Pioneer Day is only the first day in a long reprieve from the triple-digit heat.
Most of northern Utah can expect highs around the mid 90s through the end of the week, while southern Utahns continue to sizzle in peak temperatures in the mid 100s.
But the threat of dry thunderstorms and gusty winds prompted the National Weather Service in Salt Lake City to issue a Red Flag Warning for northwestern Utah from Wednesday afternoon into the evening. Meteorologists expected storms to develop statewide by the early afternoon, with the heaviest rain in central Utah and the possibility of flash flooding in dry washes and slot canyons.
The possibility for showers and thunderstorms persists into Thursday, with a forecast 20 percent chance of them across much of Utah.
The rains are not expected to do much to clean the air along the Wasatch Front, though. The Utah Division of Air Quality forecast only moderately healthy air for Weber, Davis, Salt Lake and Utah counties for Thursday. The rest of the state can expect healthy air, according to the division.
Allergy sufferers with a weakness for mold are not catching much of a break either. Intermountain Allergy & Asthma rated mold at a "high" level on its pollen index, with chenopods coming in at moderate.
Salt Lake City temperatures were forecast to reach 96 Thursday, followed by 97 on Friday; Ogden looked for 95 and 96 degrees, respectively; Provo 95 and 96; Logan 95 both days; Wendover 96 and 95; Duchesne 88 and 89; Cedar City 89 and 90; St. George 104 both days; and Moab 94 and 96 degrees.
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