Severe Thunderstorm Warning 98, NWS Midland/Odessa, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
418 PM CDT THU MAY 25 2000

SHORT TERM...
MUCH TO TALK ABOUT AND NOT MUCH TIME...PLEASE REFER TO SPC MESO
DISCUSSIONS AND OUTLOOKS FOR PERTINENT INFORMATION.  A SURFACE LOW
IS LOCATED INVOF MAF WITH A WEAK SURFACE BOUNDARY EXTENDING
NORTHEAST FROM THERE.  A STATIONARY FRONT IS MORE OR LESS COLOCATED
WITH THE STRATUS SHIELD ALONG THE I-40 CORRIDOR.  ALOFT...THE MAIN
UPPER LEVEL SHORTWAVE IS MOVING ACROSS AZ AT PRESENT...WITH SEVERAL
LOBES OF ENERGY ROTATING ACROSS THE AREA.  SPECIAL 18Z SOUNDING FROM
MAF SHOWED A MODEST AMOUNT OF CIN BUT CONSIDERABLE INSTABILITY.  AN
UPPER JET LOCATED ACROSS AZ THIS MORNING IN HAND ANALYSES IS EXPECTED
TO PROGRESS ACROSS THE REGION THIS EVENING...AND AGEOSTROPICALLY-
FORCED ASCENT IN THE RIGHT ENTRANCE REGION OF THIS JET SHOULD BE
ENOUGH TO REMOVE THE CIN AND ALLOW SCATTERED CONVECTION TO FIRE
FROM MAF NORTHEAST ALONG THE BOUNDARY.  FARTHER SOUTH...WIDELY
SCATTERED CONVECTION IS BEGINNING TO DEVELOP...MAINLY ACROSS PECOS
COUNTY WHERE HEATING HAS BEEN ENOUGH TO GET PARCELS TO THEIR LFCS.
OBSERVED AND FORECAST WEAK LOW LEVEL SR FLOW COMBINED WITH CAPES AOA
4000 J/KG SUGGEST THAT CONVECTION WILL TREND TOWARD AN HP MODE...WITH
HAIL AND DOWNBURST WINDS THE PRIMARY SEVERE THREAT.  THE TORNADO
THREAT IS MINIMAL GIVEN HIGH LFCS AND THE AFOREMENTIONED LACK OF
RESPECTABLE SR LOW LEVEL FLOW.

LONG TERM...
A SURFACE TROUGH SHOULD BEGIN TO DEVELOP ALONG THE WESTERN ZONES
TONIGHT AS THE MAIN SHORTWAVE TROUGH SWINGS OUT OVER THE SOUTHERN
ROCKIES.  THIS TROUGH WILL THEN PROGRESS EASTWARD ACROSS THE PLAINS
DURING THE DAY.  DESPITE SOUTHWESTERLY LOW LEVEL FLOW AND GOOD
INSOLATION...IT WILL NOT BE AS WARM TOMORROW OWING TO SOME MODEST
THICKNESS COOLING.  OTHER THAN A SLIGHT CHANCE FOR SOME DIURNAL
THUNDER ACROSS THE DAVIS AND CHISOS MOUNTAINS...CONVECTION IS NOT
EXPECTED.  SURFACE ANTICYCLOGENESIS GETS GOING OVER THE CENTRAL HIGH
PLAINS AS THE SHORTWAVE TROUGH COMES OUT...AND THIS IN TURN DRIVES A
COLD FRONT INTO THE CWFA SATURDAY.  DONT EXPECT MUCH IN THE WAY OF
CONVECTION WITH THIS FEATURE GIVEN QUESTIONABLE LOW LEVEL MOISTURE
AND UNFAVORABLE DYNAMICS...ALTHOUGH AN ISOLATED STORM COULD FIRE OVER
THE LOWER TRANS PECOS SATURDAY AFTERNOON.  CONFIDENCE IN THIS IS LOW
ENOUGH TO PRECLUDE MENTION IN THE UPCOMING ZONES.  SLIGHTLY COOLER
TEMPERATURES ARE EXPECTED ACROSS MOST OF THE AREA SATURDAY BEHIND THE
FRONT.

REAL LONG TERM...
BACK INTO THE OVEN AS UPPER HEIGHTS BUILD OVER THE AREA.  WENT ON THE
OPTIMISTIC SIDE FOR HIGHS THROUGH THE REMAINDER OF THE MEMORIAL DAY
WEEKEND...BUT WOULD NOT BE SURPRISED TO SEE LATER FORECASTS REVISE
THESE HIGHS INTO THE 105 TO 110 RANGE BY TUESDAY.  SIG WX NIL GIVEN
POOR MOISTURE AND WEAK DYNAMICS.

THATS A WRAP...LINE SCORES FOLLOW...70.

THE PRELIMINARY GUIDANCE BELOW IS FOR COORDINATION PURPOSES ONLY.
OFFICIAL FORECASTS ARE CONTAINED WITHIN THE WEST TEXAS/SOUTHEASTERN
NEW MEXICO ZONE FORECAST.

MAF  68/ 98/68/ 95    3100
LSA  66/ 98/66/ 95    3-00
E41  68/ 98/68/ 97    3100
6R6  72/100/72/100    2---
MRF  57/ 92/55/ 91    22--
CNM  66/ 99/66/ 96    2000

.MAF...
TX...NONE.
NM...NONE.

