Alert archive / Wyoming / Red Flag Warnings in 2021

Red Flag Warning 21, NWS Rapid City, SD

August 25, 2021Campbell County, Wyoming

NWS Rapid City, SD issued this red flag warning at Aug 25, 2021, 3:50 AM MDT for Campbell County, Wyoming. It took effect at Aug 25, 2021, 12:00 PM MDT. 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
Aug 25, 2021, 3:50 AM MDT (09:50 UTC)
In effect from
Aug 25, 2021, 12:00 PM MDT
Expired
Aug 25, 2021, 6:09 PM MDT
In force
6 hr
Issued by
NWS Rapid City, SD

County Campbell County, WY

The nearest sounding before it

Rapid City, SD (KUNR), launched 00:00Z, 9.8 hours before the alert went out and 214 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, Rapid City, SD at 00:00Z on 2021-08-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Rapid City, SD at 00:00Z on 2021-08-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.19395878Sfc1 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
2566 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
307 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

902 
WWUS83 KUNR 250950
RFWUNR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Rapid City SD
350 AM MDT Wed Aug 25 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS
EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR CAMPBELL
COUNTY...

.Warm, dry, and breezy conditions can be expected across much of
Campbell County this afternoon, especially western portions of the
county. Relative humidities will drop into the teens, with
southerly winds of 10 to 20 mph and gusts to around 30 mph. Red
flag conditions are most likely to develop across areas west of 
Gillette and Wright. Conditions will gradually improve early this 
evening.


WYZ314-315-260100-
/O.UPG.KUNR.FW.A.0016.210825T1700Z-210826T0200Z/
/O.NEW.KUNR.FW.W.0021.210825T1800Z-210826T0200Z/
Northern Campbell-Southern Campbell-
350 AM MDT Wed Aug 25 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS
EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE
WEATHER ZONES 314 AND 315...

The National Weather Service in Rapid City has issued a Red Flag
Warning for gusty winds and low relative humidity, which is in
effect from noon today to 8 PM MDT this evening. The Fire Weather
Watch is no longer in effect.

* AFFECTED AREA...Fire Weather Zones 314 Northern Campbell and 
  315 Southern Campbell.

* WINDS...South 10 to 20 mph with gusts up to 30 mph.

* RELATIVE HUMIDITY...As low as 12 percent.

* IMPACTS...The combination of gusty winds and low relative 
  humidity would produce critical fire weather conditions.

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
023 
WWUS83 KUNR 252005
RFWUNR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Rapid City SD
205 PM MDT Wed Aug 25 2021

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 8 PM MDT THIS
EVENING FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR CAMPBELL
COUNTY...

.Warm, dry, and breezy conditions can be expected across much of
Campbell County this afternoon, especially western portions of
the county. Relative humidities will continue to drop into the 
teens, with southerly winds gusting up to 35 mph. Red flag 
conditions are most likely across areas west of Gillette and 
Wright. Conditions will gradually improve early this evening.

WYZ314-315-260200-
/O.CON.KUNR.FW.W.0021.000000T0000Z-210826T0200Z/
Northern Campbell-Southern Campbell-
205 PM MDT Wed Aug 25 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING
FOR GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES
314 AND 315...

* AFFECTED AREA...Fire Weather Zones 314 Northern Campbell and 
  315 Southern Campbell.

* WINDS...South 15 to 25 mph with gusts up to 35 mph.

* RELATIVE HUMIDITY...As low as 12 percent.

* IMPACTS...The combination of gusty winds and low relative 
  humidity would produce critical fire weather conditions.

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.

&&

$$
962 
WWUS83 KUNR 260009
RFWUNR

URGENT - FIRE WEATHER MESSAGE
National Weather Service Rapid City SD
609 PM MDT Wed Aug 25 2021

WYZ314-315-260115-
/O.CAN.KUNR.FW.W.0021.000000T0000Z-210826T0200Z/
Northern Campbell-Southern Campbell-
609 PM MDT Wed Aug 25 2021

...RED FLAG WARNING IS CANCELLED FOR GUSTY WINDS AND LOW RELATIVE
HUMIDITY FOR FIRE WEATHER ZONES 314 AND 315...

The National Weather Service in Rapid City has cancelled the Red
Flag Warning.

The relative humidity has increased to above 25 percent for most
locations.

$$

Bunkers

Nearby

Red Flag Warnings in Wyoming, 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.