A quick moving storm system may provide some overnight snow, sleet and freezing rain in Metro Richmond. This appears to be a very low-impact storm in terms of accumulation. I’ll update any accumulations tomorrow afternoon. As of the time of this posting, a trace amount (0.01″) of freezing rain has accumulated.

NWS Forecast discussion:

000
FXUS61 KAKQ 140257
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
957 PM EST TUE JAN 13 2015

.SYNOPSIS…
HIGH PRESSURE SITS OVER NEW ENGLAND OVERNIGHT INTO WEDNESDAY…AS
LOW PRESSURE DEVELOPING OFF THE FLORIDA COAST THIS EVENING…TRACKS
NORTHEAST JUST OFF THE CAROLINA COAST ON WEDNESDAY. HIGH PRESSURE
RETURNS FOR THE REST OF THE WEEK…BRINGING A RETURN TO MORE DRY
AND SEASONAL CONDITIONS.

&&

.NEAR TERM /THROUGH WEDNESDAY NIGHT/…
LATE THIS EVENG…INITIAL WEAK SHRTWV/LIFT IN SW FLO ALOFT WAS
PRODUCING MAINLY -RA…WITH PATCHY -IP AND -ZR ACRS SE VA AND NE
NC. BUT…NEXT STRONGER SHRTWV/ENHANCED VERTICAL MOTION/PCPN AREA
STARTING TO DEVELOP OVR CNTRL/ERN NC…WILL LIFT NE INTO AND ACRS
THE REGION OVRNGT INTO MIDDAY WED. BASED ON LATEST OBS AND 00Z WAL
SOUNDING…HAVE ADDED SLEET TO THE VA ERN SHR COUNTIES FOR OVRNGT
INTO WED MORNG. ONLY MINOR CHANGES TO TEMPS.

PREVIOUS DISCUSSION:
FOCUS TURNS TO A LOW PRESSURE SYSTEM DEVELOPING OFF THE FL COAST
TONIGHT THAT TRACKS NE OFF THE CAROLINA COAST ON WED. THE
INTERACTION BTWN COLD/DRY AIR FROM THE HIGH AND AN INFLUX OF MORE
MOIST/WARM AIR FROM THE SE WILL SET THE STAGE FOR WINTRY
PRECIPITATION OVER THE AREA LATE TONIGHT THROUGH WED.

AFTER EVALUATING CURRENT WX FEATURES/OBS VS 12Z MODEL DATA…HAVE
DETERMINED THAT THE GFS IS THE MODEL OF CHOICE. THIS IS ALSO THE
PREFERRED MODEL OF CHOICE BY WPC AND IS REFLECTED IN THEIR QPF
ANALYSIS. 12Z GFS/ECMWF MODEL SOLUTIONS KEEP A JET STREAK ACROSS THE
DEEP SOUTH TONIGHT…SHIFTING SLIGHTLY NWD ACROSS THE CAROLINAS ON
WED. WITH THE JET STAYING FARTHER SOUTH…THE REMNANT ARCTIC COLD
FRONT (CURRENTLY AROUND 150-250 MILES OFF THE CAROLINA COAST) IS
EXPECTED TO SLOWLY PUSH ESE TONIGHT THROUGH WED. THIS WILL KEEP
INCOMING PRECIPITATION CLOSER TO THE COASTAL AREAS (60-100 PERCENT
POPS) WITH LESSER CHANCES FARTHER INLAND (15-50 PERCENT POPS) AS THE
CENTRAL LOW PRESSURE CENTER STAYS WELL SOUTHEAST OF THE MID ATLANTIC
COAST. SOUNDING AND CROSS SECTION ANALYSES KEEPS AREAS WITHIN
CURRENT WINTER WX ADVISORY INTACT. FOR AREAS WITHIN THE CURRENT
WINTER WX ADVISORY…PRECIP WILL START AS ALL RAIN AND THEN
TRANSITION TO FREEZING RAIN OR A MIX OF FREEZING RAIN/SLEET AFTER
MIDNIGHT TONIGHT. THIS WINTRY MIX WILL PERSIST THROUGH WED MORNING
BEFORE TRANSITIONING BACK TO LIGHT SLEET (POSSIBLY MIXING WITH RAIN)
LATE WED MORNING INTO AFTN. THE MAIN IMPACT TIMING OF FREEZING RAIN
WILL BE FROM ROUGHLY 4-10 AM EARLY WED MORNING. LIGHT ICE
ACCUMULATIONS OF ONE TENTH OF AN INCH OR LESS ARE EXPECTED.
DANGEROUS TRAVEL CONDITIONS SHOULD BE ANTICIPATED LATE TONIGHT
THROUGH EARLY WED MORNING…ESPECIALLY ON UNTREATED ROADS AND
OVERPASSES. SEE WBCWSWAKQ FOR ADDITIONAL DETAILS AND UPDATES.

