482  
FXUS61 KGYX 170459  
AFDGYX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAY ME  
1159 PM EST MON DEC 16 2024  
   
SYNOPSIS
 
 
SOUTH WINDS WILL BRING INCREASING MOISTURE TONIGHT WITH AREAS OF  
FLURRIES AND DRIZZLE DEVELOPING THROUGH MIDNIGHT. SOME OF THE  
NORTHERN PEAKS AND VALLEYS MAY BE BELOW FREEZING AS SEE SOME  
BRIEF FREEZING RAIN, BUT OTHERWISE RAIN IS EXPECTED FOR THE REST  
OF THE FORECAST AREA. A FRONT WILL SWEEP THROUGH EARLY TUESDAY  
AND BRING AN END TO PRECIPITATION FOR EVERYWHERE BUT THE  
MOUNTAINS, WHERE SNOW SHOWERS CONTINUE THROUGH THE DAY. THE  
SECOND HALF OF THE WEEK WILL FEATURE ANOTHER CHANCE FOR  
PRECIPITATION WITH A STRONGER STORM SYSTEM. A COLDER, SNOWIER  
STORM IS POSSIBLE WITH THIS ONE. THE COLDEST AIR OF THE SEASON  
MOVES IN FOR THE WEEKEND.  
 

 
   
NEAR TERM /THROUGH TUESDAY/
 
 
1155 PM UPDATE... LIGHT RAIN AND FOG CONTINUES OVER MUCH OF THE  
REGION WITH STILL SOME POCKETS OF LIGHT ICING POSSIBLE OVER  
WESTERN INTERIOR ME AND NORTH-CENTRAL NH. AS A RESULT, WILL  
CONTINUE THE ADVISORY FOR THESE AREAS BUT DID CANCEL IT FOR  
SOUTHWESTERN NH WHERE TEMPERATURES ARE NOW MOSTLY ABOVE  
FREEZING.  
 
PREVIOUSLY...  
640 PM UPDATE... AREA WEBCAMS SHOW THAT DRIZZLE ALONG WITH FOG  
HAS ALREADY DEVELOPED ACROSS SOUTHERN NH WITH WEATHER STATIONS  
SHOWING BOTH AIR AND ROAD TEMPERATURES NEAR THE FREEZING MARK.  
THEREFORE, WENT AHEAD AND EXPANDED THE WINTER WEATHER ADVISORY  
TO INCLUDE ALL OF NORTHERN NH ALONG WITH WESTERN NH FOR THE  
POTENTIAL OF A LIGHT GLAZE OF ICE. OTHERWISE, THE INHERITED  
FORECAST REMAINS LARGELY UNCHANGED AT THIS TIME.  
 
PREVIOUSLY...  
CLOUDS CONTINUE TO LOWER AND THICKEN THIS EVENING.  
PRECIP WILL GENERALLY BE VERY LIGHT THRU MIDNIGHT. THERE WILL  
BE WAVES OF EITHER DRIZZLE OR FLURRIES...DEPENDING ON THE DEPTH  
OF MOISTURE. THERE ARE SOME HIGH CLOUDS STREAMING OVER THE LOWER  
DECK...AND THIS IS LEADING TO A POTENTIAL FOR SEEDER-FEEDER  
MECHANISM TO LIMIT DRIZZLE. BUT OVERALL IT IS QUITE DRY  
ALOFT...ESPECIALLY IN THE SNOW GROWTH ZONE. TEMPS ALSO CONTINUE  
TO SLOWLY WARM UP...BUT SOME POCKETS OF SUB-FREEZING AIR REMAIN.  
SO AT LEAST AT ONSET SOME FREEZING RAIN OR FREEZING DRIZZLE IS  
LIKELY. I HAVE ISSUED A WINTER WEATHER ADVISORY FOR THE AREAS  
MOST LIKELY TO SEE A LIGHT GLAZE ON SURFACE BEFORE ANY WARMING  
OCCURS. ONE THING TO WATCH WILL BE ROAD SURFACE TEMPS. RECENT  
COLD WEATHER MAY LEAD TO ROAD SURFACES REMAINING BELOW FREEZING  
BRIEFLY DESPITE AIR TEMPS BEING ABOVE. THIS COULD LEAD TO RAIN  
FREEZING EVEN IF OBSERVING EQUIPMENT IS NOT REPORTING IT. THAT  
SHOULD NOT LAST LONG OVERNIGHT HOWEVER...WITH WAA EXPECTED TO  
LEAD TO A NON-DIURNAL TEMP TREND. I USED HI-RES GUIDANCE TO  
BLEND 2 M TEMPS UP THRU THE NIGHTTIME.  
 

