FXUS61 KCAR 301339
AFDCAR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
839 AM EST MON NOV 30 2009
.UPDATE...SNOWFALL AMOUNTS ARE APPROACHING ADVISORY CRITERIA IN
LOCATIONS BETWEEN HOULTON AND PRESQUE ISLE...SO A WINTER WEATHER ADVISORY
HAS BEEN ISSUED. LIGHT SNOWFALL WILL CONTINUE INTO THE EARLY
AFTERNOON...WITH ACCUMULATIONS FAVORING AREAS NORTH OF HOULTON AND
ALONG/NEAR THE NEW BRUNSWICK BORDER.
.SYNOPSIS...
LOW PRESSURE WILL MOVE EAST ACROSS THE REGION TODAY. THE LOW WILL
MOVE QUICKLY EAST OF THE REGION LATER TODAY AND TONIGHT. A WEAK
RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE AREA TUESDAY AND
WEDNESDAY THEN STRONG LOW PRESSURE WILL APPROACH FROM THE
SOUTHWEST WEDNESDAY NIGHT AND MOVE ACROSS THE REGION ON THURSDAY.&&
.NEAR TERM /THROUGH TUESDAY/...
WE DO NOT HAVE ANY COMPELLING REASONS TO MAKE MUCH IN THE WAY OF
CHGS TO SN TOTALS TDY ACROSS THE N AND CNTRL PTNS OF THE FA...WITH
CURRENT RADAR IMAGERY SHOWING THE PRECIP TYPE TRANSITION ZONE ALG
ZONES 31...11 AND 32 TIER...WHERE THE GRIDS INDICATE IT SHOULD BE
ATTM. ALL MODEL GUIDANCE LIFTS THE TRANSITION ZONE TO SA FAR N AS
CNTRL ZONE 4 AND SRN PTNS OF ZONE 2 MIDDAY TIL ERLY AFT BEFORE
LLVL COLD ADVCN BEGINS TO BRING THE TRANSITION LINE BACK TO THE SE
ON THE BACK SIDE OF THE STEADY PRECIP SHIELD LATER THIS AFT AS THE
SFC LOW MOVES FROM E CNTRL ME INTO NEW BRUNSWICK.
IN ANY EVENT...STEADY PRECIP SHOULD TAPER TO SCT SHWRS W TO E
ACROSS THE FA DURG THE MID/LATE AFT HRS. WITH THE WARM FRONT
REACHING NWRD INTO INTERIOR DOWNEAST AREAS BY AFT...A CONSIDERABLE
GRADIENT OF HI TEMPS SHOULD EXIST BETWEEN CNTRL AND COASTAL AREAS
OF OUR FA.
SCT SN/RN SHWRS THIS EVE SHOULD END OR TAPER TO SCT FLURRIES BY
LATE TNGT AS LLVL COLD ADVCN CONTS...WITH ENOUGH DOWNSLOPE/
DOWNGLIDE FOR DOWNEAST AREAS TO EXPERIENCE PARTIAL CLRG LATE TNGT.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
AT THE SFC...WEAK RDG OF HGH PRES IS FCST TO BE BUILDING ACROSS THE
AREA BY ERLY TUE BEHIND SYSTEM AFFECTING THE FA TODAY...
