• Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!

Pattern Fab Feb

Official guidance from GSP

KEY MESSAGE 2: A BRIEF RETURN OF WINTER WEATHER WITH VERY GUSTY NW
WINDS, ACCUMULATING SNOW FOR PORTIONS OF THE MOUNTAINS AND BELOW
NORMAL TEMPERATURES SUNDAY THROUGH TUESDAY.

NORTHWEST FLOW REALLY RAMPS UP ACROSS THE FORECAST AREA ON
SUNDAY, AS A COASTAL LOW RAPIDLY DEEPENS IN THE MID-ATLANTIC
COASTAL WATERS. A TIGHT PRESSURE GRADIENT AND STRONG LOW-LEVEL
CAA WILL SUPPORT VERY GUSTY WINDS ACROSS THE AREA BY EARLY AFTN
AND CONTINUING INTO SUNDAY NIGHT. PEAK GUSTS OF 30-40 MPH CANNOT
BE RULED OUT ACROSS MOST OF THE FOOTHILLS AND PIEDMONT SUNDAY
AFTN, BUT PEAK GUSTS INTO ADVISORY-CRITERIA RANGE OF 45-60 MPH
WILL BE POSSIBLE ABOVE 3500 FT HEADING INTO SUNDAY NIGHT. WITH
THE STRONGEST WINDS BEING IN LATE IN THE 2ND PERIOD AND INTO 3RD
PERIOD, WILL HOLD OFF ON ISSUING A WIND ADVISORY.

THERE MAY BE A BRIEF LULL IN SNOW SHOWER ACTIVITY IN THE MOUNTAINS
LATE SUNDAY MORNING THRU ABOUT MIDDAY, BUT MOISTURE SHOULD INCREASE
AGAIN IN THE AFTN AND RAMP UP SNOW SHOWERS ALONG THE TN BORDER. SNOW
ACCUMS WILL BE HIGHLY ELEVATION-DEPENDENT FOR THE FIRST FEW HOURS
OF THE EVENT DUE TO WARMER VALLEY TEMPS. THERE MAY ALSO BE A BAND
OF RAIN DEVELOPING WITHIN A DEFORMATION ZONE ASSOCIATED WITH THE
COASTAL LOW THAT COULD SET UP JUST EAST OF I-77. THIS IS NOT
EXPECTED TO BE HEAVY AND SHOULD BE ALL RAIN. OTHERWISE, SKIES
CLEAR OUT AND TEMPS RETURN TO BELOW-NORMAL FOR HIGHS, MAINLY IN
THE 30 TO LOWER 40S IN THE MOUNTAINS AND UPPER 40S TO LOWER 50S
IN THE PIEDMONT.

THE NORTHWEST FLOW SNOW MACHINE WILL BE CRANKING UP SUNDAY EVENING,
AS A STRONG MID-LEVEL SPEED MAX DIGS FROM THE CORN BELT SUNDAY
EVENING TO THE SOUTH CAROLINA COAST BY MONDAY MORNING. IN RESPONSE,
THE DEPTH OF POST-FRONTAL MOISTURE COVERING THE TN VALLEY AND MUCH
OF THE SOUTHERN APPALACHIANS WILL INCREASE TO NEAR 700 MB...WITH
TEMPS AT THE TOP OF THE MOIST LAYER COOLING TO -16 TO -20C. WHILE
THE DEPTH OF THE MOIST LAYER IS FORECAST TO BECOME GRADUALLY MORE
SHALLOW LATE SUNDAY NIGHT THROUGH MONDAY, TEMPS AT THE TOP OF THE
MOIST LAYER REMAIN NO WARMER THAN -16 UNTIL TUE EVENING. THIS MEANS
A PROTRACTED PERIOD...30 HOURS OR MORE OF A HIGH PROBABILITY OF
DENDRITIC ICE CRYSTAL GROWTH AND EFFICIENT SNOW:LIQUID RATIOS...ALL
WITHIN PERSISTENT STRONG NW UPSLOPE FLOW. SOLID WINTER WX ADVISORY
CRITERIA SNOWFALL IS LIKELY FROM THE HIGHER ELEVATIONS OF THE
SMOKIES NORTHEAST ACROSS THE MOUNTAINS AND VALLEYS OF THE OTHER NC
COUNTIES BORDERING TN. CURRENT FORECAST STORM TOTALS ARE GENERALLY
IN THE 1-4" RANGE IN THE VALLEYS NORTH OF I-40, WITH ABOUT TWICE
THAT RANGE EXPECTED ABOVE 3500 FEET. ESPECIALLY FAVORED UPSLOPE/HIGH
ELEVATION AREAS ALONG THE STATE LINE WILL LIKELY SEE AROUND A FOOT
OR MORE. THIS IS ENOUGH TO WARRANT ISSUANCE OF A WINTER STORM
WARNING FOR AVERY COUNTY AS WELL AS THE HIGH ELEVATIONS OF MITCHELL
COUNTY, WHILE WINTER WEATHER ADVISORIES WILL BE ISSUED FOR YANCEY,
MADISON, HAYWOOD, AND THE HIGH ELEVATIONS OF SWAIN.

WITH VERY WINDY (LIKELY WIND ADVISORY-LEVEL CONDITIONS OVER THE
MOUNTAINS) AND COLD ADVECTION CONTINUING INTO SUNDAY NIGHT,
WIDESPREAD WIND CHILL VALUES IN THE SINGLE DIGITS ARE EXPECTED
ACROSS THE MOUNTAINS, WITH SUB-ZERO READINGS LIKELY ABOVE 4000 FEET
OR SO. CURRENT INDICATIONS THAT THIS WILL BE "VERY CLOSE, BUT NOT
QUITE" IN TERMS OF REACHING COLD WEATHER ADVISORY CRITERIA, BUT
CAN'T RULE OUT THAT ONE WILL EVENTUALLY BE NEEDED FOR THE HIGHER
ELEVATIONS AND/OR THE NORTHERN NC MOUNTAINS. SNOW SHOWERS WILL
FINALLY STEADILY TAPER OFF MONDAY NIGHT, WITH DRY AND COOLER-THAN-
NORMAL CONDITIONS EXPECTED THROUGH TUESDAY. MOUNTAIN WIND CHILL
VALUES WILL AGAIN BE LOW MON NIGHT, BUT WITH WINDS STEADILY
DIMINISHING, THEY ARE EXPECTED TO BE A LITTLE HIGHER THAN ON SUNDAY
NIGHT.
 
You must log in or register to reply here.
Back
Top