Graphic for MPD #0182
 
MESOSCALE PRECIPITATION DISCUSSION 0182
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
241 AM EDT WED JUL 09 2014
 
AREAS AFFECTED...EXTREME SOUTHERN TN/NORTHERN MS/NORTHERN AL... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 090641Z - 090941Z
 
SUMMARY...CONVECTION WHICH WAS TRAINING ALONG THE TN/AL/MS BORDER
HAS FINALLY BEGUN TO DROP SLOWLY TOWARD THE SOUTH. HOWEVER...CELL
MOTIONS CONTINUE TO BE SLOW ENOUGH TO BRING A RISK OF ADDITIONAL
FLASH FLOODING ACROSS NORTHERN SECTIONS OF MS/AL. 

DISCUSSION...A COMPLEX OF THUNDERSTORMS HAVE BEEN ONGOING MUCH OF
THE NIGHT AND FOCUSED ALONG A RATHER SHARP MID/UPPER MOISTURE
GRADIENT PER WATER VAPOR IMAGERY. RAINFALL RATES OF 1 TO 2 INCHES
IN AN HOUR HAVE BEEN COMMONPLACE WITHIN THE STRONGER PRECIPITATION
CORES WITH DOPPLER ESTIMATES OF 3 TO 5 INCHES OCCURRING IN A 3
HOUR PERIOD. THIS HAS EASILY EXCEEDED LOCAL FFG VALUES. WHILE THE
SPATIAL EXTENT OF COLDER CLOUD TOPS HAVE DECREASED IN RECENT
SCANS...THERE STILL APPEARS TO BE A NARROW CORRIDOR OF ENHANCED
VERTICAL LIFT ALONG THE TN/MS BORDER. THIS IS EVIDENT BY THE
ABUNDANCE OF LIGHTNING ACTIVITY OCCURRING WITHIN THE COLDER TOPS.
MEANWHILE...MOISTURE REMAINS WELL ABOVE AVERAGE WITH PWATS IN THE
2 TO 2.25 INCH RANGE. DURING THE NEXT FEW HOURS...THE 05Z RAP
SUGGESTS LOW-LEVEL INFLOW WILL REMAIN STRONG WITH 925-850 MB WINDS
AROUND 30 KNOTS. THE GUIDANCE ALSO SHOW THE MEAN STEERING FLOW
BECOMES NEARLY ALIGNED WITH THE INFLOW WHICH MAY LEAD TO ANOTHER
PERIOD OF SLOW-MOVING/TRAINING CONVECTION. WHILE THE THREAT IS NOT
AS SIGNIFICANT AS BEFORE...THE COMPLEX STILL HAS A HISTORY OF
PRODUCING FLASH FLOODS. WILL REASSESS IN A FEW HOURS TO DETERMINE
IF ANOTHER MESOSCALE DISCUSSION WILL NEED TO BE ISSUED.


RUBIN-OSTER

ATTN...WFO...OHX...BMX...HUN...MEG...JAN...

ATTN...RFC...ABRFC...LMRFC...SERFC...

LAT...LON   34759053 35139002 35188848 34878670 33948638 33548687
            33548854 33698965 33939056 34759053 


Last Updated: 241 AM EDT WED JUL 09 2014