Severe Thunderstorm Warning 170, NWS Shreveport, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
245 PM CDT FRI MAY 2 1997

AIRMASS ACRS E TX HAS HAD PLENTY OF TIME TO RECOVER THIS AFTN BEHIND
ACTIVITY THAT MOVED INTO NW LA THIS MRNG. SPECIAL SOUNDINGS AT 18Z
FROM BOTH FWD AND SHV INDICATE VERY UNSTABLE AIR WITH CAPES VARYING
FROM 3000 TO 4000 J/KG AND LIS TO NEAR -11. OF COURSE...FWD IS ALMOST
BEHIND SFC FNT ATTM BUT AIRMASS AHEAD OF IT IS PRIMED FOR DVLPMT AS
S/WV SEEN IN SAT IMAGERY ACRS WRN/CNTRL OK MOVS INTO THE AREA THIS
AFTN AND EVNG. WUD EXPECT DVLPMT FIRST ACRS NE TX THEN MOVG EWD ACRS
LA AND AR AS FNT PUSHES THRU THE AREA THIS EVNG.

MODELS ALL PROVIDE SIMILAR TIMING FOR SFC FNT INTO NW PORTIONS OF
CWA BY ERLY EVNG THEN THRU CWA BY MIDNIGHT. DIFFERENCES IN THE MODELS
ARISE HWVR. NGM LOOKS AS THOUGH IT IS TOO DRY WHILE AVN KEEPS MAIN
DYNAMICS N OF BULK OF THE AREA. THIS WUD ACCOUNT FOR LOWER POPS
GENERATED BY THE MODELS. ETA APPEARS TO BE MODEL OF CHOICE AS IT
NORMALLY HANDLES MSTR BETTER THAN NGM. WILL UP POPS FROM GUIDANCE
NUMBERS FOR THE EVNG ACRS THE AREA. MENTION OF SVR STILL VERY MUCH
NEEDED. LOOKS LIKE SQUALL LINE AND ISOLATED TORNADIC DVLPMT AHEAD OF
THE LINE THIS EVNG. QUESTION BECOMES HOW FAST AIRMASS OVER LA WILL
RECOVER TO SUPPORT SUSTAINED SVR WX INO NW LA. WINDS IMMEDIATELY BEHIND
THE BOUNDARY THIS MRNG BECAME SRLY AGN AND GUD SRLY INFLOW REESTABLISHING
ACRS THE AREA. LOOKS LIKE AIRMASS WILL RECOVER ENUF.

FOR LA WILL NEED TO KEEP FFA GOING. ANY ADDITIONAL RAINFALL WILL CAUSE
PROBLEMS ACRS THE NRN PARTS OF LA THIS EVNG AND TONIGHT.

BY LATE TONIGHT AND ERLY SAT DRIER AIR SHUD PUSH INTO THE AREA FOM
THE WEST AT ALL LVLS. SOME CAA NOTED SHUD HELP PUSH WINDS SAT BUT
STRENGTHb OF THE SUN SHUD OVERCOME THE CAA AND TEMPS FROM DROPPING
VERY FAR. WILL GO CLOSER TO WARMER NGM TEMPS FOR SAT AND SUN.

SHV 56/75/50/78 5000   MLU 58/74/50/78 6000

18

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
1257 PM CDT FRI MAY 02 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1230 PM    GRAND CANE                LA   FLOODING
05/02/97   DE SOTO                        HIGH WATER OVER BOTH LANES
                                          OF US 171.  CARS STALLING
                                          IN WATER.

10

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
110 PM CDT THU MAY 02 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0105 PM    10 S MANSFIELD            LA   TORNADO
05/02/97   DE SOTO                        REPORTED BY DE SOTO PARISH
                                          SHERIFF OFFICE.

10

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SHREVEPORT LA
110 PM CDT THU MAY 02 1997

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0105 P`M    10 S MANSFIELD            LA   TORNADO
05/02/97   DE SOTO                        REPORTED BY DE SOTO PARISH
                                          SHERIFF OFFICE.

10

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-022030-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
145 PM CDT FRI MAY 2 1997

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER NORTHEAST
TEXAS... SOUTHEAST OKLAHOMA... SOUTHWEST ARKANSAS... AND NORTHERN
LOUISIANA FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING.

A VERY UNSTABLE AIR MASS IS IN PLACE OVER THE FOUR STATE AREA THIS
AFTERNOON. THUNDERSTORMS HAVE ALREADY MOVED THROUGH NORTHERN
LOUISIANA AND EXTREME SOUTHERN ARKANSAS DURING THE EARLY AFTERNOON
HOURS. STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO REFORM OVER
NORTHEAST TEXAS AND SOUTHWEST ARKANSAS DURING THE MID TO LATE
AFTERNOON HOURS.

THESE THUNDERSTORMS WILL MOVE EAST AND NORTHEAST INTO NORTHERN
LOUISIANA AND ACROSS SOUTHERN ARKANSAS DURING THE LATE AFTERNOON AND
EVENING. SOME OF THESE THUNDERSTORMS WILL LIKELY BE SEVERE WITH LARGE
HAIL AND DAMAGING WINDS. TORNADOES ARE ALSO POSSIBLE DURING THE MID
AFTERNOON THROUGH EVENING HOURS.

STORM SPOTTERS MAY BE ACTIVATED LATE THIS AFTERNOON AND EVENING IN
NORTHEAST TEXAS... SOUTHWEST ARKANSAS... AND NORTHERN LOUISIANA.

3

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-022030-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
145 PM CDT FRI MAY 2 1997

THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER NORTHEAST
TEXAS... SOUTHEAST OKLAHOMA... SOUTHWEST ARKANSAS... AND NORTHERN
LOUISIANA FOR THE REMAINDER OF THIS AFTERNOON AND THIS EVENING.

A VERY UNSTABLE AIR MASS IS IN PLACE OVER THE FOUR STATE AREA THIS
AFTERNOON. THUNDERSTORMS HAVE ALREADY MOVED THROUGH NORTHERN
LOUISIANA AND EXTREME SOUTHERN ARKANSAS DURING THE EARLY AFTERNOON
HOURS. STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO REFORM OVER
NORTHEAST TEXAS AND SOUTHWEST ARKANSAS DURING THE MID TO LATE
AFTERNOON HOURS.

THESE THUNDERSTORMS WILL MOVE EAST AND NORTHEAST INTO NORTHERN
LOUISIANA AND ACROSS SOUTHERN ARKANSAS DURING THE LATE AFTERNOON AND
EVENING. SOME OF THESE THUNDERSTORMS WILL LIKELY BE SEVERE WITH LARGE*
HAIL AND DAMAGING WINDS. TORNADOES ARE ALSO POSSIBLE DURING THE MID
AFTERNOON THROUGH EVENING HOURS.

STORM SPOTTERS MAY BE ACTIVATED LATE THIS AFTERNOON AND EVENING IN
NORTHEAST TEXAS... SOUTHWEST ARKANSAS... AND NORTHERN LOUISIANA.

3