Severe Thunderstorm Warning 71, NWS Midland/Odessa, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND TX
200 PM CDT FRI APR 30 1999

SIGNIFICANT CONVECTION CONTINUING THIS AFTERNOON. AIRMASS ACROSS THE
AREA REMAINS MOIST AND UNSTABLE...AND A SERIES OF SHORTWAVES
ROTATING AROUND THE UPPER LOW OVER AZ WILL LIKELY KEEP CONVECTION
ACTIVE ACROSS THE AREA THROUGH THIS EVENING. AXIS OF THE THETA-
E RIDGE ACROSS THE AREA REMAINS ROUGHLY ACROSS THE MIDDLE SECTION OF
THE CWA...AND PROGS GRADUALLY SHIFT THIS INTO THE EASTERN CWA BY
TOMORROW AFTERNOON. UPPER LEVEL DIFLUENCE ACROSS THE CWA WAS QUITE
IMPRESSIVE THIS MORNING. AREA OF BEST DIFLUENCE WILL PROPOGATE INTO
NORTHERN TX AND SOUTHERN OK LATE TONIGHT. DRYLINE TO THE WEST HAS
BEEN ADVANCING VERY SLOWLY THROUGHOUT THE DAY...WITH STORMS FIRING
UP ALONG ITS BOUNDARY CONTINUOUSLY AND TRAINING NWD AND NEWD. LOOKS
AS IF A NARROW DRY SLOT OVR FAR WEST TX WILL BEGIN ROTATING INTO THE
AREA LATER TONIGHT...AFFECTING PORTIONS OF THE CWA UNTIL EARLY
MORNING. WILL STILL KEEP SCT POPS IN AREA OVERNIGHT WITH THE MOIST
AIRMASS AND PVA ALOFT...BUT WILL NEED TO KEEP THIS IN MIND.

MODELS SLOWLY ADVANCE THE LOW AND BEGIN LIFTING IT OUT LATE
TOMORROW. MODELS ALWAYS TRY TO LIFT THESE UPPER LOWS OUT TOO
QUICKLY...SO I WILL TAKE THIS INTO ACCOUNT WITH THE FORECAST. BY
MIDDAY TOMORROW...IT LOOKS AS IF THE UPPER LEVEL FLOW WILL BECOME
MORE SWLY WITH THE APPROACH OF THE LOW...AND THIS SHOULD HELP THE
DRYLINE PUSH FURTHER EWD. WITH THE MOIST AIRMASS AND UPPER LEVEL
DISTURBANCES PROPOGATING AROUND THE LOW...WILL NEED TO KEEP POPS UP
FOR TOMORROW. TOMORROW NIGHT THE LOW WILL STILL BE IN THE VICINITY...
AND WILL KEEP POPS IN AS WELL.

THE MAIN CHALLENGE WILL BE WHAT TO DO WITH SUNDAY. MODELS LIFT LOW
AND ASSOCIATED VORT ENERGY NWD AWAY FROM THE AREA...AND DRIER SFC
AIR IS PROGGED TO OVERRUN THE AREA. HOWEVER...CONSIDERING THE FACT
THAT THE LOW WILL PROBABLY MOVE OUT MORE SLOWLY...WILL HAVE TO KEEP
SOME CLOUDS AROUND DURING THE DAY...AND POSSIBLY EVEN SOME LINGERING
MORNING POPS.

LBB...WORKZONES FORTHCOMING...WILL BE A FEW MINUTES LATE.

PRELIM TEMPS/POPS
MAF 57/75/54/79 6542
CNM 51/75/47/80 543-
MRF 45/74/41/78 222-
P07 60/78/59/79 3431

DJK