Alert archive / Louisiana / Severe Thunderstorm Warnings in 1990
Severe Thunderstorm Warning 20, NWS New Orleans, LA
NWS New Orleans, LA issued this severe thunderstorm warning at May 21, 1990, 2:42 PM CDT for Tangipahoa Parish, Washington Parish, Louisiana. It was in force for 63 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- May 21, 1990, 2:42 PM CDT (19:42 UTC)
- Expired
- May 21, 1990, 3:45 PM CDT
- In force
- 63 min
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
Counties Tangipahoa Parish, LA, Washington Parish, LA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 21, 2:47 PM CDT | Thunderstorm Wind 0 | Tangipahoa, LA | |
| May 21, 2:55 PM CDT | Hail 0.88 | Washington, LA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 7.7 hours before the alert went out and 74 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 2055 J/kg
- Mixed-layer CIN
- -50 J/kg
- Mixed-layer LCL
- 807 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 56 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.4
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, May 21, 12:49 PM CDT, 1 hour 53 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-211900- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 1235 PM CDT MON MAY 21 1990 A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT... AN AREA OF THUNDERSTORMS WERE OCCURRING OVER SOUTHERN MISSISSIPPI BETWEEN JACKSON AND NATCHEZ EXTENDING EAST TO NEAR MERIDIAN. THE AREA WAS MOVING SOUTH AT 25 MILES AN HOUR. SCATTERED PATCHES OF LIGHT RAIN AND SHOWERS WERE ALSO OCCURRING OVER EXTREME SOUTHEAST MISSISSIPPI AND SOUTHWEST WEST ALABAMA. THERE ARE NO THUNDERSTORMS OVER SOUTHEAST LOUISIANA AT THE PRESENT TIME HOWEVER THUNDERSTORM ACTIVITY MAY DEVELOP A*CROSS THE AREA THIS AFTERNOON. THESE THUNDERSTORMS COULD BE CAPABLE OF PRODUCING STONG GUSTY WINDS...FREQUENT LIGHTNING...POSSIBE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 12:53 PM CDT, 1 hour 49 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-211900- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 1235 PM CDT MON MAY 21 1990 A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT... AN AREA OF THUNDERSTORMS WERE OCCURRING OVER SOUTHERN MISSISSIPPI BETWEEN JACKSON AND NATCHEZ EXTENDING EAST TO NEAR MERIDIAN. THE AREA WAS MOVING SOUTH AT 25 MILES AN HOUR. SCATTERED PATCHES OF LIGHT RAIN AND SHOWERS WERE ALSO OCCURRING OVER EXTREME SOUTHEAST MISSISSIPPI AND SOUTHWEST ALABAMA. THERE ARE NO THUNDERSTORMS OVER SOUTHEAST LOUISIANA AT THE PRESENT TIME HOWEVER THUNDERSTORM ACTIVITY MAY DEVELOP AC/ROSS THE AREA THIS AFTERNOON. THESE THUNDERSTORMS COULD BE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING...POSSIBLE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 1:55 PM CDT, 47 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-212000- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 145 PM CDT MON MAY 21 1990 A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT... A LINE OF THUNDERSTORMS WAS OCCURRING FROM SOUTH OF MERIDIAN EXTENDING SOUTHWEST TO BETWEEN HAZELHURST AND MC COMB AND CONTINUING SOUTHWEST TO BETWEEN NATCHEZ MISSISSIPPI AND SIMMESPORT LOUISIANA. OTHERWISE PATCHES OF LIGHT RAIN WITH SHOWERS AND THUNDESTORMS CONTINUED ACROSS SOUTHERN MISSISSIPPI AND SOUTHWEST ALABAMA. THERE IS NO THUNDERSTORM ACTIVITY OVER SOUTHEAST LOUISIANA HOWEVER PRECIPITATION IS DEVELOPING NEAR THE AREA AND THE THUNDERSTORM ACTIVITY OVER MISSISSIPPI IS SOUTH. THUNDERSTORMS ARE POSSIBLE AND WILL BE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING...POSSIBLE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 1:59 PM CDT, 43 minutes before
LAZ008>010-012>014-MSZ010>014-ALZ016-212000- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 145 PM CDT MON MAY 21 1990 A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR TANGIPAHOA AND WASHINGTON PARISHES IN SOUTHEAST LOUISIANA UNTIL 5PM CDT... A LINE OF THUNDERSTORMS WAS OCCURRING FROM SOUTH OF MERIDIAN EXTENDING SOUTHWEST TO BETWEEN HAZELHURST AND MC COMB AND CONTINUING SOUTHWEST TO BETWEEN NATCHEZ MISSISSIPPI AND SIMMESPORT LOUISIANA. OTHERWISE PATCHES OF LIGHT RAIN WITH SHOWERS AND THUNDESTORMS CONTINUED ACROSS SOUTHERN MISSISSIPPI AND SOUTHWEST ALABAMA. THERE IS NO THUNDERSTORM ACTIVITY OVER SOUTHEAST LOUISIANA HOWEVER PRECIPITATION IS DEVELOPING NEAR THE AREA AND THE THUNDERSTORM ACTIVITY OVER MISSISSIPPI IS MOVING SOUTH. THUNDERSTORMS ARE POSSIBLE AND WILL BE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING... POSSIBLE HAIL AND HEAVY RAINS.
Special weather statement, May 21, 2:31 PM CDT, 11 minutes before
LAZ009-212030- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 230 PM CDT MON MAY 21 1990 ...A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL 5 PM CDT FOR EAST CENTRAL LOUISIANA EXCEPT FOR ASCENSION PARISH... RADAR SHOWED AN AREA OF THUNDERSTORMS EXTENDING EAST TO WEST ALONG THE MISSISSIPPI/LOUISIANA BORDER FROM NORTHEAST OF KENTWOOD WESTWARD NORTH OF ANGOLA CONTINUING INTO LOUISIANA NEAR JUST NORTH OF MARKSVILLE. THE THUNDERSTORMS WERE MOVING SOUTHWARD AROUND 25 MPH. THESE THUNDERSTORMS WILL PRODUCE STRONG GUSTY WINDS AND SMALL HAIL AS THEY MOVE INTO EAST AND WEST FELICIANA AND ST. HELENA PARISHES DURING THE NEXT HOUR. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN...AND CLOSE TO...THE WATCH AREA. PERSONS IN EAST CENTRAL LOUISIANA SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND/OR WARNINGS.
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 12:31 PM CDT | Severe Thunderstorm Warning | LIX | Catahoula, Concordia | 74 min |
| May 21, 2:51 PM CDT | Severe Thunderstorm Warning | LIX | East Feliciana, West Feliciana | 69 min |
| May 21, 2:51 PM CDT | Severe Thunderstorm Warning | LIX | Saint Helena | 69 min |
| May 21, 4:11 PM CDT | Severe Thunderstorm Warning | LIX | Saint Bernard | 49 min |
Nearby
Severe Thunderstorm Warnings in Louisiana, 1990Every severe thunderstorm warning in 1990
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.