611  
FXUS61 KBOX 041954  
AFDBOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE BOSTON/NORTON MA  
254 PM EST SUN DEC 4 2022  
   
SYNOPSIS
 
 
DRY AND CHILLY WEATHER TONIGHT, WITH A WARMING TREND MONDAY THROUGH  
MID WEEK. BREEZY WITH RAIN TUESDAY THROUGH LATE WEDNESDAY. DRIER  
ON THURSDAY. TEMPERATURES TRENDING MORE SEASONABLE LATE THIS  
WEEK THROUGH THE WEEKEND.  
 

 
   
NEAR TERM /UNTIL 6 AM MONDAY MORNING/
 
 
HIGH PRESSURE WILL PASS BY SOUTHERN NEW ENGLAND TONIGHT. THIS  
WILL RESULT IN WINDS BECOMING LIGHT AND VARIABLE. ALREADY SEEING  
SOME HIGH LEVEL CLOUDS OVERSPREADING OUR REGION, SO NOT  
EXPECTING IDEAL RADIATIONAL COOLING CONDITIONS. THAT SAID, DID  
FAVOR THE LOWER END OF THE TEMPERATURE GUIDANCE, WITH LOW  
TEMPERATURES ABOUT 10-15 DEGREES LOWER THAN THIS MORNING. THE  
MORE URBANIZED AREAS WILL NOT COOL OFF QUITE AS MUCH, BUT SHOULD  
STILL BE COLDER THAN THIS MORNING.  
 

 
   
SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/
 
 
HIGH PRESSURE TO OUR EAST CONTINUES TO MOVE OFFSHORE DURING THE  
DAY. EXPECTING A LIGHT SOUTH TO SOUTHWEST WIND TO DEVELOP DURING  
THE DAY, WHICH THEN SHOULD BECOME SOUTH TO SOUTHEAST MONDAY  
NIGHT. THE COLD START, COUPLED WITH THE LOW DECEMBER SUN ANGLE,  
WILL LIMIT THE WARMING AT THE SURFACE. NONETHELESS, STILL  
EXPECTING HIGH TEMPERATURES TO BE SLIGHTLY ABOVE NORMAL.  
 
INCREASING CLOUDINESS MONDAY NIGHT AHEAD OF A COLD FRONT, WITH A  
SERIES OF WEAK SHORTWAVES. STILL ANTICIPATING DRY CONDITIONS FOR  
JUST ABOUT ALL OF OUR REGION. THE LOWER LEVELS SHOULD BE QUITE  
DRY, AND IT WILL TAKE SOME TIME TO INCREASE HUMIDITY TO THE  
POINT WHERE PRECIPITATION WILL REACH THE GROUND. CONFINED  
RAINFALL CHANCES MAINLY WEST OF THE CT RIVER VALLEY LATE MONDAY  
NIGHT.  
 

 
   
LONG TERM /TUESDAY THROUGH SATURDAY/
 
 
HIGHLIGHTS  
 
* UNSETTLED TUESDAY THROUGH LATE WEDNESDAY WITH RAIN. MAY BE A BIT  
BREEZY AT TIMES WITH WARMER THAN NORMAL TEMPS.  
 
* DRIER ON THURSDAY AND A BIT COOLER, BUT TEMPS STILL ROUGHLY 5  
DEGREES WARMER THAN NORMAL.  
 
* CONFIDENCE LOWERS SIGNIFICANTLY LATE IN THE WEEK THROUGH THE  
WEEKEND. HIGHER CONFIDENCE IN TEMPERATURES TRENDING NEAR TO COOLER  
THAN NORMAL.  
 
TUESDAY THROUGH WEDNESDAY...  
 
CYCLONIC FLOW IN PLACE THROUGH THIS PERIOD. WILL HAVE TWO SHORTWAVES  
LIFT THROUGH WELL TO THE NORTHWEST OF OUR REGION. THE FIRST MOVES  
FROM THE CENTRAL GREAT LAKES EARLY ON TUESDAY INTO CENTRAL QUEBEC BY  
LATE TUESDAY. THE NEXT SHORTWAVE LIFTS FROM THE MID/UPPER  
MISSISSIPPI RIVER VALLEY LATE ON TUESDAY INTO SOUTHERN/EASTERN  
QUEBEC BY LATE WEDNESDAY. LOW PRESSURE WILL LIFT ACROSS CENTRAL AND  
NORTHERN QUEBEC ON TUESDAY, WHICH WILL LIFTS A PSEUDO WARM FRONT  
INTO OUR REGION WHILE THE COLD FRONT SLIDES INTO THE EASTERN GREAT  
LAKES. A BROAD LOW DEVELOPS OVER THE MID ATLANTIC ON WEDNESDAY AND  
LIFTS NORTHEASTWARD, WHICH WILL PUSH THE COLD FRONT THROUGH LATER ON  
WEDNESDAY.  
 
