAY...MODERATE CONFIDENCE. S-SW WINDS GUSTING UP TO 20 KT ON SUNDAY...THEN DROP OFF A BIT MONDAY. SEAS INCREASE AGAIN UP TO AROUND 5 FT ON THE SOUTHERN OUTER WATERS DUE TO LONG S-SW FETCH. PATCHY FOG MAY REMAIN AN ISSUE OVER THE WATERS...ESPECIALLY DURING OVERNIGHT PERIODS. SCT SHOWERS/TSTMS REDUCING VSBYS AS WELL. && .BOX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...NONE. MA...HIGH SURF ADVISORY UNTIL 8 AM EDT FRIDAY FOR MAZ020-022>024. NH...NONE. RI...HIGH SURF ADVISORY UNTIL 8 AM EDT FRIDAY FOR RIZ006>008. MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR ANZ231>234. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT FRIDAY FOR ANZ235-237. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM EDT FRIDAY FOR ANZ254>256.
-- End Changed Discussion --
&& $$ SYNOPSIS...WTB/EVT NEAR TERM...DUNTEN SHORT TERM...WTB LONG TERM...EVT AVIATION...DUNTEN/EVT MARINE...WTB/DUNTEN/EVT

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