484
FXUS61 KBOX 171518
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
1018 AM EST MON FEB 17 2025
SYNOPSIS
VERY STRONG WINDS CONTINUE TODAY INTO TUESDAY, THOUGH THEY WON'T BE
AS STRONG ON TUESDAY. COLDER THAN NORMAL TEMPERATURES EXPECTED EARLY
IN THE WEEK WITH HIGHS IN THE 20S. WINDS DECREASE INTO WEDNESDAY
WITH SLIGHTLY WARMER TEMPERATURES IN THE UPPER 20S. STILL
MONITORING A POTENTIAL COASTAL STORM THAT MAY BRING US ANOTHER
CHANCE OF SNOW LATER IN THE WEEK.
NEAR TERM /UNTIL 6 PM THIS EVENING/
10AM UPDATE
ALREADY SEEING PEAK WIND GUSTS OF 68MPH IN WORCESTER AND
FITCHBURG THIS MORNING, WITH PEAK WIND GUSTS OF 56MPH IN BOSTON
AND 52MPH IN PROVIDENCE. WITH MORE SUN THEN CLOUDS, DIURNAL
MIXING WILL CONTINUE TO ENHANCE THE MIXING POTENTIAL IN THE
BOUNDARY LAYER, ALLOWING THE 4-5KFT WINDS OF 60-70MPH TO MIX
DOWN TO THE SURFACE THIS AFTERNOON.
KEY MESSAGES...
* STRONG, POTENTIALLY DAMAGING WINDS TODAY.
* BELOW NORMAL TEMPERATURES WITH HIGHS IN THE 20S.
THE CENTER OF THE LOW WHICH BROUGHT ALL OUR PRECIPITATION YESTERDAY
HAS MOVED OVER NOVA SCOTIA THIS MORNING PLACING SNE BENEATH DRY AND
COLD WNW FLOW THROUGH THE COLUMN. THIS COLD ADVECTION WILL LEAD TO
RAPIDLY DROPPING TEMPERATURES AS LOWS DIP INTO THE SINGLE DIGITS AND
MID TEENS EARLY THIS MORNING. AT THE MID LEVELS 850 MB TEMPS DROP
FROM +8C ON SUNDAY TO -16C TODAY LEADING TO HIGH TEMPERATURES AS
MUCH AS 20 DEGREES COLDER, IN THE 20S. COMBINED WITH THE WIND IT
WILL FEEL LIKE THE SINGLE DIGITS AND TEENS. THIS WIND IS DUE TO THE
TIGHT PRESSURE GRADIENT BETWEEN THE EXITING LOW AND HIGH PRESSURE
EXTENDING INTO THE MIDWEST WHICH RESULTS IN A 50-60 KT LLJ AT 850
MB. GIVEN DEEP CAA WE SHOULD SEE A DEEPLY MIXED BOUNDARY LAYER;
BUFKIT SOUNDINGS INDICATE MIXING AS HIGH AS 800 MB. THE RESULT WILL
BE POTENTIALLY DAMAGING WIND GUSTS AS HIGH AS 55 TO 65 MPH; WHETHER
OR NOT WE'LL ACHIEVE THOSE STRONGEST GUSTS MAY DEPEND ON HOW MUCH
DIURNAL WARMING WE CAN ACHIEVE. WE SHOULD SEE A MIX OF CLOUDS AND
SUN WITH MOISTURE AT 850 MB AND W WINDS LEADING TO OROGRAPHICALLY
FORCED CLOUDCOVER OVER THE BERKSHIRES AND WORCESTER HILLS.
SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/
KEY MESSAGES...
* REMAINING GUSTY OVERNIGHT AND TUESDAY.
* BELOW NORMAL TEMPERATURES.
THE LLJ PERSISTS OVERNIGHT BUT LOSS OF DIURNAL HEATING SHOULD
DECREASE THE MIXING HEIGHT AND KEEP THOSE GUSTS IN THE 40 TO 50 MPH
RANGE. WIND CHILL VALUES DIP INTO THE LOW AND EVEN NEGATIVE SINGLE
DIGITS! TUESDAY, MORE OF THE SAME WITH GUSTY AND COLD CONDITIONS.
