Expected

* WHAT...Dangerously hot conditions with temperatures 98 to 102 with little overnight relief through Sunday. * WHERE...Castle Country, San Rafael Swell, Western Millard and Juab Counties, Great Salt Lake Desert and Mountains, Northern Wasatch Front, Salt Lake Valley, and Tooele and Rush Valleys. * WHEN...Until midnight MDT Sunday Night. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. Drink plenty of fluids, stay in an air-conditioned room, stay out of

* WHAT...Dangerously hot conditions with temperatures up to 110. * WHERE...Glen Canyon Recreation Area/Lake Powell, Lower Washington County, and Zion National Park. * WHEN...Until 9 PM MDT this evening. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.

* WHAT...Dangerously hot conditions with temperatures up to 105. * WHERE...Capitol Reef National Park and Vicinity, South Central Utah, and Western Canyonlands. * WHEN...Until 9 PM MDT this evening. * IMPACTS...Heat related illnesses increase significantly during extreme heat events. Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.

...GUSTY WINDS AND VERY LOW HUMIDITY THIS WEEKEND... * AFFECTED AREA...Fire Weather Zone 475 East Salmon River Mountains/Salmon NF and Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF. * WINDS...West 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 12 percent. * IMPACTS...Wind and low humidity can lead to rapid spread of fire. A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly based on these criteria for Southeastern Idaho:

* AFFECTED AREA...Lincoln Ranger District of the Helena National Forest, Central and Eastern Lewis and Clark National Forest Areas and Helena and Townsend Ranger Districts of the Helena National Forest. * WINDS...Northwest 5 to 15 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 12 percent. * TEMPERATURES...Up to 92. * IMPACTS...Any fires that develop will spread rapidly. Containment of any ongoing or new fires may be very difficult. Outdoor burning is not recommended.

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING DUE TO GUSTY WINDS AND LOW RELATIVE HUMIDITY FOR NORTHERN FOOT HILLS, BUTTE COUNTY AREA, NORTHERN CAMPBELL, SOUTHERN CAMPBELL, CROOK COUNTY PLAINS, WESTON COUNTY PLAINS, AND WYOMING BLACK HILLS... * AFFECTED AREA...Fire Weather Zones 314, 315, 316, 317, 318, 323, and 327. * TIMING...Until 8 PM MDT this evening. * WINDS...Northwest winds 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...Relative Humidity between 8 to 15 percent.

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM PDT THIS EVENING FOR DRY THUNDERSTORMS AND GUSTY OUTFLOW WINDS FOR FIRE WEATHER ZONES 425 AND 426... * AFFECTED AREA...Fire weather zones 425 and 426. * WIND...West winds up to 5-10 mph, gust 10-15 mph. Gusty erraticoutflow winds from passing/collapsing thunderstorms can reach up to 40-50 mph. * HUMIDITY...15-20 percent * THUNDERSTORMS...Thunderstorms will be mostly dry. * HIGHEST THREAT...is located in fire zone NV425. * IMPACTS...any fires that develop will likely spread rapidly.

* AFFECTED AREA: In Central WY Fire Zones...280...283...285...288...289...300. In North Central WY Fire Zones...275...276...281...282...287. In Northwest WY Fire Zones...140...286. In Southwest WY Fire Zones...277...279. In West Central WY Fire Zone....278. * COUNTIES AFFECTED: In Central WY...Fremont...Natrona. In North Central WY...Big Horn...Hot Springs...Johnson...Park Washakie. In Northwest WY...Yellowstone National Park.

...GUSTY WINDS AND VERY LOW HUMIDITY THIS WEEKEND... * AFFECTED AREA...Fire Weather Zone 475 East Salmon River Mountains/Salmon NF and Fire Weather Zone 476 Lemhi and Lost River Range/Challis NF. * WINDS...West 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 12 percent. * IMPACTS... 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

* WHAT...The Heat Advisory has been replaced with an Extreme Heat Warning. High temperatures up to 108 degrees and multiple days of Major Heat Risk. * WHERE...West Side Mountains north of 198. * WHEN...Until 8 PM PDT Monday. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. * ADDITIONAL DETAILS...The Heat Advisory has been replaced with an Extreme Heat Warning. Afternoon high temperatures of 105 to 109 degrees will occur daily through Monday. Overnight lows will