Flash Flood Warning 41, NWS Blacksburg, VA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
225 AM EST FRI MAR 20 1998

MAIN FCST PRBLM OBVSLY CONVECTION TDY...HOW SOON WILL IT BE IN
CWA...HOW STRONG...AND WHERE THE STRONGEST.  KMRX 88D LOOP SHOWING
LINE OF STRONG TO SVR ECHOES...EMBEDDED BOWS...MVG INTO ERN TENN AND
AT CRNT RATE WOULD REACH NW NC MTNS PART OF RNK CWA BY ARND 6AM. 06Z
SFC ANAL STILL SHOWS A WRM FRNT SOMEWHERE IN VCNTY OF AVL AND THIS
WOULD HAVE TO MV NORTH BY 6AM TO ALLOW BETTER SFC INSBTY AND LOW LVL
SHEAR FOR SVR POTENTIAL.  THIS MAY NOT HAPPEN IN TIME FOR CRNT LINE
OF SVR CONV TO MAINTAIN ITS STRENGTH INTO OUR CWA...BUT NEW DVLPT
FURTHER SOUTH COULD REACH OUR CWA AT SVR LVLS AFT SUNRISE SOMTIME.
MDLS AGREE THAT BTWN 18 AND 00Z IS WHEN BEST COMBO OF THE BEST
PARAMETERS COME TOGETHER...DIV ALOFT/LOWLVL CON (ASSOC MAX UVV OVR
ROA AT 18Z ACRDG TO ETA TIME SECTION)...THETAE RDG...-2 TO -4 LIS AND
CAPES 500-1000.  SHEAR INCRSG DURING THE DAY WITH LOW LVL WNDS
BACKING TO SE...HODO PROFILE WILL HAVE SOME CLOCKWISE CURVATURE. ALL
ADDING UP TO GNRL AGRMNT WITH SPC OUTLOOK OF SLGT RSK FOR SRN HALF OF
CWA...BUT WOULD LEAN MORE TWD THE PDMT SECTIONS FOR BEST CHCS PARTLY
DUE TO TIMING...AFTERNOON HIER SFC TEMPS AND DWPTS. ON THE OTR
HAND...DRY SLOT FCST BY MDLS MAY BEGIN TO CUT OFF ATLC MSTR BY LATE
AFT SO OVRL MIDDAY MAY BE BEST CHC FOR ANY ISOLD SVR THREAT. WILL BE
ISSUING TSTRM OUTLOOK SPS LATER THIS MRNG.

WHILE PRE-FRONTAL CONV MAY LOOK A LTL AHEAD OF SCHD...LATEST MDL
GUIDANCE SUGGESTS FROPA SOMETIME AFT 00Z AND NUMEROUS SHOWERS
LINGERING WELL INTO THE EVE HOURS WITH PLENTY OF LOW LVL MSTR AND
CYC FLOW. NW FLOW WILL KEEP USUAL UPSLOPE AREAS IN LKLY POPS INTO
SAT WITH PSBL SHSN AT HIER ELEV...BUT PRBLY NOT TIL LATE IN THE DAY
AS MDLS ARE A LTL WARMER THAN PREV RUNS...ETA COLDEST AT 850 BUT
STILL NOT SGSTG CHG OVR TO SN UNTIL LATE SAT DUE TO WRM BNDRY LAYER.
TEMPS NEAR MOS GUIDANCE FOR FRI AND FRI NITE...BUT A FEW DEG BLW FOR
SAT TO CMPRMS WITH COLDER AVN/ETA.

ROA 59/45/50  +84
LYH 58/45/52  +84
DAN 61/47/54  +73
RNK 57/40/45  +86
BLF 59/37/40  +87

KEIGHTON

NCZ005-006-VAZ043>047-058-059-201450-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
553 AM EST FRI MAR 20 1998

...DENSE FOG ADVISORY FOR ROCKINGHAM AND CASWELL COUNTIES OF NORTH
CAROLINA THROUGH 10 AM...
...PATCHY DENSE FOG OVER THE VIRGINIA PIEDMONT THIS MORNING...

AREAS OF DENSE FOG...REDUCING VISIBILITIES TO LESS THAN A QUARTER
MILE...ARE EXPECTED TO CONTINUE THROUGH ABOUT 9 OR 10 AM ACROSS THE
WESTERN PIEDMONT COUNTIES OF NORTH CAROLINA AND VIRGINIA.  THE FOG
WILL BE MORE PATCHY CLOSER TO THE FOOTHILLS...WITH DENSE FOG
MAINLY IN THE LOWER VALLEYS.  THE FOG IS EXPECTED TO DISSIPATE BY
MID MORNING AS SHOWERS AND THUNDERSTORMS MOVE IN TO THE AREA FROM
THE SOUTHWEST.

MOTORISTS TRAVERSING THROUGH THE WESTERN PIEDMONT AREAS
OF NORTH CAROLINA AND VIRGINIA DURING THE EARLY MORNING HOURS SHOULD
BE EXTREMELY CAREFUL.

NCZ005-006-VAZ043>047-058-059-201450-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BLACKSBURG VA
553 AM EST FRI MAR 20 1998

...DENSE FOG ADVISORY FOR ROCKINGHAM AND CASWELL COUNTIES OF NORTH
CAROLINA THROUGH 10 AM...
...PATCHY DENSE FOG OVER THE VIRGINIA PIEDMONT THIS MORNING...

AREAS OF DENSE FOG...REDUCING VISIBILITIES TO LESS THAN A QUARTER
MILE...ARE EXPECTED TO CONTINUE THROUGH ABOUT 9 OR 10 AM ACROSS THE
WESTERN PIEDMONT COUNTIES OF NORTH CAROLINA AND VIRGINIA.  THE FOG
WILL BE MORE PATCHY CLOSER TO THE FOOTHILLS...WITH DENSE FOG
MAINLY IN THE LOWER VALLEYS.  THE FOG IS EXPECTED TO DISSIPATE BY
MID MORNING AS SHOWERS AND THUNDERSTORMS MOVE IN TO THE AREA FROM
THE SOUTHWEST.

MOTORISTS TRAVERSING THROUGH THE WESTERN PIEDMONT AREAS
OF NORTH CAROLINA AND VIRGINIA DURING THE EARLY MORNING HOURS SHOULD
BE EXTREMELY CAREFUL.