Severe Thunderstorm Warning 83, NWS Shreveport, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SHREVEPORT LA
230 PM CST FRI APR 4 1997

NOT MUCH TIME THIS AFTERNOON WITH ACTIVITY STARTING TO POP ACROSS W
HALF OF CWA. COORD WITH NEW AND THE POSSIBILITY OF PRE-FRONTAL
HEAVY RAINFALL TONIGHT AND HEAVY RAINFALL IN ASSOCIATION WITH SQUALL
LINE DURING THE EARLY MORNING HOURS SAT...WILL ISSUE FLASH FLOOD WATCH
FOR NW HALF OF LA WEST OF A LINE FROM JUNCTION CITY TO CYPRESS LA.
HAVE DECIDED NOT TO INCLUDE NORTHEAST LOUISIANA IN FFA DUE TO EXPECTED
ACCELERATION OF THE LINE AS IT MOVES FURTHER EAST. WOULD LIKE TO SEE
AT LEAST CHANCE POPS ACROSS NW HALF OF LA FOR SECOND PERIOD AND
WORD IT MAINLY TOWARDS MORNING BECAUSE OF UNCERTAINITY OF SQUALL
LINE PLACEMENT. MOS NUMBERS LOOK GOOD...MY NUMBERS TO FOLLOW...

SHV 64/76/53/72  +510     MLU 65/73/52/72  +630

13

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-041700-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
930 AM CST FRI APR 4 1997

...SIGNIFICANT SEVERE WEATHER EVENT POSSIBLE LATE THIS AFTERNOON AND
INTO THE NIGHT FOR THE FOUR STATE AREA WHICH INCLUDES NORTHEAST TEXAS
...SOUTHEAST OKLAHOMA...SOUTHWEST ARKANSAS...AND NORTH LOUISIANA...

A DEEP UPPER LEVEL STORM SYSTEM WILL BE MOVING OUT OF THE DESERT
SOUTHWEST AND NORTHWEST MEXICO TODAY AND IT APPEARS THAT THIS SYSTEM
WILL LIKELY RESULT IN A SIGNIFICANT SEVERE WEATHER EPISODE ACROSS THE
FOUR STATES REGION LATE THIS AFTERNOON INTO TONIGHT. THUNDERSTORMS
ARE EXPECTED TO CONTINUE OFF AND ON THROUGH THIS AFTERNOON...BUT THE
MORE LIKELY SEVERE WEATHER THREAT WILL BE LATER AS THE UPPER LOW
APPROACHES.

SOME OF THESE STORMS WILL LIKELY BECOME SEVERE AS MOIST UNSTABLE AIR
FROM THE GULF OF MEXICO IS TRANSPORTED OVER THE REGION BY STRONG
SOUTHERLY WINDS. SOME STORMS COULD APPROACH NORTHEAST TEXAS BY
LATE AFTERNOON AND THEN SPREAD EAST OVER REMAINING SECTIONS DURING
THE NIGHT. THE SYSTEM WILL MOVE QUICKLY ACROSS THE REGION OVERNIGHT
WITH A COLD FRONT OVER WESTERN SECTIONS BEFORE MIDNIGHT AND THE
EASTERN HALF AROUND AND AFTER MIDNIGHT.

DUE TO THE FACT THAT WINDS WILL BE TURNING CLOCKWISE AND INCREASING
IN SPEED WITH HEIGHT IT APPEARS THAT STORMS THAT FORM TODAY COULD
DEVELOP ROTATION AND ISOLATED STORMS MAY PRODUCE TORNADOES. EVEN IF
NO TORNADOES FORM...THE STRENGTH OF THE WINDS ALOFT WILL RESULT IN A
SIGNIFICANT THREAT OF VERY DAMAGING STRAIGHT-LINE WINDS AS WELL AS
LARGE HAIL. AS WELL AS A SEVERE WEATHER EPISODE...SOME OF THE
THUNDERSTORMS WILL PRODUCE VERY HEAVY RAINFALL IN A SHORT PERIOD OF
TIME RESULTING IN RAPID WATER RUNOFF AND PONDING OF WATER IN LOW
LYING AND POOR DRAINAGE AREAS.

EMERGENCY MANAGEMENT OFFICIALS...STORM SPOTTERS AND HAM RADIO
OPERATORS SHOULD BE PREPARED FOR ACTIVATION POSSIBLY BY LATE THIS
AFTERNOON OVER PARTS OF NORTHEAST TEXAS AND SOUTHEAST OKLAHOMA
AND INTO THE NIGHT...THEN FOR SOUTHWEST ARKANSAS AND NORTH LOUISIANA
TONIGHT.

