Woburn Weather Center  27.2°F

Area Forecast Discussion
National Weather Service Boston/Norton MA
629 AM EST Sat Dec 21 2024

SYNOPSIS
Mainly dry but blustery and very cold this weekend into early
next week. A weak clipper system may bring light snow
accumulations Christmas Eve, then mainly dry for the rest of the
Christmas week with temperatures moderating into the 30s and
low 40s.

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Updated: 4:25 AM

Key Messages:

* Light snow showers coming to an end by mid morning.

* Cloudy, cold, and breezy this afternoon. Cannot rule out a stray
  flurry or two, but otherwise dry.

An early morning look at regional radars show ongoing light snow due
to an approaching mid-level trough. High-res guidance indicates the
activity continues into mid morning, with a focus in Connecticut and
western Massachusetts. With CAA and drying aloft, there is little
QPF, perhaps a few hundredths of an inch. Any additional snow
accumulation is a few tenths of an inch.

This afternoon, cannot rule out festive flurries with the mid-level
trough overhead and shortwave energy rounding the base. With PWATs
falling between 0.1" and 0.2" this should lend more to periods of
clouds, strato-cu, with the occasional flurry. It will be quite cold
and breezy too. BUFKIT soundings have mixing of the boundary layer
up to 900mb and with forecast temperatures at 925mb -10C to -12C
will result in afternoon temperatures in the low 30s at the coast
and mid to upper 20s inland. Far northwest Massachusetts will be
colder in the teens. As mentioned, it will be breezy, northwest
gusts 20 to 30 mph. This will lead to apparent afternoon temps in
the upper single digits to mid teens.

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Updated: 4:25 AM

Key Messages:

* Very cold conditions tonight into Sunday. Minimum apparent
  temps near Cold Weather Advisory criteria across portions of
  SNE.

* Dry and sunny for Sunday, but there is potential for ocean effect
  snow showers reaching Cape Cod.

Tonight: 1035mb high builds across the Great Lakes, skies becoming
clear and gusts remain elevated. With CAA ongoing, overnight temps
fall into the single digits across most of the region and at the
coast temperatures are in the low to middle teens. With ongoing
gusts, the apparent minimum temperature overnight are below zero for
most locations, with exception of the islands.

Did hold off on the issuance of the Cold Weather Advisory. This is a
new product, replacing Wind Chill Advisory, now we are able to issue
related products for air temperature and/or wind chill when values
fall below to/below -10F in Connecticut, Rhode Island, and southeast
Massachusetts. For the remainder of Massachusetts the threshold is
-15F. Right now, the overnight minimum apparent temperature for
southern areas are -5F to -8F, while north it is -5F to -12F. In
Berkshire County, minimum apparent temperature lowers to/below the
threshold of -15F, WFO ALY has issued a Cold Weather Advisory for
the overnight hours. We will have to reassess today to see if we are
any closer to those thresholds. As previously mentioned, it is
borderline, but would not be surprised if the advisory is expanded
to the east slope of the Berkshire on the day shift.

Sunday: Very cold, 925mb temperatures settle between -16C and -20C
and with good mixing due to the CAA, should have highs in the teens
to low 20s at the coast, utilized the blend of the 25th and 50th
percentile of the NBM to achieve those temperatures. Gusts are not
as strong as they were on Saturday, generally up to 20 mph. The
apparent temperature mid afternoon is downright frigid, +5F to -5F!
While it is a mainly sunny day, PWATs plummet to less than 0.1" the
NNW wind direction over the relatively warmer eastern ocean waters,
could lead to ocean effect snow showers. High-res guidance shows
streamers moving towards the outermost Cape... added POPs here to
show the slight chance of snow.

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Key Messages:

* Rather cold and dry Sunday night into Monday but with less wind

* Temps recovering to near seasonable normals for the rest of the
  Christmas week

* Weak clipper system may bring minor snow accum late Mon night
  and Tue, especially in the interior

* Mainly dry Christmas Day through Fri

Sunday night and Monday...

