Alert archive / Louisiana / Flash Flood Warnings in 1998
Flash Flood Warning 44, NWS New Orleans, LA
NWS New Orleans, LA issued this flash flood warning at Sep 20, 1998, 10:30 AM CDT for Washington Parish, Louisiana; Walthall County, Mississippi. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 20, 1998, 10:30 AM CDT (15:30 UTC)
- Expired
- Sep 20, 1998, 12:35 PM CDT
- In force
- 2 hr
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
Counties Washington Parish, LA, Walthall County, MS
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 3.5 hours before the alert went out and 91 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
- 92 J/kg
- Mixed-layer CIN
- -123 J/kg
- Mixed-layer LCL
- 782 m above ground
- 0-6 km bulk shear
- 1 kt
- 0-1 km storm-relative helicity
- 31 m²/s²
- 0-3 km storm-relative helicity
- 96 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KNEW 201529 FFWNEW LAC117-MSC147-201730- BULLETIN - IMMEDIATE BROADCAST REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE NEW ORLEANS LA 1030 AM CDT SUN SEP 20 1998 THE NATIONAL WEATHER SERVICE IN NEW ORLEANS LA HAS ISSUED A... * FLASH FLOOD WARNING FOR - NORTHERN WASHINGTON PARISH IN SOUTHEASTERN LOUISIANA - SOUTHERN WALTHALL COUNTY IN SOUTHERN MISSISSIPPI * UNTIL 1235 PM CDT *AT 1025 AM NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE THUNDERTORM PRODUCING HEAVY RAIN OVER SOUTHERN WALTHALL COUNTY RADAR INDICATES THAT 3.5 TO 4.0 INCHES OF RAIN HAS FALLEN OVER SOUTHERN WALTHALL COUNTY. THE THUNDERSTORM HAS SHOWN ONLY SLOW MOTION TO THE NORTHEAST. WALTHALL COUNTY SHERIFFS OFFICE REPORTED 1 FOOT OF WATER ACROSS MISSISSIPPI HIGHWAY 27 NEAR THE WALTHALL COUNTY WASHINGTON PARISH LINE. THE HEAVY RAINFALL WILL CAUSE FLOODING OF LOW LYING AREAS AND ROADWAY THROUGH 1230 PM. IN ADDTION SOME OF THE RUNOFF FROM THIS HEAVY RAINFALL MAY MAY CAUSE FLOODING ALONG SMALL STREAMS IN NORTHERN WASHINGTON PARISH. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER GROUND.
What forecasters said that day
The local office's own words before this flash flood 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, Sep 20, 10:30 AM CDT, 0 minutes before
LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-211630- THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE NEW ORLEANS LA 1030 AM CDT SUN SEP 20 1998 TROPICAL DEPRESSION HERMINE WILL CONTINUE TO MOVE NORTHEAST AND WEAKENING. HERMINE IS EXPECTED TO DISSIPATE TONIGHT OVER NORTHERN MISSISSIPPI AND ALABAMA BORDER. THE REMNANTS OF HERMINE WILL CONTINUE TO AFFECT LOCAL REGION THROUGH THIS SUNDAY EVENING WITH SHOWERS AND THUNDERSTORMS. PERSISTING TROPICAL MOISTURES WITH WARM UNSTABLE AIRMASS WILL CAUSE SCATTERED THUNDERSTORMS MOSTLY NORTHEAST OF LINE FROM EAST FELICIANA PARISH SOUTHEAST TO ST TAMMANY PARISH INCLUDING SOUTHWEST AND COASTAL MISSISSIPPI REGIONS. FEW OF THESE THUNDERSTORMS POSSIBLY REACH SEVERE LIMITS DURING THIS SUNDAY AFTERNOON.
Special weather statement, Sep 20, 10:30 AM CDT, 0 minutes before
LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-211630- THUNDERSTORM OUTLOOK NATIONAL WEATHER SERVICE NEW ORLEANS LA 1030 AM CDT SUN SEP 20 1998 TROPICAL DEPRESSION HERMINE WILL CONTINUE TO MOVE NORTHEAST AND WEAKENING. HERMINE IS EXPECTED TO DISSIPATE TONIGHT OVER NORTHERN MISSISSIPPI AND ALABAMA BORDER. THE REMNANTS OF HERMINE WILL CONTINUE TO AFFECT LOCAL REGION THROUGH THIS SUNDAY EVENING WITH SHOWERS AND THUNDERSTORMS. PERSISTING TROPICAL MOISTURES WITH WARM UNSTABLE AIRMASS WILL CAUSE SCATTERED THUNDERSTORMS MOSTLY NORTHEAST OF LINE FROM EAST FELICIANA PARISH SOUTHEAST TO ST TAMMANY PARISH INCLUDING SOUTHWEST AND COASTAL MISSISSIPPI REGIONS. FEW OF THESE THUNDERSTORMS POSSIBLY REACH SEVERE LIMITS DURING THIS SUNDAY AFTERNOON.
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 9:05 AM CDT | Tornado Warning | LIX | Pearl River | 45 min |
| Sep 20, 9:54 AM CDT | Tornado Warning | LIX | Hancock, Harrison | 46 min |
| Sep 20, 10:23 AM CDT | Severe Thunderstorm Warning | LIX | Walthall | 62 min |
| Sep 20, 11:46 AM CDT | Tornado Warning | LIX | Pearl River | 49 min |
Nearby
Flash Flood Warnings in Louisiana, 1998Flash Flood Warnings in Mississippi, 1998Every flash flood warning in 1998
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.