MESOSCALE PRECIPITATION DISCUSSION 0063
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
429 PM EDT FRI MAY 08 2015
 
AREAS AFFECTED...CENTRAL TX/OK BORDER 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 082029Z - 090229Z
 
SUMMARY...LOOSELY ORGANIZED THUNDERSTORMS ARE EXPECTED TO
INTENSIFY OVER THE NEXT SEVERAL HOURS AS THEY MOVE EASTWARD
THROUGH THE RED RIVER VALLEY.  WITH HOURLY RAINFALL RATES UP TO 2"
POSSIBLE, FLASH FLOODING IS CONSIDERED LIKELY.

DISCUSSION...ALTHOUGH THE TEMPORAL RESOLUTION OF THE THUNDERSTORM
FORMATION THIS MORNING HAS EMULATED THAT OF YESTERDAY, ITS FORWARD
PROGRESSION AND DEVELOPMENT HAS NOT, TRACKING MORE EAST-NORTHEAST
DUE TO A GREATER RETURN OF THE OUTFLOW BOUNDARY NORTHWARD OUT OF
NORTHEAST TX AND GAINING LESS ORGANIZATION THAN SEEN YESTERDAY. 
PER THE RECENT SPC MESOANALYSIS AND THE FWD SOUNDING, CAPE VALUES
UPSTREAM ARE 2000-4000 J/KG.  PRECIPITABLE WATER VALUES ARE
1.25"-1.50" AND VAD WIND PROFILES INDICATE 25-30 KT OF 850 HPA
INFLOW AHEAD OF THE CONVECTION.

THE EXPECTATION IS FOR THE CONVECTION TO PROGRESS EAST TO
EAST-NORTHEASTWARD AND SOLIDIFY SOMEWHAT OVER THE NEXT SEVERAL
HOURS, AS 850 HPA INFLOW INCREASES SLIGHTLY FURTHER TOWARDS THE
MAGNITUDE OF THE MEAN 850-400 HPA WIND.  PRECIPITABLE WATER VALUES
INCREASE TO NEAR 1.75" THIS EVENING PER RECENT RAP FORECASTS. 
DIRECTIONAL WIND SHEAR AND AVAILABLE INSTABILITY SHOULD FOSTER
FORWARD PROGRESSION.  DESPITE THE POTENTIAL FOR MOVEMENT,
MESOCYCLONES/WAVES WITHIN THE CONVECTIVE AREA COULD LEAD TO
PERIODS OF CELL TRAINING.  HOURLY RAIN RATES UP TO 2" ARE
POSSIBLE, WHICH WOULD BE HIGHER WITH CELL MERGERS.  THIS REGION
HAS EXPERIENCED HEAVY RAINFALL OVER THE PAST COUPLE DAYS,
SATURATING AREA SOILS.  THE MESOSCALE QPF GUIDANCE GENERALLY
ADVERTISES 3-5" OF RAINFALL LOCALLY, WITH THE SSEO NEIGHBORHOOD
PROBABILITIES INDICATING THAT THE FLASH FLOOD THREAT SHOULD
INCREASE WITH TIME THROUGH 03Z.  GIVEN THE SATURATED SOILS AND
EXPECTATION FOR GREATER ORGANIZATION AND EFFICIENCY, FLASH
FLOODING IS CONSIDERED LIKELY.

ROTH

ATTN...WFO...FWD...LUB...OUN...

ATTN...RFC...ABRFC...WGRFC...

LAT...LON   35699752 35349678 34769647 33909661 33559749 
            33559949 33670093 33950159 34590011 35509856