Alert archive / Minnesota / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 93, NWS La Crosse, WI

August 9, 1999Houston County, Minnesota

NWS La Crosse, WI issued this severe thunderstorm warning at Aug 9, 1999, 2:36 PM CDT for Houston County, Minnesota. It was in force for 54 min. 1 report 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
Aug 9, 1999, 2:36 PM CDT (19:36 UTC)
Expired
Aug 9, 1999, 3:30 PM CDT
In force
54 min
Issued by
NWS La Crosse, WI
Area
Whole counties

County Houston County, MN

The radar

The La Crosse radar (KARX), 30 km from the middle of the area, began a volume at 19:38 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.

What was reported inside it

TimeReportWhereRemark
Aug 9, 2:50 PM CDTHail 0.75Houston, MN

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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 7.6 hours before the alert went out and 213 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 1999-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 1999-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1057 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
199 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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.

NWS La Crosse, WI wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 2:08 PM CDT, 28 minutes earlier.

Area forecast discussion, Aug 9, 2:08 PM CDT, 28 minutes before
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In the hours before

Special weather statement, Aug 9, 11:45 AM CDT, 2 hours 51 minutes before
IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-101200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LA CROSSE WI
1145 AM CDT MON AUG 9 1999

...A MODERATE RISK FOR SEVERE WEATHER ACROSS MUCH OF THE AREA LATER
THIS AFTERNOON AND THIS EVENING...

THE STORM PREDICTION CENTER HAS INDICATED THERE IS A MODERATE RISK OF
SEVERE WEATHER ALONG AND NORTH OF AN AUSTIN MINNESOTA...TO DECORAH
IOWA...TO RICHLAND CENTER WISCONSIN LINE. SOUTH OF THIS LINE THERE IS
A SLIGHT RISK FOR SEVERE WEATHER...IN NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN.

LATE THIS MORNING A COLD FRONT WAS LOCATED IN THE EASTERN DAKOTAS...
WHILE A WARM FRONT STRETCHED FROM NEAR SIOUX FALLS SD TO NEAR WATERLOO
IOWA.  THE WARM FRONT IS EXPECTED TO LIFT NORTH THIS AFTERNOON...WITH A
MOIST AND UNSTABLE AIRMASS SPREADING ACROSS THE AREA.  THE COLD FRONT
WILL PUSH ACROSS MINNESOTA THIS AFTERNOON AND EVENING...AND ACROSS
WISCONSIN TONIGHT.

AS THE COLD FRONT SLICES INTO THE UNSTABLE AIRMASS...MORE THUNDERSTORMS
ARE EXPECTED TO DEVELOP IN WESTERN MINNESOTA THIS AFTERNOON...THEN PUSH
EAST ACROSS THE AREA DURING THE LATE AFTERNOON AND EVENING HOURS. THE
LOWER AND MIDDLE LEVEL WIND PROFILE IN THE ATMOSPHERE WILL BE FAVORABLE
FOR ORGANIZED STORMS AND SUPERCELLS. THE SEVERE WEATHER THREATS WILL BE
DAMAGING WINDS...LARGE HAIL AND ISOLATED TORNADOES.

STORM SPOTTER GROUPS SHOULD REMAIN ALERT...AS ACTIVATION IS A GOOD BET
LATE THIS AFTERNOON AND EVENING...ROUGHLY BETWEEN THE HOURS OF 5 PM AND
MIDNIGHT. STAY TUNED TO YOUR FAVORITE SOURCE OF WEATHER INFORMATION
FOR LATER UPDATES ON THIS THREAT FOR SEVERE WEATHER.

RRS
Special weather statement, Aug 9, 11:45 AM CDT, 2 hours 51 minutes before
IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029-
032>034-041>044-053>055-061-101200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LA CROSSE WI
1145 AM CDT MON AUG 9 1999

...A MODERATE RISK FOR SEVERE WEATHER ACROSS MUCH OF THE AREA LATER
THIS AFTERNOON AND THIS EVENING...

THE STORM PREDICTION CENTER HAS INDICATED THERE IS A MODERATE RISK OF
SEVERE WEATHER ALONG AND NORTH OF AN AUSTIN MINNESOTA...TO DECORAH
IOWA...TO RICHLAND CENTER WISCONSIN LINE. SOUTH OF THIS LINE THERE IS
A SLIGHT RISK FOR SEVERE WEATHER...IN NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN.

LATE THIS MORNING A COLD FRONT WAS LOCATED IN THE EASTERN DAKOTAS...
WHILE A WARM FRONT STRETCHED FROM NEAR SIOUX FALLS SD TO NEAR WATERLOO
IOWA.  THE WARM FRONT IS EXPECTED TO LIFT NORTH THIS AFTERNOON...WITH A
MOIST AND UNSTABLE AIRMASS SPREADING ACROSS THE AREA.  THE COLD FRONT
WILL PUSH ACROSS MINNESOTA THIS AFTERNOON AND EVENING...AND ACROSS
WISCONSIN TONIGHT.

