Area Forecast Discussion
Issued by NWS Blacksburg, VA

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000
FXUS61 KRNK 260459
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
1159 PM EST SUN JAN 25 2015

.SYNOPSIS...
LOW PRESSURE OVER KENTUCKY WILL MOVE EAST TONIGHT AND ACROSS THE
CENTRAL APPALACHIANS ON MONDAY. THIS SYSTEM WILL BRING PERIODS OF
SNOW AND RAIN TO MUCH OF THE REGION LATE TONIGHT INTO MONDAY.
STRONG NORTHWEST FLOW SHOULD FOLLOW THIS FEATURE MONDAY NIGHT INTO
TUESDAY BEFORE HIGH PRESSURE BUILDS IN FOR THE MIDDLE OF THE WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
AS OF 955 PM EST SUNDAY...

MSAS ANALYSIS HAD THE SURFACE LOW IN CENTRAL KENTUCKY AT 9PM/02Z.
CLOUD BASES WERE LOWERING AND THE AIR MASS WAS GRADUALLY
SATURATING BUT ONLY PRECIPITATION WAS IN THE FAR SOUTHWEST COUNTY
WARNING AREA UP TO THIS POINT. HAVE ADJUSTED THE TIMING FOR THE
ARRIVAL OF THE RAIN UNTIL AFTER 05Z/MIDNIGHT BASED ON CURRENT
RADAR TRENDS AND THE LATEST BUFKIT SOUNDINGS. ALSO ADJUSTED
MINIMUMTEMPERATURES UP A FEW DEGREES. DO NOT EXPECT MOST
LOCATIONS TO DROP INTO THE LOWER 30S UNTIL AROUND 6AM/11Z.

AS THIS COLD POOL BEGINS TO CROSS THE MOUNTAINS TOWARD MONDAY
MORNING...MODELS SUGGEST AN ENHANCED AREA OF LIFT IN THE WARM
ADVECTION/DIFFLUENT AXIS JUST EAST OF THE SURFACE LOW WHEN ENERGY
TRANSFER BEGINS TO TAKE SHAPE. THIS POSSIBLE AREA OF HEAVIER
PRECIP OF CONCERN IN CAUSING ADDED COLUMN/BOUNDARY LAYER COOLING
WHICH COULD LEAD TO A FEW HOURS OF SNOW ESPCLY GREENBRIER EAST
ACROSS THE HIGHLANDS INTO THE SOUTHERN SHENANDOAH VALLEY LATE.
SINCE CONSENSUS OF MOST GUIDANCE SHOWS THIS AND HAVE TRENDED
COLDER...UPPING AMOUNTS FOR QUICK BURST OF WET SNOW BY DAYBREAK
MONDAY BUT TRICKY AS IF PRECIP IS LIGHTER THEN MAY ONLY BE RAIN
OUTSIDE THE HIGHEST ELEVATIONS. SINCE CORRIDOR LOOKS TO FOCUS
ALONG THE I-64 CORRIDOR AND RIGHT AROUND RUSH HOUR...PLAN TO HOIST
A WINTER WEATHER ADVISORY FOR A FEW COUNTIES ACROSS THE NORTH
OVERNIGHT INTO MIDDAY MONDAY FOR 1-4 INCHES OF WET SNOW. IF THINGS
ORGANIZE MORE THEN COULD SEE HEADLINES NEEDED FARTHER SOUTH INTO
CRAIG/BOTETOURT CTYS AND EAST TO AMHERST BUT TOO IFFY TO INCLUDE
FOR NOW.

ELSEWHERE...EXPECTING PERHAPS A MIX TO SNOW AT TIMES SOUTH INTO THE
ROANOKE/NEW RIVER VALLEYS AND POINTS WEST AFTER MIDNIGHT BUT WITH MUCH
LESS ACCUMULATION AT THIS POINT. MAY SEE AN INCH OR TWO NW NORTH
CAROLINA MOUNTAINS BUT STAYING BELOW ADVISORY LEVELS THERE. OTHERWISE
SHOULD BE MOSTLY RAIN FROM LYH TO BEDFORD TO MTV TO UKF AND POINTS EAST
THROUGH MORNING. HIGHEST CATEGORICAL POPS MAINLY ALONG/NORTH OF HIGHWAY
460 WITH LIKELYS CENTRAL SECTIONS AND OVERALL CHANCE COVERAGE SOUTH.
LOWS MOSTLY IN THE 30S EXCEPT CLOSER TO 30 HIGHER ELEVATIONS OVER THE
NORTH AND POSSIBLY STAYING AROUND 40 SOUTH WHERE CLOUDS MAY TEND TO
LOCK IN WARMTH FROM THIS AFTERNOON.

