Flash Flood Warning 15, NWS Midland/Odessa, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
1152 AM CDT SAT MAY 1 1999

KEEPING AN EYE ON CURRENT WEATHER TRENDS. CONCERNED ABOUT SEVERE
WEATHER DEVELOPMENT ACROSS THE MAF CWA THIS AFTERNOON AND TONIGHT.
HELICITY VALUES ARE IMPRESSIVE TODAY. 0-3KM STORM RELATIVE HELICITY
VALUES OFF OF 12Z MAF SOUNDING APPROACHING 600 M2/SEC2. ONLY AREA OF
CONVECTION AT PRESENT IS IN SE NM. STORMS ARE NOT THAT STRONG...
BUT EVEN THE GARDEN-VARIETY STORMS APPEAR TO BE ROTATING...PER
INITIAL REPORTS FROM SPOTTERS. AM CONCERNED THAT ANY SUPERCELLS THAT
DEVELOP TODAY MAY HAVE A GOOD CHANCE FOR TORNADO PRODUCTION. BEST
DYNAMIC LIFT WILL PROBABLY BE A BIT TO OUR NORTH TODAY...BUT DRYLINE
INTERACTION UPON MOIST AND UNSTABLE AIRMASS SHOULD PROVIDE PLENTY OF
POTENTIAL FOR SIGNIFICANT CONVECTION. FLASH FLOOD WATCH CONTINUING
FOR NRN PERMIAN AND SE NM...AND THIS LOOKS GOOD. STORM TOTAL PCPN
ESTIMATES FROM RADAR YESTERDAY VERIFIED VERY WELL WITH GROUND-TRUTH
REPORTS...AND THIS INDICATES THAT A BROKEN BAND OF 4-8 INCH RAINS
FELL FROM NEAR RED BLUFF DAM ALL THE WAY UP TO SEMINOLE...WITH
ISOLATED POCKETS OF 8-12 INCH RAINS. NEED TO KEEP A VERY CLOSE EYE ON
PCPN IN THIS AREA TODAY...AS SHORT TERM HEAVY RAINFALL RATES WILL
QUICKLY CAUSE PROBLEMS. LATEST OBS INDICATE THAT THE DRYLINE IS
STARTING TO ADVANCE...AND MANY AREAS W OF THE PECOS ARE MOIST AND
UNSTABLE AT THIS HOUR...WITH LITTLE CLOUD COVER. ONGOING FORECAST
LOOKS OKAY FOR NOW...MAY NEED TO TWEAK SOME TEMPS IN THE WORK ZONES
LATER ON...AND PERHAPS ADJUST SOME CLOUD COVER AMOUNTS...BUT THE MOST
IMPORTANT FACTOR WILL BE THE CONVECTIVE POTENTIAL FOR TODAY...AND
THIS IS COVERED WELL IN EXISTING PACKAGE.

DJK

NMZ027>029-TXZ045>048-050>052-057>063-067>070-074-075-079>082-020500-

THUNDERSTORM OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MIDLAND TX
859 AM CDT (759 AM MDT) SAT MAY 1 1999

THIS OUTLOOK PERTAINS TO THE FOLLOWING COUNTIES IN WEST TEXAS:

ANDREWS   CULBERSON  GLASSCOCK   MARTIN    REAGAN   UPTON
BORDEN    DAWSON     HOWARD      MIDLAND   REEVES   WARD
BREWSTER  ECTOR      JEFF DAVIS  PECOS     SCURRY   WINKLER
CRANE     GAINES     LOVING      PRESIDIO  TERRELL

AND IN SOUTHEAST NEW MEXICO:

EDDY      LEA

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHWEST MOUNTAINS OF TEXAS...AND A MODERATE RISK ACROSS THR REST
OF THE AREA TODAY AND TONIGHT...

SYNOPSIS: AN UPPER LEVEL STORM SYSTEM REMAINS OVER THE SOUTHWESTERN
U.S. THIS MORNING WITH LOW LEVEL MOISTURE CONTINUING OVER MOST OF
WEST TEXAS AND SOUTHEAST NEW MEXICO.  SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED OVER THE NORTHERN HALF OF THE OUTLOOK AREA OVERNIGHT AND
LOW CLOUDS COVERED MUCH OF THE AREA IN THE EARLY MORNING.

INITIAL STRONG THUNDERSTORM DEVELOPMENT IS EXPECTED TO OCCUR NEAR
THE DAVIS MOUNTAINS...THEN ALONG A BOUNDARY THAT STRETCHES FROM
SOUTH OF MIDLAND TO SOUTH OF CARLSBAD.  STORMS WILL LIKELY MOVE
NORTHEASTWARD INTO OTHER PARTS OF THE OUTLOOK AREA WITH THE
NORTHEASTERN SECTIONS BEING AFFECTED LAST.

THE DRYLINE WILL BE MOVING EASTWARD DURING THE DAY AS WELL AND SHOULD
BE NEAR A CARLSBAD... TO BALMORHEA... TO MARATHON LINE IN THE LATE
AFTERNOON.  DEVELOPMENT IS EXPECTED ALONG THE DRYLINE AS WELL.

SPOTTER GROUPS SHOULD BE PREPARED FOR EARLY ACTIVATION IN THE
SOUTHERN AND SOUTHWESTERN PARTS OF THE OUTLOOK AREA...POSSIBLY BY
NOON...WITH THE NORTHEASTERN SECTIONS MOST LIKELY NOT AFFECTED
UNTIL LATE IN THE AFTERNOON OR THIS EVENING.

LARGE HAIL...DAMAGING WINDS...FLOODING RAINS...AND A FEW LARGE
TORNADOES ARE ALL POSSIBLE TODAY AND TONIGHT OVER MUCH OF THE OUTLOOK
AREA.

SPOTTER ACTIVATION WILL LIKELY BE NEEDED.

FOR THE WEST CENTRAL TEXAS OUTLOOK SEE PRODUCT LBBSPSSJT.