Post by Ritty77 on Nov 3, 2012 9:19:57 GMT -5
Coastal low/Nor'easter expected Wednesday night into Thursday. Rain and wind along the coast, heavy snow inland as cold air will be in place. Central PA in the crosshairs.
.LONG TERM /MONDAY THROUGH SATURDAY/...
***MID-WEEK NOR`EASTER NEAR THE MID-ATLANTIC COAST***
MADE NO SIGNIFICANT CHANGES TO THE PRELIM MEDIUM RANGE GRIDS...WHICH
WERE DERIVED USING A 50/50 BLEND OF THE PREVIOUS FCST WITH THE
03/00Z EUROPEAN CENTRE GUIDANCE. ALL OF THE 03/12Z GLOBAL MODELS -
GFS/UKMET/CANADIAN/ECMWF - INDICATE A LARGE CYCLONE LIFTING NWD OVER
THE WESTERN ATLANTIC NEAR THE MID-ATLANTIC COAST WED-THUR...WITH THE
MAIN DIFFERENCES IN THE INTENSITY AND EXACT TRACK OF THE COASTAL LOW.
THE MILLION DOLLAR QUESTION REMAINS...HOW CLOSE TO THE COAST ?
THE PHASING OF MID-UPPER ENERGY WILL PLAY A CRUCIAL ROLE IN
DETERMINING THE FINAL OUTCOME...AND ULTIMATELY THE LOW TRACK.
UNFORTUNATELY FOR THE MODELS...THEY HAVE CONSIDERABLE DIFFICULTY IN
HANDLING THE PHASING OF S/W ENERGY ESPECIALLY AT LONGER RANGES.
THEREFORE ANTICIPATE SOME FUTURE WEST/EAST WAFFLING AND CONTINUING
UNCERTAINTY WITH THE LOW TRACK. THE MAIN TAKEAWAY OR BOTTOM-LINE
AT THIS POINT IS THAT THERE IS HIGH CONFIDENCE IN A MID-WEEK
NOR`EASTER NEAR THE MID-ATLANTIC COAST...BUT AS USUAL THE DETAILS
AND POTENTIAL IMPACTS WILL NEED TO BE REFINED/RESOLVED WITH FUTURE
MODEL RUNS AT SHORTER TIME INTERVALS. A STORM TRACK CLOSE THE
COAST WOULD FAVOR SNOWS OVER THE INTERIOR OF PA AND PERHAPS EVEN
AT LOWER ELEVATIONS. THE 03/12Z DETERMINISTIC ECMWF REMAINS THE
THE MOST BULLISH ON THIS SCENARIO.
GIVEN THE CONTINUATION OF THE BLOCKING PATTERN AND NEGATIVE
NAO...ALTHOUGH NOT QUITE AS PROMINENT AS LAST WEEK...PREFER TO LEAN
TOWARD THE ECMWF GUIDANCE...PARTICULARLY THE ENSEMBLE PRODUCTS...
WHICH HANDLED THE COMPLEX INTERACTION BTWN THE DIGGING H5 SYSTEM INTO
THE SERN STATES AND SANDY MUCH BETTER THAN THE OTHER GLOBAL MODEL
AND ENSEMBLE SYSTEMS ESPECIALLY IN THE MEDIUM RANGE/BEYOND 72HRS.
WHILE THE DETAILS REMAIN UNCLEAR...FELT THAT AN INCREASE IN POPS/QPF
WAS JUSTIFIED FOR DAYS 4-5 /WED-THUR/ OVER CENTRAL AND ERN SXNS WITH
THE POTENTIAL FOR ACCUMULATING SNOWS MAINLY OVER THE INTERIOR OF
CENTRAL PA. THERMAL PROFILES LOOK MARGINAL SO ELEVATION WOULD LKLY BE
A FACTOR. FOR NOW WILL SIMPLY MENTION RAIN OR SNOW PTYPES IN THE
GRIDS AND TEXT FORECAST UNTIL A CONSENSUS SOLUTION EMERGES.
OUTSIDE OF THE POTENTIAL HIGH-IMPACT WINTRY WEATHER FOR THE MID-WEEK
PERIOD...THE REMAINDER OF THE FCST LOOKS TRANQUIL AND DRY. HIGH PRES
SHOULD ENSURE FAIR/DRY CONDITIONS WITH BLW NORMAL TEMPS EARLY IN THE
WEEK /INCLUDING ELECTION DAY/ BEFORE RETREATING NEWD INTO NEW
ENGLAND. COLD AND BLUSTERY CONDS WOULD BE EXPECTED LATE NEXT WEEK
ON THE BACKSIDE OF THE DEEP LOW MOVG TWD SRN NEW ENGLAND. 500 HPA
HEIGHTS ARE FORECAST TO RISE ABOVE NORMAL INTO THE WEEKEND...SUPPORTING
A SIGNIFICANT MODERATION IN DAILY MAX/MIN TEMPS.
