Alert archive / Louisiana / Flash Flood Warnings in 1987
Flash Flood Warning 2, NWS New Orleans, LA
NWS New Orleans, LA issued this flash flood warning at May 25, 1987, 5:08 PM CDT for Saint Martin Parish, Louisiana. It was in force for 4 hr.
The area
The counties it named.
The facts
- Issued
- May 25, 1987, 5:08 PM CDT (22:08 UTC)
- Expired
- May 25, 1987, 9:00 PM CDT
- In force
- 4 hr
- Issued by
- NWS New Orleans, LA
- Area
- Whole counties
County Saint Martin Parish, LA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 12:00Z, 10.1 hours before the alert went out and 153 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
- 1962 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 842 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- -57 m²/s²
- 0-3 km storm-relative helicity
- -30 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 252210
FFWNEW
LAC099-007-101-109-260200-
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
508 PM CST MON MAY 25 1987
THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING
EFFECTIVE UNTIL 900 PM CST FOR PEOPLE IN THE FOLLOWING PARISHES...
IN SOUTHEAST LOUISIANA
...LOWER ST. MARTIN...ST. MARY...ASSUMPTION...TERREBONE...
A LINE OF VERY HEAVY THUNDERSTORMS FORMED OVER SOUTH LOUISIANA.
INDIVIDUAL THUNDERSTORMS..WITHIN THIS LINE..ARE MOVING NORTHWARD
ONE BEHIND THE OTHER LIKE A TRAIN. SIX INCHES OF RAINFALL HAS BEEN
REPORTED AT NAPOLEONVILLE IN ASSUMPTION PARISH WITHIN A 90 MINUTE
PERIOD. RADAR INDICATES THAT THESE THUNDERSTORMS ARE REFORMING OVER THE
SAME AREA. ADDITIONAL HEAVY RAINFALL WILL OCCUR AND COULD CAUSE
FLOODING IN LOW LYING AREAS AND ROADS.
<
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP 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, May 25, 2:59 PM CDT, 2 hours 9 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 255 PM CDT MON MAY 25 1987 ...STRONG THUNDERSTORMS WITH VERY HEAVY RAIN MOVING THROUGH BATON ROUGE... RADAR SHOWED STRONG THUNDERSTORMS WITH VERY HEAVY RAIN MOVING THROUGH THE BATON ROUGE METROPOLITAN AREA. THESE THUNDERSTORMS WERE MOVING NORTH ABOUT 15 MPH. PEOPLE THROUGHOUT THE BATON ROUGE METROPOLITAN AREA CAN EXPECT FLOODING OF STREETS AND LOW LYING AREAS...STRONG GUSTY WINND AND POSSIBLY HAIL AS THESE THUNDERSTORMS PASS THROUGH DURING THE NEXT 1 TO 2 HOURS. PEOPLE SHOULD USE CAUTION WHEN TRAVELING THROUGH FLOODED AREAS.
Special weather statement, May 25, 3:45 PM CDT, 1 hour 23 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 335 PM CDT MON MAY 25 1987 A LINE OF STRONG THUNDERSTORMS WITH HEAVY RAINS HAD DEVELOPED OVER SOUTHWEST MISSISSIPPI FROM CRYSTAL SPRINGS SOUTHWEST OF MCCOMB INTO LOUISIANA. THE LINE EXTENDED SOUTH BETWEEN BATON ROUGE AND THIBODAUX TO THE COAST NEAR MORGAN CITY. STRONG GUSTY WINDS...FREQUENT LIGHTNING AND SMALL HAIL MAY ACCOMPANY THIS LINE AS THE THUNDERSTORMS MOVE NORTH AT 15 MILES AN HOUR. PEOPLE SHOULD BE ESPECIALLY ALERT TO LOCAL STREET FLOODING IN THE HEAVY RAINS. ELSEWHERE...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS CONTINUED OVER SOUTHEAST LOUISIANA AND SOUTHWEST MISSISSIPPI. THE HEAVIEST AmCTIVITY HAD MOVED WEST OF THE NEW ORLEANS AREA.
Special weather statement, May 25, 4:46 PM CDT, 22 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE BATON ROUGE LA 445 PM CDT MON MAY 25 1987 ...STRONG THUNDERSTORMS WITH VERY HEAVY RAIN WERE MOVING ACROSS ST. LANDRY PARISH IN EAST CENTRAL LOUISIANA... RADAR SHOWED A CLUSTER OF STRONG THUNDERSTORMS WITH VERY HEAVY RAIN FROM NEAR LAFAYETTE TO EUNICE LOUISIANA. MOVEMENT WAS NORTH ABOUT 15 MPH. PEOPLE IN ST. LANDRY PARISH CAN EXPECT STRONG GUSTY WIND AND POSSIBLE HAIL...AND SOME STREET FLOODING FROM THE VERY HEAVY RAIN AS THESE STRONG THUNDERSTORMS PASS THROUGH DURING THE NEXT 1 TO 2 HOURS.
Special weather statement, May 25, 4:54 PM CDT, 14 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE NEW ORLEANS LA 450 PM CDT MON MAY 25 1987 A LINE OF STRONG THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED OVER SOUTHEAST LOUISIANA FROM DONALDSONVILLE SOUTH ACROSS THE MORGAN CITY AND HOUMA AREAS TO THE COAST. THIS LINE SHOWED LITTLE MOVEMENT DURING THE LAST HOUR AND FLOODING OF STREETS AND LOW LYING AREAS IS LIKELY. ELSEWHERE...THIS LINE OF THUNDERSTORMS EXTENDED NORTH ACROSS ACROSS BATON ROUGE INTO SOUTHWEST MISSISSIPPI BETWEEN NATCHEZ AND MCCOMB AND CONTINUE NORTH TO WEST OF JACKSON. OTHER THUNDERSTORMS WERE WIDELY SCATTERED ACROSS SOUTH LOUISIANA... SOUTH MISSISSIPPI...AND SOUTHWEST ALABAMA.
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 25, 5:08 PM CDT | Flash Flood Warning | LIX | Assumption, St. Mary, Terrebonne | 4 hr |
Nearby
Flash Flood Warnings in Louisiana, 1987Every flash flood warning in 1987
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.