Colorado, 2023

Excessive Heat in Colorado, July 17, 2023

July 17, 2023 · NWS GJT · 1 event in 1 county or zone

A strong ridge of high pressure dominated the Desert Southwest for several days before its axis moved directly over the Western Slope. This led to scorching heat across the desert valley floors under sunny skies with humidities dropping into the single digits to low teens.

Where it happened

Every event with a place to put it; 1 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
1

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 GJT wrote it up.

A strong ridge of high pressure dominated the Desert Southwest for several days before its axis moved directly over the Western Slope. This led to scorching heat across the desert valley floors under sunny skies with humidities dropping into the single digits to low teens.

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 Grand Junction, CO wrote its last area forecast discussion before the first event at Jul 16, 4:45 PM MST, 18 hours 15 minutes earlier.

Area forecast discussion, Jul 16, 4:45 PM MST, 18 hours 15 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

1 excessive heat. Local standard time, as filed.

Excessive Heat, Grand Valley

When
July 17, 11:00 AM MST to 8:00 PM MST
Where
Grand Valley forecast zone
Reported by
ASOS
Coordinates
39.308, -108.185 (the zone’s center; the record gives no point)

High temperatures of 100 to 110 degrees were reported by various automated weather stations across the Grand Valley. The Grand Junction Regional Airport set a new record high temperature for the day of 107 degrees. This also tied the all time record high for the airport. Heat indices exceeded 100 degrees during the afternoon.

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 Colorado in 2023Every state in 2023This day in weather historyWarnings in Colorado, July 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 2026-10-01. Each event’s entry at NCEI: 1102009.