THOSE OFFICIALS AND SPOTTERS IN NORTHEAST TEXAS AND MCCURTAIN
COUNTY OKLAHOMA SHOULD BE PREPARED FOR ACTIVATION AS EARLY
AS THE AFTERNOON HOURS...THOSE IN SOUTH ARKANSAS AND NORTH CENTRAL
LOUISIANA MAY NOT BE NEEDED UNTIL THE EVENING HOURS AND
EASTERN SECTIONS AROUND AND AFTER MIDNIGHT.

SIX

ARZ050-051-059>061-070>073-LAZ001>006-010>014-017>022-OKZ077-TXZ096-
097-108>112-124>126-136>138-149>153-165>167-041700-

THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE SHREVEPORT LA
930 AM CST FRI APR 4 1997

...SIGNIFICANT SEVERE WEATHER EVENT POSSIBLE LATE THIS AFTERNOON AND
INTO THE NIGHT FOR THE FOUR STATE AREA WHICH INCLUDES NORTHEAST TEXAS
...SOUTHEAST OKLAHOMA...SOUTHWEST ARKANSAS...AND NORTH LOUISIANA...

A DEEP UPPER LEVEL STORM SYSTEM WILL BE MOVING OUT OF THE DESERT
SOUTHWEST AND NORTHWEST MEXICO TODAY AND IT APPEARS THAT THIS SYSTEM
WILL LIKELY RESULT IN A SIGNIFICANT SEVERE WEATHER EPISODE ACROSS THE
FOUR STATES REGION LATE THIS AFTERNOON INTO TONIGHT. THUNDERSTORMS
ARE EXPECTED TO CONTINUE OFF AND ON THROUGH THIS AFTERNOON...BUT THE
MORE LIKELY SEVERE WEATHER THREAT WILL BE LATER AS THE UPPER LOW
APPROACHES.

SOME OF THESE STORMS WILL LIKELY BECOME SEVERE AS MOIST UNSTABLE AIR
FROM THE GULF OF MEXICO IS TRANSPORTED OVER THE REGION BY STRONG
SOUTHERLY WINDS. SOME STORMS COULD APPROACH NORTHEAST TEXAS BY
LATE AFTERNOON AND THEN SPREAD EAST OVER REMAINING SECTIONS DURING
THE NIGHT. THE SYSTEM WILL MOVE QUICKLY ACROSS THE REGION OVERNIGHT
WITH A COLD FRONT OVER WESTERN SECTIONS BEFORE MIDNIGHT AND THE
EASTERN HALF AROUND AND AFTER MIDNIGHT.

DUE TO THE FACT THAT WINDS WILL BE TURNING CLOCKWISE AND INCREASING
IN SPEED WITH HEIGHT IT APPEARS THAT STORMS THAT FORM TODAY COULD
DEVELOP ROTATION AND ISOLATED STORMS MAY PRODUCE TORNADOES. EVEN IF
NO TORNADOES FORM...THE STRENGTH OF THE WINDS ALOFT WILL RESULT IN A
SIGNIFICANT THREAT OF VERY DAMAGING STRAIGHT-LINE WINDS AS WELL AS
LARGE HAIL. AS WELL AS A SEVERE WEATHER EPISODE...SOME OF THE
THUNDERSTORMS WILL PRODUCE VERY HEAVY RAINFALL IN A SHORT PERIOD OF
TIME RESULTING IN RAPID WATER RUNOFF AND PONDING OF WATER IN LOW
LYING AND POOR DRAINAGE AREAS.

EMERGENCY MANAGEMENT OFFICIALS...STORM SPOTTERS AND HAM RADIO
OPERATORS SHOULD BE PREPARED FOR ACTIVATION POSSIBLY BY LATE THIS
AFTERNOON OVER PARTS OF NORTHEAST TEXAS AND SOUTHEAST OKLAHOMA
AND INTO THE NIGHT...THEN FOR SOUTHWEST ARKANSAS AND NORTH LOUISIANA
TONIGHT.

THOSE OFFICIALS AND SPOTTERS IN NORTHEAST TEXAS AND MCCURTAIN
COUNTY OKLAHOMA SHOULD BE PREPARED FOR ACTIVATION AS EARLY
AS THE AFTERNOON HOURS...THOSE IN SOUTH ARKANSAS AND NORTH CENTRAL
LOUISIANA MAY NOT BE NEEDED UNTIL THE EVENING HOURS AND
EASTERN SECTIONS AROUND AND AFTER MIDNIGHT.

SIX