Strong high pres ~1040 mb builds into New Eng which will bring
diminishing wind and mainly clear skies, although the northerly flow
and cold air over warmer SST will keep ocean effect clouds over the
outer Cape into Mon morning and perhaps a few flurries. Sunshine
Monday will gradually give way to increasing high clouds in the
afternoon as next system approaches from the west. Coldest night of
the season will be Sunday night as radiational cooling allows for
low dropping into the single numbers, possibly near zero NW MA, but
teens SE coastal MA and Cape/Islands where slightly more wind and
cloud cover, especially outer Cape. Highs Monday will recover into
the mid-upper 20s with lower 30s near the south coast.

Monday night and Tuesday...

Next mid level shortwave approaches from the Gt Lakes Mon night
moving across New Eng Tue. This will be accompanied by a weak
clipper system. There is uncertainty with the track of the low but
this is expected to be a light QPF event with potential for some
light snow accumulations late Mon night into Tue.  Any changeover to
rain near the south coast will depend on whether low tracks to the
north with a wind shift to south. Latest ensemble guidance
indicating high probs for 1 inch, especially in the interior. The
75th percentile of the GEFS and EPS distribution indicating
potential 1-2 inch accums which is probably a reasonable expectation
for this event. After a cold night Mon night temps will recover into
the 30s Tue.

Christmas Day through Friday...

High pres will be building to the north on Christmas and persisting
into Friday. This will result in mainly dry conditions, but
persistent NE flow may lead to more cloud cover across eastern New
Eng with low risk for a few showers at times. Near seasonable temps
expected.

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Forecast Confidence Levels:

Low - less than 30 percent.
Moderate - 30 to 60 percent.
High - greater than 60 percent.

Today...Moderate confidence.

MVFR conditions across western southern New England this morning
due to -SN passing through, visibilities are 3-5SM and ceilings
are 025-040. These conditions continue through 12z/14z. This
afternoon mainly VFR cigs, but lower MVFR cigs possible early
Cape/Islands. NW wind 10-20 kt with some higher gusts.

Tonight and Sunday...High confidence.

VFR, but ocean effect clouds may lower cigs to MVFR at times
over the outer Cape, mainly along and east of HYA. NW wind 10-20
kt with higher gusts near the coast, diminishing Sunday
afternoon.

KBOS TAF...High confidence in improving trend to VFR by 12z.

KBDL TAF...Moderate confidence.

Areas of -SN leading to MVFR conditions, should improve to VFR
by 13z/14z.

Outlook /Sunday Night through Wednesday/...

Sunday Night through Monday: VFR.

Monday Night through Tuesday: Mainly VFR, with local IFR
possible. Chance SN.

Tuesday Night: VFR. Slight chance SN.

Christmas Day: VFR.

.MARINE...
Forecaster Confidence Levels:
Low - less than 30 percent.
Medium - 30 to 60 percent.
High - greater than 60 percent.

Key Messages:

* Small Craft Advisory in effect through Sunday.

Saturday...High confidence.

Low pressure system lifts northeast from southern New England, but
with high pressure building to the west, it will lead to northwest
flow with gusts continuing throughout the day. Have extended the
Small Craft Advisory as a result through the day. Seas remain rough
3 to 6 feet on the southern waters and 5 to 8 feet on the eastern
waters.

Saturday night into Sunday...High confidence.

High pressure moving overhead. NW winds 15-20 kts gusting to 25
kts. Seas 5-7 ft. A few ocean effect snow showers are possible
Sunday across the eastern waters.

Outlook /Sunday Night through Wednesday/...

Sunday Night: Winds less than 25 kt. Areas of seas approaching
5 ft. Slight chance of snow showers.

Monday: Winds less than 25 kt.

Monday Night: Winds less than 25 kt. Chance of rain, chance of
snow. Local visibility 1 to 3 nm.

Tuesday: Winds less than 25 kt. Seas locally approaching 5 ft.
Chance of rain, chance of snow. Local visibility 1 to 3 nm.

