MESOSCALE PRECIPITATION DISCUSSION 0108
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
556 PM EDT MON APR 10 2017

AREAS AFFECTED...CENTRAL TO NORTHERN TX...

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 102155Z - 110210Z

SUMMARY...INITIAL CONVECTION FIRING ALONG BAROCLINIC ZONE MAY
TRAIN/BACKBUILD DURING THE NEXT 3-4 HOURS...PARTICULARLY ALONG THE
SOUTHWESTERN EXTENT OF THE LINE. HOURLY RAINFALL RATES MAY
APPROACH 1.50 INCHES WITHIN THE MORE ROBUST THUNDERSTORMS.

DISCUSSION...THE 21Z SURFACE ANALYSIS INDICATED A SLOW-MOVING COLD
FRONT EXTENDING FROM FAR SOUTHEASTERN OK THROUGH THE DALLAS
METROPLEX AND SOUTH OF SAN ANGELO TX. ALONG AND AHEAD OF THIS
BAROCLINIC ZONE...UPDRAFTS CONTINUE TO GROW WITHIN A VERY
MOIST/UNSTABLE AIR MASS. CURRENT OBSERVATIONS INDICATE SURFACE DEW
POINTS HAVE REACHED 70 DEGREES WITHIN THIS BAND OF ENHANCED
BUOYANCY. THE 20Z RAP OBJECTIVE ANALYSIS DEPICTED SURFACE-BASED
CAPE VALUES IN THE 2000-3000 J/KG WITH ANY INHIBITION ALREADY
ERODED. ADDITIONALLY...A HEALTHY PLUME OF MOISTURE CONTINUES TO
ADVECT NORTHWARD FROM THE GULF OF MX WITH LOCAL PWAT VALUES
NEARING/EXCEEDING 1.25 INCHES. BASED ON THE SPC SOUNDING
CLIMATOLOGY PAGE...THIS IS ROUGHLY IN THE 90TH PERCENTILE FOR
MID-APRIL.

THE LATEST OBSERVATIONS FROM MESONET DATA SHOWS SOME FAIRLY HEFTY
RAINFALL AMOUNTS IN THE INITIAL CONVECTION. WHILE THE INITIAL
STORM MODE IS MORE SEVERE IN NATURE...THESE CELLS HAVE BEEN
PRODUCING RAINFALL TOTALS OVER 2 INCHES JUST OUTSIDE OF PLANO TX.
SUCH RATES SHOULD CONTINUE WITHIN ADDITIONAL DEVELOPMENT ALONG THE
SLOW-MOVING COLD FRONT. MANY OF THE CAMS SUGGEST A PERIOD OF
TRAINING BEING POSSIBLE AS STORMS FIRE ALONG MUCH OF THE EXTENT OF
THE BOUNDARY. LATER IN THE FORECAST...THERE IS A STRONG SIGNAL THE
STORMS WILL BECOME MORE OUTFLOW/COLD POOL DOMINANT AND SINK
SOUTHWARD TOWARD THE TX GULF COAST. BASED ON EVALUATION OF THE
RECENT CAMS AND THE EXPECTED EVOLUTION THIS EVENING...THERE IS A
CHANCE FOR TRAINING ALONG THE SOUTHWEST FLANK OF THIS LINE WHERE
STRONGER INSTABILITY AND INFLOW ARE LIKELY TO BE COLLOCATED. AS
FLASH FLOOD GUIDANCE VALUES ARE ON THE HIGHER END OF THE
SPECTRUM...WIDESPREAD HYDROLOGIC ISSUES ARE NOT EXPECTED.

RUBIN-OSTER

ATTN...WFO...EWX...FWD...HGX...LZK...SHV...SJT...TSA...

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

LAT...LON   34259435 34079351 33519332 32689343 31599440
            30549612 29779764 29389843 29479917 29849957
            30319977 30959962 31759812 32539706 33549613