Severe Thunderstorm Warning 121, NWS Shreveport, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
230 PM CST FRI MAR 5 1999

ETA/NGM BOTH SHOW AREA OF BEST LI/S PROGRESSING FROM OK/TX AT 00Z TO
CENTRAL AND NORTHEAST LA AT 12Z. ETA CAPES JUMP TO 2000 RANGE ALONG
FRONTAL BOUNDARY FROM SW AR TO WACO AT 00Z THEN IN THE 1300-1500
RANGE FROM SHV THROUGH LFK AT 06Z. THIS PROG DID QUITE WELL WITH
TUESDAY SYSTEM...ALTHOUGH TUESDAY NUMBERS WERE HIGHER.  SURFACE
FRONT STILL PROGGED NEAR IDABEL 00Z...SHV 06Z...MLU 11Z...WHICH
CORRELATES WELL WITH INSTABILITY FEATURES MENTIONED.

GOOD CAP ON 12Z SOUNDINGS THIS MORNING BUT FORECAST SOUNDINGS SHOW
THIS WILL FADE SIGNIFICANTLY IN TIME FOR MAIN PERIOD OF STORM
INTEREST---00Z TO 06Z. ETA INITIALIZED THE 250 MB WINDS BETTER THAN
NGM...AND ETA EXTENDS JET CORE FROM IDABEL TO FTW AT 00Z...PLACING
TYLER IN RIGHT REAR QUAD. A SHORT LIVED FEATURE AS JET REALLY
PROGRESSES QUICKLY TO EASTERN GREAT LAKES AND CENTRAL APPALACHIANS
BY 06Z. BY 12Z THE CWA BECOMES INFLUENCED BY RIGHT FRONT QUAD OF
NEXT JET MAX WHICH WILL BE MOVING OFF THE CENTRAL ROCKIES.

MY HUNCH IS THAT THIS WILL NOT BE A REPEAT OF TUESDAY/S SQUALL LINE.
THIS ORGANIZES AND DEPARTS QUICKLY...AND THE INSTABILITY VALUES ARE
NOT AS IMPRESSIVE. WITH THAT SAID...CHANCE FOR SEVERE STORMS STILL
PRESENT.

MODELS HAVE BEEN CONSISTENT IN POINTING TO A PLEASANT SATURDAY
DAYTIME. MILD TEMPS WITH A MODERATE NORTH/NORTHEAST BREEZE OVER THE
AREA. COOL SUNDAY MORNING AND AFTERNOON BUT SUNDAY SEEMS DRY TOO.
RETURN FLOW MOISTENS THINGS UP SUNDAY NIGHT IN LIEU OF NEXT STORM
SYSTEM...WHICH STILL LOOKS DYNAMICALLY IMPRESSIVE...LOOMING FOR
MONDAY. 72 HR AVN FOR MONDAY MORNING SAYS MOISTURE WILL BE ABUNDANT
IN THE 1000/500 MB LAYER ESPECIALLY COMPARED TO THE MOISTURE DEPTH
EXTANT TODAY. REVIEW OF 48 HR MOISTURE PROGS OF ALL THREE MODELS
SHOWS MUCH OF THE MOISTURE ALOFT ..850 TO 700 MB..SEEMS TO COME FROM
UPSLOPE EFFECT OVER W TX AND E NM. FLOW OFF OF GULF JUICES SFC UP
FROM HOUSTON TO BROWNSVILLE NORTHWESTWARD.

AFTER MONDAY NIGHT...COOLER AND DRIER WEATHER ON TAP FOR TUES/WED.
LONG TERM MRF BACKED OFF OF LATE WEEK COLD/WET SPELL NEXT WEEK...NOW
ITS JUST COOL/MOIST. WHAT WILL IT FORECAST TOMORROW?

SHV 52/69/42/59 4000  MLU 57/67/42/58 6100
TXK 50/65/39/57 4000  TYR 52/69/43/59 2000
LFK 57/73/49/63 3000

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