Area Forecast Discussion
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450
FXUS61 KBOX 100614
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
114 AM EST WED FEB 10 2016

.SYNOPSIS...

FAST MOVING LOW PRESSURE MAY BRING SCATTERED LOCALLY HEAVY SNOW
SHOWERS TO THE REGION WEDNESDAY WITH THE HIGHEST RISK ACROSS
NORTHERN CONNECTICUT AND NEAR THE SOUTH COAST. SOME SCATTERED SNOW
SHOWERS ARE LIKELY THURSDAY AND FRIDAY. BITTERLY COLD WEATHER IS
EXPECTED THIS WEEKEND. THERE IS POTENTIAL FOR MORE PRECIP EARLY NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...

110 AM UPDATE...

CURRENT TEMPS RANGED FROM THE TEENS TO THE MIDDLE 20S. LITTLE CHANGE
EXPECTED THROUGH DAYBREAK BUT SOME LOCATIONS WILL LIKELY CLIMB A A
FEW DEGREES AS CLOUDS INCREASE.

THE MAIN CONCERN WILL BE TOWARD 12Z AS POTENT SHORTWAVE TROUGH
APPROACHES FROM THE WEST.  ATMOSPHERE BECOMES QUITE UNSTABLE BY 12Z
WITH TOTAL TOTALS REACHING BETWEEN 55 AND 60 ALONG WITH STEEP MID
LEVEL LAPSE RATES BETWEEN 7 AND 8 C/KM.  THERE LOOKS TO BE A MESO-
LOW THAT MOVES SOUTH OF US TODAY.  EARLIER GUIDANCE HINTED AT A
HIGHER RISK OF THIS AFFECTING OUR SOUTHERN ZONES...ESPECIALLY NEAR
THE SOUTH COAST. THE 00Z SUITE OF GUIDANCE APPEARS TO BE BACKING
AWAY FROM THIS WITH THIS MESO-LOW TRACKING FURTHER SOUTH.  STILL
HAVE TO WATCH IT CLOSELY THOUGH BECAUSE IF IT DOES INTERACT WITH THE
INSTABILITY/MOISTURE...ITS ONE OF THOSE SITUATIONS WHERE SOME
LOCATIONS PICKUP A QUICK 2 INCHES OF SNOW IN LESS THAN AN HOUR. AT
THIS POINT...LOOKS TO BE A LOW PROBABILITY GIVEN MODEL TRENDS BUT
STILL CAN/T COMPLETELY THROW IN THE TOWEL ON THIS ONE.

REGARDLESS OF THIS MESO-LOW...STILL EXPECT SCATTERED SNOW SHOWERS
AND LOCALLY HEAVIER SQUALLS TODAY.  FAIRLY IMPRESSIVE MOISTURE WILL
COMBINED WITH SHORTWAVE ENERGY/MOISTURE AND THE INSTABILITY
MENTIONED IN THE PREVIOUS PARAGRAPH.  IN FACT...THERE IS A SECONDARY
SHORTWAVE THAT MAY CLIP OUR NORTHWEST ZONES AS WELL.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
*** SCATTERED BUT LOCALLY HEAVY SNOW SHOWERS POSSIBLE WITH THE
  HIGHEST RISK ACROSS WESTERN MA/CT AND THE SOUTH COAST ***

WEDNESDAY ...

IMPRESSIVE SHORT WAVE TROUGH MOVES OVER OR JUST OF THE AREA
TOMORROW. THIS FEATURE SHOWS UP NICELY AS A PV ANOMALY ON THE
TROPOPAUSE. MODEST SYNOPTIC SCALE LIFT WITH THIS FEATURE ALONG WITH
DEEP LAYER MOISTURE. THUS THE ENTIRE REGION WILL SEE SCATTERED SNOW
SHOWERS. THE DIFFICULT PART OF THE FORECAST IS THE INTENSITY AND
AREAL COVERAGE OF THIS ACTIVITY AS MESOSCALE ATTRIBUTES COME INTO
PLAY.

GOOD MODEL AGREEMENT THAT THE ATMOSPHERE WILL BECOME QUITE UNSTABLE
WITH BOTH LOW AND MID LEVEL LAPSE RATES GREATER THAN MOIST ADIABATIC
/6.5C-KM/ AND POSSIBLY APPROACHING 8C/KM ALONG WITH TT NEARING 60!
FURTHERMORE THERE APPEARS TO BE SUFFICIENT MOISTURE IN THE COLUMN
FOR THIS INSTABILITY TO BE REALIZED...POTENTIALLY OFFERING A STRONG
RESPONSE IN THE FORM OF SCATTERED HEAVY SNOW SHOWERS.

