MESOSCALE PRECIPITATION DISCUSSION 0295
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1141 AM EDT FRI JUL 03 2015
AREAS AFFECTED...ERN TENNESSEE/KENTUCKY INTO THE SRN/CNTRL
APPALACHIAN FOOTHILLS
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE
VALID 031539Z - 032130Z
SUMMARY...FLASH FLOODING IS EXPECTED THIS AFTERNOON ON A SCATTERED
BASIS ACROSS PORTIONS OF SRN KENTUCKY/ERN TENNESSEE AND EWD INTO
THE FOOTHILLS OF THE APPALACHIANS GIVEN LOW FLASH FLOOD GUIDANCE.
RAIN RATES OF 1-2 IN/HR CAN BE EXPECTED WITH BRIEF PERIODS OF
TRAINING.
DISCUSSION...SATELLITE IMAGERY AS OF 15Z SHOWED BROKEN TO OVERCAST
SKIES OVER A MAJORITY OF THE THREAT AREA IN ADVANCE OF A MID-UPPER
LEVEL TROUGH OVER IN/IL/MO...WITH RADAR SHOWING CLUSTERS OF
CONVECTION OVER CNTRL AND ERN KENTUCKY PRODUCING ESTIMATED RAIN
RATES OF 1-2 IN/HR. THE HEAVIEST RAIN WAS OCCURRING NEAR A
MESO-VORTEX LOCATED ALONG THE CLAY/LESLIE COUNTY BORDER IN SERN
KENTUCKY WHILE ADDITIONAL CELLS WERE DEVELOPING IN ERN KENTUCKY.
12Z RAOBS AND VAD WIND PROFILE PLOTS IDENTIFIED AN 850 MB LOW OVER
FAR SRN INDIANA WHICH IS EXPECTED TO SLOWLY DRIFT NEWD THROUGH THE
AFTERNOON. DESPITE THE CLOUD COVER...WHICH SHOULD LIMIT THE DEGREE
OF INSTABILITY THIS AFTERNOON...SUFFICIENT MOISTURE OF 1.50 TO
1.75 INCHES AND TALL/SKINNY CAPES ARE EXPECTED TO CONTINUE A
THREAT FOR FLASH FLOODING WELL INTO THE AFTERNOON.
THE BIGGEST CONCERN FOR FLASH FLOODING COMES FROM ANTECEDENT
RAINFALL OVER THE PAST FEW DAYS AND FLASH FLOOD GUIDANCE OF ONLY
1-2 IN/HR WITH SMALLER EMBEDDED REGIONS WHERE THE NUMBERS ARE EVEN
LOWER. AS THE SHORTWAVE SLOWLY ADVANCES EAST DURING THE
AFTERNOON...SCATTERED CONVECTION WILL CONTINUE TO EXPAND ACROSS
THE THREAT AREA WHILE ALSO OCCURRING UNDER THE RIGHT ENTRANCE
REGION OF A STRENGTHENING UPPER JET ON THE LEE SIDE OF THE
AFOREMENTIONED UPPER TROUGH AXIS.
OTTO
ATTN...WFO...FFC...GSP...JKL...LMK...MRX...OHX...PAH...RLX...
RNK...
ATTN...RFC...LMRFC...OHRFC...SERFC...
LAT...LON 37928214 37858157 37678125 37188107 36778120
36348134 35968156 35588260 35398368 35148393
34888439 34898482 35028510 35258543 35588562
36028586 36108614 36258676 36498716 36938730
37248681 37518490 37588370 37888274
Last Updated: 1141 AM EDT FRI JUL 03 2015