Alert archive / Wyoming / Red Flag Warnings in 2007

Red Flag Warning 13, NWS Riverton, WY

September 28, 2007Fremont County, Natrona County, Sweetwater County, Wyoming

NWS Riverton, WY issued this red flag warning at Sep 28, 2007, 1:35 PM MDT for Fremont County, Natrona County, Sweetwater County, Wyoming. It was in force for 4 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 28, 2007, 1:35 PM MDT (19:35 UTC)
Expired
Sep 28, 2007, 6:00 PM MDT
In force
4 hr
Issued by
NWS Riverton, WY

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

The radar

The Riverton/Lander radar (KRIW), 65 km from the middle of the area, began a volume at 19:38 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 12:00Z, 7.6 hours before the alert went out and 62 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 12:00Z on 2007-09-28Temperature 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 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2007-09-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 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
2941 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
24 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.

000 
WWUS85 KRIW 281935
RFWRIW

RED FLAG WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
135 PM MDT FRI SEP 28 2007

...WINDY...WARM AND DRY CONDITIONS COUPLED WITH THE DRY
VEGETATION WILL PRODUCE CRITICAL FIRE WEATHER CONDITIONS THIS AFTERNOON...

.WINDY...WARM AND DRY CONDITIONS COUPLED WITH THE DRY VEGETATION
WILL PRODUCE CRITICAL FIRE WEATHER CONDITIONS THIS AFTERNOON.

WYZ280-289-290000-
/O.NEW.KRIW.FW.W.0013.070928T1935Z-070929T0000Z/
NATRONA COUNTY / CASPER BLM-
GRANITE / GREEN / FERRIS / RATTLESNAKE MOUNTAINS-
135 PM MDT FRI SEP 28 2007

...RED FLAG WARNING IN EFFECT UNTIL 6 PM MDT THIS AFTERNOON...

THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT UNTIL 6 PM MDT THIS AFTERNOON. 

SOUTHWEST WINDS OF 20 TO 30 MPH WITH GUSTS TO 40 MPH AND RELATIVE
HUMIDITY IN THE LOWER TEENS WILL COMBINE WITH THE DRY VEGETATION TO
CREATE CRITICAL FIRE WEATHER CONDITIONS. THE RELATIVE HUMIDITY
WILL INCREASE AFTER 1800 WHICH WILL DECREASE THE CRITICAL
FIRE WEATHER CONDITIONS AFTER THAT TIME.

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.

$$

LIPSON
1 follow-up statement
000 
WWUS85 KRIW 282355
RFWRIW

RED FLAG WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
555 PM MDT FRI SEP 28 2007

WYZ280-289-290100-
/O.EXP.KRIW.FW.W.0013.000000T0000Z-070929T0000Z/
NATRONA COUNTY / CASPER BLM-
GRANITE / GREEN / FERRIS / RATTLESNAKE MOUNTAINS-
555 PM MDT FRI SEP 28 2007

...RED FLAG WARNING WILL EXPIRE AT 6 PM MDT THIS AFTERNOON...

THE RED FLAG WARNING WILL EXPIRE AT 6 PM MDT THIS AFTERNOON. 

RELATIVE HUMIDITY IS NOW GENERALLY BETWEEN 15 AND 20 PERCENT
ACROSS THE AREA...AND THE RELATIVE HUMIDITY IS EXPECTED TO
GRADUALLY INCREASE DURING THE EVENING HOURS. THEREFORE...THE RED
FLAG WARNING WILL BE ALLOWED TO EXPIRE. HOWEVER...STRONG
SOUTHWEST WINDS BETWEEN 15 AND 25 MPH...WITH GUSTS TO AROUND 30
MPH...ARE EXPECTED TO CONTINUE THROUGH EARLY EVENING.

$$

Nearby

Red Flag Warnings in Wyoming, 2007Every red flag warning in 2007

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.