ALOFT...XPCT THE H5 TROF TO SWING ACROSS THE AREA DURING THE DAY
TUE W/ A SECONDARY UPPER SHORT WAVE THEN FCST TO SLIDE SEWRD
ACROSS NRN AREAS LATE TUE/TUE EVE. THESE FEATURES MAY BE ENUF TO
TRIGGER SOME SCT SW- ACTION ACROSS FAVORED UPSLOPE AREAS OF NRN
AND WRN MAINE. THEREAFTER...RDG AT BTH THE SFC AND ALOFT IS XPCTD
TO STRENGTHEN LEADING TO RATHER BENIGN WX CONDS FROM TUE NGT THRU
WED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
IN THE LONG TERM...MODEL DIFFS PERSIST CONCERNING DEEP LOW PRES
FCST TO AFFECT THE FA LATER WED NGT THRU THU... THESE DIFFS
INVOLVE THE POTENTIAL PHASING OF THE NRN AND SRN ENERGY STREAMS W/
THE MAJORITY OF THE 00Z MODEL SUITE LEADING TO A PHASING OF THESE
ENERGY STREAMS OVR THE OH VALLEY AND A RESULTANT DEEP STORM SYSTEM
WHICH TRACKS W OF THE FA LATER THU THEN N AND NE OF THE REGION THU
NGT. THE CAN GEM AND ECMWF PREFER TO KEEP THESE ENERGY STREAMS
MORE SEPARATE RESULTING IN A WEAK NRN BRANCH LOW PASSING N OF THE
AREA WED NGT THEN A WEAKER SRN BRANCH SYSTEM WHICH TRACKS A BIT
FURTHER S AND E THAN THE OTHER MODELS SUGGEST. HOWEVER...EVEN THIS
FURTHER SRN TRACK OF THE SRN BRANCH SYSTEM SHOWS PLENTY OF WARM
AIR OVERSPREADING MUCH OF THE FA. AS A RESULT...HAVE TRENDED A BIT
HGHR ON TEMPS FOR THU AND XPCT ANY FROZEN/FREEZING PRECIP ERLY ON
TO CHANGE OVER TO MAINLY RAIN ALL BUT FAR NWRN AREAS... FAVORED
TRACK OF THIS SYSTEM SUGGEST A SIGNIFICANT RAIN AND WIND EVENT
COULD BE ON TAP FOR OUR AREA FOR THU.
BY THU NGT...XPCT THE SYSTEM TO SWEEP WELL NE OF THE AREA W/ BRISK
W WNDS USHERING IN MUCH CHILLIER AIR. MAINLY CYCLONIC FLOW SHOULD
KEEP A THREAT OF SW- GOING ACROSS FAVORED UPSLOPE AREAS ACROSS
NRN AND WRN MAINE INTO THE WEEKEND THO SIGNIFICANT PRECIP FROM THU
NGT ONWARD IS NOT XPCTD ATTM.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
MSLY IFR/MVFR CLGS/VSBYS XPCTD ACROSS THE TAF SITES TDY IN SN/RN
WITH IFR MOST LIKELY ACROSS NRN SITES WHERE LOWER VSBY WITH SNFL
WILL DOMINATE MOST. CONDITIONS SHOULD IMPROVE TO VFR TNGT ACROSS
DOWNEAST SITES AND AT LEAST HI MVFR OVR NRN TAF SITES. MAINLY
VFR CONDS XPCTD TUE AND WED W/ WDSPRD IFR FROM LATE WED NGT THRU
THU. MAINLY VFR CONDS RETURN FOR THU NGT AND PERSISTS THRU FRI.
&&
.MARINE...
NEAR TERM: WENT WITH AN SCA FOR OUTER COASTAL WATER ZONES 50 AND
51 FOR BOTH MARGINAL SEAS AND WINDS BEGINNING LATE THIS MORNING
AND CONTG AT LEAST THRU THE LATE NGT HRS TNGT. WIND GUSTS TO 25 KT
MAY STILL OCCUR AFT 09Z TNGT...BUT THE SCA CAN BE EXTENDED LATER
INTO TUE MORN LATER TDY...IF NEEDED. BOTH WINDS AND SEAS SHOULD
REMAIN BELOW SCA CRITERIA OVR THE INNER HARBOR ZONE. XPCT BLO SCA
CONDS THRU WED W/ GLW CONDS PSBL FROM LATE WED NGT THRU LATE
THU.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR
MEZ002-005-006.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR ANZ050-051.
&&
$$
UPDATE...CANTIN
