Connecticut, 2025

Excessive Heat and Heat in Connecticut, June 22 to 25, 2025

June 22 to 25, 2025 · NWS ALY · 7 events in 2 counties and zones

A dome of high pressure brought a period of very hot and humid conditions across northwestern Connecticut from June 22-25, 2025. Peak heat index values (or feels-like temperatures) were between 95 and 104 degrees Fahrenheit in many locations.

Where it happened

Every event with a place to put it; 7 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
7

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 ALY wrote it up.

A dome of high pressure brought a period of very hot and humid conditions across northwestern Connecticut from June 22-25, 2025. Peak heat index values (or feels-like temperatures) were between 95 and 104 degrees Fahrenheit in many locations. The highest heat index values (feels-like temperatures) occurred on June 23 with values between 105 and 110 degrees Fahrenheit. Preliminary data from the U.S. Health and Human Services showed that eight-year records for one day heat-related emergency department visits were set during this heat wave across region 1 which included all of Connecticut and the rest of New England. This period of hot weather also prompted the Connecticut Governor to activate the state's extreme hot weather protocol.

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 Albany, NY wrote its last area forecast discussion before the first event at Jun 22, 9:14 AM EST, 46 minutes earlier.

Area forecast discussion, Jun 22, 9:14 AM EST, 46 minutes before
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In the hours before

Special weather statement, Jun 22, 7:40 AM EST, 2 hours 20 minutes before
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Local storm report, Jun 22, 9:58 AM EST, 2 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

5 heat, 2 excessive heat. Local standard time, as filed.

Heat, Northern Litchfield

When
June 22, 10:00 AM EST to 7:00 PM EST
Where
Northern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Heat, Southern Litchfield

When
June 22, 10:00 AM EST to 7:00 PM EST
Where
Southern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Excessive Heat, Northern Litchfield

When
June 23, 10:00 AM EST to 7:00 PM EST
Where
Northern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Excessive Heat, Southern Litchfield

When
June 23, 10:00 AM EST to June 24, 7:00 PM EST
Where
Southern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Heat, Northern Litchfield

When
June 24, 10:00 AM EST to 7:00 PM EST
Where
Northern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Heat, Northern Litchfield

When
June 25, 10:00 AM EST to 6:00 PM EST
Where
Northern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

Heat, Southern Litchfield

When
June 25, 10:00 AM EST to 6:00 PM EST
Where
Southern Litchfield forecast zone
Reported by
Mesonet
Coordinates
41.847, -73.221 (the zone’s center; the record gives no point)

What these are

Heat
Heat below excessive heat criteria that still caused deaths, injuries or significant impacts.
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 Connecticut in 2025Every state in 2025This day in weather historyWarnings in Connecticut, June 2025

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: 1274373, 1274374, 1274379, 1274380, 1274375, 1274377, 1274378.