MESOSCALE PRECIPITATION DISCUSSION 0326
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
122 AM EDT WED JUL 08 2015
 
AREAS AFFECTED...CENTRAL AND NORTHERN TX...EASTERN OK 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 080521Z - 081121Z
 
SUMMARY...CONVECTION IS EXPECTED TO EXPAND IN COVERAGE OVER THE
NEXT FEW HOURS...WITH A LIKELIHOOD OF TRAINING SHOWERS AND
THUNDERSTORMS WHICH WILL BE CAPABLE OF PRODUCING FLASH FLOODING.


DISCUSSION...SATELLITE IMAGERY SHOWS A SSW/NNE AXIS OF GRADUALLY
COOLING CONVECTIVE TOPS...EXTENDING FROM CENTRAL TX INTO
EAST-CENTRAL OK...AND GENERALLY NEAR A LINE FROM JUST NORTH OF
KJCT TO KMWL TO KADH. THE CONVECTION IS FORMING AS A SHORTWAVE
TROUGH LIFTS GRADUALLY NORTHEAST ACROSS THE RED RIVER VALLEY AND
HELPS ADVANCE A WEAK AREA OF LOW PRESSURE UP ALONG A FRONTAL ZONE.
THIS WAVE OF LOW PRESSURE IS HELPING TO ENHANCE THE LOW LEVEL
MOISTURE/INSTABILITY TRANSPORT INTO THE AREA. REGIONAL VAD WIND
PROFILER DATA SHOWS S/SW 850 MB FLOW APPROACHING 40 KTS AND
BECOMING ALIGNED NEARLY PARALLEL TO THE SURFACE FRONT AND
SHORTWAVE AXIS ALOFT.

PWATS ARE VERY HIGH ACROSS THE RED RIVER VALLEY...WITH LOCAL
GPS-DERIVED PWAT VALUES RUNNING IN EXCESS OF 2.25 INCHES. THIS
COUPLED WITH THE COOLING CLOUDS TOPS OVER THE LAST HOUR SUGGESTS
INCREASINGLY HEAVY RAINFALL RATES BEGINNING TO IMPACT THE REGION.

CONSECUTIVE RUNS OF THE HRRR ARE INDICATING AN AXIS OF HEAVY
TRAINING CONVECTION OVERNIGHT AS CELLS DEVELOP AND LIFT NNE ALONG
THE FRONT AND IN TANDEM WITH THE ADVANCE OF LOW PRESSURE. RAINFALL
AMOUNTS OF 3 TO 6 INCHES ARE EXPECTED THROUGH SUNRISE WITH LOCALLY
HEAVIER AMOUNTS GIVEN SUCH DEEP MOISTURE AND HIGH RAINFALL RATE
POTENTIAL. THE WET ANTECEDENT CONDITIONS AT LEAST LOCALLY ARE
EXPECTED TO ENHANCE THE POTENTIAL FOR FLASH FLOODING. WILL
CONTINUE TO MONITOR.

ORRISON

ATTN...WFO...FWD...OUN...SJT...TSA...

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

LAT...LON   36789603 36719488 35309527 33289707 32379776 
            31279857 30529944 30320011 30620043 31399996 
            32289983 33149896 33979816 35199731