Graphic for MPD #0684
MESOSCALE PRECIPITATION DISCUSSION 0684
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
525 PM EDT SUN AUG 13 2017

AREAS AFFECTED...NE NM...W OK PANHANDLE...TX PANHANDLE...EXT SE CO

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

VALID 132125Z - 140255Z

SUMMARY...SHORT-TERM STATIONARY CELLS THREATEN FLASH FLOODING IN
TX PANHANDLE BEFORE UPSCALE DEVELOPMENT OCCURS EXITING RATON
PLATEAU INTO TX PANHANDLE BY EARLY OVERNIGHT.

DISCUSSION...EXITING SHORTWAVE ACROSS THE RED RIVER VALLEY AND IN
ADVANCE OF WEAK TWIST APPROACHING FROM THE SOUTHWEST PROVIDES SOME
WEAK RIDGING SUPPORTING A MODEST UPSLOPE REGIME ACROSS THE TX
PANHANDLE INTO NE NM/SE CO.  VISIBLE IMAGERY INDICATES A WEAK LEE
CYCLONE OVER SE CO THAT IS EXPECTED TO CONSOLIDATE/DEEPEN THROUGH
THE LATE EVENING HOURS FURTHER ENHANCING LOW LEVEL MOISTURE
TRANSPORT TO THE REGION AND EVENTUALLY SUPPORT CONVECTIVE CLUSTER
TO EXPAND/MERGE INTO A LARGER MCS. 

IN THE SHORT TERM HOWEVER THERE REMAINS A SMALL AREA ACROSS THE NE
TX PANHANDLE WHERE LOW LEVEL FLOW IS INTERSECTING A LINGERING
FRONTAL BOUNDARY.  SUFFICIENT LOW LEVEL MOISTURE ENVIRONMENT
COUPLED WITH ELEVATED MIXED LAYER SUPPORTS MODEST INSTABILITY
ACROSS THE REGION TO SUPPORT STRONG UPDRAFTS.  CURRENT VISIBLE/AMA
RADAR SHOWS SUCH CELLS OVER ROBERTS BUILDING BACK NORTHWARD UNDER
THE ISALLOBARIC COMPONENT FROM THE LEE-CYCLONE DEEPENING.  THERE
IS A FAIRLY STABLE SETUP THAT SUPPORTS WESTERLY OUTFLOW WITH
UNOBSTRUCTED S AND SSE INFLOW WHILE ALSO WITHIN THE 850/7H
DEFORMATION ZONE THAT UNDER THIS DEEPENING LOW SITUATION WOULD
DRAW IT NNW.  AS SUCH CELLS ARE RELATIVELY STATIONARY.  GIVEN
AVAILABLE LOW LEVEL MOISTURE WITH MID TO UPPER 60S TDS...RAINFALL
GENERATION WILL BE STEADILY INCREASING AS THE LOCAL PROFILE
SATURATES AND LEAD TO RATES UP TO 1.75"/HR.  CURRENT AMA ESTIMATES
SEEM A BIT HIGH DUE TO HAIL CONTAMINATION ON THE RAIN RATE
ESTIMATES. STILL THE POTENTIAL FOR 3-4" TOTALS IS GOOD BEFORE THE
BEST INFLOW BACKS AND SHIFTS FOCUS TOWARD THE APPROACHING
MCS/CONVECTIVE CLUSTERS.  

HI-RES CAMS ANCHORED BY THE HRRR/ARW/NMMB SUPPORT EVENTUAL LOW
LEVEL FLOW TO BACK ACROSS THE OK/TX PANHANDLE DIRECTING STRONG
CONVERGENCE ALONG THE SURFACE FRONT AS THE LOW DESCENDS INTO NE
NM.  CONVECTION CURRENTLY OVER THE RATON PLATEAU WILL GROW UPSCALE
AND CONVERGE INTO A LARGER COMPLEX TOWARD NIGHTFALL ALLOWING FOR
BROADER DOWNDRAFTS AND RAINFALL POTENTIAL.  SOME INDICATIONS FOR
DOWNSTREAM CONVECTION TO DEVELOP ALONG THE FRONTAL ZONE IN THE
WESTERN TX PANHANDLE WOULD LIKELY BE SWEPT UP BY THE ADVANCING MCS
TOWARD 03Z.  THIS REMAINS PROBABLE AND SUPPORTS A SWATH OF 2-3"
TOTALS WITH ISOLATED 4" VALUES POSSIBLE (MAINLY AFTER 00Z)...AND
AS SUCH FLASH FLOODING IS CONSIDERED POSSIBLE.

GALLINA

ATTN...WFO...ABQ...AMA...DDC...LUB...OUN...PUB...

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

LAT...LON   37360256 36790144 36030035 35009993 33800033
            33770203 35370351 36400407 36950370


Last Updated: 525 PM EDT SUN AUG 13 2017