Flash Flood Warning 13, NWS Nashville, TN

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
1001 AM CST THU JAN 24 2002

AT MID MORNING A COLD FRONT HAD MOVED THROUGH THE NASHVILLE AREA.
THE NARROW BAND OF RADAR RETURNS IS THE FRONT ON OUR 88D. THE FRONT
EXTENDED FROM W PA THROUGH CENTRAL KY...SW MIDDLE TN AND THEN
BECOMING A STATIONARY FRONT OVER SE TX...WHERE A SURFACE WAVE WAS
LOCATED.

12Z SURFACE ANALYSES SHOWED DRIER AIR MOVING PRIMARILY INTO THE N
PARTS OF THE MID STATE AT THE 850 AND 700 MB LEVELS...WITH ONLY WEAK
COLD ADVECTION OR NONE AT ALL FROM 850 THROUGH 500 MB. SOME WARM
ADVECTION NOTED FROM LA INTO MS...ASSOCIATED WITH A SURFACE WAVE
OVER SE TX.

THE LATEST RUC MODEL FORECASTS A WEAK SURFACE WAVE TO MOVE NE ALONG
THE FRONT THIS AFTERNOON...AND FORECAST TO BE LOCATED OVER N AL IN
THE MID AFTERNOON. THIS MEANS OVERRUNNING PRECIP FOR PRIMARILY OUR E
AND SE ZONES THIS AFTERNOON...WITH THE RUC SHOWING A GROWING AREA OF
90 PERCENT OR HIGHER MEAN RELATIVE HUMIDITY THERE.

CURRENT RADAR LOOP SHOWS THE LARGE AREA RAIN HAS CLEARED OUR NW AND
N CENTRAL ZONES...BUT REMAINS OVER THE PLATEAU AND SOUTHERN THIRD OF
THE MID STATE. ONE THING THAT BOTHERS ME AT THIS TIME IS THAT THE
MEM RADAR IS SHOWING SOME SHOWERS AS FAR N AS N CENTRAL AR...AND
MOVING TO THE NE. THEY ARE NOT MAKING MUCH PROGRESS HOWEVER...DUE TO
THE DRIER AIR AT 850 AND 700 MB THERE...AND THE W TO E FLOW.

WILL MOST LIKELY CONTINUE WITH A CHANCE OF PRECIP OVER OUR NW AND N
CENTRAL ZONES FOR THIS AFTERNOON AND HIT HEAVY RAIN POTENTIAL FOR
MAINLY S AND SE ZONES AGAIN...EXPECIALLY LATER THIS AFTERNOON.

HAVE NOT LOOKED AT TEMPS YET...BUT WILL MOST LIKELY HAVE TO MAKE
SOME ADJUSTMENTS THERE TOO.

WILL REMOVE THE FLASH FLOOD WATCH FOR NW AND SOME N CENTRAL ZONES
FOR THIS AFTERNOON...AND EXTEND WATCH INTO EARLY TONIGHT FOR S AND
SE.

.BNA...FLASH FLOOD WATCH FOR S AND SE MIDDLE TN INTO EARLY TONIGHT.

STEIGERWALDT