CLIMATOLOGICALLY HIGHS ARE TYPICALLY IN THE UPPER 30S AND LOW 40S,
BUT WITH 850 MB TEMPS EVEN COLDER THAN MONDAY, NEAR -19C, HIGH
TEMPERATURES WILL BE MUCH BELOW NORMAL, IN THE LOW 20S FOR MOST
LOCATIONS. IN THE HIGH ELEVATIONS TEMPS WON'T GET OUT OF THE TEENS
ALL DAY. DRY WEATHER PREVAILS UNDER BUILDING HIGH PRESSURE.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/
KEY MESSAGES:
* WINDS WEAKEN OVERNIGHT TUESDAY INTO WEDNESDAY.
* MONITORING POTENTIAL FOR A COASTAL STORM THURSDAY INTO FRIDAY.
DETAILS:
TUESDAY NIGHT - WEDNESDAY:
THE PRESSURE GRADIENT CONTINUES TO RELAX TUESDAY NIGHT INTO
WEDNESDAY TRENDING WINDS DOWNWARD. IT WILL BE ANOTHER CHILLY NIGHT
TUESDAY NIGHT WITH LOWS DROPPING INTO THE SINGLE DIGITS AND TEENS.
WIND CHILLS TOP INTO THE SINGLE DIGITS TO NEGATIVE SINGLE
DIGITS. ON WEDNESDAY, THE AIRMASS WILL BEGINS TO MODERATE AS A
WEAK RIDGE BUILDS IN, "WARMING" HIGHS BACK INTO THE MID TO UPPER
20S.
THURSDAY AND FRIDAY:
ENSEMBLE GUIDANCE CONTINUES TO DISPLAY A POTENTIAL COASTAL LOW
FORMING IN THE MID-ATLANTIC THEN TRACKING NORTHEASTWARD TOWARD NEW
ENGLAND GENERALLY IN THE THURSDAY INTO EARLY FRIDAY TIMEFRAME. TRACK
STILL CONTINUES TO VARY AMONG ENSEMBLE AND DETERMINISTIC SOLUTIONS
WITH RUN TO RUN DIFFERENCES AS WELL. OVER THE LAST BUNCH OF RUNS
HOWEVER, THERE IS HAS BEEN A GENERAL TREND FOR THE LOW TRACKING
FURTHER SOUTH OVER THE MID-ATLANTIC THEN PROGRESSING MORE ENE. THIS
TRACK HAS SUPPORTED THE MAIN ENVELOPE OF SOLUTIONS RIGHT NOW AS MORE
OF A "GRAZE" ACROSS THE EASTERN PORTION OF SOUTHERN NEW ENGLAND.
WITH A COLD PATTERN IN PLACE, THIS WOULD MEAN SNOW IF THE TRACK
FAVORED PRECIPITATION OVER SOUTHERN NEW ENGLAND. GIVEN CURRENT
ENSEMBLE MEANS THIS WOULD MEAN THE HIGHEST CHANCES FOR SNOWFALL
WOULD FURTHER EAST SUCH AS THE CAPE AND ISLANDS. GIVEN UNCERTAINTY
IN THE TRACK, AMOUNTS AND THE PRECIPITATION PROBABILITIES ACROSS
SOUTHERN NEW ENGLAND REMAIN LOWER CONFIDENCE. THEY SHOULD BECOME
MORE CLEAR IF MODELS STAY CONSISTENT WITH THE STORM TRACKING FURTHER
EAST.
WEEKEND:
WEAK UPPER LEVEL RIDGING MOVES INTO SOUTHERN NEW ENGLAND FOR THE
WEEKEND. HIGHS STAY BELOW NORMAL IN THE LOW TO MID 30S.
AVIATION /15Z MONDAY THROUGH FRIDAY/
FORECAST CONFIDENCE LEVELS:
LOW - LESS THAN 30 PERCENT.
MODERATE - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
12Z TAF UPDATE...HIGH CONFIDENCE
TODAY:
VFR AND VERY WINDY. WINDS GUSTING 40-50 KNOTS, POSSIBLY UP TO
60 KNOTS IN THE ELEVATED TERRAIN. SCT TO BKN CLOUD DECKS SPILL
OFF THE TERRAIN ACROSS WESTERN MA EXTENDING EASTWARD AT
4000-6000 FT.
