Alert archive / Iowa / Red Flag Warnings in 2021

Red Flag Warning 5, NWS Des Moines, IA

May 1, 202130 counties in Iowa

NWS Des Moines, IA issued this red flag warning at May 1, 2021, 3:57 AM CDT for 30 counties in Iowa. It took effect at May 1, 2021, 1:00 PM CDT. It was in force for 6 hr. 2 reports 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
May 1, 2021, 3:57 AM CDT (08:57 UTC)
In effect from
May 1, 2021, 1:00 PM CDT
Expired
May 1, 2021, 7:00 PM CDT
In force
6 hr
Issued by
NWS Des Moines, IA
All 30 counties

Adair County, IA, Audubon County, IA, Black Hawk County, IA, Boone County, IA, Bremer County, IA, Butler County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Crawford County, IA, Dallas County, IA, Emmet County, IA, Franklin County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Humboldt County, IA, Kossuth County, IA, Palo Alto County, IA, Pocahontas County, IA, Sac County, IA, Story County, IA, Webster County, IA, Winnebago County, IA, Worth County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 84 km from the middle of the area, began a volume at 08:54 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
May 1, 1:53 PM CDTNON-TSTM WND GST 593 S Ames, IAASOS STATION KAMW AMES AIRPORT.
May 1, 3:28 PM CDTNON-TSTM WND GST 62Grafton, IAMEASURED BY HOME WEATHER STATION. FROM KAAL/ABC6 VIEWER.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 9.0 hours before the alert went out and 235 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 2021-05-01Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2021-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2917 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
306 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

884 
WWUS83 KDMX 010857
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
357 AM CDT Sat May 1 2021

...Extreme Fire Danger in Portions of Central and Northern Iowa 
This Afternoon...

.Strong southwest winds, very warm temperatures, low relative 
humidity values along with mostly dry fuels will combine to 
produce extreme fire conditions in portions of central and northern
Iowa this afternoon. Elevated fire conditions are expected 
elsewhere in central and southern Iowa. 

IAZ004>007-015>017-023>026-033>037-044>047-011700-
/O.NEW.KDMX.FW.W.0005.210501T1800Z-210502T0000Z/
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Sac-Calhoun-Webster-Hamilton-
Hardin-Crawford-Carroll-Greene-Boone-
357 AM CDT Sat May 1 2021

...RED FLAG WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO 7 PM
CDT THIS EVENING FOR EXTREME FIRE CONDITIONS... 

The National Weather Service in Des Moines has issued a Red Flag 
Warning, which is in effect from 1 PM this afternoon to 7 PM CDT 
this evening. 

* AFFECTED AREA...Portions of central and northern Iowa.

* WIND...Southwest winds at 20 to 30 mph gusting up to 40 mph.

* HUMIDITY...Dropping to between 20 to 25 percent this afternoon.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.

&&

$$
3 follow-up statements
278 
WWUS83 KDMX 011502
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
1002 AM CDT Sat May 1 2021

...Extreme Fire Danger Northwest Half Of Iowa Today...

.Strong southwest winds, very warm temperatures, and low relative
humidity along with mostly dry fuels will combine to produce 
extreme fire conditions this afternoon. Elevated fire conditions 
are expected elsewhere across southern and eastern Iowa.

IAZ027-028-038-039-048-057>059-070-071-012315-
/O.EXA.KDMX.FW.W.0005.210501T1800Z-210502T0000Z/
Butler-Bremer-Grundy-Black Hawk-Story-Audubon-Guthrie-Dallas-Cass-
Adair-
1002 AM CDT Sat May 1 2021

...RED FLAG WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO 7 PM
CDT THIS EVENING FOR EXTREME FIRE CONDITIONS....

The National Weather Service in Des Moines has issued a Red Flag
Warning FOR EXTREME FIRE CONDITIONS, which is in effect from 1 PM
this afternoon to 7 PM CDT this evening.

* AFFECTED AREA...Portions of western, central and northern Iowa.

* WIND...Sustained southwest winds of 20 to 30 mph gusting up to 
  40 mph.

* HUMIDITY...Dropping to near 20 percent this afternoon.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.

&&

$$

IAZ004>007-015>017-023>026-033>037-044>047-012315-
/O.CON.KDMX.FW.W.0005.210501T1800Z-210502T0000Z/
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Sac-Calhoun-Webster-Hamilton-
Hardin-Crawford-Carroll-Greene-Boone-
1002 AM CDT Sat May 1 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM 1 PM THIS AFTERNOON TO
7 PM CDT THIS EVENING FOR EXTREME FIRE CONDITIONS...

* AFFECTED AREA...Portions of western, central and northern Iowa.

* WIND...Sustained southwest winds of 20 to 30 mph gusting up to 
  40 mph.

* HUMIDITY...Dropping to near 20 percent this afternoon.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.

&&

$$
869 
WWUS83 KDMX 011917
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
217 PM CDT Sat May 1 2021

...Extreme Fire Danger Northwest Half Of Iowa Today...

.Strong southwest winds, very warm temperatures, and low relative
humidity along with mostly dry fuels are combining to produce 
extreme fire conditions across northern and western, into central
Iowa this afternoon. Elevated fire conditions are expected 
elsewhere across southern and eastern Iowa.

IAZ004>007-015>017-023>028-033>039-044>048-057>059-070-071-020000-
/O.CON.KDMX.FW.W.0005.000000T0000Z-210502T0000Z/
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun-
Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-
Boone-Story-Audubon-Guthrie-Dallas-Cass-Adair-
217 PM CDT Sat May 1 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING
FOR EXTREME FIRE CONDITIONS....

* AFFECTED AREA...Portions of western, central and northern Iowa.

* WIND...Southwest winds of 25 to 35 mph, gusting in excess of 45
  mph at times.

* HUMIDITY...15 to 20 percent this afternoon, then slowly 
  climbing later in the day.

* IMPACTS...Any fires that develop will likely spread rapidly. 
  Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly. A combination of
strong winds, low relative humidity, and warm temperatures can
contribute to extreme fire behavior.

&&

$$

Lee
777 
WWUS83 KDMX 020001
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
701 PM CDT Sat May 1 2021

IAZ004>007-015>017-023>028-033>039-044>048-057>059-070-071-020115-
/O.EXP.KDMX.FW.W.0005.000000T0000Z-210502T0000Z/
Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo-
Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun-
Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-
Boone-Story-Audubon-Guthrie-Dallas-Cass-Adair-
701 PM CDT Sat May 1 2021

...RED FLAG WARNING WILL EXPIRE AT 7 PM CDT THIS EVENING FOR
EXTREME FIRE CONDITIONS....

Winds should diminish somewhat this evening, especially with
respect to gusts, so the Red Flag Warning will be allowed to
expire at 7 PM.

Although extreme conditions are not expected later this evening,
fire weather conditions will still remain somewhat elevated into 
the night due to warm temperatures and low humidities, as well as 
dry grasses and crop debris. Outdoor burning is still not 
recommended as fires could develop and spread relatively quickly.

$$

Small

Nearby

Red Flag Warnings in Iowa, 2021Every red flag warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.