Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 92, NWS La Crosse, WI

June 26, 2002Clayton County, Iowa

NWS La Crosse, WI issued this severe thunderstorm warning at Jun 26, 2002, 3:36 PM CDT for Clayton County, Iowa. It was in force for 24 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
Jun 26, 2002, 3:36 PM CDT (20:36 UTC)
Expired
Jun 26, 2002, 4:00 PM CDT
In force
24 min
Issued by
NWS La Crosse, WI
Area
Counties, with a storm outline in the text

County Clayton County, IA

The radar

The La Crosse radar (KARX), 114 km from the middle of the area, began a volume at 20:37 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

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

Minneapolis, MN (KMPX), launched 12:00Z, 8.6 hours before the alert went out and 286 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2002-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1160 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2002-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1160 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1198 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 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.

000 
WUUS53 KARX 262036
SVRLSE
IAC043-262100-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
ISSUED BY NWS DES MOINES IA
336 PM CDT WED JUN 26 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CLAYTON COUNTY IN NORTHEAST IOWA

* UNTIL 400 PM CDT

* AT 332 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER ELKADER...OR ABOUT 47 MILES NORTHWEST OF
  DUBUQUE...MOVING SOUTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE...

  6 MILES NORTHEAST OF LITTLEPORT AROUND 350 PM...
  NEAR GARNAVILLO AROUND 355 PM AND
  4 MILES NORTHEAST OF GARBER AROUND 400 PM.

HAIL UP TO THE SIZE OF NICKELS IS LIKELY IN THE WARNED AREA.

DAMAGING WINDS OF 60 TO 70 MILES AN HOUR ARE LIKELY IN THE WARNED
AREA.

MOVE TO AN INTERIOR ROOM AND STAY AWAY FROM WINDOWS. IF YOU LIVE IN A
MOBILE HOME...SEEK SHELTER IN A STURDY BUILDING.

LAT...LON 4290 9161 4267 9160 4267 9113 4292 9113

BOKSA

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 La Crosse, WI wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 26, 2:57 PM CDT, 39 minutes earlier.

Area forecast discussion, Jun 26, 2:57 PM CDT, 39 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LA CROSSE WI
257 PM CDT WED JUN 26 2002

NEXT FEW HOURS WILL BE MAIN FORECAST CHALLENGE AS THUNDERSTORMS HAVE
DEVELOPED IN NARROW WEDGE OF INSTABILITY OVER NERN IA INTO WI.
OUTFLOW FROM THE COMPLEX OF STORMS IN SE IA MERGED WITH THE COLD
FRONT OVER THE AREA PRODUCING RAPID DEVELOPMENT. STRONGER STORMS ARE
EXPECTED TO CONTINUE DEVELOPING S/SSW INTO STRONGER INSTABILITY.
HOWEVER SCATTERED STORMS SHOULD CONTINUE SE FROM CURRENT LOCATION
INTO THE EARLY EVENING HOURS...AND NEWD ALG THE FNT INTO WI.

AFTER THAT...QUIET WEATHER IS EXPECTED FOR NEXT FEW DAYS...ALTHOUGH
THERE ARE SOME QUESTION MARKS.  HI PRESSURE BUILDS IN TONIGHT
ACCOMPANIED BY THERMAL TROUGH ALOFT INTO THU. PREFER THE LOOK OF ETA
FIELDS ON THU...WITH AVN MUCH STRONGER IN DEVELOPING A SFC
TROUGH...LOW LEVEL WARM ADVECTION AND PCPN THAT LOOKS A BIT
OVERDONE. CANNOT RULE OUT SOME AFTERNOON SHOWERS OR THUNDERSTORMS
ESPECIALLY OVER CENTRAL WI...BUT AT THIS TIME A CONTINUATION OF DRY
FORECAST LOOKS BEST. SEE NO REASON TO ALTER GOING TEMP FORECAST FOR
NEXT FEW DAYS.

HI PRES ALOFT PASSES EAST OF THE MS RIVER SOMETIME ON SUNDAY...
LEAVING FORECAST AREA ON SOUTHERN FRINGE OF FAIRLY WEAK WESTERLIES
ALOFT. FORECAST OF THUNDER BECOMES PROBLEMATIC SINCE TIMING AND
NORTH/SOUTH EXTENT OF SHORTWAVES IS IN DOUBT. RIDGE-RUNNER
CONVECTION MAY CLIP THE UPPER MIDWEST THROUGHOUT THE EXTENDED BUT
POPS LIKELY TO BE LOW. 12Z AVN IS A BIT FARTHER NORTH THAN 00Z MRF
WITH SUNDAY MORNING SHORTWAVE...SO WL LEAVE CHANCES IN NORTHERN HALF
OF FORECAST AREA. WL CONTINUE WITH CHANCES MON AND TUE...DRY ON WED
FOR NOW AS WK SFC HIGH BUILDS ACROSS TO THE NORTH.

.LSE...NONE.

JUNGBLUTH

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 26, 1:09 PM CDTTornado WarningARXWinneshiek36 min
Jun 26, 1:47 PM CDTSevere Thunderstorm WarningARXWinneshiek43 min
Jun 26, 2:33 PM CDTTornado WarningARXFayette27 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2002Every 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; radar from the NEXRAD Level II archive.