Alert archive / Iowa / Red Flag Warnings in 2021

Red Flag Warning 3, NWS Des Moines, IA

March 28, 202142 counties in Iowa

NWS Des Moines, IA issued this red flag warning at Mar 28, 2021, 2:52 PM CDT for 42 counties in Iowa. It took effect at Mar 29, 2021, 12:00 PM CDT. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Mar 28, 2021, 2:52 PM CDT (19:52 UTC)
In effect from
Mar 29, 2021, 12:00 PM CDT
Expired
Mar 29, 2021, 8:00 PM CDT
In force
8 hr
Issued by
NWS Des Moines, IA
All 42 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Black Hawk County, IA, Boone County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Clarke County, IA, Crawford County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Humboldt County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Palo Alto County, IA, Pocahontas County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Sac County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 6 km from the middle of the area, began a volume at 19:53 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 12:00Z, 7.9 hours before the alert went out and 220 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 12:00Z on 2021-03-28Temperature 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 12:00Z on 2021-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.1939587897Sfc1 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
1259 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
223 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

319 
WWUS83 KDMX 281952
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
252 PM CDT Sun Mar 28 2021

...Extreme Fire Weather Conditions Monday Afternoon Across Much 
of Iowa...

.The combination of warming temperatures, strong southerly winds
and wind gusts, lowering humidities, and relatively dry prairie 
grasses and other fuels will create extreme fire weather 
conditions by Monday afternoon across large portions of Iowa.

IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
290400-
/O.UPG.KDMX.FW.A.0001.210329T1700Z-210330T0100Z/
/O.NEW.KDMX.FW.W.0003.210329T1700Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
252 PM CDT Sun Mar 28 2021

...RED FLAG WARNING IN EFFECT FROM NOON TO 8 PM CDT MONDAY 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 noon
to 8 PM CDT Monday. The Fire Weather Watch is no longer in 
effect.

* IMPACTS...Any fires that start Monday afternoon may spread 
  rapidly and become uncontrollable. 

* RELATIVE HUMIDITY...As low as 25 percent during the afternoon.

* WIND...Strong south to southwest winds with sustained speeds to
  around 25 mph, and gusts to 45 mph possible. Wind gusts in
  excess of 50 mph may be possible for a brief period mid to late
  afternoon.  

* FUEL...Prairie grasses and any lingering crop debris will dry
  out quickly in these conditions and may be able to burn easily.

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.

&&

$$

CURTIS
5 follow-up statements
010 
WWUS83 KDMX 290159
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
859 PM CDT Sun Mar 28 2021

...Extreme Fire Weather Conditions Monday Afternoon Across Much
of Iowa...

.The combination of warming temperatures, strong southerly wind, 
low relative humidity, and relatively dry prairie grasses and 
other fuels will create extreme fire weather conditions by Monday 
afternoon across large portions of Iowa.

IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
291000-
/O.CON.KDMX.FW.W.0003.210329T1700Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
859 PM CDT Sun Mar 28 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TO 8 PM CDT
MONDAY FOR EXTREME FIRE CONDITIONS...

* IMPACTS...Any fires that start Monday afternoon may spread 
  rapidly and become uncontrollable.

* Relative Humidity...Minimum relative humidity between 20 and 30
  percent during the afternoon.

* WIND...Strong south to southwest winds with sustained speeds of
  25 to 35 mph, with gusts over 50 mph possible.

* FUEL...Prairie grasses and any lingering crop debris will dry
  out quickly in these conditions and may be able to burn easily
  and lead to extremely fast fire growth.

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.

&&

$$
827 
WWUS83 KDMX 290859
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
359 AM CDT Mon Mar 29 2021

...Extreme Fire Weather Conditions This Afternoon Across Much of 
Iowa...

.The combination of warm temperatures, strong southerly wind, low
relative humidity, and relatively dry prairie grasses and other 
fuels will create extreme fire weather conditions by this
afternoon across large portions of Iowa.

IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
291700-
/O.CON.KDMX.FW.W.0003.210329T1700Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
359 AM CDT Mon Mar 29 2021

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 8 PM CDT
THIS EVENING FOR EXTREME FIRE CONDITIONS...

* IMPACTS...Any fires that start this afternoon may spread 
  rapidly and become uncontrollable.

* RELATIVE HUMIDITY...As low as 28 percent.

* WIND...Strong south to southwest winds with sustained speeds 
  of 25 to 35 mph, with gusts over 50 mph possible.

* FUEL...Prairie grasses and any lingering crop debris will dry 
  out quickly in these conditions and may be able to burn easily 
  and lead to extremely fast fire growth.

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.

&&

$$

Small
007 
WWUS83 KDMX 291505
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
1005 AM CDT Mon Mar 29 2021

...Extreme Fire Weather Conditions Through this Afternoon...

.The combination of warm temperatures, strong southerly wind, low
relative humidity, and relatively dry prairie grasses and other
vegetation will lead to extreme fire weather conditions over much
of Iowa today.

IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
292315-
/O.CON.KDMX.FW.W.0003.210329T1700Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
1005 AM CDT Mon Mar 29 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING
FOR EXTREME FIRE CONDITIONS...

* IMPACTS...Any fires that start today may spread rapidly and 
  become uncontrollable. 

* RELATIVE HUMIDITY...As low as 28 percent.

* WIND...Strong south to southwest winds with sustained speeds 
  of 25 to 35 mph, with gusts over 50 mph possible.

* FUEL...Prairie grasses and any lingering crop debris will dry 
  out quickly in these conditions and may be able to burn 
  easily and lead to extremely fast fire growth.

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.

&&

$$

KLP
765 
WWUS83 KDMX 292029
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
329 PM CDT Mon Mar 29 2021

...Extreme Fire Weather Conditions Through this Evening...

.The combination of warm temperatures, strong southerly wind, low
relative humidity, and relatively dry prairie grasses and other
vegetation will lead to extreme fire weather conditions over much
of Iowa into the evening hours.

IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
300100-
/O.CON.KDMX.FW.W.0003.000000T0000Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
329 PM CDT Mon Mar 29 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING
FOR EXTREME FIRE CONDITIONS...

* IMPACTS...Any fires that start today may spread rapidly and 
  become uncontrollable. 

* RELATIVE HUMIDITY...As low as 25 percent.

* WIND...Strong south to southwest winds with sustained speeds 
  of 25 to 35 mph, with gusts over 50 mph possible.

* FUEL...Prairie grasses and any lingering crop debris will dry 
  out quickly in these conditions and may be able to burn 
  easily and lead to extremely fast fire growth.

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.

&&

$$

KLP
878 
WWUS83 KDMX 300055
RFWDMX

URGENT - FIRE WEATHER MESSAGE
National Weather Service Des Moines IA
755 PM CDT Mon Mar 29 2021


IAZ015-023>025-033>039-044>050-057>062-070>075-081>086-092>097-
300200-
/O.EXP.KDMX.FW.W.0003.000000T0000Z-210330T0100Z/
Palo Alto-Pocahontas-Humboldt-Wright-Sac-Calhoun-Webster-Hamilton-
Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene-Boone-Story-
Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-
Adair-Madison-Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-
Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
755 PM CDT Mon Mar 29 2021

...RED FLAG WARNING WILL EXPIRE AT 8 PM CDT THIS EVENING FOR
EXTREME FIRE CONDITIONS....

The Red Flag Warning will expire at 8 pm.

$$

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 28, 4:22 AM CDTFire Weather WatchDMXAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 36 more11 hr
Mar 28, 3:02 PM CDTWind AdvisoryDMXAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more29 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.