Post by Ritty77 on Jan 23, 2011 12:42:02 GMT -5
MAIN FOCUS IN THE LONG TERM IS STORM POTENTIAL IN THE EARLY TO
MIDDLE PORTION OF THE PERIOD...WITH MODELS AND ENSEMBLE PREDICTION
SYSTEMS CONTINUING TO DEVELOP A POTENTIALLY SIGNIFICANT EAST COAST
WINTER STORM FOR LATE TUESDAY THROUGH EARLY THURSDAY.
FOR NOW...THE TYPICAL UNCERTAINTIES WITH TIMING...TRACK AND
INTENSITY OF UPPER LEVEL AND BOUNDARY LAYER FEATURES ARE IN PLAY.
THE OPERATIONAL ECMWF HAD BEEN THE MOST CONSISTENT AND IMPRESSIVE
DURING THE PAST 36 TO 48 HOURS...DEPICTING WHAT COULD BEST BE
CHARACTERIZED AS A SUPERSTORM-TYPE SOLUTION THAT (IF VERIFIED)
WOULD PRODUCE WIDESPREAD HEAVY SNOWFALL OVER CENTRAL AND EASTERN
PENNSYLVANIA. WOO HOO! HOWEVER...SATURDAY ECMWF RUNS INDICATED A
SIGNIFICANT EASTWARD SHIFT TO WHAT HAD BEEN A CONSISTENT
SOLUTION...BOTH IN TERMS OF TRACK AND INTENSITY. D'OH. THIS IS TO BE
EXPECTED FOR THE MAJORITY OF ECWS SCENARIOS DAYS IN ADVANCE...AND
DOES NOT DIMINISH THE POTENTIAL PERSAY OF A LARGE WINTER STORM. IT
DOES HOWEVER UNDERSCORE THE IMPORTANCE OF EXPRESSING UNCERTAINTY
THIS FAR IN ADVANCE OF A POTENTIALLY LARGE STORM...AND TO FOCUS ON
COMMUNICATING THAT UNCERTAINTY ALONG WITH TRENDS.
WITH THAT BEING SAID...THE LATEST ROUND OF 00Z/23 JAN GUIDANCE IS
IN GOOD AGREEMENT IN DEVELOPING A SIGNIFICANT WINTER STORM ALONG
THE EASTERN SEABOARD LATE TUESDAY THROUGH THURSDAY. THE 00Z/23
OPERATIONAL ECMWF NOW TRACKS A STRONG SURFACE LOW SPLITTING THE
DIFFERENCE BETWEEN SATURDAY`S "WIDE RIGHT" SOLUTION WELL OFFSHORE
AND THU/FRI POTENTIALLY WORST CASE SCENARIO FOR CENTRAL
PA...PRODUCING A LIGHT TO MODERATE SNOWSTORM FOR PORTIONS OF
CENTRAL AND SOUTHEAST PENNSYLVANIA. THE 00Z/23 ECMWF SOLUTION
CLOSELY MIRRORS THE 00Z/23 GEFS ENSEMBLE MEAN MSL FIELDS IN TRACK
AND INTENSITY...WHICH STRENGTHENS CONFIDENCE IN AT LEAST MINOR TO
MODERATE IMPACTS FOR CENTRAL AND EASTERN PORTIONS OF CENTRAL PA.
GIVEN THE SOURCE REGION OF UPPER LEVEL FEATURES...SIMILAR TO THE
LAST FEW MAJOR EAST COAST WINTER STORMS OF THIS MONTH...THE
EVENTUAL SOLUTIONS WILL BE STRONGLY DEPENDENT UPON HOW STRONGLY
UPPER LEVEL WAVES DIG THROUGH THE PLAINS TODAY THROUGH MONDAY...
AND THE INTENSITY OF GULF COAST AND SOUTHEASTERN CONVECTION
PUNCHING UP AN OFFSHORE WESTERN ATLANTIC RIDGE. MODELS ARE
NOTORIOUSLY POOR IN HANDLING THE STRENGTH OF SUCH WAVES AS THEY
RIDE OVER WESTERN NORTH AMERICAN RIDGES...AND WITH A POSITIVE PNA
PATTERN I DO EXPECT A GENERAL WESTWARD ADJUSTMENT TO THE TRACK OF
DETERMINISTIC AND GEFS MEAN MSL SOLUTIONS OVER THE NEXT 24 TO 36
HOURS. THIS WILL LIKELY INTRODUCE SOME PRECIPITATION TYPE ISSUES
FOR PARTS OF MY AREA...NAMELY THE SOUTHEAST...AND WILL NEED TO BE
ADDRESSED ONCE A MORE CONFIDENT SOLUTION IS IN HAND. STAY TUNED.
