Flash Flood in Virginia, February 16, 2003

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
500 AM EST SUN FEB 16 2003

THE FOLLOWING ARE ALL THE FORECAST DISCUSSIONS FROM THE PAST 24
HOURS...WITH THE MOST RECENT ON TOP. THIS PROVIDES A HISTORY OF THE
DEVELOPMENT OF THE CURRENT FORECAST.

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EARLY MORNING FORECAST DISCUSSION
500 AM EST SUN FEB 16 2003

RADAR SHOWING A BREAK IN THE PRECIP...BUT IT SHOULD RETURN BEFORE
TOO LONG AS UPPER TROUGH AND SURFACE LOW NEARS.  WILL GO WITH 100
POPS FOR TODAY.  WITH OVER-SATURATED GROUND AND MORE PRECIP ON THE
WAY...WILL EXTEND THE FLOOD WATCH UNTIL THIS AFTERNOON.  SURFACE OBS
IN THE ADVISORY AREA SHOWING TEMPERATURES IN THE MID 30S...BUT WITH
TEMPERATURES IN THE UPPER 20S JUST TO THE EAST...WILL CONTINUE THE
WINTER WEATHER ADVISORY TODAY.  MORE RAIN EXPECTED TONIGHT...WILL GO
WITH LIKELY TO CATEGORICAL POPS FOR TONIGHT.  MAY SEE MORE MIX IN
THE NORTHEAST TONIGHT AND MONDAY MORNING.  ANOTHER ADVISORY MAY BE
NEEDED... BUT WILL LET THE DAY SHIFT DECIDE.  DRY WEATHER MOVING IN
MONDAY NIGHT...FINALLY.

CHA   56  39  45  34 / 100  60  20   0
TYS   53  38  43  33 / 100  70  40   0
TRI   42  34  39  29 / 100  90  60   0
OQT   53  38  43  33 / 100  70  40   0

.MRX...
NC...FLOOD WATCH FOR TODAY FOR ZONES NCZ060>061.

TN...WINTER WEATHER ADVISORY FOR TODAY FOR ZONES
TNZ018...TNZ045...TNZ047.

FLOOD WATCH FOR TODAY FOR ZONES TNZ012>018...TNZ035>047...
TNZ067>074...TNZ081>087...TNZ098>102.

VA...WINTER WEATHER ADVISORY FOR TODAY FOR ZONES VAZ006...VAZ008.

FLOOD WATCH FOR TODAY FOR ZONES VAZ001>002...VAZ005>006...VAZ008.

GH

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EVENING FORECAST DISCUSSION (UPDATE)
900 PM EST SAT FEB 15 2003

FORECAST FOR TONIGHT GENERALLY APPEARS TO BE ON TRACK. PRECIP HAS
BECOME MORE CONVECTIVE IN NATURE. SOME LIGHTNING STRIKES ARE
OCCURRING IN THE SOUTHERN TIER COUNTIES OF THE FORECAST AREA AT THIS
TIME. CURRENT FORECAST HAS THIS SCENARIO HANDLED WELL. TEMPS LOOK
REASONABLE. NO CHANGES ARE WARRANTED AT THIS TIME.

LCM

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AFTERNOON FORECAST DISCUSSION
345 PM EST SAT FEB 15 2003

CURRENT SURFACE ANALYSIS SHOWS A QUASI-STATIONARY WARM FRONT ALONG
THE NORTHERN TN AREAS...WITH WARM MOIST MOVING INTO THE FORECAST
AREAS. LIGHT TO MODERATE RAIN CONTINUES ACROSS THE FORECAST AREA AS
THE LOW PRESSURE SYSTEM OVER THE LOWER MS VALLEY SLOWLY MOVES EAST.
EXPECT RAIN TO GRADUALLY INCREASE IN COVERAGE AND INTENSITY TONIGHT
AS THE SURFACE LOW AND ITS ASSOCIATED UPPER TROUGH MOVE INTO THE TN
VALLEY. INSTABILITY INCREASES SOMEWHAT TONIGHT AS THIS LOW
APPROACHES THE AREA...SO WILL CONTINUE A MENTION OF A FEW TSTORMS.
WILL CONTINUE THE FLOOD WATCH TONIGHT...MAINLY FOR THE THREAT OF
FLOODING OF RIVERS AND STREAMS. THIS LOW IS PROGGED BY THE MODELS TO
MOVE EVEN SLOWER THAN PREVIOUSLY THOUGHT...SO THIS FLOOD WATCH MAY
NEED TO BE EXTENDED THROUGH SUNDAY.

COLDER AIR BUILDS SOUTH AND WEST FROM THE MID ATLANTIC REGION LATE
TONIGHT INTO SUNDAY...WHICH WILL COULD SET THE STAGE FOR THE
DEVELOPMENT OF SOME FREEZING RAIN AND SLEET ACROSS PORTIONS OF
SOUTHWEST VIRGINIA AND EXTREME NORTHEAST TENNESSEE. RIGHT NOW..ONLY
LIGHT ACCUMULATIONS (GENERALLY LESS THAN A FOURTH OF AN INCH) ARE
EXPECTED...SINCE THE BULK OF THE COLDER AIR SHOULD REMAIN FURTHER
EAST ACROSS NORTH CAROLINA AND CENTRAL VIRGINIA.

AS FOR TEMPS...NGM AND AVN NUMBER SHOW DISCREPANCIES AND WILL
GENERALLY COMPROMISE BETWEEN THE TWO THROUGH THE PERIOD.

THE FOLLOWING NUMBERS ARE PRELIMINARY AND FOR COORDINATION ONLY:

CHA   52  52  38  44 / 100 100  60  20
TYS   47  47  36  40 / 100 100  70  40
TRI   38  38  34  38 / 100 100  90  60
OQT   47  47  36  40 / 100 100  70  40

DMG

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LATE MORNING FORECAST DISCUSSION (UPDATE)
1015 AM EST SAT FEB 15 2003

CURRENT SURFACE ANALYSIS SHOWS A STRONG LOW PRESSURE SYSTEM CENTERED
OVER ARKANSAS...WITH A WARM FRONT EXTENDING EAST ACROSS THE TN/KY
STATE LINE. SOME PATCHY DENSE FOG IS STILL BEING REPORTED ACROSS THE
FORECAST AREA...BUT THIS FOG SHOULD GRADUALLY LIFT LATER THIS
MORNING AS WINDS PICK UP. AREA RADARS REVEAL LIGHT TO MODERATE RAIN
CONTINUING ACROSS MOST OF THE FORECAST AREA...WITH HEAVIER RAIN AND
A FEW TSTORMS OCCURRING ACROSS MIDDLE TN. MODELS SHOW LIFT
INCREASING ACROSS THE FORECAST AREA LATER THIS AFTERNOON AND
EVENING...AS THIS SURFACE LOW AND ITS ASSOCIATED STRONG UPPER TROUGH
APPROACH. BASED ON FUTURE 24 HOUR FORECASTED RAINFALL...A FEW RIVERS
ARE EXPECTED TO RISE ABOVE FLOOD STAGE IN THE AREA...AND HAVE ISSUED
RIVER FLOOD WARNINGS ACCORDINGLY.

CURRENT FORECAST LOOKS TO BE ON TRACK...BUT WILL UPDATE LATER THIS
MORNING MAINLY TO TWEAK MORNING WORDING.

DMG