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000
FXUS61 KBOX 031355
AFDBOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
955 AM EDT WED JUN 3 2015

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER NEW ENGLAND TODAY BRINGING DRY AND
SOMEWHAT MILDER WEATHER TODAY AND THURSDAY. A SPOT SHOWER IS
POSSIBLE FRIDAY INTO EARLY SATURDAY WITH DRY WEATHER FOR SUNDAY.
THE CHANCE FOR MORE RAINFALL RETURNS MONDAY. TEMPERATURES REMAIN
BELOW SEASONABLE UNTIL THE LATE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...

10 AM UPDATE...

EARLY MORNING FOG HAS BURNED OFF AND GIVEN WAY TO MOSTLY SUNNY
CONDITIONS OVER CT...RI AND INTO WESTERN-CENTRAL MA. FARTHER EAST
INTO EASTERN MA LOTS OF STRATO-CU HAS DEVELOPED. THIS IS IN
RESPONSE TO LOW LEVEL MOISTURE TRAPPED BENEATH SUBSIDENCE
INVERSION. LATEST MODEL GUIDANCE INCLUDING 06Z NAM AND GFS SUGGEST
THIS LOW LEVEL MOISTURE WILL ADVECT WESTWARD INTO RI AND CENTRAL
MA. HOWEVER THE STRONG/HIGH JUNE SUN ANGLE WILL ERODE THESE CLOUDS
FROM THE EDGES INWARD. HOWEVER THE COOL ONSHORE IN EASTERN MA WILL
OFFSET THE CLOUD EROSION A BIT. SO TREND WILL LIKELY BE FOR
STRATO-CU TO BLOSSOM IN AREAL COVERAGE A BIT HERE MID TO LATE
MORNING AND THEN SLOWLY ERODING AS THE AFTERNOON PROGRESSES. SO IN
A NUTSHELL MORE SUN AND WARMEST TEMPS ACROSS CT RVR VALLEY
INCLUDING I-91 CORRIDOR WITH CLOUDS MOST NUMEROUS OVER RI AND
EASTERN MA...BUT ERODING SLOWLY AS THE AFTERNOON PROGRESSES.

PREVIOUS FORECAST CAPTURES THESE DETAILS NICELY SO NO MAJOR
CHANGES WITH THIS UPDATE. EARLIER DISCUSSION BELOW.

================================================================

NORTHERN STREAM SHORTWAVE IS MOVING OFF THROUGH THE MARITIMES WITH
A RESULTING NORTHWEST FLOW ACROSS NEW ENGLAND. SATELLITE IMAGERY
SHOWS LINGERING LOW CLOUDS OVER SOUTHERN NEW ENGLAND WHILE
CLEARING MOVES ACROSS NEW YORK INTO VERMONT. THE TREND OF THIS
CLEARING WOULD BRING IT ACROSS SOUTHERN NEW ENGLAND BY EARLY
AFTERNOON.

SATELLITE IMAGES ALSO SHOW LOW CLOUDS MOVING NORTH
INTO CENTRAL PA. THE UPPER FLOW IS SPLIT. THE NORTHERN STREAM
SWEEPS ACROSS ONTARIO-NEW YORK-NEW ENGLAND WHILE THE SOUTHERN
STREAM PUSHES NORTH OVER THE MID ATLANTIC STATES. THE CONFLUENT
ZONE FOR THESE TWO FLOWS IS ACROSS CENTRAL PA-NJ AND ALONG OR JUST
SOUTH OF LONG ISLAND. THERE IS REASONABLE CONCERN THAT THE
SOUTHERN CLOUDS COULD MOVE FARTHER NORTH THAN DEPICTED AND KEEP
CLOUDS ALONG THE NEW ENGLAND SOUTH COAST. BUT THE MOST LIKELY
SCENARIO KEEPS THESE CLOUDS TO OUR SOUTH.

WITH INCREASING SUNSHINE BY AFTERNOON...MIXING SHOULD REACH TO AT
LEAST 900 MB AND POSSIBLY 850 MB. TEMPERATURES AT THE TOP OF THESE
LAYERS WOULD SUPPORT MAX TEMPS AROUND 70 OR THE LOWER 70S. HIGH
PRESSURE OVER CANADA WILL BRING AN EAST FLOW INTO THE REGION.
ALONG THE EAST MASS COAST THIS WILL BRING CHILLED MARINE AIR
ONSHORE...SO MAX TEMPS THERE MAY STRUGGLE TO REACH 60.

