Alert archive / Iowa / Heat Advisories in 2021

Heat Advisory 2, NWS La Crosse, WI

August 9, 2021Crawford County, Grant County, Richland County, Wisconsin; 6 counties in Iowa

NWS La Crosse, WI issued this heat advisory at Aug 9, 2021, 1:55 PM CDT for Crawford County, Grant County, Richland County, Wisconsin; 6 counties in Iowa. It took effect at Aug 10, 2021, 12:00 PM CDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Aug 9, 2021, 1:55 PM CDT (18:55 UTC)
In effect from
Aug 10, 2021, 12:00 PM CDT
Expired
Aug 10, 2021, 5:40 PM CDT
In force
6 hr
Issued by
NWS La Crosse, WI

Counties Allamakee County, IA, Chickasaw County, IA, Clayton County, IA, Fayette County, IA, Floyd County, IA, Winneshiek County, IA, Crawford County, WI, Grant County, WI, Richland County, WI

The radar

The La Crosse radar (KARX), 85 km from the middle of the area, began a volume at 18:58 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

Davenport, (KDVN), launched 12:00Z, 6.9 hours before the alert went out and 184 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, Davenport, at 12:00Z on 2021-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1676 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, Davenport, at 12:00Z on 2021-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 171 square meters per square second.193958Sfc1 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
1676 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
705 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
171 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.7

Open this sounding in Storm Lab

The text

As transmitted.

051 
WWUS73 KARX 091855
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
155 PM CDT Mon Aug 9 2021

IAZ010-011-018-019-029-030-WIZ054-055-061-100300-
/O.NEW.KARX.HT.Y.0002.210810T1700Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Clayton-Crawford-
Richland-Grant-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Elkader, Prairie Du Chien, Richland Center,
and Platteville
155 PM CDT Mon Aug 9 2021

...HEAT ADVISORY IN EFFECT FROM NOON TO 7 PM CDT TUESDAY...

* WHAT...Heat index values up to 104 expected.

* WHERE...In Wisconsin, Crawford, Richland and Grant Counties. 
  In Iowa, Winneshiek, Allamakee, Floyd, Chickasaw, Fayette and 
  Clayton Counties.

* WHEN...From noon to 7 PM CDT Tuesday.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...There is some uncertainty in this
  temperature forecast, especially given the potential for
  thunderstorms to move through during the morning hours. Stay
  tuned for the latest information.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

KDS
5 follow-up statements
068 
WWUS73 KARX 100135
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
835 PM CDT Mon Aug 9 2021

IAZ010-011-018-019-029-030-WIZ054-055-061-101000-
/O.CON.KARX.HT.Y.0002.210810T1700Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Clayton-Crawford-
Richland-Grant-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Elkader, Prairie Du Chien, Richland Center,
and Platteville
835 PM CDT Mon Aug 9 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TO 7 PM CDT
TUESDAY...

* WHAT...Heat index values up to 104 expected.

* WHERE...In Wisconsin, Crawford, Richland and Grant Counties. 
  In Iowa, Winneshiek, Allamakee, Floyd, Chickasaw, Fayette and 
  Clayton Counties. 

* WHEN...From noon to 7 PM CDT Tuesday.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur. 

* ADDITIONAL DETAILS...There is some uncertainty in this 
  temperature forecast, especially given the potential for 
  thunderstorms to move through during the morning hours. Stay 
  tuned for the latest information. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
023 
WWUS73 KARX 100850
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
350 AM CDT Tue Aug 10 2021

IAZ010-011-018-019-029-030-WIZ054-055-061-101700-
/O.CON.KARX.HT.Y.0002.210810T1700Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Clayton-Crawford-
Richland-Grant-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Elkader, Prairie Du Chien, Richland Center,
and Platteville
350 AM CDT Tue Aug 10 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO 7 PM CDT
THIS EVENING...

* WHAT...Heat index values up to 104 expected.

* WHERE...In Wisconsin, Crawford, Richland and Grant Counties. 
  In Iowa, Winneshiek, Allamakee, Floyd, Chickasaw, Fayette and 
  Clayton Counties.

