Alert archive / Wyoming / Red Flag Warnings in 2014

Red Flag Warning 13, NWS Riverton, WY

September 25, 20144 counties in Wyoming

NWS Riverton, WY issued this red flag warning at Sep 25, 2014, 2:18 AM MDT for 4 counties in Wyoming. It took effect at Sep 25, 2014, 12:00 PM MDT. 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
Sep 25, 2014, 2:18 AM MDT (08:18 UTC)
In effect from
Sep 25, 2014, 12:00 PM MDT
Expired
Sep 25, 2014, 7:00 PM MDT
In force
7 hr
Issued by
NWS Riverton, WY

Counties Fremont County, WY, Johnson County, WY, Natrona County, WY, Sweetwater County, WY

The radar

The Riverton/Lander radar (KRIW), 63 km from the middle of the area, began a volume at 08:18 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

Riverton, WY (KRIW), launched 00:00Z, 8.3 hours before the alert went out and 57 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, Riverton, WY at 00:00Z on 2014-09-25Temperature 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 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 00:00Z on 2014-09-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 square meters per square second.1939Sfc1 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
3118 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
150 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.

748 
WWUS85 KRIW 250818
RFWRIW

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
218 AM MDT THU SEP 25 2014

...CRITICAL FIRE WEATHER EXPECTED ACROSS PORTIONS OF CENTRAL
WYOMING THIS AFTERNOON...

.A GUSTY SOUTHWESTERLY BREEZE WILL COMBINE WITH LOW RELATIVE
HUMIDITY...UNSEASONABLY WARM TEMPERATURES AND CRITICAL FUELS TO
BRING CRITICAL FIRE CONDITIONS THIS AFTERNOON.

WYZ280-281-289-252200-
/O.UPG.KRIW.FW.A.0004.140925T1800Z-140926T0100Z/
/O.NEW.KRIW.FW.W.0013.140925T1800Z-140926T0100Z/
NATRONA COUNTY/CASPER BLM-JOHNSON COUNTY/CASPER BLM-
GRANITE/GREEN/FERRIS/RATTLESNAKE MOUNTAINS-
218 AM MDT THU SEP 25 2014

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 7 PM MDT THIS
EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES
280...281 AND 289...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A RED FLAG
WARNING FOR WIND AND LOW RELATIVE HUMIDITY...WHICH IS IN EFFECT
FROM NOON TODAY TO 7 PM MDT THIS EVENING. THE FIRE WEATHER WATCH
IS NO LONGER IN EFFECT.

* AFFECTED AREA...FIRE WEATHER ZONES 280...281 AND 289.

* WINDS...SOUTHWEST 10 TO 20 MPH WITH GUSTS OF 25 TO 30 MPH.

* RELATIVE HUMIDITY...AS LOW AS 12 PERCENT.

* IMPACTS...CONDITIONS MAY BE FAVORABLE FOR INTENSE FIRES WITH 
  RAPID RATES OF SPREAD. 

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.

&&

$$

HTTP://WEATHER.GOV/RIVERTON
2 follow-up statements
380 
WWUS85 KRIW 251810
RFWRIW

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
1210 PM MDT THU SEP 25 2014

...CRITICAL FIRE WEATHER EXPECTED ACROSS PORTIONS OF CENTRAL
WYOMING THIS AFTERNOON...

.A GUSTY SOUTHWESTERLY BREEZE WILL COMBINE WITH LOW RELATIVE
HUMIDITY...UNSEASONABLY WARM TEMPERATURES AND CRITICAL FUELS TO
BRING CRITICAL FIRE CONDITIONS THIS AFTERNOON.

WYZ280-281-289-260100-
/O.CON.KRIW.FW.W.0013.000000T0000Z-140926T0100Z/
NATRONA COUNTY/CASPER BLM-JOHNSON COUNTY/CASPER BLM-
GRANITE/GREEN/FERRIS/RATTLESNAKE MOUNTAINS-
1210 PM MDT THU SEP 25 2014

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 7 PM MDT THIS EVENING
FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 280...
281 AND 289...

* AFFECTED AREA...FIRE WEATHER ZONES 280...281 AND 289.

* WINDS...SOUTHWEST 10 TO 20 MPH WITH GUSTS UP TO 30 MPH.

* RELATIVE HUMIDITY...AS LOW AS 13 PERCENT.

* IMPACTS...CONDITIONS MAY BE FAVORABLE FOR INTENSE FIRES WITH 
  RAPID RATES OF SPREAD. 

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.

&&

$$

HTTP://WEATHER.GOV/RIVERTON
153 
WWUS85 KRIW 260039
RFWRIW

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
639 PM MDT THU SEP 25 2014

WYZ280-281-289-260145-
/O.EXP.KRIW.FW.W.0013.000000T0000Z-140926T0100Z/
NATRONA COUNTY/CASPER BLM-JOHNSON COUNTY/CASPER BLM-
GRANITE/GREEN/FERRIS/RATTLESNAKE MOUNTAINS-
639 PM MDT THU SEP 25 2014

...RED FLAG WARNING WILL EXPIRE AT 7 PM MDT THIS EVENING FOR WIND
AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 280...281 AND
289...

WINDS HAVE WEAKENED EARLY THIS EVENING...AND ARE NO LONGER
EXPECTED TO MEET RED FLAG CONDITIONS. THUS THE RED FLAG WARNING
WILL BE ALLOWED TO EXPIRE AT 7 PM.

$$

21

Nearby

Red Flag Warnings in Wyoming, 2014Every red flag warning in 2014

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.