&&

.SHORT TERM /THURSDAY/...
HIGH PRESSURE BRINGS MOSTLY CLEAR SKIES AND LIGHT WIND. THE BEST
CHANCE OF THIS WILL BE IN AREAS NORTH OF THE MASS PIKE. WITH DEW
POINTS IN THE 40S...EXPECT MIN TEMPS IN THE SAME RANGE. SOUTH
COASTAL AREAS...WITH A FEW MORE CLOUDS...MAY STAY AROUND 50.

THURSDAY...
SOUTHERN STREAM SHORTWAVE GENERATES A COASTAL LOW. THE ENTIRE
SYSTEM WILL TRY TO SPREAD CLOUDS UP THE COAST INTO NEW ENGLAND.
THE BEST CHANCE OF CLOUDS WILL BE ALONG THE SOUTH COAST...BUT EVEN
THE INTERIOR SHOULD SEE SOME INCREASE IN SKY COVER. THE OVERALL
WEATHER HERE WILL BE DRY WITH A CONTINUING EAST FLOW. THIS AGAIN
WILL SUPPORT WARMEST TEMPS IN THE CT VALLEY AND COOLEST TEMPS
ALONG THE MASS EAST COAST. EXPECT A RANGE OF 60-65 ALONG THE
COAST AND 70-75 INTERIOR WEST.

&&

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

* A A SPOT SHOWER FRI-SAT
* DRY AND SEASONABLE SUN THEN THREAT OF SHOWERS RETURNS MON AND TUE

OVERVIEW AND MODEL PREFERENCES...
CONTINUATION OF MODEL STRUGGLES WITH THE 03.00Z RUNS. THE LIKELY
ISSUE IS THE RATHER AMPLIFIED SRN STREAM...WHICH FEATURES A
CENTRAL CONUS BLOCK WITH OMEGA CHARACTERISTICS. SO THEN THE
QUESTION BECOMES...DO A COUPLE OF NRN STREAM WAVES PHASE WITH THE
TROF ACROSS THE MID ATLANTIC /THE E SIDE OF THE BLOCK/ AND TO WHAT
EXTENT. THE FIRST SHOT IS FRI INTO SAT. EXACTLY HOW DEEP WILL
ULTIMATELY DEFINE WHETHER THE INFLUENCE OF A WEAK BAROCLINIC WAVE
NEAR THE SFC...DEEPENING OFF THE MID ATLANTIC WILL INTERACT WITH
AN INCREASED MOISTURE STREAM. MODELS ARE BACK AND FORTH ON
THIS...BUT THE ECENS MEAN CONTINUES TO SHOW RELATIVELY GOOD
CONSISTENCY. A COLD FRONTAL PASSAGE ALIGNED WITH THE STRONGEST
VORTEX OF THE WAVE MOVES THROUGH EARLY SAT. WHILE THIS MAY ALSO
INCREASES CHANCES FOR PRECIP...AT ODDS IS A REMNANT SUBSIDENCE
INVERSION WHICH BUFKIT CONTINUES TO SUGGEST FOR BOTH DAYS.
FOLLOWING THIS FEATURE...THE NRN STREAM BECOMES DOMINANT AS THE
BLOCK BREAKS DOWN AND EJECTS WEAK RIDGING INTO THE NRN
STREAM...YIELDING HIGH PRES FOR EARLY NEXT WEEK. BUT...ONCE AGAIN
STREAM PHASING WITH A MORE ROBUST /AND COLDER/ NRN STREAM WAVE
WILL MAKE A DIFFERENCE IN HOW ACTIVE THE PATTERN IS THROUGH THE
MID POINT OF NEXT WEEK. INCREASING POPS...BUT EXACT DETAILS WILL
NEED TO BE IRONED OUT.

DETAILS...