 
   
SHORT TERM /TUESDAY NIGHT/
 
 
TUE MORNING THE FRONT/OCCLUSION WILL SWEEP THRU THE FORECAST  
AREA AND BRING AN END TO STEADY PRECIP RATHER QUICKLY FROM WEST  
TO EAST. UPSLOPING FLOW WILL LEAD TO SCATTERED MTN SNOW SHOWERS  
THRU MUCH OF THE REST OF THE DAY INTO THE EVENING...LIGHT  
ACCUMULATIONS ARE POSSIBLE.  
 
IT WILL AT LEAST BRIEFLY WARM UP AS THE LOW LEVEL COLD AIR IS  
MIXED OUT BEHIND THE FRONT...THEN A STEADY FALL IS EXPECTED THRU  
THE REST OF THE DAY. IT WILL ALSO BE BREEZY...BUT WIND GUSTS ARE  
GENERALLY ANTICIPATED TO BE LESS THAN 25 MPH. THE PRESSURE  
GRADIENT WILL KEEP THINGS MORE MIXED THAN NOT GOING INTO TUE  
NIGHT...SO TEMPS WILL BE WARMER THAN NORMAL FOR THIS TIME OF  
YEAR.  
 

 
   
LONG TERM /WEDNESDAY THROUGH MONDAY/
 
 
05Z LONG TERM FORECAST UPDATE... LITTLE CHANGE IN THE LATEST  
ENSEMBLE AND DETERMINISTIC GUIDANCE FOR A MID-WEEK QUICK HITTING  
SHOT OF PRECIPITATION ON WEDNESDAY NIGHT. THIS COULD BRING A  
COUPLE INCHES OF SNOW FOR AREAS AWAY FROM THE COAST WITH A  
RAIN/SNOW MIX ALONG THE COAST. BEHIND THIS SYSTEM COOLER  
TEMPERATURES WILL PREVAIL ALONG WITH PERHAPS SOME SNOW SHOWERS  
AT TIMES.  
 
PREVIOUSLY...  
OVERVIEW...  
 
AN ACTIVE PATTERN CONTINUES THROUGH THE MIDDLE AND LATER PORTIONS OF  
THE WORK WEEK WITH MULTIPLE CHANCES FOR RAIN OR SNOW. COLD WEATHER  
RETURNS FOR THE END OF THE WEEK AND NEXT WEEKEND AS A TROUGH DEEPENS  
ACROSS THE NORTHEAST.  
 
DETAILS...  
 
MILD WEATHER PRECEDES A SYSTEM ON WEDNESDAY WITH HIGHS MAINLY  
IN THE 40S OUTSIDE OF THE HIGHER TERRAIN. A SHORTWAVE SWINGS  
THROUGH THE OHIO VALLEY AND BY WEDNESDAY LOW PRESSURE DEEPENS AS  
IT LIKELY TRACKS ACROSS OR JUST SOUTH OF SOUTHERN NEW ENGLAND.  
WITH A LACK OF COLD AIR IN PLACE, A RAIN/SNOW LINE IS EXPECTED  
TO SET UP ACROSS THE COASTAL PLAIN WEDNESDAY NIGHT AND INTO  
EARLY THURSDAY. INTERIOR AND NORTHERN AREAS STAND THE BEST  
CHANCE TO PICK UP A LIGHT TO MODERATE SNOWFALL, WHILE THE COAST  
AND SOUTHERN NH LOOKS TO BE MOSTLY RAIN AT THIS POINT. THE  
SYSTEM MOVES AWAY THURSDAY MORNING, WITH HIGHS RANGING FROM NEAR  
30 ACROSS THE NORTH, TO THE MID 40S ALONG THE COAST.  
 