MAIN CONCERN DURING THIS PERIOD IS THE POTENTIAL FOR STRONG WIND  
GUSTS LATE ON TUESDAY THROUGH WEDNESDAY AS A S/SSW 30-40 KT LOW  
LEVEL JET SLIDES THROUGH AT 925 HPA. STILL APPEARS THAT WE HAVE  
ROUGHLY A 1-2 STD ABOVE MODEL CLIMATOLOGY WITH THE NAEFS FOR WIND  
SPEED DURING THIS PERIOD. THINK THAT THE RISK FOR THE STRONGEST WIND  
GUSTS WILL BE ON WEDNESDAY AS JET IS SLIDING ACROSS THE REGION AND  
AS THE COLD FRONT IS SLIDING THROUGH. SINCE YESTERDAY CONFIDENCE IS  
LOWERING ON THE RISK OF STRONG WINDS THROUGH THIS PERIOD AS BUFKIT  
SOUNDINGS CONTINUE TO SHOW AN INVERSION IN PLACE PER THE GFS/NAM  
GUIDANCE. STILL MAY BE A BIT BREEZY AT TIMES GIVEN THE TIGHTENED  
PRESSURE GRADIENT, BUT APPEARING THAT IT WILL BE DIFFICULT TO TAP  
INTO THE STRONGER WINDS ALOFT.  
 
SHOULD SEE ANYWHERE FROM 0.5 TO 1.5 INCHES OF RAINFALL THROUGH THIS  
PERIOD. AT THIS POINT AM THINKING THAT THE HEAVIEST RAINS WILL BE  
LATE ON TUESDAY UNTIL ROUGHLY WEDNESDAY AFTERNOON FROM WEST TO EAST.  
THIS COINCIDES WITH THE UPTICK IN THE S/SSW LOW LEVEL JET SLIDING  
THROUGH AND PWATS INCREASING TO ROUGHLY 1-1.25 INCHES. THIS IS  
ROUGHLY BETWEEN THE 90TH AND MAX PER SPC SOUNDING CLIMATOLOGY FOR  
CHH.  
 
TEMPERATURES WILL CLIMB ABOVE NORMAL DUE TO SOUTHERLY WARM AIR  
ADVECTION. EXPECT TEMPERATURES TO CLIMB TO ROUGHLY 5-8 DEGREES  
CELSIUS ON TUESDAY AND 7-11 DEGREES ON WEDNESDAY. SHOULD SEE FAIRLY  
WIDESPREAD 50S ON BOTH DAYS WITH WEDNESDAY BEING THE WARMER OF THE  
TWO DAYS. NOT COMPLETELY OUT OF THE QUESTION A FEW SPOTS IN THE  
MERRIMACK AND CT RIVER VALLEY APPROACH 60 DEGREES ON WEDNESDAY.  
 
THURSDAY...  
 
CYCLONIC FLOW BEGINNING TO BREAK DOWN AS WE START TO SEE A PATTERN  
CHANGE. THIS IS A RESULT OF THE TROUGH LIFTING OUT OF THE  
SOUTHWESTERN US INTO THE CENTRAL US/MID MISSISSIPPI RIVER VALLEY.  
AHEAD OF THIS FEATURE WE WILL HAVE A RIDGE BUILD FROM THE MID  
MISSISSIPPI RIVER VALLEY INTO THE EASTERN GREAT LAKES. HIGH PRESSURE  
WILL NUDGE INTO THE REGION FROM ONTARIO/QUEBEC.  
 
STILL COULD SEE A FEW LINGERING SHOWERS ACROSS EASTERN PORTIONS OF  
SOUTHERN NEW ENGLAND EARLY ON THURSDAY AS THE COLD FRONT MAY STILL  
BE EXITING. WILL BE A DRIER AND COOLER AS FLOW SHIFTS TO THE NW/N.  
SOME UNCERTAINTY ON THE EXACT TEMP READINGS GIVEN MODELS ARE SPREAD  
IN THE AIRMASS IN PLACE ALOFT. GIVEN THE UNCERTAINTY HAVE STUCK WITH  
THE NBM. THIS KEEPS TEMPS RANGING FROM THE MID 40S TO THE MID 50S.  
 
FRIDAY THROUGH THE WEEKEND...  
 
CONFIDENCE LOWERS SIGNIFICANTLY DURING THIS PERIOD DUE TO THE TROUGH  
LIFTING IN FROM THE CENTRAL US/MID MISSISSIPPI RIVER VALLEY. QUITE A  
BIT OF SPREAD AMONGST DETERMINISTIC GUIDANCE WITH THE INTENSITY AND  
PROGRESSION OF THIS FEATURE AS IT SLIDES IN.  
 