Tuesday Night: Winds less than 25 kt. Seas locally approaching
5 ft. Chance of rain, chance of snow.

Christmas Day: Winds less than 25 kt. Areas of seas approaching
5 ft. Slight chance of rain showers.

.BOX WATCHES/WARNINGS/ADVISORIES...
CT...None.
MA...None.
RI...None.
MARINE...Small Craft Advisory until 7 AM EST Sunday for ANZ231-232-251.
     Small Craft Advisory until 10 PM EST this evening for
     ANZ233>235-237.
     Small Craft Advisory until 7 PM EST Sunday for ANZ250-254>256.

SYNOPSIS...KJC/Dooley
NEAR TERM...Dooley
SHORT TERM...Dooley
LONG TERM...KJC
AVIATION...KJC/Dooley
MARINE...KJC/Dooley          

Zone Forecast Product for Southern New England
National Weather Service Boston/Norton MA
1002 AM EST Sat Dec 21 2024

Forecast Synopsis
Mainly dry but blustery and very cold this weekend into early
next week. A weak clipper system may bring light snow
accumulations Christmas Eve, then mainly dry for the rest of the
Christmas week with temperatures moderating into the 30s and
low 40s.

Southeast Middlesex MA-
Including the city of Cambridge
1002 AM EST Sat Dec 21 2024

.THIS AFTERNOON...Partly sunny. Cold with highs in the upper 20s.
Northwest winds 10 to 15 mph with gusts up to 30 mph.
.TONIGHT...Mostly clear. Colder with lows around 11. Northwest
winds around 10 mph with gusts up to 25 mph.
.SUNDAY...Sunny, colder with highs around 17. Northwest winds
around 10 mph with gusts up to 20 mph.
.SUNDAY NIGHT...Clear, cold with lows around 8 above. Northwest
winds 5 to 10 mph.
.MONDAY...Sunny, cold with highs in the mid 20s. Northwest winds
around 5 mph, becoming southwest around 5 mph in the afternoon.
.MONDAY NIGHT AND TUESDAY...Snow likely. Lows around 20. Highs in
the mid 30s. Chance of snow 60 percent.
.TUESDAY NIGHT...Mostly cloudy. Lows in the mid 20s.
.CHRISTMAS DAY THROUGH THURSDAY NIGHT...Partly cloudy. Highs in
the mid 30s. Lows in the mid 20s.
.FRIDAY...Mostly sunny. Highs in the lower 40s.          

REGIONAL WEATHER ROUNDUP
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
1100 AM EST SAT DEC 21 2024

NOTE:  "FAIR" INDICATES FEW OR NO CLOUDS BELOW 12,000 FEET WITH NO
SIGNIFICANT WEATHER AND/OR OBSTRUCTIONS TO VISIBILITY.

MAZALL-211700-
EASTERN MASSACHUSETTS

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
BOSTON         PTSUNNY   28  17  63 W18G25    29.90F WCI  15
BEVERLY        MOSUNNY   26  16  65 NW15      29.88F WCI  14
LAWRENCE       CLOUDY    26  14  60 NW8G22    29.91F WCI  18
BEDFORD        CLOUDY    27  16  63 NW16G24   29.90S WCI  15
NORWOOD        CLOUDY    29  19  66 NW8       29.90F WCI  21
MARSHFIELD     MOSUNNY   30  21  69 W8G21     29.88F WCI  23
PLYMOUTH       CLOUDY    29  22  75 NW12G18   29.87F WCI  19
TAUNTON        LGT SNOW  30  22  72 NW9G16    29.89F WCI  22
NEW BEDFORD    CLOUDY    30  23  75 NW10G20   29.88F WCI  21