AS THE COLD FRONT SLICES INTO THE UNSTABLE AIRMASS...MORE THUNDERSTORMS
ARE EXPECTED TO DEVELOP IN WESTERN MINNESOTA THIS AFTERNOON...THEN PUSH
EAST ACROSS THE AREA DURING THE LATE AFTERNOON AND EVENING HOURS. THE
LOWER AND MIDDLE LEVEL WIND PROFILE IN THE ATMOSPHERE WILL BE FAVORABLE
FOR ORGANIZED STORMS AND SUPERCELLS. THE SEVERE WEATHER THREATS WILL BE
DAMAGING WINDS...LARGE HAIL AND ISOLATED TORNADOES.

STORM SPOTTER GROUPS SHOULD REMAIN ALERT...AS ACTIVATION IS A GOOD BET
LATE THIS AFTERNOON AND EVENING...ROUGHLY BETWEEN THE HOURS OF 5 PM AND
MIDNIGHT. STAY TUNED TO YOUR FAVORITE SOURCE OF WEATHER INFORMATION
FOR LATER UPDATES ON THIS THREAT FOR SEVERE WEATHER.

RRS
Special weather statement, Aug 9, 12:15 PM CDT, 2 hours 21 minutes before
IAZ131-067-037-089-091800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1215 PM CDT MON AUG 9 1999

...THUNDERSTORMS MOVING ACROSS NORTHEAST IOWA...

AT 1210 PM...DOPPLER RADAR IN LA CROSSE WAS INDICATING SCATTERED
THUNDERSTORMS MOVING INTO NORTHEAST IOWA FROM SOUTHCENTRAL MINNESOTA AND
NORTHCENTRAL IOWA.  THESE STORMS CONTINUE TO PRODUCE HEAVY RAIN AND
LIGHTNING...AND ISOLATED REPORTS OF DIME-SIZED HAIL.  THE MASON CITY
AIRPORT RECEIVED ONE-HALF INCH DIAMETER HAIL AND CLEAR LAKE HAD
NICKEL-SIZED HAIL.  AT 1213 PM...DOPPLER RADAR INDICATED THIS
PARTICULAR STORM WAS WEAKENING AS IT MOVED TOWARD FLOYD COUNTY.

THE THUNDERSTORMS ARE MOVING SOUTHEAST AT 40 MPH AND WILL MOVE THROUGH
THE AREA BY 130 PM.  THE NATIONAL WEATHER SERVICE IN LA CROSSE IS
MONITORING THE THUNDERSTORMS AND WILL ISSUE FURTHER UPDATES AS NEEDED.
TAKE PRECAUTIONS NOW FOR THESE THUNDERSTORMS AND STAY TUNED TO YOUR
FAVORITE WEATHER SOURCE FOR UPDATES.

DB
Special weather statement, Aug 9, 12:15 PM CDT, 2 hours 21 minutes before
IAZ131-067-037-089-091800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
1215 PM CDT MON AUG 9 1999

...THUNDERSTORMS MOVING ACROSS NORTHEAST IOWA...

AT 1210 PM...DOPPLER RADAR IN LA CROSSE WAS INDICATING SCATTERED
THUNDERSTORMS MOVING INTO NORTHEAST IOWA FROM SOUTHCENTRAL MINNESOTA AND
NORTHCENTRAL IOWA.  THESE STORMS CONTINUE TO PRODUCE HEAVY RAIN AND
LIGHTNING...AND ISOLATED REPORTS OF DIME-SIZED HAIL.  THE MASON CITY
AIRPORT RECEIVED ONE-HALF INCH DIAMETER HAIL AND CLEAR LAKE HAD
NICKEL-SIZED HAIL.  AT 1213 PM...DOPPLER RADAR INDICATED THIS
PARTICULAR STORM WAS WEAKENING AS IT MOVED TOWARD FLOYD COUNTY.

THE THUNDERSTORMS ARE MOVING SOUTHEAST AT 40 MPH AND WILL MOVE THROUGH
THE AREA BY 130 PM.  THE NATIONAL WEATHER SERVICE IN LA CROSSE IS
MONITORING THE THUNDERSTORMS AND WILL ISSUE FURTHER UPDATES AS NEEDED.
TAKE PRECAUTIONS NOW FOR THESE THUNDERSTORMS AND STAY TUNED TO YOUR
FAVORITE WEATHER SOURCE FOR UPDATES.

DB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 1:23 PM CDTSevere Thunderstorm WarningARXOlmsted57 min
Aug 9, 1:39 PM CDTSevere Thunderstorm WarningARXFillmore61 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1999Every severe thunderstorm warning in 1999

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; radar from the NEXRAD Level II archive.