Severe Thunderstorm Warning 16, NWS Morristown, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MORRISTOWN TN
238 AM EST SAT JAN 23 1999

THANKS FOR COORD CALLS CRW..BNA..RDU..MEM

CURRENT SURFACE ANALYSIS SHOWS SURFACE LOW PRESSURE LOCATED OVER
WESTERN TENNESSEE ATTM.  WATER VAPOR PIC SHOWS UPPER LEVEL LOW
STARTING TO KICK EAST. CURRENT TOWER DATA ACROSS THE AREA IS
CONTINUING TO SHOW SOUTH-SOUTHEAST WINDS GUSTING TO 45 MPH AT
ELEVATIONS ABOVE 1500 FEET.  KMRX/KHTX SHOWING 50-60KTS AT 2-3000
FEET. BOTH KMRX/KHTX SHOWING LEADING EDGE OF SHRA/TSRA MAKING A SLOW
EASTWARD PROGRESS.

ALL MODELS ARE IN CLOSE AGREEMENT WITH LIFTING THE SURFACE LOW TO
THE NORTHEAST AND KICKING THE UPPER LOW NORTHEAST AS A 150 KT JET
MAX COMES AROUND THE BACKSIDE OF THE LOW. THE ATMOSPHERE IS
COMPLETELY SATURATED FROM THE SURFACE UP TO 500 MB...SO HEAVY RAIN
IS LIKELY FOR MOST OF THE AREA TODAY. THERE IS ENHANCED LIFT TODAY
AS RIGHT REAR QUAD THE JET MAX MOVES OVER THE AREA...ALSO WITH
STRONG UPPER LEVEL DIVERGENCE AND UPSLOPE FLOW INTO THE MOUNTAINS.
CURRENT RADAR TRENDS AND SLOW MOVEMENT OF THE STORM...TRAINING
EFFECT OF THE SHRA/TSRA COULD CAUSE FLOODING ACROSS THE AREA...AS
FFG VALUES FOR ONE HOUR ARE AT ONE INCH OR LESS. KHTX ALREADY
SHOWING ONE VALUES OF UP TO 1.5 INCHES...SO FLOODING WILL BE
POSSIBLE. AS FOR NORTHEAST TENNESSEE AND MOST OF THE CENTRAL EAST
VALLEY THIS AFTERNOON...DOWNSLOPING (RAIN SHADOW EFFECT) WITH THE
MOUNTAINS...HEAVY RAINS WILL BE POSSIBLE BUT FLOODING POTENTIAL NOT
AS GREAT...WOULD LIKE TO CONTINUE FLASH FLOOD WATCH THAT IS
ONGOING...AND LET DAY SHIFT DECIDE IF VALLEY SECTIONS NEED TO BE
INCLUDED IN THE FLASH FLOOD WATCH.

THE PRESSURE GRADIENT ALSO REMAINS TIGHTLY PACKED THROUGH THIS
EVENING AND WITH WINDS ALREADY GUSTING TO NEAR ADVISORY CRITERIA...
WOULD LIKE TO CONTINUE AND EXPAND ONGOING HIGH WIND ADVISORY FOR THE
ENTIRE CWA.

SEVERE WEATHER POTENTIAL LOOKS LIMITED...ONLY CONCERN WOULD BE IF
SOME OF THE WINDS ALOFT MIX DOWN TO THE SURFACE...BUT THIS SHOULD
BE ISOLATED AT BEST.

AS FOR TEMPS...FWC SEEMS TO HAVE THE BEST HANDLE ON CURRENT TEMPS.
WITH ALL THE CLOUDS AND RAIN IN THE AREA...TEMPERATURES TODAY
SHOULD REMAIN NEARLY STEADY OR SLOWLY RISE TO NEAR 70 DEGREES FOR
ALL AREAS.

FOR TODAY...CATEGORICAL SHRA/TSRA FOR ALL AREAS. (100 PERCENT).
HEAVY AT TIMES. HIGHS REMAINING NEARLY STEADY NEAR 70 DEGREES.
SOUTH WINDS 20 TO 30 MPH AND GUSTY.

TONIGHT...DECREASING PRECIP FROM WEST TO EAST AS SFC CLD FRONT MOVES
INTO THE AREA.

SUNDAY...MOSTLY CLOUDY AND COOLER. HIGHS IN THE MIDDLE 50S.

THANKS...PDK