Extreme Heat Warning for San Diego County Inland Valleys

Source: NOAA · San Diego County Inland Valleys

This alert is no longer in effect.

NOAA issued it on September 9, 2026, 12 days ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).

Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.

An Extreme Heat Warning is in effect for San Diego County Inland Valleys until 8 PM PDT September 9, with dangerously hot conditions and high temperatures up to 107 expected.

Read this weather record in 30 seconds

Record type
Extreme Heat Warning
Affected area
San Diego County Inland Valleys
Issued
September 9, 2026
Issuing authority
NWS San Diego CA

Heat notices are time-bound and location-specific. Confirm the current forecast and local public-health guidance before relying on this archived record.

Record status: historical. It was issued 12 days ago; use the issuing agency's live warning service for current conditions in San Diego County Inland Valleys.

Alert Details

Extreme Heat Warning issued by NWS San Diego CA. Effective from 2026-09-09T02:58:00-07:00 until 2026-09-09T20:00:00-07:00. Severity: Severe. Certainty: Likely. Urgency: Expected.

Affected Areas

San Diego County Inland Valleys (San Diego County Valleys).

What You Should Do

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

Expected Conditions

Dangerously hot conditions with high temperatures in the mid 90s to 107 and low temperatures in the 70s expected. Major to Extreme HeatRisk. Warm overnight temperatures will limit relief from the heat. Heat related illnesses increase significantly during extreme heat events.

Timeline

Alert effective starting 2026-09-09T02:58:00-07:00 and ends 2026-09-09T20:00:00-07:00.

Original source: NOAA Official Notice ↗

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Nationwide notices with similar length or severity timing 8

Two cross-category peer sets, both computed from Areazine's own archive: notices with a similar body length, and notices near the same severity and agency date. These are drawn from other categories, not the same-feed Related list above.

Common Questions

What people usually ask about a notice like this one.

What is this NWS weather alert about?
An Extreme Heat Warning is in effect for San Diego County Inland Valleys until 8 PM PDT September 9, with dangerously hot conditions and high temperatures up to 107 expected.
Which agency issued this alert?
This alert was issued by NOAA. The original notice is available at the source link at the bottom of this article.
How severe is this alert?
This alert is classified as "high" severity. Take precautions and monitor for updates.
What area is affected?
This alert affects San Diego County Inland Valleys. Check with NOAA for the most current geographic scope.
Where can I find more Weather Alerts updates?
Browse the full Weather Alerts feed on Areazine at areazine.com/weather/ for the latest updates from NOAA and other agencies.