PHOENIX – After three weeks of unprecedentedly high temperatures, the series of record daily heat in Phoenix finally came to an end on Tuesday.

The temperature at Phoenix Sky Harbor International Airport, which the National Weather Service (NWS) uses for the city's official readings, reached a high of 99 degrees, below the Oct. 15 record of 103 degrees.

It was the first time since Sept. 24 that Phoenix failed to meet or break the daily heat record and the first day below 100 degrees since Sept. 22. Previously, the city had never achieved heat records for more than seven consecutive days.

“This is pretty unprecedented,” said Gabriel Lojero of the NWS in Phoenix KTAR News 92.3 FM on Tuesday morning.

After the record heat is reached, it's time to cool down

Not only is Phoenix no longer experiencing record heat and triple-digit temperatures for the time being, Arizona's capital is also experiencing truly autumnal weather for the first time this year.

Temperatures are expected to gradually cool for a few days, with highs still in the 90s, until a strong storm system moves across the Valle on Friday, Lojero said.

“The temperatures will continue to cool,” he said. “By Saturday we could have trouble reaching the 80 degree high temperature here in Phoenix. Most areas will likely stay in the 70s.”

Another series could be coming to an end soon. The system could bring Phoenix's first measurable rain since that day on August 22, a span of nearly two full months.

The best chance of rain will be on Friday. However, there will be no flood, said Lojero.

“We're not expecting heavy rainfall, just enough to wet the ground,” he said.

Jim Cross of KTAR News 92.3 FM contributed to this report.

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