SEASONABLY COOL AIR RETURNS FOR FRIDAY, WITH HIGHS RANGING FROM THE  
LOW 20S ACROSS THE NORTH, TO THE MID 30S ALONG THE COASTLINE. WITH  
COLD AIR IN PLACE, WE THEN WATCH THE NEXT POTENTIAL SYSTEM FOR  
LATE FRIDAY AND FRIDAY NIGHT.  
 
MODELS CONTINUE TO DIVERGE GREATLY ON THIS SYSTEM FROM RUN TO RUN,  
AND SOMEWHAT BETWEEN DIFFERENT MODEL SUITES. THE OVERALL SET UP  
FEATURES AN ALBERTA CLIPPER MOVING EASTWARD THROUGH THE GREAT LAKES,  
AS RICH MOISTURE MOVES NORTHWARD OFF THE EAST COAST. THE  
DISCREPANCY CONTINUES TO BE WHETHER OR NOT THESE TWO FEATURES  
PHASE IN TIME TO BRING A SIGNIFICANT SNOWFALL TO THE AREA. AT  
THIS POINT THE MODELS ARE SUGGESTING THIS DOES NOT HAPPEN IN  
TIME, WITH ATLANTIC CANADA SEEING THE BRUNT OF A POWERFUL LOW  
PRESSURE SYSTEM. HOWEVER, THIS DOESN'T MEAN IT SHOULD BE RULED  
OUT YET, AS WE'RE STILL ABOUT 5 DAYS OUT. IT WOULD ONLY TAKE A  
SLIGHTLY MORE AMPLIFIED SHORTWAVE TO PHASE SOONER AND BRING A  
MORE SIGNIFICANT SNOWFALL TO THE AREA. ONE MODEL THAT DOES SHOW  
THIS HAPPENING A LITTLE SOONER AND BRINGING SNOW IT AT LEAST  
EASTERN AREAS IS THE NEW EURO AIFS MODEL. IT'S STILL TOO EARLY  
TO KNOW IF THIS IS JUST AN OUTLIER, OR THE START OF A TREND, BUT  
WE'LL NEED TO CONTINUE TO WATCH THIS SYSTEM FOR A COUPLE MORE  
DAYS BEFORE A HIGHER CONFIDENCE OUTCOME CAN BE REACHED.  
 
REGARDLESS OF THE DEVELOPMENT OF THE COASTAL LOW, AT LEAST SOME SNOW  
SHOWER ACTIVITY IS POSSIBLE LATE FRIDAY AS THE CLIPPER MOVES THROUGH  
NEW ENGLAND. BEHIND THIS SYSTEM, ARCTIC AIR POURS INTO NEW ENGLAND  
FOR NEXT WEEKEND, BRINGING THE COLDEST TEMPERATURES OF THE SEASON SO  
FAR. HIGHS IN THE TEENS AND 20S WITH LOWS IN THE SINGLE DIGITS TO  
BELOW ZERO LOOK INCREASINGLY LIKELY. IF THERE DOES END UP BEING A  
MORE WIDESPREAD SNOW COVER THESE TEMPERATURES WOULD GO EVEN LOWER,  
SO THIS IS ONE MORE REASON TO KEEP MONITORING THE FRIDAY SYSTEM.  
 

