Phoenix started Monday with light rain and temperatures around 88 degrees, but the brief monsoon interruption is expected to fade by sunrise. After that, the city faces a dangerous run of heat, with afternoon temperatures climbing above 110 degrees nearly every day through Saturday.
The National Weather Service in Phoenix forecasts a partly sunny Monday with a high near 108 degrees and heat index values up to 110. Winds should remain light, generally below 5 mph, as the last early-morning showers move out.
Tuesday Through Thursday Look Brutal
Tuesday is expected to reach 113 degrees, followed by a forecast high of 116 on Wednesday and 113 on Thursday. Overnight lows will only fall to about 89 to 91 degrees, offering little relief after sunset, while forecasters say the middle of the week could approach or challenge daily heat records.
An Extreme Heat Warning is in effect across the Phoenix metropolitan area through 8 p.m. Saturday, August 29. Officials warn that the conditions can increase the risk of heat cramps, heat exhaustion and potentially fatal heat stroke, especially for people working or exercising outdoors.
Rain Chances Nearly Vanish Before Returning
Rain chances drop below 10% beginning Tuesday and are expected to remain very limited through Thursday as drier air settles over the Valley. A few showers or thunderstorms could return Friday night and expand into the lower deserts over the weekend, with Sunday carrying a 20% chance of precipitation.
Even Sunday’s forecast high of 107 degrees will still be hazardous, though it would mark a modest break from the week’s worst heat. Winds may increase slightly to 5 to 10 mph Saturday and Sunday, but not enough to provide meaningful cooling.
Outdoor Plans Need A Rethink
People who must work outside should schedule strenuous tasks for early morning or evening, take frequent breaks in shade or air conditioning, wear loose lightweight clothing and drink plenty of water. Maricopa County advises residents to call 2-1-1 for information about free cooling centers, transportation and water assistance.
Anyone showing signs of heat stroke should be moved to a cool, shaded place and treated as an emergency by calling 911. With multiple days above 110 degrees ahead, the safest forecast may be the one that keeps you indoors during the afternoon.
