Graphic for MPD #0361

MESOSCALE PRECIPITATION DISCUSSION 0361
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
342 AM EDT THU JUN 22 2017

AREAS AFFECTED...WESTERN LA & FAR EAST TX

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

VALID 220740Z - 221340Z

SUMMARY...CINDY IS SHOWING SOME RENEWED CONVECTION ACROSS ITS
NORTHERN AND EASTERN QUADRANTS.  HOURLY RAIN RATES UP TO 2" WITH
LOCAL AMOUNTS TO 4" ARE EXPECTED.

DISCUSSION...A CENTER OF CINDY APPEARS TO HAVE MADE LANDFALL WEST
OF CAMERON LA AT 0642Z PER RADAR IMAGERY AND IS NEARING VINTON
NEAR THE TX/LA BORDER.  SINCE THAT TIME, SHOWERS AND THUNDERSTORMS
HAVE BEEN ON THE UPSWING ACROSS ITS NORTHERN AND EASTERN QUADRANTS
-- THE STANDARD TIME CONVECTION ATTEMPTS TO FLARE UP NEAR THE
CENTER OF A MID-LEVEL CYCLONE.  PRECIPITABLE WATER VALUES OF NEAR
2.5" EXIST IN THIS REGION.  A GRADIENT IN THE INSTABILITY FIELD
EXISTS NEAR INTERSTATE 10, NEAR A CONVERGENCE ZONE AND WEAK
THERMAL GRADIENT.  EFFECTIVE BULK SHEAR OF ~30 KTS EXISTS NEAR THE
CENTER OF CINDY.

CONVERGENCE ZONES IN THE SURFACE WIND FIELD ARE EXPECTED TO MOVE
ASHORE THE UPPER TX COAST AND THROUGH IMPERIAL CALCASIEU WITH
TIME, WHICH COULD ACT AS POSSIBLE FOCI FOR CONVECTION, ALONG WITH
THE SYSTEM'S CENTER.  THE CURRENT OUTER BAND ACROSS THE LOWER
ATCHAFALAYA NEAR CINDY'S RADIUS OF MAXIMUM WIND SHOULD STAY
QUASI-STATIONARY FOR THE TIME BEING, PERHAPS SHIFTING SLIGHTLY
WESTWARD WHILE CINDY CONTINUES THE RECURVATURE PROCESS.  THE
MESOSCALE GUIDANCE IS MOSTLY TOO FAR WEST WITH CINDY AS IT HAS
BEEN FROM THE START.  THE 18Z SSEO NEIGHBORHOOD PROBABILITIES
SUGGEST A SLOW UPTICK IN CONVECTION THROUGH 12-13Z NEAR AND
SOUTHEAST OF THE CENTER WITHIN THE SYSTEM'S CENTRAL MOISTURE POOL.
 THE MESOSCALE GUIDANCE SHOWS SIGNIFICANT VARIANCE IN POSSIBLE
AMOUNTS THROUGH 14Z -- 4" SEEMS MOST SUPPORTED.  HOURLY RAIN RATES
UP TO 2" APPEAR MOST POSSIBLE WITHIN THE SYSTEM'S SOUTHEAST
QUADRANT DUE TO THE PROXIMITY OF INSTABILITY.

ROTH

ATTN...WFO...HGX...JAN...LCH...LIX...SHV...

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

LAT...LON   32319396 32009239 31209160 30019133 29279144
            29439235 29529255 29679330 29549383 29069445
            28879505 28809555 29499523 30279472 31029448
           


Last Updated: 342 AM EDT THU JUN 22 2017