 
   
AVIATION /06Z TUESDAY THROUGH SATURDAY/
 
 
SHORT TERM...WIDESPREAD MVFR CONDITIONS CONTINUE TO MOVE  
NORTHWARD THRU THE FORECAST AREA AT THIS HOUR. GRADUALLY IFR  
CONDITIONS WILL CREEP IN FROM THE SOUTHWEST AND OVERSPREAD MOST  
OF THE TAF SITES BY MIDNIGHT AT THE LATEST ACROSS THE FARTHEST  
EAST AREAS. TEMPS APPEAR TO BE WARM ENOUGH THAT ANY PRECIP  
SHOULD BE RA THRU THE OVERNIGHT. THE ONE CONCERN MAY BE IF ROAD  
SURFACE TEMPS REMAIN SUB-FREEZING AFTER RECENT COLD WEATHER...A  
BRIEF ICE MAY FORM BEFORE MELTING WITH ADDITIONAL OVERNIGHT  
WARMING AND PRECIP. SOME LLWS IS LIKELY TONIGHT AROUND 1500 FT  
AS A LLJ SWEEPS NORTHWARD TOWARDS DAYBREAK. VFR CONDITIONS  
RETURN FOR ALL TAF SITES EXCEPT HIE ON TUE...WHERE LINGERING  
MVFR CIGS ARE LIKELY BECAUSE OF UPSLOPE FLOW.  
 
LONG TERM...VFR CONDITIONS ON WEDNESDAY GIVE WAY TO IFR TO LIFR  
AND RESTRICTIONS WEDNESDAY NIGHT WITH RAIN SOUTH AND SNOW  
NORTH. MVFR TO VFR RETURNS FOR THURSDAY AND INTO FRIDAY.  
CONDITIONS THEN BECOME DEPENDENT ON THE TRACK OF A STORM FOR  
LATE FRIDAY AND FRIDAY NIGHT, WITH COASTAL TERMINALS SEEING THE  
GREATEST CHANCE FOR RESTRICTIONS. VFR THEN LIKELY RETURNS FOR  
NEXT WEEKEND.  
 

 
   
MARINE
 
 
SHORT TERM...SOUTH WINDS CONTINUE TO GRADUALLY INCREASE TONIGHT.  
BRIEFLY AROUND SUNRISE WINDS OUTSIDE OF THE BAYS NORTH OF CAPE  
ELIZABETH MAY GUST TO GALE FORCE. A GALE WARNING HAS BEEN ISSUED  
FOR THESE ZONES...WITH SCAS IN EFFECT FOR ALL OTHER WATERS.  
WINDS AND SEAS WILL BE SLOW TO DIMINISH...LINGERING ABOVE SCA  
THRESHOLDS ESPECIALLY OUTSIDE OF THE BAYS THRU TUE NIGHT.  
 
LONG TERM...LOW PRESSURE CROSSES THE WATERS WEDNESDAY NIGHT,  
WITH WESTERLY WINDS POSSIBLY BRINGING SCA CONDITIONS BEHIND THE  
SYSTEM ON THURSDAY. CONDITIONS THEN BECOME DEPENDENT ON THE  
TRACK OF A DEVELOPING COASTAL LOW LATE FRIDAY. NORTHERLY GALES  
AND ARCTIC SEA SMOKE ARE THEN POSSIBLE OVER THE WEEKEND.  
 

 
   
GYX WATCHES/WARNINGS/ADVISORIES
 
 
ME...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR MEZ007>009-  
012-013-033.  
NH...WINTER WEATHER ADVISORY UNTIL 4 AM EST TUESDAY FOR NHZ001>006-  
009.  
MARINE...GALE WARNING FROM 4 AM TO 11 AM EST TUESDAY FOR ANZ150-152.  
SMALL CRAFT ADVISORY UNTIL 10 PM EST TUESDAY FOR ANZ151-153-  
154.  
 

 
 

 
 
NEAR TERM...TUBBS  
SHORT TERM...LEGRO  
LONG TERM...CLAIR/TUBBS  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab ME Page
The Nexlab NH Page Main Text Page