MESOSCALE PRECIPITATION DISCUSSION 0089
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
330 AM EDT SUN APR 02 2017

AREAS AFFECTED...SRN EDWARDS PLATEAU...WRN HILL COUNTRY OF TX

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

VALID 020729Z - 021229Z

SUMMARY...CONTINUED FLASH FLOOD THREAT AS SHORTWAVE LIFTS OUT OF
NORTHEAST MEXICO.

DISCUSSION...CURRENT GOES-16 WV/IR DEPICT A VERY DEEP COLD
CONVECTIVE COMPLEX WITH PERCOLATING OVERSHOOTING TOPS ACROSS
SOUTHEAST VAL VERDE COUNTY REACHING TO -75C AT TIMES.  FURTHER
UPSTREAM HOWEVER...WV CHANNELS SHOW A VERY SUBTLE ARC INDICATIVE
OF THE MEAN MID-LEVEL TROF/SHORTWAVE AXIS AT THAT IS STARTING TO
LIFT NORTH.  SURROUNDING CIRRUS/STRATUS IS ERODING WITH LOSS OF
THIS LARGE SCALE DPVA/ASCENT AS IT SHIFTS NORTHEASTWARD.  SOUTHERN
MOST STORM/OVERSHOOTING TOP HAS ALREADY STARTED TO WEAKEN SLIGHTLY
AS IT WAS ANCHORED ON STRONG EASTERLY FLOW ON THE TERRAIN...AND
WILL BEGIN TO TRACK ENE.  A DRY PUNCH WILL BEGIN TO PRESS
NORTHEAST OUT OF THE SERRANIAS DEL BURRO IN THE NEXT FEW
HOURS...STILL STRONG EASTERLY LOW LEVEL FLOW AND MOISTURE FLUX
WILL CONTINUE TO MAINTAIN CONVECTION ALONG THE EASTERN FLANK OF
THE ELEVATED MIXED LAYER CONTINUING TO BE FED BY SOLID 2000+ J/KG
INSTABILITY. SFC TDS IN THE MID TO UPPER 60S AND DEEPER OVERALL
TPW TO 1.5" WILL ALLOW FOR EFFICIENT RAINFALL PRODUCTION WITH
THESE CELLS WITH RATES OF 2.0"/HR LIKELY TO CONTINUE.  GIVEN A FEW
MORE HOURS OF VERY SLOW MOTIONS BEFORE THE MAIN FORCING
LIFTS...ADDITIONAL 3-4" MAY BE POSSIBLE PARTICULARLY ACROSS SE VAL
VERDE/KINNEY/EDWARDS AND REAL COUNTIES.  

AS SHORTWAVE LIFTS NORTHWARD INTO THE EDWARDS PLATEAU TOWARD
12Z...CONTINUE UPPER LEVEL DIVERGENCE WILL SUPPORT UPPER VERTICAL
VELOCITY EVEN AS THE LOW LEVEL FLOW REGIME BEGINS TO VEER FROM
EASTERLY TO SOUTHERLY REDUCING MST CONVERGENCE/FLUX. AND AS SUCH
FORWARD PROPAGATION TO THE EAST AND NORTHEAST WILL COMMENCE
REDUCING DURATION OF HEAVY RAINFALL LIMITING EXTREME TOTALS TOWARD
11-12Z THOUGH WITH REMAINING SUFFICIENT FORWARD PROPAGATING
CONVERGENCE OF MOIST/UNSTABLE AIR RATES WOULD REMAIN A CONCERN FOR
CONTINUED FLASH FLOODING THREAT BUT MORE LOCALIZED PARTICULARLY IN
NARROW CHANNEL/COMPLEX/RUGGED TERRAIN OF THE WESTERN HILL COUNTY. 


GALLINA

ATTN...WFO...EWX...SJT...

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

LAT...LON   30699947 30699850 30019829 29429889 28830035
            29040071 29260087 29490119 29630127 30100118
            30460031