THU NIGHT INTO FRI...
INCREASING MOISTURE THROUGH THE COLUMN WITH PWATS APPROACHING
1.50 INCHES BY FRI /ABOUT 1 STD DEVIATION ABOVE NORMAL/. EXPECTING
INCREASING CLOUDS WITH THIS MOISTURE BUT ANY PRECIP WILL BE
ASSOCIATED WITH WEAK BAROCLINIC WAVE DEVELOPING WELL TO THE S.
ECMWF OPERATIONAL CURRENTLY THE MOST ROBUST WITH QPF. WITH THE
ECENS KEEPING MORE OF THE PRECIP OFFSHORE. THEREFORE...WILL
MAINTAIN SOME POPS BUT LIKELY LOWER THEM SOMEWHAT FROM PREVIOUS
FORECAST. SHOWERY IN NATURE...SO IT/S POSSIBLE SOME LOCATIONS
REMAIN DRY ESPECIALLY TOWARD THE NRN HALF OF THE REGION. TEMPS
REMAIN NEAR TO BELOW NORMAL.

FRI NIGHT INTO SAT...
AS THE UPPER LVL TROF MOVES ACROSS THE AREA...A COLD FRONT WILL
APPROACH FROM THE W. SUBSIDENCE INVERSION AND INVERTED RIDGE
REMAIN IN PLACE...SO ANY PRECIP WILL LIKELY BE FROM LEFTOVER
CONVECTION UPSTREAM...OR DEVELOP WEAKLY IN SITU. ONCE
AGAIN...GOING WITH THE LOWER END OF POPS HERE AS IT/S LIKELY SOME
AREAS ONCE AGAIN REMAIN DRY.

SAT NIGHT THROUGH EARLY MON...
THE REMNANTS OF A CENTRAL CONUS BLOCK WILL MOVE E OF THE REGION
WITH 1020+ HPA SFC HIGH PRES IN TOW. EXPECT A PERIOD OF MAINLY DRY
WX. TEMPS AT OR NEAR SEASONAL NORMALS.

LATE MON INTO MID WEEK...
ONCE AGAIN...UNCERTAINTY ABOUNDS HERE DUE TO DIFFERENCES IN THE
FINAL STRENGTH OF A DEEPENING WAVE ALOFT. SOME ACTUALLY SHOW THIS
WAVE CUTTING OFF COMPLETELY /A VERY SLOW SOLUTION FROM THE ECMWF/
WHILE OTHERS ARE SLOW...BUT A BIT MORE PROGRESSIVE. IN ANY
CASE...NOTING INCREASED RISK FOR PERIODIC -SHRA AND POSSIBLY EVEN
T-STORMS THROUGH THIS PERIOD. THE DEEPER WAVE IS ALSO ABLE TO
HARNESS MORE SUBTROPICAL MOISTURE THAN IS AVAILABLE FOR THE END OF
THIS WEEK. PWATS MAY APPROACH 2+ STD DEVIATIONS ABOVE NORMAL FOR
THIS PERIOD.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
FORECASTER CONFIDENCE LEVELS...

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

10 AM UPDATE...

NOT MUCH CHANGE FROM 12Z TAFS. MVFR WILL BE MOST NUMEROUS ACROSS
RI AND EASTERN MA TERMINALS...BUT TRENDING TOWARD VFR MID TO LATE
AFTERNOON. VFR ELSEWHERE. LIGHT NORTH WINDS INLAND BECOME LGT/VRBL
THIS AFTERNOON. NEAR THE COAST...LIGHT ONSHORE WINDS.

==================================================================

TODAY...MODERATE CONFIDENCE.
FOG WITH LIFR VSBYS WILL LIFT 13-14Z WITH THE TREND TOWARD VFR AT
ALL TAF SITES. ONLY CAVEAT MAY BE E COASTAL MA TERMINALS WHERE A
PERIOD OF MVFR CIGS MAY MOVE ACROSS THE AREA LATER THIS MORNING
AND AFTERNOON...ASSISTED BY AN EASTERLY SEA BREEZE. CONFIDENCE ON
THE TIMING OF THIS IS NOT HIGH. WINDS GENERALLY LIGHT...SHIFTING
TO THE N-NE MOST SITES.

