MESOSCALE PRECIPITATION DISCUSSION 0576
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
608 PM EDT THU JUL 27 2017

AREAS AFFECTED...NORTHWEST OK...NORTHERN TX PANHANDLE

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

VALID 272205Z - 280230Z

SUMMARY...AMPLE MOISTURE/INSTABILITY WITH VERY SLOW/ZERO CELL
MOTIONS SUPPORT  LOCALIZED BUT EFFICIENT THUNDERSTORMS CAPABLE OF
PRODUCING FLASH FLOODING CONDITIONS.

DISCUSSION...EXPERIMENTAL GOES-16 MULTI-SPECTRAL SUITE DEPICTS
LAST EVENING'S MCV REMAINS FAIRLY STATIONARY NEAR THE CENTRAL
TX/OK PANHANDLE BOARDER.  THIS MCV SITS NEARLY VERTICALLY ALIGNED
WITH UPPER LEVEL 3-2H ANTICYCLONE.  AS SUCH MODEST LOW LEVEL
CONVERGENCE IS SUPPORTED BY WEAK BUT HIGHLY SUPPORTIVE UPPER LEVEL
EVACUATION.  IN THE LARGER SCALE HOWEVER...AREA OF CONCERN IS
LOCATED IN THE NORTHEAST RETURN BRANCH/DEFORMATION ZONE FROM
ANOMALOUSLY DEEP/RICH MOISTURE SOURCE ACROSS THE OZARKS TO TN
VALLEY.  THIS MST ADVECTION/WEAK UPSLOPE FLOW HAS BROUGHT SFC TDS
TO THE LOW 70S ACROSS NE OK AND THE OK/N TX PANHANDLES WITH
2000-2500 J/KG MLCAPE AND TPWS AT 2.0" INCREASING TOWARD THE
NORTHEAST.  

AS SUCH TIGHT MCV CIRCULATION HAS PROVIDED SUFFICIENT MST
CONVERGENCE NEAR THE CENTER WHICH HAS BEEN CYCLING AND SLOWLY
DRIFTING EAST WITH THE MCV OVER OCHILTREE INTO LIPSCOMB COUNTY
WITH RATES UP TO 2"/HR.  RECENT IR/VIS TRENDS ALSO INDICATES
STRENGTHENING CONVERGENCE ALONG OUTER BAND OF THE MCV/OLD OUTFLOW
FROM LAST EVENING ACROSS NORTH OF THE RED RIVER INTO WEST CENTRAL
OK...WITH ADDITIONAL CONVECTION FILLING IN BETWEEN.  THIS INCREASE
IN COVERAGE SUPPORTS A LARGER AREAL THREAT FOR RAINRATES OF 2"/HR
AND LOCALIZED TOTALS OF 3-4" LEADING TO POSSIBLE FLASH FLOODING
CONDITIONS OVER THE NEXT FEW HOURS. 

GALLINA

ATTN...WFO...AMA...DDC...LUB...OUN...

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

LAT...LON   37120027 36849829 35979783 35139807 34640039
            34880119 35340151 35770191 36120209 36900193