NORTHWEST OF THE WINTER WX ADVISORY AREA…A WINTRY MIX OF SNOW
AND SLEET IS EXPECTED AS LIQUID PRECIP OVERRUNS THE COLDER/DRIER
AIRMASS IN PLACE AT THE SFC. IT IS ANTICIPATED THAT MORE SLEET
THAN SNOW SHOULD FALL SINCE THERE IS NOT MUCH LIFT OR AMPLE
MOISTURE WITHIN THE DENDRITIC GROWTH ZONE TO SUPPORT ALL SNOW.
SNOW/SLEET ACCUMULATIONS WILL BE LIGHT…LESS THAN ONE HALF INCH
IN ANY 6 HOUR PERIOD AND LESS THAN ONE INCH OVERALL. A DEFORMATION
ZONE SETS UP OVER THE MD/VA EASTERN SHORE CENTERED ON 12Z…WHICH
MEANS THAT THERE COULD BE A QUICK BURST OF SNOW/SLEET BTWN 4-7 AM
ACROSS THE NRN NECK AND THE MD LOWER EASTERN SHORE. ANY
ACCUMULATIONS DURING THIS POSSIBLE BURST SHOULD STILL AMOUNT TO
ONE HALF INCH OR LESS.

AT THE COAST…PRECIPITATION WILL REMAIN AS ALL RAIN SINCE
TEMPERATURES AND DEWPOINTS WILL BE TOO WARM TO SUPPORT FROZEN
PRECIPITATION AT THE SFC. HOWEVER…WILL NEED TO KEEP A CLOSE EYE ON
DEWPOINTS FARTHER INLAND ACROSS THE SRN TIDEWATER AND NE NC AREAS
(AWAY FROM THE OCEAN AND ALBEMARLE SOUND). IF THEY DROP INTO THE MID
20S…THIS WILL CAUSE WET BULB TEMPERATURES TO FALL BELOW FREEZING
AND THEN FREEZING RAIN COULD BE POSSIBLE. CONFIDENCE IS NOT HIGH
ENOUGH AT THE TIME TO SUPPORT AN EXPANSION OF THE CURRENT WINTER WX
ADVISORY BUT IT IS WORTH NOTING WITHIN THIS FORECAST DISCUSSION.

FOR ALL AREAS…PRECIPITATION EXITS THE COAST LATE WED AFTN/EARLY
EVENING. WITH THE EXCEPTION OF COASTAL AREAS FROM THE VA EASTERN
SHORE TO THE TIDEWATER AREA TO COASTAL NE NC…PRECIP TYPE SHOULD
TRANSITION TO A MIX OF LIGHT SNOW/SLEET. THE AFOREMENTIONED COASTAL
AREAS WILL REMAIN AS ALL RAIN. A FEW LINGERING SHOWERS WILL BE
POSSIBLE OVER FAR SE COASTAL AREAS INTO THE EVENING AS THE SFC LOW
OFF THE CAROLINA COAST TRACKS FARTHER NE OUT TO SEA.

TEMPERATURES WILL BE A BIT TRICKY TONIGHT THROUGH WED NIGHT. TEMPS
SHOULD FALL NICELY ACROSS THE NORTH WHERE CLOUDS CLEARED DURING THE
DAY…BUT HOW FAR THEY DROP WILL BE DETERMINED BY THE INCOMING
CLOUDS FROM THE SW. LOWS WILL BE EVEN MORE TRICKY ACROSS THE SRN
HALF OF THE AREA WHERE PERSISTENT CLOUD COVER HAS HELD TEMPERATURES
STEADY WITH SLOW FALLS EARLY THIS EVENING. WINTER PRECIP POTENTIAL
WILL BE HIGHLY DEPENDENT ON SFC TEMPS AS WELL AS THE AFOREMENTIONED
DEWPOINTS. FOR NOW…LOWS ARE FORECAST IN THE LOW-MID 20S NORTH TO
UPPER 20S-LOWER 30S SOUTH (35-40 SE COAST). HIGHS WED WILL ALSO BE
TRICKY AS TEMPS SHOULD RISE SEVERAL DEGREES AFTER PRECIP COMES TO AN
END FROM WEST TO EAST WED AFTN. HIGHS WED GENERALLY IN THE MID-UPPER
30S (40-45 SE COAST). CLOUDS NOT EXPECTED TO CLEAR WED NIGHT AS HIGH
PRESSURE BUILDS ACROSS THE OHIO VALLEY…HOWEVER LIGHT NORTH WINDS
AND LINGERING EVAPORATIVE COOLING FROM RECENT PRECIP SHOULD RESULT
IN OVERNIGHT LOWS IN THE MID-UPPER 20S NW TO LOW-MID 30S SE.