MAZALL-211700-
CAPE COD AND THE ISLANDS

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
FALMOUTH       MOSUNNY   30  25  80 NW10      29.88F WCI  21
HYANNIS        MOSUNNY   30  24  78 NW12G21   29.84F WCI  20
CHATHAM        CLOUDY    33  23  66 VRB6      29.85F WCI  28
PROVINCETOWN   CLOUDY    31  24  75 NW17      29.86F WCI  19
NANTUCKET      MOSUNNY   32  25  75 NW15G24   29.86F WCI  22
MARTHAS VNYRD  MOSUNNY   30  23  75 NW13G22   29.88F WCI  20


MAZALL-211700-
CENTRAL AND WESTERN MASSACHUSETTS

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
WORCESTER      CLOUDY    24  13  62 NW18G26   29.86F WCI  10
FITCHBURG      CLOUDY    26  12  55 NW21G31   29.92S WCI  12
ORANGE         MOSUNNY   24  10  55 N17G28    29.95R WCI  11
SPRINGFIELD    PTSUNNY   27  13  56 NW20      29.93S WCI  14
WESTFIELD      CLOUDY    27  12  53 N18G24    29.96F WCI  14
NORTH ADAMS    LGT SNOW  20  13  74 W9        29.99F WCI   9
PITTSFIELD     LGT SNOW  19  12  74 NW10      29.94S WCI   7


RIZALL-211700-
RHODE ISLAND

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
PROVIDENCE     LGT SNOW  29  22  75 NW14      29.91F WCI  18
NEWPORT        CLOUDY    30  23  75 NW10      29.89F WCI  21
BLOCK ISLAND   FLURRIES  30  25  81 NW15G22   29.91F WCI  19
SMITHFIELD     FLURRIES  27  21  78 NW12G20   29.89F WCI  17
WESTERLY       CLOUDY    29  23  78 VRB7G17   29.91F WCI  22


CTZALL-211700-
CONNECTICUT

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
BRADLEY INTL   CLOUDY    30  13  49 NW10G22   29.97F WCI  21
HARTFORD       CLOUDY    29  14  53 NW15G26   29.98S WCI  18
PLAINVILLE     CLOUDY    27  16  63 NW10G24   29.98S WCI  17
BRIDGEPORT     CLOUDY    29  19  66 NW20G26   30.00S WCI  16
DANBURY        PTSUNNY   27  15  61 N13G23    30.01S WCI  16
GROTON         CLOUDY    30  25  81 NW13      29.92F WCI  20
NEW HAVEN      CLOUDY    31  19  61 N12G24    29.98F WCI  22
CHESTER        MOSUNNY   28  19  69 NW17G24   29.93S WCI  16
MERIDEN          N/A     30  16  56 NW16G29   29.98F WCI  19
WILLIMANTIC    CLOUDY    27  20  75 NW13G21   29.94S WCI  16
OXFORD         PTSUNNY   24  15  68 NW14G30   29.96F WCI  12


MEZ002-015-021-024-NHZ003-005-008-011-012-014-VTZ005-008-211700-
NORTHERN NEW ENGLAND

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
PORTLAND ME    MOSUNNY   27  11  51 NW15G26   29.85F WCI  15
BANGOR ME      LGT SNOW  23  18  81 NW12      29.79F VSB 1   WCI  12
CONCORD NH     CLOUDY    22  11  62 NW17G30   29.91S WCI   8
MANCHESTER NH  PTSUNNY   26  11  52 NW18G30   29.89F WCI  13
NASHUA NH      CLOUDY    26  16  65 NW21G28   29.91F WCI  12
PORTSMOUTH NH  PTSUNNY   28  13  53 W13       29.86F WCI  18
JAFFREY NH     PTSUNNY   21  11  65 NW9G20    29.88S WCI  11
KEENE NH       CLOUDY    23  12  62 N21G26    29.94F WCI   8
BURLINGTON VT  LGT SNOW  17  10  74 N16G24    30.07S VSB 3/4 WCI   2
MT. WASHINGTON BLWGSNOW  -4  -4 100 NW25G45     N/A  VSB 1/16WCI -30


