Alert archive / Louisiana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 66, NWS New Orleans, LA

July 19, 2002Washington Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 19, 2002, 5:22 PM CDT for Washington Parish, Louisiana. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 19, 2002, 5:22 PM CDT (22:22 UTC)
Expired: Jul 19, 2002, 6:00 PM CDT
In force: 38 min
Issued by: NWS New Orleans, LA
Area: Counties, with a storm outline in the text

County Washington Parish, LA

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 10.4 hours before the alert went out and 58 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 2104 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 1111 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

378 
WUUS54 KLIX 192222
SVRNEW
LAC117-192300-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NEW ORLEANS LA
521 PM CDT FRI JUL 19 2002

THE NATIONAL WEATHER SERVICE IN NEW ORLEANS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WASHINGTON PARISH IN SOUTHEAST LOUISIANA

* UNTIL 600 PM CDT

* AT 520 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A   
SEVERE THUNDERSTORM OVER WASHINGTON PARISH...OR ABOUT 5 MILES   
SOUTHWEST OF BOGALUSA...MOVING NORTHWEST AT 20 MPH.

THIS IS A DANGEROUS STORM WITH DAMAGING WINDS...DIME SIZE HAIL AND 
HEAVY RAINFALL...STAY INDOORS AWAY FROM WINDOWS.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE.

LAT...LON 3066 8990 3066 8983 3085 8998 3080 9010

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.

NWS New Orleans, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 19, 2:30 PM CDT, 2 hours 52 minutes earlier.

Area forecast discussion, Jul 19, 2:30 PM CDT, 2 hours 52 minutes before

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE NEW ORLEANS/BATON ROUGE LA
230 PM CDT FRI JUL 19 2002

HAND UPPER AIR ANALYSIS CONTINUE TO SHOW A THERMAL TROUGH AT 500MB
MAINLY ALONG THE MID AND LOWER MISSISSIPPI VALLEY. MOST OF
LOUISIANA...ARKANSAS AND MISSISSIPPI 500MB TEMPERATURES WERE AROUND
-9 AT 12Z THIS MORNING. THIS COOL AIR WAS JUST AHEAD OF A SHORT WAVE
FROM WEST KENTUCKY TO NORTH TEXAS. CYCLONIC CIRCULATION AT 200MB WAS
NOTED OVER NORTHEAST ARKANSAS AND ANTICYCLONIC CIRCULATION AT 200MB
JUST SOUTH OF LAKE CHARLES FORECAST AREA AT 12Z THIS MORNING.
PRECIPITABLE WATER VALUES OFF OF SLIDELL SOUNDINGS INDICATED A
DECREASE FROM 2.2 INCHES THURSDAY MORNING TO 1.8 INCHES. IN
ADDITION...PW PLOTS REVEALED POCKETS OF DRY AIR WITH 1.5 INCHES OR
LESS OVER SOUTHWEST LOUISIANA/NORTHWEST GULF AND OVER GEORGIA. NO
REAL INVERSIONS THROUGHOUT THE COLUMN...EXCEPT JUST ABOVE 500MB TO
450MB.

SHORT RANGE MODELS ARE IN GOOD AGREEMENT. SHORT WAVE MOVE EAST
ACROSS THE TENNESSEE VALLEY TO THE APPALACHIAN BY SATURDAY MORNING.
SOUTHWEST FLOW WILL ADVECT DRY AIR FROM THE SOUTHWEST TO OUR
FORECAST AREA SATURDAY...THUS DROPPING PWS LESS 1.5 INCHES FOR WEST
HALF OF FORECAST SAT AND DECREASING POPS TO NIL...ISOLATED FOR
COAST. THIS TREND SHOULD CONTINUE THROUGH SUNDAY WITH THE WEST HALF
WITH ZERO POPS AND EAST HALF AROUND 10 PERCENT. SURFACE RIDGE AXIS
WILL REMAIN ACROSS THE EAST HALF OF THE GULF PRODUCING A SOUTHWEST
FLOW. UPPER LEVEL RIDGE AMPLIFIES OVER THE WEST CONUS...RESULTING IN
A NORTHWEST FLOW OVER SOUTHEAST CONUS AND MOISTURE AXIS JUST
NORTHEAST OF THE FORECAST AREA. A SHORT WAVE ON THE TOP OF THE RIDGE
OUT WEST WILL MOVE EAST ACROSS THE GREAT LAKES...THUS TIGHTENING THE
MOISTURE AXIS OVER THE MID SOUTH WED AND THU. THE ASSOCIATED
BOUNDARY WITH THE MID WEEK SHORT WAVE WILL BECOME STATIONARY AND
LIFT NORTH. WILL CONTINUE TO SLIGHT CHANCE MON THROUGH FRI WITH
TEMPS IN THE 90 TO 95 DEGREE RANGE.

HEAT ADVISORY WILL REMAIN IN EFFECT THROUGH SATURDAY. 500 TO 1000MB
THICKNESS DO NOT CHANGE ANY OVER THE WEEKEND. HOWEVER...1000 TO
700MB THICKNESS CHANGE FROM 3080M TO 3075M. DRY AIR AND CLOSE TO NIL
POPS SHOULD OFFSET FIVE METERS SATURDAY WITH ALL DAY HEATING.

PRELIMINARY NUMBERS FOLLOW...

MCB 74/96/74/95 0011       BTR 75/96/76/95 0011
MSY 78/95/77/94 0011       GPT 75/96/75/95 0111

.NEW...NONE
LA...HEAT ADVISORY LAZ058>070.
MS...NONE.

18

In the hours before

Local storm report, Jul 19, 5:10 PM CDT, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW ORLEANS, LA
510 PM CDT FRI JUL 19 2002

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

0330 PM    SLIDELL EAST              LA   WIND DAMAGE
07/19/02   ST TAMMANY                     TWO PINE TREES BLOWN DOWN
                                          ON POWERLINES. DIME SIZE
                                          HAIL AT CROSS GATES SUB-
                                          DIVISION. REPORTED BY OFF
                                          DUTY NWS METEOROLOGIST.

0440 PM    FRENCH QUARTER            LA   HAIL
07/19/02   ORLEANS                        PUBLIC REPORTED PEA TO
                                          MARBLE SIZE HAIL AND
                                          STREET FLOODING.

The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 19, 4:37 PM CDT	Severe Thunderstorm Warning	LIX	Saint Tammany, Washington	53 min
Jul 19, 4:46 PM CDT	Severe Thunderstorm Warning	LIX	Jefferson, Orleans	59 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2002 Every severe thunderstorm warning in 2002

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.