UNFORTUNATELY MODEL GUID IS NOT IN GOOD AGREEMENT ON SIMULATING
THESE HEAVIER SNOW SHOWERS. THE 12Z GFS IS MOST ROBUST BUT MAY BE
SUFFERING FROM SOME CONVECTIVE FEEDBACK. HOWEVER THE MODEL CONSENSUS
IS THAT THE MOST INTENSE SNOW SHOWERS MAY DEVELOP ACROSS LONG ISLAND
NY AND THEN MOVE ENE OVER BID-MVY AND POSSIBLY ONTO THE SOUTH COAST
OF MA AND RI. THUS GREATEST RISK IS ACROSS THIS REGION ALONG WITH A
POSSIBLE BURST IN THE MORNING OVER WESTERN CT-MA.

WHILE POTENTIAL SNOW TOTALS ARE NOT THAT IMPRESSIVE THE IMPACT WOULD
RESULT FROM A QUICK 1-2" IN A SHORT PERIOD OF TIME. IF THE GFS
SIMULATION IS CORRECT LOCALIZED AMOUNTS OF UP TO 3-4" ARE POSSIBLE.

TIMELINE...SNOW SHOWERS APPROACH WESTERN CT-MA INCLUDING
HARTFORD/SPRINGFIELD AROUND 12Z...THUS POTENTIALLY IMPACTING THE
MORNING COMMUTE. SNOW SHOWERS OVERSPREAD THE REMAINDER OF THE REGION
15Z-18Z AND POSSIBLY LINGERING ACROSS RI/EASTERN MA INCLUDING BOSTON-
PROVIDENCE CORRIDOR TIL 21Z. HENCE POSSIBLY IMPACTING THE LATE DAY
COMMUTE HERE. WILL ISSUE A SPECIAL WEATHER STATEMENT TO HEIGHTEN
PUBLIC AWARENESS ON POTENTIAL IMPACTS AND ALSO ADDRESS THE
UNCERTAINTY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...

* SNOW SHOWERS POSSIBLE THROUGH SAT
* MUCH COLDER AIR MOVES INTO SOUTHERN NEW ENGLAND FOR THE WEEKEND
* MORE PRECIPITATION POSSIBLE EARLY NEXT WEEK

A COMPLEX FORECAST FOR THE LONG TERM.  THE MODELS ARE IN FAIRLY GOOD
AGREEMENT WITH THE SYNOPTIC SCALE PATTERN WITH CONTINUED TROUGHING
OVER THE EAST COAST AND RIDGING OVER THE WESTERN CONUS.  DIFFERENCES
AND CHALLENGES COME IN THE EXACT PATH OF THE SYNOPTIC FEATURES...
INCLUDING SHORTWAVES...AS WELL AS THE MORE MESOSCALE FEATURES.

WEDNESDAY NIGHT...HIGH CONFIDENCE.
A WEAK SHORTWAVE WILL EXIT SOUTHERN NEW ENGLAND...PUSHING LOW
PRESSURE OUT OF NORTHERN NEW ENGLAND AND INTO THE GULF OF MAINE.
THIS WILL PULL A WEAK COLD FRONT THROUGH THE REGION.  EXPECT THE
OVERNIGHT PERIOD TO BE MOSTLY DRY WITH THE MAIN IMPACT FROM THE
FRONT BEING SOME CLOUDS AND COLDER TEMPERATURES MOVING IN FOR
THURSDAY.

THURSDAY...MODERATE CONFIDENCE.
A STRONGER SHORTWAVE TROUGH MOVES THROUGH SOUTHERN NEW ENGLAND
THURSDAY. BELOW NORMAL TEMPERATURES ARE EXPECTED BEHIND THE COLD
FRONT THAT MOVED THROUGH WEDNESDAY NIGHT.  HOWEVER...THERE IS ENOUGH
LIFT AND MOISTURE ASSOCIATED WITH THE SHORTWAVE THAT WE COULD SEE
SOME SCATTERED SNOW SHOWERS ACROSS THE REGION.  NOT MUCH EXPECTED AT
THIS TIME...PERHAPS AS MUCH AS AN INCH OR TWO IN A FEW SPOTS.