.LONG TERM /MONDAY THROUGH SATURDAY/...
***MID-WEEK NOR`EASTER NEAR THE MID-ATLANTIC COAST***
MADE NO SIGNIFICANT CHANGES TO THE PRELIM MEDIUM RANGE GRIDS...WHICH
WERE DERIVED USING A 50/50 BLEND OF THE PREVIOUS FCST WITH THE
03/00Z EUROPEAN CENTRE GUIDANCE. ALL OF THE 03/12Z GLOBAL MODELS -
GFS/UKMET/CANADIAN/ECMWF - INDICATE A LARGE CYCLONE LIFTING NWD OVER
THE WESTERN ATLANTIC NEAR THE MID-ATLANTIC COAST WED-THUR...WITH THE
MAIN DIFFERENCES IN THE INTENSITY AND EXACT TRACK OF THE COASTAL LOW.
THE MILLION DOLLAR QUESTION REMAINS...HOW CLOSE TO THE COAST ?
THE PHASING OF MID-UPPER ENERGY WILL PLAY A CRUCIAL ROLE IN
DETERMINING THE FINAL OUTCOME...AND ULTIMATELY THE LOW TRACK.
UNFORTUNATELY FOR THE MODELS...THEY HAVE CONSIDERABLE DIFFICULTY IN
HANDLING THE PHASING OF S/W ENERGY ESPECIALLY AT LONGER RANGES.
THEREFORE ANTICIPATE SOME FUTURE WEST/EAST WAFFLING AND CONTINUING
UNCERTAINTY WITH THE LOW TRACK. THE MAIN TAKEAWAY OR BOTTOM-LINE
AT THIS POINT IS THAT THERE IS HIGH CONFIDENCE IN A MID-WEEK
NOR`EASTER NEAR THE MID-ATLANTIC COAST...BUT AS USUAL THE DETAILS
AND POTENTIAL IMPACTS WILL NEED TO BE REFINED/RESOLVED WITH FUTURE
MODEL RUNS AT SHORTER TIME INTERVALS. A STORM TRACK CLOSE THE
COAST WOULD FAVOR SNOWS OVER THE INTERIOR OF PA AND PERHAPS EVEN
AT LOWER ELEVATIONS. THE 03/12Z DETERMINISTIC ECMWF REMAINS THE
THE MOST BULLISH ON THIS SCENARIO.
GIVEN THE CONTINUATION OF THE BLOCKING PATTERN AND NEGATIVE
NAO...ALTHOUGH NOT QUITE AS PROMINENT AS LAST WEEK...PREFER TO LEAN
TOWARD THE ECMWF GUIDANCE...PARTICULARLY THE ENSEMBLE PRODUCTS...
WHICH HANDLED THE COMPLEX INTERACTION BTWN THE DIGGING H5 SYSTEM INTO
THE SERN STATES AND SANDY MUCH BETTER THAN THE OTHER GLOBAL MODEL
AND ENSEMBLE SYSTEMS ESPECIALLY IN THE MEDIUM RANGE/BEYOND 72HRS.
WHILE THE DETAILS REMAIN UNCLEAR...FELT THAT AN INCREASE IN POPS/QPF
WAS JUSTIFIED FOR DAYS 4-5 /WED-THUR/ OVER CENTRAL AND ERN SXNS WITH
THE POTENTIAL FOR ACCUMULATING SNOWS MAINLY OVER THE INTERIOR OF
CENTRAL PA. THERMAL PROFILES LOOK MARGINAL SO ELEVATION WOULD LKLY BE
A FACTOR. FOR NOW WILL SIMPLY MENTION RAIN OR SNOW PTYPES IN THE
GRIDS AND TEXT FORECAST UNTIL A CONSENSUS SOLUTION EMERGES.
OUTSIDE OF THE POTENTIAL HIGH-IMPACT WINTRY WEATHER FOR THE MID-WEEK
PERIOD...THE REMAINDER OF THE FCST LOOKS TRANQUIL AND DRY. HIGH PRES
SHOULD ENSURE FAIR/DRY CONDITIONS WITH BLW NORMAL TEMPS EARLY IN THE
WEEK /INCLUDING ELECTION DAY/ BEFORE RETREATING NEWD INTO NEW
ENGLAND. COLD AND BLUSTERY CONDS WOULD BE EXPECTED LATE NEXT WEEK
ON THE BACKSIDE OF THE DEEP LOW MOVG TWD SRN NEW ENGLAND. 500 HPA
HEIGHTS ARE FORECAST TO RISE ABOVE NORMAL INTO THE WEEKEND...SUPPORTING
A SIGNIFICANT MODERATION IN DAILY MAX/MIN TEMPS.
