WWA Summary for All Issued by SLC

Red Flag Warning

URGENT - FIRE WEATHER MESSAGE
National Weather Service Pocatello ID
317 AM MDT Sat Aug 22 2026

...CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED ON SATURDAY DUE
TO SCATTERED THUNDERSTORM ACTIVITY ACROSS MUCH OF EASTERN IDAHO...

IDZ410-422-425-427-475-476-230300-
/O.CON.KPIH.FW.W.0022.260822T1800Z-260823T0300Z/
Upper Snake River Valley/Idaho Falls BLM-
Sawtooth Range/Northern Sawtooth NF-
Middle Snake River Valley/Twin Falls BLM north of the Snake River-
Goose Creek and Raft River Valley/Southern Sawtooth NF/Twin Falls
BLM south of the Snake River-
East Salmon River Mountains/Salmon NF-
Lemhi and Lost River Range/Challis NF-
317 AM MDT Sat Aug 22 2026

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 9 PM MDT
THIS EVENING FOR SCATTERED THUNDERSTORMS FOR FIRE WEATHER ZONES
410, 422, 425, 427, 475, AND 476...

* AFFECTED AREA...Fire Weather Zone 410 Upper Snake River
  Valley/Idaho Falls BLM, Fire Weather Zone 422 Sawtooth
  Range/Northern Sawtooth NF, Fire Weather Zone 425 Middle Snake
  River Valley/Twin Falls BLM north of the Snake River, Fire
  Weather Zone 427 Goose Creek and Raft River Valley/Southern
  Sawtooth NF/Twin Falls BLM south of the Snake River, Fire
  Weather Zone 475 East Salmon River Mountains/Salmon NF and
  Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF.

* IMPACTS...Frequent lightning will increase risk of new fire
  starts.

* THUNDERSTORMS...Scattered coverage with frequent lightning.

* OUTFLOW WINDS...Gusty and erratic winds to 60 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will shortly based on these criteria
for Southeastern Idaho:

- Relative humidity at or below 15 percent and wind gusts of at
least 25 mph in the mountains, or 30 mph in the Snake Plain.

- Thunderstorm coverage of 25 percent, without specific rainfall
criteria.

- Other high impact events deemed critical by the National
Weather Service and area fire management agencies.

&&

$$

URGENT - FIRE WEATHER MESSAGE
National Weather Service Boise ID
520 PM MDT Fri Aug 21 2026

...GUSTY WINDS AND LOW RELATIVE HUMIDITIES ACROSS PORTIONS OF
SOUTHEAST OREGON DISTRICTS...
...SCATTERED THUNDERSTORMS WITH LIGHTNING EXPECTED ACROSS
PORTIONS OF SOUTHWEST IDAHO DISTRICTS...

Pre-frontal winds pick up on Saturday with afternoon wind gusts
up to 35 mph at the same time RHs are 10-15% across Oregon zones
670, 671 and 672. In addition, isolated thunderstorms are
possible over mountains early Saturday increasing in coverage
across portions of Southwest Idaho Saturday afternoon and
evening. Isolated thunderstorms possible across the Vale district
Saturday afternoon with frontal passage. Storms that do develop
will be fairly strong, capable of producing lightning, outflow
gusts up to 50 mph, and heavy rain.

IDZ401>403-421-424-426-222100-
/O.NEW.KBOI.FW.W.0019.260822T1800Z-260823T0600Z/
Western Payette National Forest-Eastern Payette National Forest-
Northern Boise National Forest-
Southern Boise/Western Sawtooth NF, including the Camas Prairie-
Western Twin Falls BLM-Southern Highlands-
520 PM MDT Fri Aug 21 2026

...RED FLAG WARNING IN EFFECT FROM NOON SATURDAY TO MIDNIGHT MDT
SATURDAY NIGHT FOR LIGHTNING FOR WESTERN PAYETTE NATIONAL
FOREST...EASTERN PAYETTE NATIONAL FOREST... NORTHERN BOISE
NATIONAL FOREST...SOUTHERN BOISE/WESTERN SAWTOOTH NF, INCLUDING
THE CAMAS PRAIRIE...WESTERN TWIN FALLS BLM AND SOUTHERN
HIGHLANDS...WHICH ARE FIRE WEATHER ZONES 401...402...
403...421...424 AND 426...

The National Weather Service in Boise has issued a Red Flag
Warning for lightning, which is in effect from noon Saturday to
midnight MDT Saturday night.

* AFFECTED AREA...In Idaho, Fire Weather Zones 401 Western
  Payette National Forest, 402 Eastern Payette National Forest,
  403 Northern Boise National Forest, 421 Southern Boise/Western
  Sawtooth NF, including the Camas Prairie, 424 Western Twin
  Falls BLM and 426 Southern Highlands.

* TIMING...From noon Saturday to midnight MDT Saturday night.

* THUNDERSTORMS...Scattered coverage with abundant lightning.

* OUTFLOW WINDS...Gusty erratic winds up to 50 mph.

* IMPACTS...Any fire that develops will catch and spread
  quickly. Outdoor burning is not recommended.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions
are either occurring now, or will occur shortly.

&&

$$
W

Heat Advisory

URGENT - WEATHER MESSAGE
National Weather Service Salt Lake City UT
1234 PM MDT Fri Aug 21 2026

UTZ101>106-221300-
/O.CON.KSLC.HT.Y.0008.000000T0000Z-260822T1300Z/
Great Salt Lake Desert and Mountains-Tooele and Rush Valleys-
Eastern Box Elder County-Northern Wasatch Front-Salt Lake Valley-
Utah Valley-
Including the following locations - Dugway, Park Valley, Salt
Lake City, Payson, Snowville, Tooele, Ogden, Bountiful, West Jordan,
Provo, Brigham City, Vernon, Wendover, Lehi, Grantsville, and Sandy
1234 PM MDT Fri Aug 21 2026

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 AM MDT SATURDAY...

* WHAT...High temperatures to around 100 degrees expected alongside
  overnight low temperatures in the low- to mid-70s.

* WHERE...The Wasatch Front, Great Salt Lake Desert and Mountains,
  and Tooele and Rush Valleys.

* WHEN...Until 7 AM MDT Saturday.

* IMPACTS...Hot temperatures may cause heat illness. Warm overnight
  temperatures will limit the amount of relief from the hot daytime
  temperatures, bringing a period of prolonged heat exposure,
  especially for vulnerable populations.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of
the sun, and check up on relatives and neighbors.

Take extra precautions when outside. Wear lightweight and loose
fitting clothing. Try to limit strenuous activities to early morning
or evening. Take action when you see symptoms of heat exhaustion and
heat stroke.

To reduce risk during outdoor work, the Occupational Safety and
Health Administration recommends scheduling frequent rest breaks in
shaded or air conditioned environments. Anyone overcome by heat
should be moved to a cool and shaded location. Heat stroke is an
emergency! Call 9 1 1.

&&

$$

For more information from the National Weather Service visit
https://weather.gov/saltlakecity.

For information on potential travel impacts visit
http://udottraffic.utah.gov

Webber