California, 2023

Excessive Heat in California, August 16 to 17, 2023

August 16 to 17, 2023 · NWS PSR · 6 events in 6 counties and zones

An upper level ridge of high pressure strengthened over the Intermountain West going into the latter part of August, leading to excessive heat conditions across parts of southeast California. Any heat-associated fatalities that may have occurred during this event are unknown.

Where it happened

Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
6

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PSR wrote it up.

An upper level ridge of high pressure strengthened over the Intermountain West going into the latter part of August, leading to excessive heat conditions across parts of southeast California. Any heat-associated fatalities that may have occurred during this event are unknown.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Phoenix, AZ wrote its last area forecast discussion before the first event at Aug 16, 4:26 AM PST, 4 hours 34 minutes earlier.

Area forecast discussion, Aug 16, 4:26 AM PST, 4 hours 34 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

6 excessive heat. Local standard time, as filed.

Excessive Heat, Imperial County Southwest

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Imperial County Southwest forecast zone
Reported by
County Official
Coordinates
33.040, -115.365 (the zone’s center; the record gives no point)

Excessive Heat, Salton Sea

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Salton Sea forecast zone
Reported by
County Official
Coordinates
33.392, -115.679 (the zone’s center; the record gives no point)

Excessive Heat, Imperial County West

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Imperial County West forecast zone
Reported by
County Official
Coordinates
33.040, -115.365 (the zone’s center; the record gives no point)

Excessive Heat, Imperial Valley

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Imperial Valley forecast zone
Reported by
County Official
Coordinates
33.040, -115.365 (the zone’s center; the record gives no point)

Excessive Heat, Palo Verde Valley

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Palo Verde Valley forecast zone
Reported by
County Official
Coordinates
33.392, -115.679 (the zone’s center; the record gives no point)

Excessive Heat, Chuckwalla Valley

When
August 16, 9:00 AM PST to August 17, 7:00 PM PST
Where
Chuckwalla Valley forecast zone
Reported by
County Official
Coordinates
33.744, -115.994 (the zone’s center; the record gives no point)

What these are

Excessive Heat
Heat at or above the local excessive heat warning criteria, or heat that caused deaths.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in California in 2023Every state in 2023This day in weather historyWarnings in California, August 2023

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1218120, 1218121, 1218122, 1218123, 1218124, 1218125.