Alert archive / Iowa / Special Weather Statements in 2021

Special Weather Statement, NWS La Crosse, WI

August 8, 2021Howard County, Iowa

NWS La Crosse, WI issued this special weather statement at Aug 8, 2021, 3:41 AM CDT for Howard County, Iowa. It was in force for 34 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
Aug 8, 2021, 3:41 AM CDT (08:41 UTC)
Expired
Aug 8, 2021, 4:15 AM CDT
In force
34 min
Issued by
NWS La Crosse, WI
Hail
0.25 in
Wind
40

County Howard County, IA

The radar

The La Crosse radar (KARX), 103 km from the middle of the area, began a volume at 08:41 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 8.7 hours before the alert went out and 177 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 00:00Z on 2021-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1238 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2021-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 144 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
1238 J/kg
Mixed-layer CIN
-150 J/kg
Mixed-layer LCL
630 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
144 m²/s²
0-3 km storm-relative helicity
226 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.6

Open this sounding in Storm Lab

The text

As transmitted.

969 
WWUS83 KARX 080841
SPSARX

Special Weather Statement
National Weather Service La Crosse WI
341 AM CDT Sun Aug 8 2021
 
IAZ009-MNZ095-080915-
Howard IA-Fillmore MN-
341 AM CDT Sun Aug 8 2021

...A strong thunderstorm will impact portions of northwestern Howard
and southwestern Fillmore Counties through 415 AM CDT...

At 341 AM CDT, Doppler radar was tracking a strong thunderstorm near
Lime Springs, or 14 miles northwest of Cresco, moving north at 25
mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Lime Springs, Cherry Grove, Bristol, York, Ostrander, Chester, Etna,
Greenleafton and Hayden Prairie.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4350 9246 4350 9245 4358 9245 4367 9244
      4357 9211 4338 9233 4344 9247
TIME...MOT...LOC 0841Z 200DEG 20KT 4346 9238 

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

$$

Kurz

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 7:16 PM CDTAreal Flood WarningARXVernon6 hr
Aug 7, 8:59 PM CDTRiver Flood WarningARXCrawford5 days
Aug 7, 8:59 PM CDTRiver Flood WarningARXCrawford6 days
Aug 7, 8:59 PM CDTRiver Flood WarningARXCrawford6 days
Aug 7, 9:14 PM CDTRiver Flood WarningARXJackson48 hr
Aug 8, 2:27 PM CDTSpecial Weather StatementARXAdams, Jackson, Juneau, Monroe78 min
Aug 8, 3:32 PM CDTSevere Thunderstorm WarningARXAdams31 min
Aug 8, 2:56 AM CDTSpecial Weather StatementARXHoward34 min

Nearby

Special Weather Statements in Iowa, 2021Every special weather statement in 2021

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.