Red Flag Warning 13, NWS Riverton, WY

340 
WWUS85 KRIW 280659
RFWRIW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Riverton WY
1259 AM MDT Wed Aug 28 2024

WYZ276>280-283-285-287-289-300-414-290200-
/O.CON.KRIW.FW.W.0013.240828T1600Z-240829T0200Z/
Cody Foothills-Lincoln and Uinta Counties/Lower Elevations-
Upper Green River Basin/Rock Springs BLM-
Sweetwater County/Rock Springs BLM/Flaming Gorge NRA-
Natrona County/Casper BLM-Upper Wind River Basin/Wind River Basin-
South Bighorn Mountains-Owl Creek Mountains-
Granite/Green/Ferris/Rattlesnake Mountains-Casper Mountain-
Salt and Wyoming Ranges/West Zone Bridger Teton NF-
1259 AM MDT Wed Aug 28 2024

...RED FLAG WARNING REMAINS IN EFFECT FROM 10 AM THIS MORNING TO
9 PM MDT THIS EVENING...

* AFFECTED AREA: 
  In Central WY Fire Zones...280...283...285...289...300.
  In North Central WY Fire Zones...276...287.
  In Southwest WY Fire Zones...277...279.
  In West Central WY Fire Zones...278...414.

* COUNTIES AFFECTED: 
  In Central WY...Fremont...Natrona.
  In North Central WY...Hot Springs...Johnson...Park...Washakie.
  In Southwest WY...Sweetwater...Uinta.
  In West Central WY...Lincoln...Sublette.

* IMPACTS: Low Humidities...Strong Gusty Winds...and Wind Shift 
  with a Cold Front could cause erratic fire behavior. 

* COLD FRONT: Winds will shift to the north northwest during the
  afternoon hours and remain through the evening. 

* WIND: Initially, Southwest to West 15 to 25 mph with gusts up to
  40 mph before turning to the north to northwest with initial 
  gusts up to 45 mph possible before subsiding during the evening. 

* HUMIDITY: As low as 10 to 15 percent.

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

226 
WWUS85 KRIW 290154
RFWRIW

URGENT - FIRE WEATHER MESSAGE
National Weather Service Riverton WY
754 PM MDT Wed Aug 28 2024

WYZ276>280-283-285-287-289-300-414-290300-
/O.EXP.KRIW.FW.W.0013.000000T0000Z-240829T0200Z/
Cody Foothills-Lincoln and Uinta Counties/Lower Elevations-
Upper Green River Basin/Rock Springs BLM-
Sweetwater County/Rock Springs BLM/Flaming Gorge NRA-
Natrona County/Casper BLM-Upper Wind River Basin/Wind River Basin-
South Bighorn Mountains-Owl Creek Mountains-
Granite/Green/Ferris/Rattlesnake Mountains-Casper Mountain-
Salt and Wyoming Ranges/West Zone Bridger Teton NF-
754 PM MDT Wed Aug 28 2024

...RED FLAG WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING...

Humidity values are increasing as temperatures drop this evening.
Wind is also decreasing as the sun sets, which has led to improved
fire weather conditions. Thus, the Red Flag Warning will be allowed
to expire. Elevated fire weather conditions will continue for a few
hours before wind fully dies down and RH improves moderately tonight.

$$

http://weather.gov/riverton

Area Forecast Discussion
National Weather Service Riverton WY
1002 AM MDT Tue Aug 27 2024

.KEY MESSAGES...

- Mild and breezy Tuesday with elevated fire weather conditions.

- Critical fire weather conditions Wednesday as a storm system
  passes to the north. Isolated storms possible along the
  northern counties to the Montana state line.

- Elevated fire weather conditions Thursday with dry conditions
  expected through the weekend.

&&

.DISCUSSION...
Issued at 1226 AM MDT Tue Aug 27 2024

IR currently depicts clear skies across much of the state as
induce upper level ridging has briefly built in from the south.
Breezy southwest winds and mild temperatures this afternoon as
another storm system pushes near from the northwest for
Wednesday. The bulk of this energy will be well to the north
near the Canada/Montana line but extend into northern portions
of the CWA that will some isolated storms late Wednesday
afternoon and evening. Severe weather is not expected, but winds
will increase with a tightening pressure gradient around 5-6 mb
across the CWA. Southwest winds for much of the afternoon with
gusts over 30-35 mph that will turn more northerly as a weak
cold front pushes through later in the evening. Timing wise,
this should not bump afternoon high temperatures down being a
later FROPA. This will, however, bring the milder temperatures
once again Thursday with lingering breezy winds throughout the
afternoon.

Once this aforementioned upper level low pushes east, ridging
builds back in from the south with weak winds aloft. Dry
conditions and a warming trend back to average and above average
into the weekend with highs back to near 90 degrees east of the
Divide. Otherwise, the next best chance for any precipitation
will be early next week dependent on another system pushing out
of the Pacific northwest and what kind of impact it will have
with its track eastward. The main focus, unfortunately will be
fire weather and hazy conditions from ongoing fires.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1000 AM MDT Tue Aug 27 2024

Clear skies and light winds prevail today and tonight, with
minimal aviation weather concerns.

During the late morning to early afternoon on Wednesday, breezy
winds will develop for most lower elevations. Wind gusts of 25
to 30 kt will be common through the afternoon hours as a dry
weather system passes through the region.

&&

.FIRE WEATHER...
Issued at 1226 AM MDT Tue Aug 27 2024

Elevated fire weather conditions expected for Tuesday afternoon
as a southwest wind develops by late morning. Gusts up to 20-25
mph likely for areas along and east of the wind corridor from
Sweetwater County through Muddy Gap and along the I-25 corridor
in lee of the Bighorns. Relative humidity values in these areas
will be in the 15-20 percent range during peak heating of the
afternoon with dry conditions expected.

Wednesday will see a tightening gradient ahead of a weak cold
front. Southwest wind gusts expected to be up to 30-35 mph in
these same areas, and a bit less for other areas east of the
Divide. Near critical to critical conditions expected as
relative humidity values will be a bit lower in the 10 to 15
percent range in this wind corridor area and up to 20 percent
to the Divide. The key to Wednesday will be FROPA that will push
through northwest to southeast late afternoon and into the
evening hours. Winds will switch more northerly but weaken into
the waning hours of daylight and overnight into Thursday. Wind
gusts up to 20-25 mph still expected Thursday but not as low
relative humidity values due to cooler temperatures. Elevated
fire concerns continue through the weekend with dry conditions
expected.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
Fire Weather Watch from Wednesday afternoon through Wednesday
evening for WYZ275-276-279>283-285-287-289-300.

&&

DISCUSSION...Lowe
AVIATION...VandenBoogart
FIRE WEATHER...Lowe

Hazardous Weather Outlook
National Weather Service Riverton WY
1255 AM MDT Tue Aug 27 2024

WYZ001>020-022>030-281100-
Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Bighorn Basin-Southwest Bighorn Basin-Southeast Bighorn Basin-
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-Northeast Johnson County-
Southeast Johnson County-Teton and Gros Ventre Mountains-
Jackson Hole-Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
1255 AM MDT Tue Aug 27 2024

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...Today and Tonight.

Elevated fire weather conditions expected during the afternoon and
early evening Tuesday with breezy southwest winds and low relative
humidity values.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Near critical to critical fire weather conditions for areas east of
the Divide Wednesday due to gusty southwest winds that will turn
northerly behind a cold front late in the afternoon and evening.
Isolated thunderstorm chances for northern counties along the cold
front in the late afternoon and early evening hours.

Dry conditions and elevated fire weather conditions for the remainder
of the period.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.