-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 280840
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
440 AM EDT MON JUL 28 2014

.SYNOPSIS...
-- Changed Discussion --
A COLD FRONT WILL PASS ACROSS THE REGION THIS MORNING...BRINGING A
SHOT OF COOLER DRIER CANADIAN AIR TO THE MID ATLANTIC. AN UPPER
LEVEL DISTURBANCE PASSING ACROSS THE GREAT LAKES WILL BRING GUSTY
WINDS TO THE FORECAST REGION LATE THIS MORNING AND THIS
AFTERNOON...IN ADDITION TO SPOTTY UPSLOPE SHOWERS ALONG THE
WESTERN RIDGES. COOLER CONDITIONS WILL REMAIN ACROSS THE AREA
THROUGH MUCH OF THE WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 400 AM EDT MONDAY...

ASIDE FROM A FEW SPRINKLES LEFT OVER ACROSS THE MOUNTAINS THIS
MORNING...ALL SHOWER ACTIVITY HAS EXITED THE AREA FOR THE TIME
BEING. THE COLD FRONT CONTINUES TO MAKE STEADY PROGRESS ACROSS
WEST VIRGINIA AS THE PARENT SURFACE LOW SHIFTS EAST OVER EASTERN
PENNSYLVANIA...AND EXPECT THE COLD FRONT TO ENTER OUR SOUTHEAST
WEST VIRGINIA COUNTIES BY AROUND SUNRISE...PUSHING RAPIDLY EAST
THROUGH THE MORNING.

THE MAIN CONCERN FOR THE MORNING WILL BE GUSTY WINDS ACROSS THE
MOUNTAINS BEHIND THE FRONT AS A DEEP UPPER LEVEL DISTURBANCE
PASSES ACROSS THE EASTERN GREAT LAKES. STRONG WINDS WRAPPING
AROUND THE SOUTHERN END OF THE DISTURBANCE WILL PUSH ACROSS THE
MOUNTAINS DURING LATE MORNING AND EARLY AFTERNOON...AND EXPECT
GUSTS TO MAX OUT AS HIGH AS 40 MPH AT TIMES AT ELEVATIONS OF 30OO
FEET AND UP. THE MAIN ENERGY MOVING AROUND THE UPPER DISTURBANCE
WILL SHIFT EAST OF THE AREA DURING MID AFTERNOON...AND EXPECT TO
SEE WIND SPEEDS GRADUALLY DIMINISH THEREAFTER.

WITH WINDS SHIFTING NORTHWESTERLY AROUND THE BACKSIDE OF THE
DISTURBANCE DURING EARLY AFTERNOON...WILL ALSO SEE SPOTTY UPSLOPE
SHOWER ACTIVITY DEVELOP ACROSS OUR WESTERN RIDGELINES OF SOUTHEAST
WEST VIRGINIA INTO THE NORTH CAROLINA MOUNTAINS. LAPSE RATES WILL
BECOME STEEP ENOUGH FOR A FEW HOURS DURING THE AFTERNOON THAT
WOULD NOT BE SURPRISED TO SEE A FEW SHOWERS DEVELOP INTO
THUNDERSTORMS...BUT BELIEVE THOSE WILL BE FEW AND FAR IN BETWEEN
AT BEST. SHOWER ACTIVITY WILL DECREASE INTO THE EVENING AS WIND
SPEEDS CONTINUE TO DIMINISH...BUT EXPECT A FEW SHOWERS TO LINGER
INTO EARLY TUESDAY.

TEMPERATURES WILL BE COOLER ACROSS THE MOUNTAINS TODAY ONCE THE
FRONT PASSES...HOWEVER THERE WILL BE TIME FOR DECENT HEATING
BEFORE THE FRONT ARRIVES ACROSS THE PIEDMONT CONSIDERING THE
DECREASING CLOUD COVER AND DRY DOWNSLOPE WESTERLY WINDS. EXPECT
HIGHS TO RANGE FROM THE LOW 70S ACROSS THE WESTERN RIDGES TO THE
UPPER 80S ACROSS THE SOUTHSIDE. LOWS TONIGHT WILL FALL INTO THE
LOW 50S WEST AND THE LOW 60S EAST.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
-- Changed Discussion --
AS OF 230 AM EDT MONDAY...

MODELS ARE IN GOOD AGREEMENT THAT A FULL LATITUDE UPPER TROF WILL
COVER THE EASTERN HALF OF THE U.S. DURING THE SHORT TERM
PERIOD...KEEPING TEMPERATURES WELL BELOW AVERAGE FOR LATE JULY.

