Alert archive / Iowa / Red Flag Warnings in 2012

Red Flag Warning 1, NWS Des Moines, IA

April 9, 20126 counties in Iowa

NWS Des Moines, IA issued this red flag warning at Apr 9, 2012, 3:49 AM CDT for 6 counties in Iowa. It took effect at Apr 9, 2012, 1:00 PM CDT. It was in force for 6 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
Apr 9, 2012, 3:49 AM CDT (08:49 UTC)
In effect from
Apr 9, 2012, 1:00 PM CDT
Expired
Apr 9, 2012, 7:00 PM CDT
In force
6 hr
Issued by
NWS Des Moines, IA

Counties Emmet County, IA, Humboldt County, IA, Kossuth County, IA, Palo Alto County, IA, Pocahontas County, IA, Sac County, IA

The radar

The Des Moines radar (KDMX), 151 km from the middle of the area, began a volume at 08:50 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, 8.8 hours before the alert went out and 228 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 2012-04-09Temperature 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, Minneapolis, MN at 00:00Z on 2012-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 square meters per square second.1939587897117Sfc1 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
3359 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

681 
WWUS83 KDMX 090849
RFWDMX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE DES MOINES IA
349 AM CDT MON APR 9 2012

...EXTREME FIRE CONDITIONS ARE EXPECTED THIS AFTERNOON IN NORTHWEST
PORTIONS OF CENTRAL IOWA...

.HIGH PRESSURE WILL SLIDE INTO IOWA TODAY BRINGING EVEN DRIER AIR
INTO NORTHWEST IOWA ALONG WITH AN INCREASING NORTHWEST WIND. WIND
SPEEDS AND RELATIVE HUMIDITY VALUES WILL DROP INTO RED FLAG WARNING
CRITERIA THIS AFTERNOON. WHILE GRASSES ARE GREENING UP THEY ARE
STILL NOT FULLY GREENED ADDING TO THE THREAT OF EXTREME FIRE CONDITIONS.

IAZ004-005-015-023-024-033-091700-
/O.NEW.KDMX.FW.W.0001.120409T1800Z-120410T0000Z/
EMMET-KOSSUTH-PALO ALTO-POCAHONTAS-HUMBOLDT-SAC-
349 AM CDT MON APR 9 2012

...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.

* SHORT TERM TRENDS...VERY DRY AIR WILL BE MOVING INTO NORTHWEST
  IOWA TODAY AND THIS COMBINED WITH INCREASING WIND SPEEDS WILL
  BRING EXTREME FIRE CONDITIONS TO THE WARNING AREA.

* WIND...A NORTHWEST WIND WILL INCREASE THROUGH THE MORNING AND
  BECOME SUSTAINED AT 25 MPH DURING THE AFTERNOON WITH GUSTS AS
  HIGH AS 35 MPH.

* RELATIVE HUMIDITY...AS LOW AS 18 PERCENT.

* FUEL...GRASSLANDS ARE NOT YET COMPLETELY MATURE MAY BE DRY IN AREAS.

* IMPACTS...ANY FIRES THAT START WILL SPREAD RAPIDLY DUE TO LOW
  RELATIVE HUMIDITY...A NORTHWEST WIND ABOVE 25 MPH AND LESS THAN
  MATURE FUELS.

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 WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$

FAB
2 follow-up statements
623 
WWUS83 KDMX 092108
RFWDMX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE DES MOINES IA
408 PM CDT MON APR 9 2012

...EXTREME FIRE CONDITIONS WILL CONTINUE LATE THIS AFTERNOON IN
NORTHWEST PORTIONS OF CENTRAL IOWA...

.STRONG NORTHWEST WINDS AND LOW RELATIVE HUMIDITY VALUES WILL LEAD
TO EXTREME FIRE DANGER FOR THE REST OF THIS AFTERNOON...

IAZ004-005-015-023-024-033-100000-
/O.CON.KDMX.FW.W.0001.000000T0000Z-120410T0000Z/
EMMET-KOSSUTH-PALO ALTO-POCAHONTAS-HUMBOLDT-SAC-
408 PM CDT MON APR 9 2012

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

* SHORT TERM TRENDS...WINDS WILL PERSIST LATE THIS AFTERNOON INTO
  THE EARLY EVENING BEFORE MIXING DECREASES WITH THE APPROACH OF
  SUNSET. THE DEEPER MIXING WILL ALSO PRODUCE LOW RELATIVE
  HUMIDITY VALUES FOR THE REMAINDER OF THE AFTERNOON.  

* WIND...SUSTAINED NORTHWEST WINDS AT 20 TO 25 MPH FOR THE LATE AFTERNOON
  WITH GUSTS AS HIGH AS 35 MPH.

* RELATIVE HUMIDITY...VARYING FROM 18 TO 25 PERCENT.

* FUEL...GRASSLANDS ARE NOT YET COMPLETELY MATURE MAY BE DRY IN 
  AREAS.

* IMPACTS...ANY FIRES THAT START WILL SPREAD RAPIDLY DUE TO LOW 
  RELATIVE HUMIDITY...A NORTHWEST WIND ABOVE 25 MPH AND LESS 
  THAN MATURE FUELS. 

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 WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$
772 
WWUS83 KDMX 092357
RFWDMX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE DES MOINES IA
657 PM CDT MON APR 9 2012

IAZ004-005-015-023-024-033-100100-
/O.EXP.KDMX.FW.W.0001.000000T0000Z-120410T0000Z/
EMMET-KOSSUTH-PALO ALTO-POCAHONTAS-HUMBOLDT-SAC-
657 PM CDT MON APR 9 2012

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

WITH SUNSET...WINDS ARE EXPECTED TO DIMINISH AS WELL AS DEW POINTS
RISING TO CREATE HIGHER RH VALUES. THEREFORE...THE RED FLAG
WARNING WILL BE ALLOWED TO EXPIRE AS THE HAZARDOUS BURNING
CONDITIONS HAVE IMPROVED.

$$

BEERENDS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 9, 3:51 AM CDTFreeze WarningDMXAdair, Adams, Appanoose, Audubon, Black Hawk, Boone and 45 more29 hr

Nearby

Red Flag Warnings in Iowa, 2012Every red flag warning in 2012

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.