NMZ027>029-033-034-TXZ045>048-050>053-057>063-067>070-074-075-
079>082-258-252200-

THUNDERSTORM OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
1255 PM CDT THU MAY 25 2000

...THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT ACROSS THE
NORTHERN THIRD OF THE PERMIAN BASIN AND SOUTHEAST NEW MEXICO...

THERE IS THE THREAT OF THUNDERSTORMS THIS AFTERNOON AND
TONIGHT...PARTICULARLY ACROSS THE NORTHERN PERMIAN BASIN AND
SOUTHEAST NEW MEXICO.

VERY WARM TEMPERATURES IN THE MID LEVELS OF THE ATMOSPHERE HAS
PREVENTED THUNDERSTORM ACTIVITY DEVELOPING ACROSS THE REGION THE
LAST FEW DAYS. HOWEVER AS A TROUGH OF LOW PRESSURE APPROACHES THE
REGION FROM THE DESERT SOUTHWEST COOLER AIR IN THE MID LEVELS OF THE
ATMOSPHERE WILL OVER OVERSPREAD THE REGION THIS AFTERNOON AND
TONIGHT. AT THIS TIME THE BEST MID LEVEL COOLING...AND THEREFORE
GREATEST POTENTIAL FOR THUNDERSTORMS...IS FORECASTED TO TAKE PLACE
NORTH OF A CARLSBAD...ANDREWS...BIG SPRING LINE. ANY THUNDERSTORMS
THAT CAN DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE WITH LARGE
HAIL AND DAMAGING WINDS THE MAIN THREAT.

THE THUNDERSTORM THREAT MAY HAVE TO BE LATER EXTENDED SOUTHWARD
ACROSS MORE OF THE PERMIAN BASIN DEPENDING ON THE AMOUNT OF MID
LEVEL COOLING THAT TAKES PLACE.

SPOTTER ACTIVATION IS NOT ANTICIPATED AT THIS TIME...HOWEVER...
EMERGENCY MANAGERS SHOULD MONITOR THIS SITUATION AND STAY TUNED TO
THE LATEST UPDATES SHOULD CONDITIONS CHANGE.

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NMZ027>029-033-034-TXZ045>048-050>053-057>063-067>070-074-075-
079>082-258-260100-

THUNDERSTORM OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
441 PM CDT THU MAY 25 2000

...MODERATE RISK OF SEVERE THUNDERSTORMS EXPECTED OVER THE NORTHERN
PERMIAN BASIN TONIGHT...

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER THE NORTHERN
PERMIAN BASIN TONIGHT.  THE MODERATE RISK AREA IS FOR THAT PART OF
WEST TEXAS EAST OF AN SEMINOLE TO ODESSA LINE...AND NORTH OF AN
ODESSA TO COLORADO CITY LINE.  FARTHER SOUTH...A FEW SEVERE
THUNDERSTORMS MAY OCCUR...MAINLY EAST OF AN ODESSA TO FORT STOCKTON
LINE.

A SURFACE LOW WAS LOCATED LATE THIS AFTERNOON NEAR MIDLAND...WITH A
SURFACE BOUNDARY EXTENDING NORTHEAST FROM THIS LOW TO NEAR POST.
STRONG DAYTIME HEATING AND AN APPROACHING UPPER LEVEL STORM SYSTEM
HAS MADE THE AIRMASS OVER THE NORTHERN PERMIAN BASIN STRONGLY
UNSTABLE.  THUNDERSTORMS ARE EXPECTED TO DEVELOP THROUGH EARLY
EVENING ALONG THIS BOUNDARY.  ANY STORMS THAT DO DEVELOP WILL BECOME
SEVERE QUICKLY...WITH LARGE HAIL AND DAMAGING WINDS THE PRIMARY
SEVERE WEATHER THREATS.  WEAK WINDS IN THE LOWEST LEVELS OF THE
ATMOSPHERE WILL LIMIT THE POTENTIAL FOR THESE STORMS TO PRODUCE
TORNADOES...BUT AN ISOLATED TORNADO MAY BE POSSIBLE WITH ANY STORM
THAT TRACKS ALONG THE SURFACE BOUNDARY.

SOUTH OF I-20...ISOLATED SEVERE THUNDERSTORMS MAY DEVELOP LATE THIS
AFTERNOON THROUGH THIS EVENING...MAINLY EAST OF AN ODESSA TO FORT
STOCKTON LINE.  LARGE HAIL AND DAMAGING WINDS ALSO WILL BE THE
PRIMARY SEVERE WEATHER THREATS.

THE THREAT OF THUNDERSTORMS SHOULD DIMINISH LATE THIS EVENING AS THE
LOW LEVELS OF THE ATMOSPHERE BECOME MORE STABLE WITH LOSS OF DAYTIME
HEATING.

LAW ENFORCEMENT AGENCIES...EMERGENCY MANAGEMENT OFFICIALS...STORM
SPOTTER GROUPS...AND OTHER INTERESTED CONCERNS SHOULD MONITOR THIS
SITUATION AND TAKE APPROPRIATE ACTION SHOULD SEVERE WEATHER THREATEN
YOUR AREA.  SPOTTER ACTIVATION LIKELY WILL BE REQUESTED OVER THE
MODERATE RISK AREA LATE THIS AFTERNOON THROUGH THE EVENING HOURS...
WITH SPOTTER ACTIVATION POSSIBLE SOUTH OF I-20.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL TELEVISION OR RADIO
STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS
CONCERNING THIS POTENTIALLY DANGEROUS SEVERE WEATHER THREAT.

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