NYZ052-076-211700-
EASTERN NEW YORK

CITY           SKY/WX    TMP DP  RH WIND       PRES   REMARKS
ALBANY         PTSUNNY   21  12  68 W16G24    30.06F WCI   7
NEW YORK CITY  PTSUNNY   31  16  54 NW21G29   30.04R WCI  18


ANZALL-211700-
MARINE OBSERVATIONS

STATION/POSITION TIME  TEMP    WIND        PRES    VSBY  WAVE
                       AIR SEA DIR/SP/G                  HT/PER
                 (UTC) (F)     (DEG/KT/KT) (MB)    (MI)  (FT/S)
BOSTON BUOY      1550   29 47  310/ 16/ 21 1012.0F         9/ 9
BUZZARDS BAY     1500   33     330/ 15/ 18 1013.0R
NANTUCKET SOUND  1540   31 43  310/ 14/ 19 1010.8F
MASS BAY-STELLWA 1404   30     320/ 16/ 21 1010.9R  1 7/8  9/ 8
ISLE OF SHOALS   1500   26     300/ 15/ 18 1011.2R
S OF BLOCK IS    1556      52                N/A           5/10


......................KEY.........................
  SKY/WX - SKY CONDITION/PRESENT WEATHER
  TMP    - TEMPERATURE IN FAHRENHEIT
  DWPT   - DEWPOINT IN FAHRENHEIT
  RH     - RELATIVE HUMIDITY IN PERCENT
  WIND   - DIRECTION AND SPEED IN MPH
  PRES   - MEAN SEA LEVEL PRESSURE IN INCHES OF HG
  WCI    - WIND CHILL INDEX
  VSB    - VISIBILITY IN MILES
  HX     - HEAT INDEX
  TC     - TEMPERATURE IN CELSIUS
  VRB    - VARIABLE WIND DIRECTION
  N/A    - NOT AVAILABLE          

Max/Min Temperature and Precipitation Table for
Most of Southern New England
National Weather Service Boston/Norton MA
720 AM EST Sat Dec 21 2024

This is an automated product. These data are preliminary and have not
undergone final quality control by the National Climatic Data Center
(NCDC). Therefore, these data are subject to revision. Final and
certified climate data can be accessed at www.ncdc.noaa.gov.


Values represent highs yesterday, lows over the last 12 hours
and precipitation over the last 24 hours.

.BR BOX 1221 ES DH00/TAIRZX/DH07/TAIRZP/PPDRZZ

                          Max      Min      24 Hour
ID   Location             Temp     Temp   Precipitation

Eastern Massachusetts...
BED   Bedford             32   /    23   /    0.04
BVY   Beverly             33   /    19   /    0.15
BOS   Boston              37   /    25   /    0.51
LWM   Lawrence            30   /    22   /    0.09
EWB   New Bedford         43   /    25   /    0.31
OWD   Norwood             36   /    24   /    0.07
PYM   Plymouth            40   /    24   /    0.61
GHG   Marshfield          39   /    27   /

Cape Cod and the Islands...
CQX   Chatham             44   /    33   /    0.63
HYA   Hyannis             42   /    30   /    0.58
MVY   Marthas Vineyard    44   /    27   /    0.43
ACK   Nantucket           45   /    33   /    0.57
FMH   Falmouth            43   /    25   /
PVC   Provincetown        41   /    31   /

Central and Western Massachusetts...
FIT   Fitchburg           30   /    20   /      T
ORE   Orange              30   /    24   /    0.03
CEF   Springfield         34   /    26   /    0.06
BAF   Westfield           32   /    26   /      T
ORH   Worcester           29   /    23   /    0.09

Rhode Island...
BID   Block Island        40   /    27   /
SFZ   Smithfield          32   /    22   /
UUU   Newport             42   /    27   /    0.26
PVD   Providence          35   /    26   /    0.17
WST   Westerly            37   /    27   /    0.03

Northern Connecticut...
BDL   Hartford-Bradley    34   /    29   /    0.04
HFD   Hartford            34   /    28   /    0.01
IJD   Willimantic         33   /    26   /      T