AT THIS POINT APPEARS THAT THERE WILL BE A LEAST SOME PRECIPITATION  
PER CLUSTER ANALYSIS OF ENSEMBLE GUIDANCE. THE MAIN SOURCE OF  
VARIANCE IS HOW DEAMPLIFIED/AMPLIFIED THE RIDGE IS OVER NOVA SCOTIA  
AND THE SECONDARY IS THE EXACT POSITION OF THE RIDGE. DOES APPEAR  
THAT THERE WILL BE AT LEAST SLIGHT CHANCES TO CHANCES OF  
PRECIPITATION THROUGH THIS TIMEFRAME AS THE MAJORITY OF ENSEMBLE  
MEMBERS FEATURE THIS. WILL NOTE THAT THERE ARE A HANDFUL OF MEMBERS  
IN THE EPS/GEFS AND GEPS GUIDANCE THAT HAVE A SIMILAR FEEL OF THE  
LATEST OPERATIONAL GFS, BUT IT IS STILL MUCH TOO EARLY TO LATCH ONTO  
THIS GIVEN THE SPREAD AMONGST GUIDANCE. DUE TO THIS HAVE JUST STUCK  
WITH THE NBM. THIS KEEPS TEMPS NEAR TO SLIGHTLY COOLER THAN  
SEASONABLE.  
 

 
   
AVIATION /20Z SUNDAY THROUGH FRIDAY/
 
 
FORECASTER CONFIDENCE LEVELS:  
 
LOW - LESS THAN 30 PERCENT.  
MEDIUM - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
TONIGHT AND MONDAY...HIGH CONFIDENCE.  
 
VFR THROUGH MONDAY. W TO NW WINDS BECOMING LIGHT AND VARIABLE  
TONIGHT. S TO SW WINDS DEVELOPING MONDAY.  
 
MONDAY NIGHT...MODERATE CONFIDENCE.  
 
MAINLY VFR, WITH AREAS OF MVFR OR LOCAL IFR POSSIBLE ACROSS THE  
HIGHER TERRAIN. WINDS BECOMING S TO SE.  
 
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.  
 
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.  
 
OUTLOOK /TUESDAY THROUGH THURSDAY/...  
 
MONDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.  
SLIGHT CHANCE FZRA.  
 
TUESDAY: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY. CHANCE  
RA.  
 
TUESDAY NIGHT: MAINLY VFR, WITH AREAS IFR POSSIBLE. BREEZY. RA.  
 
WEDNESDAY: MVFR/IFR CONDITIONS POSSIBLE. BREEZY. RA.  
 
WEDNESDAY NIGHT: MAINLY VFR, WITH LOCAL IFR POSSIBLE. BREEZY.  
CHANCE RA.  
 
THURSDAY: VFR. BREEZY.  
 

 
   
MARINE
 
 
FORECASTER CONFIDENCE LEVELS:  
 
LOW - LESS THAN 30 PERCENT.  
MEDIUM - 30 TO 60 PERCENT.  
HIGH - GREATER THAN 60 PERCENT.  
 
HIGH CONFIDENCE. RELATIVELY LIGHT WINDS AND SEAS FOR EARLY  
DECEMBER AS A HIGH PRESSURE MOVES OVER THE WATERS TONIGHT, THEN  
FARTHER OFFSHORE MONDAY. A FEW WIND GUSTS COULD APPROACH 25 KT  
ACROSS THE EASTERN COASTAL WATERS MONDAY AFTERNOON. SEAS  
CONTINUE TO SUBSIDE, SO ANTICIPATING BEING ABLE TO LOWER SMALL  
CRAFT ADVISORIES LATER TODAY.  
 
OUTLOOK /TUESDAY THROUGH THURSDAY/...  
 
MONDAY NIGHT: WINDS LESS THAN 25 KT.  
 
TUESDAY: WINDS LESS THAN 25 KT. AREAS OF SEAS APPROACHING 5 FT.  
CHANCE OF RAIN.  
 
TUESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. RAIN  
LIKELY.  
 
WEDNESDAY: LOW RISK FOR SMALL CRAFT ADVISORY WINDS WITH GUSTS  
UP TO 25 KT. SEAS UP TO 5 FT. RAIN.  
 
WEDNESDAY NIGHT: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT. CHANCE  
OF RAIN.  
 
THURSDAY: WINDS LESS THAN 25 KT. SEAS UP TO 5 FT.  
 

 
   
BOX WATCHES/WARNINGS/ADVISORIES
 
 
CT...NONE.  
MA...NONE.  
RI...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ250-  
254>256.  
 

 
 

 
SYNOPSIS...BELK/BL  
NEAR TERM...BELK  
SHORT TERM...BELK  
LONG TERM...BL  
AVIATION...BELK/BL  
MARINE...BELK/BL  
 
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