FRIDAY...HIGH CONFIDENCE.
AS AN UPPER LEVEL TROUGH MOVES INTO THE NORTHEASTERN U.S...LOW
PRESSURE IN THE GREAT LAKES MOVES THROUGH NORTHERN NEW ENGLAND
BRINGING AN ARCTIC FRONT THROUGH SOUTHERN NEW ENGLAND. AGAIN...THIS
WILL BRING A CHANCE OF SNOW SHOWERS AHEAD OF THE FRONT. JUST LIGHT
AMOUNTS EXPECTED AT THIS TIME...A DUSTING TO MAYBE AN INCH OR TWO.
THE BIG STORY WITH THIS FRONT WILL BE THE STRONG PUSH OF ARCTIC AIR
MOVING INTO THE REGION. TEMPERATURES FRIDAY WILL ALREADY BE MORE
THAN 10 DEGREES BELOW NORMAL FOR MID FEBRUARY AND THE COLDER AIR IS
YET TO COME.

THIS WEEKEND...HIGH CONFIDENCE.
NOT MUCH...IF ANY...PRECIPITATION IS EXPECTED. INSTEAD THE COLD WILL
TAKE CENTER STAGE...ALONG WITH SOME BITTERLY COLD WIND CHILLS.
ARCTIC AIR CONTINUES TO SEEP INTO SOUTHERN NEW ENGLAND WITH HIGHS
EXPECTED TO BE 20 TO EVEN 25 DEGREES BELOW NORMAL.  WHILE THIS IS
STILL SEVERAL DAYS OUT AND THERE IS SOME UNCERTAINTY TO BE
HAD...09/12Z EPS PROBABILITIES HAVE AN OVER 90 PERCENT CHANCE OF LOW
TEMPERATURES DROPPING BELOW ZERO AND OVER 80 PERCENT CHANCE OF LOW
TEMPERATURES BELOW NEGATIVE 10 DEGREES!  THUS...HAVE HIGH CONFIDENCE
IN BITTER COLD TEMPERATURES THROUGH THE WEEKEND.

IN ADDITION...ON SATURDAY...STRONG LOW PRESSURE IN THE MARITIMES
COUPLED WITH AN EQUALLY STRONG HIGH PRESSURE IN THE GREAT LAKES/OHIO
VALLEY REGION WILL RESULT IN A VERY TIGHT PRESSURE GRADIENT ACROSS
SOUTHERN NEW ENGLAND.  THIS WILL RESULT IN NORTHWESTERLY WINDS
AROUND 20 MPH...GUSTING TO AROUND 30 MPH...EVEN THROUGHOUT MUCH OF
SATURDAY NIGHT.  WITH TEMPERATURES AS COLD AS THEY ARE CURRENTLY
FORECAST TO BE...EVEN JUST SLIGHTLY BREEZY CONDITIONS WILL RESULT IN
VERY COLD WIND CHILLS.  AT THIS TIME...WE ARE LOOKING AT WIND CHILLS
BETWEEN 20 AND 30 DEGREES BELOW ZERO SATURDAY NIGHT.  DURING THE DAY
SATURDAY...WIND CHILLS IN THE SINGLE DIGITS BELOW ZERO AND 5 TO 15
DEGREES BELOW ZERO FOR SUNDAY.  IT WILL DEFINITELY BE A WEEKEND TO
BUNDLE UP AND STAY INDOORS.

MONDAY AND TUESDAY...LOW CONFIDENCE.
THERE ARE SOME INDICATIONS THAT THERE MAY BE A STORM BRINGING SOME
PRECIPITATION TO SOUTHERN NEW ENGLAND EARLY NEXT WEEK.
HOWEVER...WHETHER IT IS RAIN OR SNOW IS UNCERTAIN...AS WELL AS THE
TRACK OF THE POTENTIAL STORM.  STAY TUNED TO FUTURE FORECASTS FOR
MORE INFORMATION.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /TODAY THROUGH THURSDAY/...

TODAY...MODERATE CONFIDENCE.  A MIXTURE OF VFR TO MVFR CIGS EARLY
THIS MORNING SHOULD BECOME MAINLY MVFR AFTER 12Z AND CONTINUE
THROUGH THE AFTERNOON.  OTHERWISE...WE WILL BE WATCHING AN AREA OF
SCATTERED SNOW SHOWERS WHICH MAY WORK INTO WESTERN MA/NORTHERN CT
BETWEEN 9Z AND 12Z.  THIS SCATTERED ACTIVITY SHOULD SPREAD ACROSS
THE REST OF THE REGION THROUGH EARLY AFTERNOON.  WHILE MUCH OF THE
ACTIVITY WILL BE LIGHT...A FEW HEAVIER BURSTS OF SNOW SHOWERS/SQUALLS
ARE EXPECTED...WHICH MAY RESULT IN BRIEF IFR TO LIFR CONDITIONS.
BULK OF THE ACTIVITY SHOULD EXIT THE COAST BETWEEN 21Z AND 00Z.