COASTAL LOW QUICKLY DEEPENS AND TAKES MUCH OF THE DEEPER MOISTURE
NORTH/EAST BY MIDDAY MONDAY WITH A QUICK PUNCH OF COLD ADVECTION
WRAPPING INTO THE WEST DURING THE AFTERNOON. GUIDANCE AGAIN SUGGESTING
THAT DURING THIS TRANSITION THAT RAIN/SNOW MAY STILL LINGER OVER THE
WEST UNDER THE PASSAGE OF THE 5H LOW DURING THE MORNING. THIS WOULD BE
ENOUGH ESPCLY GIVEN COOLING ALOFT OVERTOP THE ONSET OF LOW LEVEL COLD
ADVECTION TO PRODUCE ADDED SNOWFALL OVER THE NW BEFORE AFTERNOON DRYING
OCCURS AND SOME DEGREE OF UPSLOPE KICKS IN. HOWEVER STILL APPEARS MAY
BE ENOUGH MOISTURE EVEN IN THE EAST UNDER THE PHASING SYSTEM TO PRODUCE
CONTINUED SPOTTY -RA SO ALTHOUGH EXPECT POPS TO STEADILY DECREASE BY
AFTERNOON...LEAVING IN SOME LINGERING CHANCE COVERAGE WITH LOW LIKELYS
FAR WESTERN SLOPES. SURGE OF COLD AIR ALONG WITH DECENT PRESSURE RISES
SUGGESTS INCREASING NW WINDS DURING THE AFTERNOON WITH SPEEDS PERHAPS
JUST BELOW ADVISORY NW NORTH CAROLINA MOUNTAINS AND QUITE BLUSTERY
ELSEWHERE. KEPT HIGHS MOSTLY IN THE 30S NW TO 40-45 BLUE RIDGE AND
UPPER 40S SE PENDING THE DEGREE OF CLOUDS/PRECIP MONDAY AFTERNOON.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 200 PM EST SUNDAY...

MONDAY NIGHT THROUGH TUESDAY...THE AXIS OF THE UPPER TROUGH WILL
CONTINUE TO SHIFT EAST OF THE REGION WITH NORTHWEST FLOW CONTINUING
ACROSS THE AREA. EMBEDDED WITHIN THAT FLOW WILL BE RESIDUAL MOISTURE
WITH AT LEAST LAKE ERIE ORIGINS...AND PERHAPS LAKE MICHIGAN. EXPECT
TO SEE A UPSLOPE SNOW SHOWERS ACROSS THE PREFERRED AREAS OF
SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH
CAROLINA. ADDITIONAL SNOWFALL TOTALS WILL BE GREATEST ACROSS WESTERN
GREENBRIER COUNTY WHERE TWO TO THREE MORE INCHES ARE POSSIBLE.
ELSEWHERE...WHERE MEASURABLE SNOW OCCURS...AMOUNTS WILL BE GENERALLY
BE LESS THAN AN INCH. RESIDUAL ISOLATED...LIGHT SNOW SHOWERS WILL
CONTINUE ACROSS WESTERN GREENBRIER COUNTY THROUGH TUESDAY EVENING
WITH LITTLE ADDITIONAL ACCUMULATION. ACROSS THE FAR NORTHEAST AND
EASTERN PORTIONS OF THE AREA...RESIDUAL LIGHT SNOW WILL BE POSSIBLE
MONDAY NIGHT ON THE BACKSIDE OF THE DEPARTING UPPER TROUGH. NO
MEASURABLE SNOWFALL IS EXPECTED. THE AFOREMENTIONED NORTHWEST WINDS
WILL BE ON THE GUSTY SIDE. THE HIGHER ELEVATIONS WILL EXPERIENCE
GUSTS IN THE 30 TO 40 MPH RANGE MONDAY NIGHT WITH SLIGHTLY SLOWER
GUSTS THROUGHOUT THE DAY TUESDAY.

LATE TUESDAY NIGHT THROUGH WEDNESDAY...SURFACE HIGH PRESSURE BUILDS
INTO THE AREA. THE CENTER OF THE HIGH SHIFTS TO THE EAST WEDNESDAY
NIGHT AND ALLOWS SURFACE WINDS TO TURN SOUTHWEST. NO PRECIPITATION
IS FORECAST...BUT CLOUDS WILL BE ON THE INCREASE WEDNESDAY NIGHT IN
ADVANCE OUR NEXT GREAT LAKES CLIPPER SYSTEM.

TEMPERATURES DURING THIS PORTION OF THE FORECAST PERIOD WILL TREND
FROM BEING A LITTLE BELOW NORMAL TO NEAR OR SLIGHT ABOVE NORMAL.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 230 PM EST SATURDAY...

