MOST ACCURATE FORECAST: High clouds move in, but monsoon storm chances stay low

20 Sep 2026, 23:56 by Iris Hermosillo · ABC15 Arizona

PHOENIX — High clouds are moving in but monsoon storm chances will be limited as we head into the new week.

Storms will be hard to come by for the next few days, with only a slight chance of isolated showers and thunderstorms in far southern and southeast Arizona on Sunday and Monday.

Temperatures will climb into the upper 90s to low 100s each afternoon, putting highs near normal in the Valley.

Mornings will feel comfortable, with lows dropping into the upper 70s to low 80s each day.

As an area of low pressure approaches from the west, we'll see a boost in monsoon moisture and an uptick in storm chances across northern and eastern Arizona starting Tuesday.

Storms could pop up in areas near the Valley by Tuesday afternoon, but there's only a very slight chance of a stray storm in the Valley that day.

Valley storm chances will climb again later in the week and during the final weekend of September, but stay tuned for updates as we get closer.

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2026 Sky Harbor Rainfall to-date: 2.07" (-3.11" from average)

2026 Monsoon Rainfall to-date: 1.75" (-0.49" from average)

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Daily rainfall reports from all across the Valley can be found here.

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PHOENIX IS GETTING DRIER - LOWER RAINFALL AVERAGES NOW