TONIGHT...MODERATE TO HIGH CONFIDENCE.  MAINLY VFR CONDITIONS...BUT
WILL HAVE TO WATCH FOR SOME SCATTERED SNOW SHOWERS DEVELOPING ACROSS
SOUTHWEST MA/NORTHERN CT TOWARDS 12Z THURSDAY.

THURSDAY...MODERATE TO HIGH CONFIDENCE.  MAINLY VFR CONDITIONS BUT
SCATTERED FLURRIES/SNOW SHOWERS MAY RESULT IN BRIEFLY LOWER
CONDITIONS.  NORTHWEST WINDS WILL LIKELY GUST TO AROUND 30 KNOTS BY
MID TO LATE AFTERNOON BEHIND A STRONG COLD FRONT.

KBOS TERMINAL...MODERATE CONFIDENCE IN TAF TODAY.  BIGGEST
UNCERTAINTY IS THE TIMING OF ANY SCATTERED SNOW SHOWERS WHICH MAY
RESULT IN BRIEF POOR VISIBILITY.

KBDL TERMINAL...MODERATE CONFIDENCE IN TAF TODAY. BIGGEST UNCERTAINTY
IS THE TIMING OF ANY SCATTERED SNOW SHOWERS WHICH MAY RESULT IN BRIEF
POOR VISIBILITY.

OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...

FRIDAY...MODERATE CONFIDENCE.  MAINLY VFR CONDITIONS. ARCTIC FRONT
MOVES THROUGH THE REGION FRIDAY WITH GUSTY NW WINDS. CHANCE OF -
SHSN. EXPECTED ACCUMULATION LESS THAN TWO INCHES.

SATURDAY AND SUNDAY...MODERATE CONFIDENCE. MAINLY VFR CONDITIONS.
NW WINDS GUSTING TO 25-30 KTS LIKELY. BITTERLY COLD TEMPERATURES
EXPECTED.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.

SHORT TERM /THROUGH THURSDAY/...HIGH CONFIDENCE.

TONIGHT ...

LIGHT WINDS BUT LARGE EASTERLY SWELLS CONTINUE ON THE OCEAN WATERS
OF MA AND RI. OTHER THAN AN ISOLATED SNOW SHOWER MAINLY DRY AND GOOD
VSBY.

WED ...

LOW PRES FORMS OVER SOUTHERN NEW ENGLAND TOMORROW. SCATTERED SNOW
SHOWERS WILL ACCOMPANY THIS BROAD AREA OF LOW PRES. VSBY MAY LOWER
BELOW 1 MILE IN A FEW OF THE HEAVIER SNOW SHOWERS.

OUTLOOK /THURSDAY NIGHT THROUGH SUNDAY/...

FRIDAY...MODERATE CONFIDENCE.  WINDS AND SEAS SUBSIDE AS HIGH
PRESSURE TRIES TO BUILD IN AHEAD OF AN ARCTIC FRONT THAT MOVES
THROUGH FRIDAY NIGHT. SMALL CRAFT ADVISORIES LIKELY.

SATURDAY...MODERATE CONFIDENCE.  NORTHWESTERLY WINDS CONTINUE
BETWEEN LOW PRESSURE IN THE MARITIMES AND HIGH PRESSURE IN THE GREAT
LAKES.  SMALL CRAFT ADVISORIES DEFINITE...WITH A LOW PROBABILITY OF
GALE FORCE WINDS.

SUNDAY...MODERATE CONFIDENCE.  WINDS AND SEAS DIMINISH AS HIGH
PRESSURE BUILDS OVER THE WATERS.  SMALL CRAFT ADVISORIES MAY STILL
BE POSSIBLE.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ235-
     237-250-254>256.
     SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR ANZ251.

&&

$$
SYNOPSIS...NOCERA/RLG
NEAR TERM...FRANK
SHORT TERM...NOCERA
LONG TERM...RLG
AVIATION...FRANK/RLG
MARINE...NOCERA/RLG



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