UPPER LEVEL PATTERN WILL BE GOING BACK TO SPLIT FLOW FOR THE
EXTENDED WITH A CUTOFF LOW OVER THE BAJA PENINSULA DOMINATING THE
SOUTHERN STREAM...AND A WESTERN RIDGE/EASTERN TROF FOR THE NORTHERN
STREAM. GFS IS LESS AMPLIFIED WITH THE NORTHERN STREAM WHICH GIVES
IT A WARMER LOOK THAN THE ECMWF.

WE WILL SEE A NORTHERN STREAM LOW MOVE BY TO OUR NORTH ON THURSDAY
WHICH WILL BRING US A CHANCE OF LIGHT SYNOPTIC PRECIPITATION WHICH
LOOKS TO BE MIX TO RAIN FOR THURSDAY. THIS SYSTEM WILL THEN SWING A
COLD FRONT THROUGH THE REGION THURSDAY EVENING WHICH SETS THE STAGE
FOR UPSLOPE SNOW SHOWERS THURSDAY NIGHT INTO FRIDAY. THE WINDS
BEHIND THE COLD FRONT LOOK QUITE BLUSTERY RIGHT THROUGH FRIDAY.

HIGH PRESSURE THEN BUILDS OVER THE MID ATLANTIC REGION AND FORMS A
BIT OF A WEDGE WITH QUIET WEATHER FOR FOR SATURDAY. EURO WANTS TO
BRING A SURGE OF ARCTIC AIR INTO THE REGION AS WE HEAD INTO SUNDAY.
GFS IS NOT ON BOARD WITH THIS AND ENSEMBLES WERE NOT INDICATING A
MAJOR ARCTIC OUTBREAK. WILL BE LEANING MORE TOWARD THE GFS/ENSEMBLE
SOLUTION AND KEEP TEMPS SUNDAY INTO SUNDAY NIGHT A GOOD 20F WARMER
THAN THE ECMWF.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 1155 PM EST SUNDAY...

CEILINGS WERE VFR BUT LOWERING OVER THE FORECAST AREA TONIGHT.
CEILINGS WILL QUICKLY LOWER TO IFR AS THE RAIN ARRIVES FROM WEST
TO EAST BETWEEN 09Z/4AM AND 11/6AM. THERE MAY BE SNOW MIXED IN THE
WITH RAIN AT KBLF AND KLWB FOR A COUPLE HOURS IN THE MORNING BUT
CONFIDENCE IS LOW.

LOW PRESSURE WILL MOVE FROM KENTUCKY DIRECTLY ACROSS SOUTHERN
VIRGINIA. AS THE LOW PROGRESSES OFFSHORE AND WINDS COME AROUND TO
THE WEST AND NORTHWEST...MUCH COLDER AIR COMES INTO THE REGION.
RAIN WILL CHANGE TO SNOW IN THE MOUNTAINS AFTER 21Z/4PM. LIGHT
ACCUMULATIONS ARE EXPECTED AT KLWB. HIGH CONFIDENCE THAT WINDS
WILL BECOME GUSTY AFTER 00Z AT ALL TAF SITES AS THE LOW DEEPENS
OFFSHORE.

EXPECT CEILINGS TO COME UP A BIT MONDAY AFTERNOON EAST OF THE BLUE
RIDGE...BUT REMAIN BORDERLINE IFR/MVFR IN THE FAVORED UPSLOPE
AREAS THROUGH MONDAY NIGHT.

EXTENDED DISCUSSION...NORTHWEST FLOW CONTINUES ON TUESDAY. MVFR
CONDITIONS LIKELY ACROSS BLF/LWB AND PERHAPS EVEN BCB DUE TO
SCATTERED UPSLOPE SNOW SHOWERS. EASTERN TAF LOCATIONS SHOULD
REMAIN VFR ON TUESDAY. HIGH PRESSURE ON WEDNESDAY WILL PROVIDE A
QUIET DAY WITH VFR CONDITIONS ACROSS ALL TAF LOCATIONS. ANOTHER
CLIPPER SYSTEM ARRIVES ON THURSDAY...BRINGING A CHANCE OF SUB-VFR
CEILINGS AND VSBYS.

&&

.EQUIPMENT...
HINTON ALL HAZARDS RADIO...162.425MHZ IS OFF THE AIR. THERE IS NO
ESTIMATE FOR RETURN TO SERVICE.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR VAZ019-020-
     024.
NC...NONE.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST MONDAY FOR WVZ507-508.

&&

$$
SYNOPSIS...JH
NEAR TERM...AMS/JH
SHORT TERM...DS
LONG TERM...MBS
AVIATION...AMS/CF
EQUIPMENT...AMS



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