WITH ONLY A THIN LAYER OF MOISTURE EXPECTED BETWEEN 5-10KT
TUESDAY...PRECIPITATION WILL BE HARD TO COME BY...BUT KEPT A SMALL
CHANCE IN FAR SOUTHWEST VA AND NW NC...AS A WEAK UPPER LEVEL
IMPULSE ROUNDS THE BASE OF THE UPPER TROF. OTHERWISE...ONLY SOME
CUMULUS CLOUDS WILL COVER THE REGION. TUESDAY SHOULD BE THE
COOLEST DAY DURING THIS PERIOD WITH THE GEFS FORECASTING 850MB
TEMPS 2-3 STANDARD DEVIATIONS BELOW NORMAL. MODEL GUIDANCE HAS
BEEN VERY CONSISTENT FROM RUN TO RUN WITH ITS HIGH TEMPERATURE
FORECAST....SO STRAYED LITTLE FROM THE UPPER 60S/LOWER 70S
FORECAST IN THE MOUNTAINS TO UPPER 70S/LOWER 80S EAST OF THE BLUE
RIDGE.

A WEAK LOW THAT FORMS OFF THE CAROLINA COAST TUESDAY LIFTS NORTHEAST
INTO THE ATLANTIC SHOULD REMAIN FAR ENOUGH EAST TO NOT INFLUENCE OUR
WEATHER. SFC HIGH PRESSURE BUILDS INTO THE WESTERN PORTION OF THE
FORECAST AREA BY 12Z (8 AM EDT) WEDNESDAY. GOOD RADIATIONAL COOLING
CONDITIONS SHOULD ALLOW LOW TEMPS TO FALL INTO THE 40S IN SOME
LOCATIONS IN THE MOUNTAINS TO THE MID TO UPPER 50S IN THE EAST.
THESE VALUES WILL BE CLOSE TO THE RECORDS FOR JULY 30TH. SEE CLIMATE
SECTION BELOW FOR RECORD LOWS FOR WEDNESDAY.

UPPER TROF RELAXES SOME ON WEDNESDAY...ALLOWING 850MB TEMPS TO WARM
A COUPLE OF DEGREES VERSUS TUESDAY. STILL...TEMPS WILL BE WELL BELOW
NORMAL. THE 00Z NAM AND 21Z SREF APPEAR BULLISH ON DEVELOPING
UPSLOPE SHOWERS WEDNESDAY AFTERNOON. CONSIDERING THE AMOUNT OF DRY
AIR IN PLACE...KEPT THE FORECAST DRY. SFC HIGH PRESSURE FORECAST TO
SIT OVER THE WESTERN HALF OF THE FORECAST AREA WEDNESDAY
NIGHT...BUT WITH DEW POINTS SLIGHTLY HIGHER...LOWS WILL BE A
DEGREE OR TWO WARMER THURSDAY MORNING...BUT STILL WELL BELOW
NORMAL AND CLOSE TO RECORD LOWS IN SOME LOCATIONS LIKE LWB.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 1200 PM EDT SUNDAY...

A SURFACE HIGH THURSDAY OVER SOUTHERN MICHIGAN WILL SHIFT EAST
TOWARDS NEW ENGLAND BY FRIDAY AND SATURDAY. AT THE MID LEVELS A
PERSISTENT TROUGH IS SET UP OVER THE EASTERN US WITH A RIDGE OVER
THE WESTERN US. THURSDAY LACKS LOW AND MID LEVEL MOISTURE SO EXPECT
THE DAY TO BE DRY. MOISTURE AND INSTABILITY INCREASE FOR FRIDAY AND
THROUGH THE REST OF THE PERIOD AS SEVERAL DISTURBANCES PIVOT ACROSS
THE REGION AROUND THE BASE OF THE TROUGH. EXPECT SCATTERED SHOWERS
AND THUNDERSTORMS TO DEVELOP EACH AFTERNOON/EVENING AND TAPER OFF TO
JUST SCATTERED SHOWERS DURING THE EVENING. FOCUS OF THE HIGHEST
CHANCE POPS ARE OVER THE MOUNTAINS WHERE THE BEST CONVERGENCE WILL
BE LOCATED...WITH LOWER CHANCE POPS OUT EAST.

THURSDAY WILL BE THE WARMEST DAY OF THE PERIOD WITH 850MB TEMPS
AROUND +16C. THIS WILL CORRESPOND TO SURFACE HIGH TEMPS IN THE MID
80S OUT EAST AND NEAR 80 ACROSS THE MOUNTAINS. AS THE HIGH SHIFTS
EAST ON FRIDAY THE WINDS WILL SHIFT FROM N/NW TO AN EASTERLY
DIRECTION. THIS WILL WEDGE THE AREA IN THROUGH THE REMAINDER OF THE
PERIOD. WITH THE INCREASED LOW/MID LEVEL MOISTURE EXPECT CLOUDY
CONDITIONS. THIS ALONG WITH EXPECTED SCATTERED PRECIP AND 850MB
TEMPS FALLING TO +11-14C...SURFACE HIGH TEMPS WILL BE 5-10 DEGREES
BELOW NORMAL FRIDAY THROUGH SUNDAY.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AS OF 150 AM EDT MONDAY...

