Alert archive / Iowa / Heat Advisories in 2021

Heat Advisory 2, NWS Des Moines, IA

July 23, 202116 counties in Iowa

NWS Des Moines, IA issued this heat advisory at Jul 23, 2021, 3:17 AM CDT for 16 counties in Iowa. It took effect at Jul 24, 2021, 12:00 PM CDT. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
Jul 23, 2021, 3:17 AM CDT (08:17 UTC)
In effect from
Jul 24, 2021, 12:00 PM CDT
Expired
Jul 24, 2021, 8:00 PM CDT
In force
8 hr
Issued by
NWS Des Moines, IA

Counties Adams County, IA, Appanoose County, IA, Clarke County, IA, Davis County, IA, Decatur County, IA, Lucas County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Poweshiek County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA

The radar

The Des Moines radar (KDMX), 83 km from the middle of the area, began a volume at 08:20 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

Omaha, NE (KOAX), launched 00:00Z, 8.3 hours before the alert went out and 250 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, Omaha, NE at 00:00Z on 2021-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 23 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, Omaha, NE at 00:00Z on 2021-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
23 J/kg
Mixed-layer CIN
-234 J/kg
Mixed-layer LCL
1577 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
150 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

561 
WWUS73 KDMX 230817
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
317 AM CDT Fri Jul 23 2021

IAZ062-073>075-081>086-092>097-231630-
/O.NEW.KDMX.HT.Y.0002.210724T1700Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
317 AM CDT Fri Jul 23 2021

...HEAT ADVISORY IN EFFECT FROM NOON TO 8 PM CDT SATURDAY...

* WHAT...High temperatures in the mid 90s with heat index values 
  up to 105 expected.

* WHERE...Parts of southern and east central Iowa.

* WHEN...From Noon to 8 PM CDT Saturday.

* 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.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines
5 follow-up statements
653 
WWUS73 KDMX 231537
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
1037 AM CDT Fri Jul 23 2021

IAZ062-073>075-081>086-092>097-232345-
/O.CON.KDMX.HT.Y.0002.210724T1700Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
1037 AM CDT Fri Jul 23 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TO 8 PM CDT
SATURDAY...

* WHAT...High temperatures in the mid 90s with heat index values 
  up to 105 expected.

* WHERE...Parts of southern and east central Iowa.

* WHEN...From Noon to 8 PM CDT Saturday.

* 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.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

Hagenhoff
898 
WWUS73 KDMX 240027
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
727 PM CDT Fri Jul 23 2021

IAZ062-073>075-081>086-092>097-240830-
/O.CON.KDMX.HT.Y.0002.210724T1700Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
727 PM CDT Fri Jul 23 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TO 8 PM CDT
SATURDAY...

* WHAT...High temperatures in the mid 90s with heat index values 
  up to 105 expected.

* WHERE...Parts of southern and east central Iowa.

* WHEN...From Noon to 8 PM CDT Saturday.

* 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.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines
606 
WWUS73 KDMX 241308
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
808 AM CDT Sat Jul 24 2021

IAZ062-073>075-081>086-092>097-241800-
/O.CON.KDMX.HT.Y.0002.210724T1700Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
808 AM CDT Sat Jul 24 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM NOON TODAY TO 8 PM CDT
THIS EVENING...

* WHAT...High temperatures in the lower to middle 90s with heat 
  index values up to 105 expected.

* WHERE...Parts of southern and east central Iowa.

* WHEN...From Noon to 8 PM CDT Saturday.

* 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.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

Small
558 
WWUS73 KDMX 241848
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
148 PM CDT Sat Jul 24 2021

IAZ062-073>075-081>086-092>097-250100-
/O.CON.KDMX.HT.Y.0002.000000T0000Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
148 PM CDT Sat Jul 24 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING...

* WHAT...High temperatures in the lower to middle 90s with heat 
  index values up to 105 expected.

* WHERE...Parts of southern and east central Iowa.

* WHEN...Through 8 PM CDT today.

* 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.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines
512 
WWUS73 KDMX 250113
NPWDMX

URGENT - WEATHER MESSAGE
National Weather Service Des Moines IA
813 PM CDT Sat Jul 24 2021

IAZ062-073>075-081>086-092>097-250215-
/O.EXP.KDMX.HT.Y.0002.000000T0000Z-210725T0100Z/
Poweshiek-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-
Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
Including the cities of Grinnell, Indianola, Norwalk, Carlisle, 
Pella, Knoxville, Oskaloosa, Corning, Creston, Osceola, Chariton,
Albia, Ottumwa, Bedford, Lenox, New Market, Mount Ayr, Lamoni, 
Leon, Corydon, Seymour, Allerton, Humeston, Centerville, 
and Bloomfield
813 PM CDT Sat Jul 24 2021

...HEAT ADVISORY HAS EXPIRED...

Heat index values have fallen below advisory levels. However, very
hot weather will persist through the middle of next week, and
additional headlines may become necessary.

$$

For more information from the National Weather Service visit
https://weather.gov/desmoines

Nearby

Heat Advisories in Iowa, 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.