An extreme heat warning remains in effect through Friday for the Mojave Desert as temperatures are forecast to soar well above normal, according to the National Weather Service. This dangerous heat arrives as shifting atmospheric patterns prepare to bring a resurgence of monsoon moisture and potential thunderstorms to parts of Utah.
Extreme Heat and High Pressure
The National Weather Service Las Vegas issued an area forecast discussion on Wednesday, August 26, 2026, noting that high pressure centered over Arizona and New Mexico is gradually shifting west. This movement is expected to result in increasing heights, leading to temperatures that are well above normal. Wednesday and Thursday are anticipated to be the hottest days of the week, with most areas seeing readings approximately 8 to 10 degrees above normal.
While afternoon high temperatures have reached these levels earlier in the summer without heat headlines, officials warned that there is historically a resurgence of heat-related impacts at the end of the season. An approaching trough over the eastern Pacific is expected to help suppress the high pressure on Friday by lowering heights and bringing slightly cooler temperatures, though they will remain several degrees above normal.
Saint George Heat Forecast
In Saint George, the heat is expected to be intense. The National Weather Service forecast for Saint George on Wednesday, August 26, 2026, predicts a high near 108 degrees with a low around 80 degrees. High temperatures are expected to remain at 108 degrees through Thursday before dropping to 105 degrees on Friday.
As the week progresses, the weather pattern is expected to shift. A 10 percent chance of showers and thunderstorms is forecast for Friday afternoon, with a slight chance of storms Friday night. By Saturday, the chance of precipitation increases to 30 percent with a high of 100 degrees, followed by continued chances for showers and thunderstorms through Sunday and Monday.
Salt Lake City Climate Data
The National Weather Service Salt Lake City provided a detailed monthly climate summary for August 2026, noting that temperatures in Salt Lake City have remained consistently high. On August 1, the city recorded a high of 105 degrees and a low of 73 degrees. Throughout the month, the city has experienced significant heat, with 20 days recording temperatures of 90 degrees or higher.
Climatological data shows that Salt Lake City has seen a total of 435 cumulative degree-days above 65 degrees for the month of August. The city also recorded a maximum wind gust of 44 mph on August 17. While precipitation has been relatively low, with a total of 1.30 inches for the month through August 24, the region has experienced several instances of measurable rainfall.
Heat Illness Prevention
The Utah Department of Health and Human Services, through its Violence and Injury Prevention Program, issued guidance on August 6, 2026, regarding heat illness. The agency noted that high heat temperatures harm both physical and mental health, and these risks are exacerbated by poor air quality. The impact of heat depends on individual factors such as age, health, location, and access to air conditioning.
To mitigate risks, the agency recommends drinking water throughout the day without waiting for thirst, which is a sign of dehydration. Other safety measures include taking regular breaks in cool, shaded, or air-conditioned areas, wearing lightweight and loose-colored clothing, and avoiding strenuous physical activity during the hottest part of the day, typically between 2 p.m. and 6 p.m.
Previous Weather Advisories
The National Weather Service warned earlier in the month of potential weather hazards. On August 11, 2026, the agency issued a heat advisory for the Wasatch Front, Great Salt Lake Desert, and Tooele and Rush Valleys, effective from noon Thursday through 7 a.m. Saturday. The advisory noted that high temperatures around 100 degrees combined with warm overnight lows could limit relief from the heat, creating a period of prolonged exposure for vulnerable populations.
Additionally, the agency had previously issued a marginal risk of excessive rainfall for much of Utah through mid-August. This included an increased threat of flash flooding, particularly in slot canyons, normally dry washes, slick rock areas, and recent burn scars. Such flooding can be life-threatening in creeks, streams, urban areas, and underpasses.
Upcoming Weather Transitions
As the heat persists, weather models suggest a transition in the coming days. The National Weather Service indicated that an approaching trough is expected to bring a resurgence of mid-level moisture to the region along with continued weak instability. This may result in more widespread convection and scattered showers and thunderstorms, particularly by Thursday.
By Friday and into the weekend, the trough is expected to bring much drier air into the region, which should result in the end of thunderstorm chances across the forecast area. Residents are encouraged to continue monitoring local forecasts as the weather patterns evolve.