TONIGHT...HIGH CONFIDENCE.
VFR WITH A LOW PROBABILITY OF PATCHY FOG IN INTERIOR MASSACHUSETTS
LATE.

THURSDAY...HIGH CONFIDENCE.
VFR. LOW PROBABILITY OF MVFR CIGS ALONG THE SOUTH COAST LATE IN
THE DAY.

KBOS TERMINAL...HIGH CONFIDENCE OVERALL BUT WITH MODERATE
CONFIDENCE IN TIMING OF CLEARING THIS MORNING.

KBDL TERMINAL...HIGH CONFIDENCE.

OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...

THU NIGHT INTO FRI NIGHT...MODERATE CONFIDENCE.
MAINLY VFR. SOUTHERLY FLOW. ALTHOUGH THU NIGHT AND EARLY FRI
NIGHT SOME PATCHY FOG IS POSSIBLE WITH LOCALLY LOWER CATEGORIES. A
BRIEF SHOWER NOT OUT OF THE QUESTION...BUT MOST RUNWAYS REMAIN
DRY.

LATE SAT INTO SUN...HIGH CONFIDENCE.
HIGH PRESSURE WITH VFR CONDITIONS. WINDS NNE...WITH E SEA BREEZES
LIKELY ALONG THE E COAST.

&&

.MARINE...
FORECASTER CONFIDENCE LEVELS...

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

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

TODAY...
HIGH PRESSURE BUILDS OVER NEW ENGLAND FROM CANADA. NORTH WINDS
BECOME NORTHEAST BUT ARE GENERALLY 15 KNOTS OR LESS. GUSTS TO 20
KNOTS POSSIBLE SOUTH OF NANTUCKET THIS MORNING. SEAS START THE DAY
NEAR 5 FEET ALONG THE OUTER EDGE OF OUR WATERS...BUT SHOULD
SUBSIDE DURING THE DAY. LINGERING SMALL CRAFT HEADLINES WILL
CONTINUE EAST OF CAPE COD THIS MORNING BUT EXPECT THESE WILL
EXPIRE LATER THIS MORNING.

TONIGHT AND THURSDAY...LIGHT EAST WINDS. WINDS INCREASE ON THE
SOUTHERN OUTER WATERS THURSDAY BUT REMAIN BELOW 25 KNOTS. DRY
WEATHER WITH GOOD VISIBILITY.

OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...

THU NIGHT INTO SAT...HIGH CONFIDENCE.
A PERIOD OF MAINLY QUIET BOATING WEATHER CONTINUES...ALTHOUGH
THERE REMAINS THE POSSIBILITY OF SOME RAINFALL/FOG OCCASIONALLY
MAINLY ACROSS THE SRN WATERS. WINDS MAINLY SOUTHERLY...WITH A
LIGHT SOUTHERLY SWELL AROUND 3-4FT POSSIBLE.

LATE DAY SAT INTO SUN...MODERATE CONFIDENCE.
MAINLY QUIET BOATING WEATHER CONTINUES ON THE E COASTAL WATERS.
ON THE SOUTH COASTAL WATERS...NNE FLOW MAY AT TIMES APPROACH 20-25
KT. A BUILDING SWELL OUT OF THE S...FROM A DEEPENING STORM SYSTEM
WELL SOUTH OF THE REGION MAY REACH 5-6 FT AT TIMES.
THEREFORE...MAY REQUIRE SMALL CRAFT ADVISORIES.

&&

.CLIMATE...
TUESDAY/S MAX TEMPERATURES WERE COLD AGAIN. A RECORD REPORT WAS
SENT FOR BOSTON.

MAX TEMPS AND RECORD LOW LEVELS FOR JUNE 2ND...

BOS...49...OLD RECORD WAS 50 IN 1946. SECOND DAY IN A ROW.
ORH...48...ONGOING RECORD IS 47 IN 1946.
PVD...51...ONGOING RECORD IS 47 IN 1907.
BDL...55...ONGOING RECORD IS 50 IN 1907.

&&

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...WTB/DOODY
NEAR TERM...WTB/NOCERA/DOODY
SHORT TERM...WTB
LONG TERM...DOODY
AVIATION...WTB/NOCERA/DOODY
MARINE...WTB/DOODY
CLIMATE...


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