Winter Storm in Maryland, January 3, 2002

AREA FORECAST DISCUSSION...PRELIMINARY...
NATIONAL WEATHER SERVICE WAKEFIELD, VA
420 AM EST WED JAN 2 2002

...WILL EXPAND WINTER STORM WARNING NORTH TO INCLUDE RICHMOND...
...OVER A FOOT OF SNOW LIKELY IN PTNS OF SE VA/NE NC AWAY FM COAST...

1006 LOW CENTER IS CURRENTLY 150-175 MILES EAST OF THE NC/SC
COAST...CLOSE TO ETA/AVN PROJECTIONS FROM THE 00Z RUN. 00Z ETA
SHOWED THE LOW A LITTLE FARTHER OFFSHORE BY THIS AFTN...HOWEVER
LATEST (06Z) RUC HAS THE LOW CENTER CLOSER TO THE COAST. 06Z
MESO-ETA IN LINE WITH THE 00Z ETA. BOTTOM LINE...BOTH AVN/ETA
CONTINUE IN GENERAL AGREEMENT...BUT AGAIN WITH THE 00Z RUNS DIFFER
WITH THE AMOUNT/EXTENT OF ACCUMULATED PRECIP. FORECAST CONCERNS
CONTINUE TO BE WITH PRECIP TYPES AND AMOUNTS WITH THIS SYSTEM...
ALONG WITH YET ANOTHER SYSTEM LOOMING LATE THIS WEEKEND.

TODAY...DEGREE OF 850-500 DEFORMATION WITH THIS SYSTEM IS QUITE
IMPRESSIVE...STRONGEST IN AN WSW-ENE AXIS FROM NE NC THROUGH SE VA.
DYNAMICALLY...DPVA/WARM ADVECTION FROM APPROACHING UPPER TROUGH IS
BEING ENHANCED BY THE MORE FRONTOGENETIC...RRQ JET FORCING FROM THE
NORTH. QC CHARTS SHOW BOTH QS/QN CONVERGENCE MAX JUST TO THE SOUTH
ACROSS MUCH OF NC. DURING THE AFTERNOON...WWA/ISENTOPIC LIFT
MECHANISM WILL SHIFT E WITH THE BACK-SIDE MID LEVEL DEFORMATION AXIS/
COLD CONVEYOR BELT HANGING BACK AND KEEPING THE SNOWS GOING.

MAX LIQUID QPF PER ETA IS BTWN 1 AND 1.5 IN A SWATH FROM NORTHAMPTON
CO NORTH CAROLINA TO NORFOLK. AVN BULLSEYE IS CLOSER TO 1.
MOISTURE/QPF GRADIENT PER ETA IS TIGHTER N-S THAN THAT OF THE
AVN...WHICH MAKES SINCE GIVEN THE DEGREE OF DEFORMATION WITH THIS
SYSTEM. AVN ACTUALLY HAS A QUARTER INCH OF LIQUID UP THROUGH
CAROLINE COUNTY...WHILE ETA IS FARTHER S TOWARD RICHMOND AND MD/VA
BORDER ON THE EASTERN SHORE. WILL CONTINUE TO SIDE WITH THE ETA IN
TERMS OF PINPOINTING HOW FAR NORTH THE ACCUMULATING SNOWS WILL GET.

IN TERMS OF AMOUNTS...CURRENT REPORTS SHOW 4-7 OVER MUCH OF SE VA
AND NE NORTH CAROLINA AWAY FROM THE COAST. GARCIA TECHNIQUE SHOWS
UPWARDS TO 10-14 IN A 18 HOUR PERIOD WHERE THE HEAVIEST SNOW IS
EXPECTED TO OCCUR. THIS IS BASED ON MIXING RATIOS TOPPING OUT BTWN
3-4 G/KG THROUGH EARLY AFTN. HOWEVER...GIVEN THAT MOST AREAS WILL
PROBABLY SEE GREATER THAN 18HRS OF ACCUMULATING SNOW...THINK SOME
AREAS MAY EXCEED THESE TOTALS. HAVE ALSO EXTENDED THE WARNING NORTH
TO INCLUDE METRO RICHMOND AND FARMVILLE. EVEN THE ETA...WITH THE
TIGHTER N-S GRADIENT OF PRECIP...HAS BETWEEN A QUARTER AND A HALF
INCH TOTAL QPF REACHING THIS AREA. A SPOTTER IN RICHMOND IN FACT
ALREADY REPORTED 3 RECENTLY.

CONTINUED ACCUMULATING SNOWS INTO THE EVENING NEAR THE COAST...AS
COLD AIR BEGINS TO WRAP AROUND THE SYSTEM AND CHANGES ANY RAIN/MIXED
PRECIP BACK OVER TO SNOW. AM CONCERNED ABOUT THE POTENTIAL FOR HEAVY
SNOW LINGERING THIS EVENING...ESP NEAR THE OUTER BANKS. ETA QPF
SHOWS ANOTHER QUARTER TO HALF INCH OF LIQUID BTWN 0 AND 6Z...WHEN
THE PRECIP WILL HAVE CHANGED OVER TO ALL SNOW AS A RESULT WILL ALSO
EXPAND THE WINTER STORM WARNING TO INCLUDE THE OUTER BANKS OF
CURRITUCK CO...FOR NOW HITTING ON ACCUMS UP TO 4 ALONG THE COAST.

NOT MUCH CHANGE TO THE EXTENDED...THOUGH THE NEXT STORM (SUN
NIGHT/MON) WILL NO DOUBT BEAR WATCHING. LATEST AVN DOES NOT PHASE
THE NRN/SRN STREAM UPPER TROUGHS AS FAST COMPARED TO THE PREVIOUS
RUN...WITH THE NRN STREAM TROUGH FARTHER SOUTH AND (THUS) ALSO THE
SFC LOW (OF THE NC/SC COAST). THIS SCENARIO WOULD SUGGEST MORE OF A
SNOW EVENT VS. RAIN OR A MIX ACROSS MUCH OF THE FCST AREA...STAY
TUNED.

ADDITIVE DATA WILL FOLLOW...INCLUDING WARNING/ADVISORY INFO. EXPECT
THE ZONES/STATEMENTS SOON..

HURLEY