* WHEN...From noon to 7 PM CDT Today.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

* ADDITIONAL DETAILS...There is some uncertainty in this
  temperature forecast, especially given the potential for clouds
  and thunderstorms today.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
559 
WWUS73 KARX 101751
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
1251 PM CDT Tue Aug 10 2021

IAZ010-011-018-019-029-030-WIZ054-055-061-110000-
/O.CON.KARX.HT.Y.0002.000000T0000Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Clayton-Crawford-
Richland-Grant-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Elkader, Prairie Du Chien, Richland Center,
and Platteville
1251 PM CDT Tue Aug 10 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...

* WHAT...Heat index values up to 106.

* WHERE...In Wisconsin, Grant, Richland and Crawford Counties. 
  In Iowa, Chickasaw, Floyd, Clayton, Allamakee, Winneshiek and 
  Fayette Counties.

* WHEN...Until 7 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

KDS
214 
WWUS73 KARX 101926
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
226 PM CDT Tue Aug 10 2021

IAZ030-WIZ061-110600-
/O.NEW.KARX.HT.Y.0003.210811T1700Z-210811T2200Z/
/O.CON.KARX.HT.Y.0002.000000T0000Z-210811T0000Z/
Clayton-Grant-
Including the cities of Elkader and Platteville
226 PM CDT Tue Aug 10 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM NOON TO 5 PM CDT WEDNESDAY...

* WHAT...For the first Heat Advisory, heat index values up to 
  107. For the second Heat Advisory, heat index values up to 101 
  expected.

* WHERE...In Wisconsin, Grant County. In Iowa, Clayton County.

* WHEN...For the first Heat Advisory, until 7 PM CDT this 
  evening. For the second Heat Advisory, from noon to 5 PM CDT 
  Wednesday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

IAZ010-011-018-019-029-WIZ054-055-110000-
/O.CON.KARX.HT.Y.0002.000000T0000Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Crawford-Richland-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Prairie Du Chien, and Richland Center
226 PM CDT Tue Aug 10 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...

* WHAT...Heat index values up to 105.

* WHERE...In Wisconsin, Richland and Crawford Counties. In Iowa, 
  Chickasaw, Floyd, Allamakee, Winneshiek and Fayette Counties.

* WHEN...Until 7 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
819 
WWUS73 KARX 102240
NPWARX

URGENT - WEATHER MESSAGE
National Weather Service La Crosse WI
540 PM CDT Tue Aug 10 2021

IAZ030-WIZ061-110645-
/O.CAN.KARX.HT.Y.0002.000000T0000Z-210811T0000Z/
/O.CON.KARX.HT.Y.0003.210811T1700Z-210811T2200Z/
Clayton-Grant-
Including the cities of Elkader and Platteville
540 PM CDT Tue Aug 10 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TO 5 PM CDT
WEDNESDAY...
...HEAT ADVISORY IS CANCELLED...

* WHAT...The Heat Advisory for today has been cancelled due to the
  storms in the area cooling temperatures down below heat advisory
  criteria. For the second Heat Advisory Wednesday, heat index 
  values up to 101 are expected.

* WHERE...In Iowa, Clayton County. In Wisconsin, Grant County.

* WHEN...From noon to 5 PM CDT Wednesday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

IAZ010-011-018-019-029-WIZ054-055-102345-
/O.CAN.KARX.HT.Y.0002.000000T0000Z-210811T0000Z/
Winneshiek-Allamakee-Floyd-Chickasaw-Fayette-Crawford-Richland-
Including the cities of Decorah, Waukon, Charles City, 
New Hampton, Oelwein, Prairie Du Chien, and Richland Center
540 PM CDT Tue Aug 10 2021

...HEAT ADVISORY IS CANCELLED...

The Heat Advisory for today has been cancelled due to the storms 
in the area cooling temperatures down below heat advisory
criteria.

$$

Zapotocny

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 8, 9:11 PM CDTRiver Flood WatchARXLa Crosse, Trempealeau48 hr
Aug 9, 9:17 AM CDTRiver Flood WatchARXJuneau36 hr
Aug 8, 9:50 PM CDTSpecial Weather StatementARXAllamakee, Chickasaw, Clayton, Fayette, Howard, Winneshiek55 min
Aug 9, 12:10 AM CDTFlash Flood WarningARXChickasaw, Floyd6 hr

Nearby

Heat Advisories in Iowa, 2021Heat Advisories in Wisconsin, 2021Every heat advisory 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.