KEEPING AN EYE ON THE LAST OF THE CONVECTION ENTERING THE MOUNTAIN
EMPIRE THIS MORNING...BREAKING UP AS IT BEGINS TO MOVE DOWNSLOPE
EAST OF THE HIGHEST RIDGES. MAY SEE BRIEF GUSTY WINDS AT BLF AS
SHOWERS PASS...DRAWING STRONGER WINDS ALOFT TO THE SURFACE.
SHOWERS WILL EXIT BY 08Z...AND EXPECT ONLY ISOLATED DEVELOPMENT
THEREAFTER ALONG THE WESTERN RIDGES.

THE COLD FRONT IS MAKING ITS WAY ACROSS WV AND WILL ENTER THE
VICINITY OF KLWB/KBLF BY AROUND 09Z...AND PROGRESS EAST QUICKLY
THROUGH THE MORNING. WESTERLY DOWNSLOPE WINDS WILL MAINTAIN VFR
CONDITIONS FOR KROA/KLYH/KDAN EAST OF THE BLUE RIDGE WHILE
LINGERING STRATOCU WILL RESULT IN PATCHY MVFR CEILINGS FOR A FEW
HOURS BEFORE SUNRISE FOR KBCB/KLWB/KBLF.

THROUGH THE DAY...ENERGY ROTATING THROUGH THE UPPER TROF WILL
COMBINE WITH UPSLOPE AND INSTABILITY BELOW THE SUBSIDENCE
INVERSION AND STEEPISH LAPSE RATES AS SEEN ON MODEL SOUNDINGS TO
SQUEEZE OUT A FEW SPRINKLES AT KLWB AND KBLF BY LATE AFTERNOON.
WINDS LOOK TO BE GUSTY THROUGH THE FIRST PART OF THE TAF AS 850MB
FLOW IS ZIPPING ALONG AND DOWNWARD MOMENTUM TRANSFER SHOULD BE
EFFICIENT TO MIX IT DOWN AFTER DAYBREAK. THE LATTER PORTION OF THE
TAF PERIOD LOOKS QUIET WITH VFR EAST OF THE RIDGE AND MVFR WEST
AND WINDS SETTLE DOWN TOWARD EVENING BEFORE DECOUPLING.

EXTENDED AVIATION DISCUSSION...
DRIER AIR PUSHING IN FOR TUESDAY-WEDNESDAY WILL BRING MAINLY VFR
CONDITIONS...BUT CANNOT RULE OUT LATE NIGHT FOG AT KBCB/KLWB...
ALTHOUGH THE LOW LEVELS MAY STAY DRY ENOUGH FOR LESS FOG COVERAGE.

VARIABLE CIGS EXPECTED UNDER ANOMALOUS UPPER LOW THROUGHOUT THE
REST OF THE WEEK. A FEW -SHRA NOT COMPLETELY OUT OF THE QUESTION
ACROSS EASTERN WV...ALONG WITH OCCASIONAL MVFR CIGS. TYPICAL FOG
POTENTIAL LESS THAN NORMAL FOR THIS TIME OF YEAR THROUGHOUT THE
WEEK BECAUSE OF TURBULENT MIXING AND PREVAILING CYCLONIC FLOW.
TOWARD THE END OF THE WEEK...AS THE UPPER LOW RETROGRADES JUST
WEST OF THE REGION...INCREASING POTENTIAL FOR SHRA/TSRA BUT MAINLY
SW OF THE TAF SITES INTO FRIDAY.

&&

.CLIMATE...

-- Changed Discussion --
JULY 30TH RECORD LOWS:

ROANOKE......54...1997
BLUEFIELD....50...1981
DANVILLE.....60...1972/81/83/2013
LEWISBURG....46...2013
LYNCHBURG....52...1997
BLACKSBURG...50...1973/81


JULY 31ST RECORD LOWS:

ROANOKE......49...1914
BLUEFIELD....49...1997
DANVILLE.....55...1966
LEWISBURG....48...1997
LYNCHBURG....49...1997
BLACKSBURG...44...1997
-- End Changed Discussion --

&&

.EQUIPMENT...
THE WEATHER RADIO AT HINTON WEST VA TRANSMITTING ON FREQUENCY
162.425 MHZ REMAINS OFF THE AIR LIKELY DUE TO PHONE LINE PROBLEMS.
RESTORATION OF SERVICE IS NOT EXPECTED BEFORE NOON ON MONDAY.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...NF
NEAR TERM...NF
SHORT TERM...PH
LONG TERM...CF
AVIATION...MBS/NF
CLIMATE...PH
EQUIPMENT...JH