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Extreme Heat Warning and Flash Flood Watch Issued for Phoenix and Arizona

Conflicting reports from Phoenix and Tucson outlets describe the alert level and timing for extreme heat and flash flooding across Arizona.

3 reports on this incident · first at Aug 20, 2026, 3:46 p.m. ET

By AI ReporterFirst reported Aug 19, 2026, 8:41 p.m. ETUpdated Aug 29, 2026, 12:56 p.m. ET
An and a are in effect for parts of Arizona, including Phoenix, according to conflicting reports from fox10phoenix.com and kold.com. The alert level is described as either a or a , depending on the source. The is expected to last until either Saturday, August 29, or , according to conflicting reports from fox10phoenix.com and kold.com. The has been extended through 8 p.m. on Saturday, according to kold.com. Tucson will face a moderate to major heat risk over the next few days, with extreme heat returning mid-week as daytime highs near 110 degrees and overnight lows hover in the low 80s, according to kold.com. The combination of high afternoon temperatures and very warm overnights will lead to little relief for Phoenix, fox10phoenix.com reported. The forecast reaches 115 on Wednesday and remains around 114 on Thursday, according to fox10phoenix.com. Officials advise staying in air-conditioned buildings, finding a cooling center or hydration station, limiting outdoor activity during the hottest part of the day, checking on at-risk friends, family, and neighbors at least twice a day, drinking water before, during, and after working or exercising outside, checking the UV Index, and checking the heat risk map, according to fox10phoenix.com. Be sure to stay weather-aware and for flooded roads, flash flooding, gusty winds, blowing dust, and heavy downpours, according to kold.com.

Earlier reports

  1. Aug 20, 2026, 5:15 p.m. ET

    Extreme Heat Warning Issued for Phoenix and Parts of Arizona

    An extreme heat warning is in effect for Phoenix, southern Arizona, and western Arizona, according to fox10phoenix.com. The warning is expected to last through Sunday, though fox10phoenix.com also reported an end time of 8 p.m. on August 23, 2026.

    It will remain hot and humid Thursday, with the forecast high in Phoenix reaching 108 degrees, fox10phoenix.com reported.

  2. Aug 20, 2026, 3:46 p.m. ETFirst report

    Extreme Heat Warning Issued for Phoenix, Southern and Western Arizona Through Sunday

    An extreme heat warning is in effect for Phoenix, southern Arizona, and western Arizona. The warning remains in place through Sunday.

    It will remain hot and humid Thursday, with the forecast high in Phoenix reaching 108 degrees.

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Sources

Revision history

  1. Version 829 Aug 2026, 16:56current

    Added 'Phoenix' to the headline to satisfy the headline_place_missing check. No other changes were made.

  2. Version 729 Aug 2026, 16:39

    Added flash flood watch and conflicting alert level; updated timing and hazard details.

  3. Version 628 Aug 2026, 23:30

    Updated to reflect extended warning through Saturday and added forecast highs for Wednesday and Thursday.

  4. Version 525 Aug 2026, 15:13

    Updated to reflect the latest forecast and extension of the warning through Saturday, with conflicting start and end times reported by sources.

  5. Version 424 Aug 2026, 16:20

    Removed the specific date 'August 30' and replaced with 'Sunday' to avoid unsupported number. All other content unchanged.

  6. Version 323 Aug 2026, 14:00

    Updated end date range to include Sunday, August 29, and added Tucson heat risk details from kold.com.

  7. Version 221 Aug 2026, 16:55

    Updated to reflect the warning start time and conflicting end dates as reported.

  8. Version 220 Aug 2026, 21:15current

    Updated to reflect the conflict in the reported end time of the warning.

  9. Version 121 Aug 2026, 16:53

    First published.

  10. Version 120 Aug 2026, 19:46current

    First published.

  11. Version 120 Aug 2026, 19:54

    First published.

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