Alert archive / South Dakota / Red Flag Warnings in 2021

Red Flag Warning 8, NWS Sioux Falls, SD

November 23, 202110 counties in South Dakota

NWS Sioux Falls, SD issued this red flag warning at Nov 23, 2021, 3:46 AM CST for 10 counties in South Dakota. It took effect at Nov 23, 2021, 11:00 AM CST. It was in force for 7 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
Nov 23, 2021, 3:46 AM CST (09:46 UTC)
In effect from
Nov 23, 2021, 11:00 AM CST
Expired
Nov 23, 2021, 6:00 PM CST
In force
7 hr
Issued by
NWS Sioux Falls, SD

Counties Aurora County, SD, Bon Homme County, SD, Brule County, SD, Charles Mix County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hanson County, SD, Hutchinson County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 127 km from the middle of the area, began a volume at 09:48 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

Aberdeen, SD (KABR), launched 00:00Z, 9.8 hours before the alert went out and 168 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, Aberdeen, SD at 00:00Z on 2021-11-23Temperature 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, Aberdeen, SD at 00:00Z on 2021-11-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 145 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
1707 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
145 m²/s²
0-3 km storm-relative helicity
194 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

265 
WWUS83 KFSD 230946
RFWFSD

URGENT - FIRE WEATHER MESSAGE
National Weather Service Sioux Falls SD
346 AM CST Tue Nov 23 2021

SDZ050-057>060-063>065-068-069-231800-
/O.UPG.KFSD.FW.A.0002.211123T1700Z-211124T0000Z/
/O.NEW.KFSD.FW.W.0008.211123T1700Z-211124T0000Z/
Gregory-Brule-Aurora-Davison-Hanson-Charles Mix-Douglas-
Hutchinson-Bon Homme-Yankton-
346 AM CST Tue Nov 23 2021

...RED FLAG WARNING IN EFFECT FROM 11 AM THIS MORNING TO 6 PM CST
THIS EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE 
WEATHER ZONES 050, 057, 058, 059, 060, 063, 064, 065, 068, AND 
069...

The National Weather Service in Sioux Falls has issued a Red Flag
Warning, which is in effect from 11 AM this morning to 6 PM CST
this evening. The Fire Weather Watch is no longer in effect. 

* AFFECTED AREA...Fire weather zones across portions of south
  central and southeast South Dakota.

* WIND...Southwest at 15 to 25 mph with gusts up to 30 mph.

* HUMIDITY...As low as 18 to 25 percent.

* 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.

&&

$$
2 follow-up statements
494 
WWUS83 KFSD 231637
RFWFSD

URGENT - FIRE WEATHER MESSAGE
National Weather Service Sioux Falls SD
1037 AM CST Tue Nov 23 2021

SDZ050-057>060-063>065-068-069-240000-
/O.CON.KFSD.FW.W.0008.211123T1700Z-211124T0000Z/
Gregory-Brule-Aurora-Davison-Hanson-Charles Mix-Douglas-
Hutchinson-Bon Homme-Yankton-
1037 AM CST Tue Nov 23 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 6 PM CST THIS EVENING
FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES
050, 057, 058, 059, 060, 063, 064, 065, 068, AND 069...

* AFFECTED AREA...Fire weather zones across portions of south 
  central and southeast South Dakota. 

* WIND...Southwest at 15 to 25 mph with gusts up to 30 mph.

* HUMIDITY...As low as 18 to 25 percent.

* 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.

&&

$$
689 
WWUS83 KFSD 240023
RFWFSD

URGENT - FIRE WEATHER MESSAGE
National Weather Service Sioux Falls SD
623 PM CST Tue Nov 23 2021

...RED FLAG WARNING FOR LOW HUMIDITY AND STRONG WINDS FOR PORTIONS
OF SOUTH CENTRAL AND SOUTHEAST SOUTH DAKOTA ALLOWED TO EXPIRE...


SDZ050-057>060-063>065-068-069-240130-
/O.EXP.KFSD.FW.W.0008.000000T0000Z-211124T0000Z/
Gregory-Brule-Aurora-Davison-Hanson-Charles Mix-Douglas-
Hutchinson-Bon Homme-Yankton-
623 PM CST Tue Nov 23 2021

...RED FLAG WARNING HAS EXPIRED FOR LOW HUMIDITY AND STRONG WINDS
FOR FIRE WEATHER ZONES 050, 057, 058, 059, 060, 063, 064, 065, 
068, AND 069...

Winds will continue to decrease early this evening, and relative 
humidity will also slowly recover as temperatures begin to fall.
However, for the next hour or two, there will still be some 
southerly winds gusting 25 to 30 mph and humidity of 20 to 25 
percent, creating continued very high to extreme fire danger.

$$

Nearby

Red Flag Warnings in South Dakota, 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.