TONIGHT AND TUESDAY:
VFR. WINDS REMAIN STRONG OUT OF THE WEST AT 35-45 KNOTS. WINDY
CONDITIONS CONTINUE TUESDAY WITH SLIGHTLY WEAKER WEST GUSTS
30-40 KTS.
KBOS TAF...HIGH CONFIDENCE
KBDL TAF...HIGH CONFIDENCE
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...
TUESDAY NIGHT: VFR. WINDY WITH GUSTS UP TO 35 KT.
WEDNESDAY: VFR. BREEZY.
WEDNESDAY NIGHT: VFR.
THURSDAY: MAINLY VFR, WITH LOCAL MVFR POSSIBLE. BREEZY. CHANCE
SN.
THURSDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.
CHANCE SN.
FRIDAY: VFR. BREEZY.
MARINE
FORECASTER CONFIDENCE LEVELS:
LOW - LESS THAN 30 PERCENT.
MEDIUM - 30 TO 60 PERCENT.
HIGH - GREATER THAN 60 PERCENT.
MODERATE CONFIDENCE.
DANGEROUS MARINE CONDITIONS TODAY AS A STRONG COLD FRONT BRINGS
STRONG WESTERLY SUSTAINED WINDS BETWEEN 35-45 KNOTS AND GUSTS
AS HIGH AS 55-60 KNOTS. THESE STRONG WINDS WILL CAUSE VERY ROUGH
SEAS, RISING TO 10-15 FEET IN THE OPEN WATERS, AND 4-8 FEET IN
CAPE COD BAY, MVY SOUNDS, AND NANTUCKET SOUND. THE COLD FRONT
WILL BRING SUBFREEZING TEMPERATURES WELL OUT INTO THE OPEN
WATERS BY MONDAY NIGHT. CONFIDENCE IS HIGH THAT MODERATE
FREEZING SPRAY WILL OCCUR MONDAY NIGHT INTO WEDNESDAY MORNING,
WITH A LOW CHANCE AT HEAVY FREEZING SPRAY. A HEAVY FREEZING
SPRAY ADVISORY HAS BEEN ISSUED FOR MONDAY NIGHT THROUGH
WEDNESDAY MORNING.
OUTLOOK /TUESDAY NIGHT THROUGH FRIDAY/...
TUESDAY NIGHT: STRONG WINDS WITH GUSTS UP TO 35 KT. ROUGH SEAS
UP TO 11 FT. FREEZING SPRAY.
WEDNESDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS
UP TO 25 KT. LOCAL ROUGH SEAS. CHANCE OF FREEZING SPRAY.
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT.
THURSDAY: WINDS LESS THAN 25 KT. SEAS LOCALLY APPROACHING 5 FT.
CHANCE OF SNOW. LOCAL VISIBILITY 1 NM OR LESS.
THURSDAY NIGHT: MODERATE RISK FOR SMALL CRAFT ADVISORY WINDS
WITH GUSTS UP TO 25 KT. AREAS OF ROUGH SEAS. CHANCE OF SNOW,
CHANCE OF FREEZING SPRAY. LOCAL VISIBILITY 1 NM OR LESS.
FRIDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS UP
TO 25 KT. AREAS OF ROUGH SEAS. CHANCE OF FREEZING SPRAY, SLIGHT
CHANCE OF SNOW.
BOX WATCHES/WARNINGS/ADVISORIES
CT...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR CTZ002>004.
MA...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR MAZ017>024.
HIGH WIND WARNING UNTIL 7 PM EST THIS EVENING FOR MAZ002>004-
008>012-026.
HIGH WIND WARNING UNTIL 1 AM EST TUESDAY FOR MAZ005>007-
013>016.
RI...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR RIZ001>008.
MARINE...STORM WARNING UNTIL 4 AM EST TUESDAY FOR ANZ230-231-250-251-
254>256.
FREEZING SPRAY ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST
WEDNESDAY FOR ANZ230>237-250-251-254>256.
GALE WARNING UNTIL 7 PM EST TUESDAY FOR ANZ232>235-237.
GALE WARNING UNTIL 4 AM EST TUESDAY FOR ANZ236.
SYNOPSIS...BW/MENSCH
NEAR TERM...BW/KP
SHORT TERM...BW
LONG TERM...MENSCH
AVIATION...BW/MENSCH
MARINE...BW/MENSCH
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