MIDDLE PORTION OF THE PERIOD...WITH MODELS AND ENSEMBLE PREDICTION
SYSTEMS CONTINUING TO DEVELOP A POTENTIALLY SIGNIFICANT EAST COAST
WINTER STORM FOR LATE TUESDAY THROUGH EARLY THURSDAY.
FOR NOW...THE TYPICAL UNCERTAINTIES WITH TIMING...TRACK AND
INTENSITY OF UPPER LEVEL AND BOUNDARY LAYER FEATURES ARE IN PLAY.
THE OPERATIONAL ECMWF HAD BEEN THE MOST CONSISTENT AND IMPRESSIVE
DURING THE PAST 36 TO 48 HOURS...DEPICTING WHAT COULD BEST BE
CHARACTERIZED AS A SUPERSTORM-TYPE SOLUTION THAT (IF VERIFIED)
WOULD PRODUCE WIDESPREAD HEAVY SNOWFALL OVER CENTRAL AND EASTERN
PENNSYLVANIA. WOO HOO! HOWEVER...SATURDAY ECMWF RUNS INDICATED A
SIGNIFICANT EASTWARD SHIFT TO WHAT HAD BEEN A CONSISTENT
SOLUTION...BOTH IN TERMS OF TRACK AND INTENSITY. D'OH. THIS IS TO BE
EXPECTED FOR THE MAJORITY OF ECWS SCENARIOS DAYS IN ADVANCE...AND
DOES NOT DIMINISH THE POTENTIAL PERSAY OF A LARGE WINTER STORM. IT
DOES HOWEVER UNDERSCORE THE IMPORTANCE OF EXPRESSING UNCERTAINTY
THIS FAR IN ADVANCE OF A POTENTIALLY LARGE STORM...AND TO FOCUS ON
COMMUNICATING THAT UNCERTAINTY ALONG WITH TRENDS.
WITH THAT BEING SAID...THE LATEST ROUND OF 00Z/23 JAN GUIDANCE IS
IN GOOD AGREEMENT IN DEVELOPING A SIGNIFICANT WINTER STORM ALONG
THE EASTERN SEABOARD LATE TUESDAY THROUGH THURSDAY. THE 00Z/23
OPERATIONAL ECMWF NOW TRACKS A STRONG SURFACE LOW SPLITTING THE
DIFFERENCE BETWEEN SATURDAY`S "WIDE RIGHT" SOLUTION WELL OFFSHORE
AND THU/FRI POTENTIALLY WORST CASE SCENARIO FOR CENTRAL
PA...PRODUCING A LIGHT TO MODERATE SNOWSTORM FOR PORTIONS OF
CENTRAL AND SOUTHEAST PENNSYLVANIA. THE 00Z/23 ECMWF SOLUTION
CLOSELY MIRRORS THE 00Z/23 GEFS ENSEMBLE MEAN MSL FIELDS IN TRACK
AND INTENSITY...WHICH STRENGTHENS CONFIDENCE IN AT LEAST MINOR TO
MODERATE IMPACTS FOR CENTRAL AND EASTERN PORTIONS OF CENTRAL PA.
GIVEN THE SOURCE REGION OF UPPER LEVEL FEATURES...SIMILAR TO THE
LAST FEW MAJOR EAST COAST WINTER STORMS OF THIS MONTH...THE
EVENTUAL SOLUTIONS WILL BE STRONGLY DEPENDENT UPON HOW STRONGLY
UPPER LEVEL WAVES DIG THROUGH THE PLAINS TODAY THROUGH MONDAY...
AND THE INTENSITY OF GULF COAST AND SOUTHEASTERN CONVECTION
PUNCHING UP AN OFFSHORE WESTERN ATLANTIC RIDGE. MODELS ARE
NOTORIOUSLY POOR IN HANDLING THE STRENGTH OF SUCH WAVES AS THEY
RIDE OVER WESTERN NORTH AMERICAN RIDGES...AND WITH A POSITIVE PNA
PATTERN I DO EXPECT A GENERAL WESTWARD ADJUSTMENT TO THE TRACK OF
DETERMINISTIC AND GEFS MEAN MSL SOLUTIONS OVER THE NEXT 24 TO 36
HOURS. THIS WILL LIKELY INTRODUCE SOME PRECIPITATION TYPE ISSUES
FOR PARTS OF MY AREA...NAMELY THE SOUTHEAST...AND WILL NEED TO BE
ADDRESSED ONCE A MORE CONFIDENT SOLUTION IS IN HAND. STAY TUNED.