Heat in Delaware, June 7 to 9, 1999

Name: Heat in Delaware, June 7 to 9, 1999
Start: 1999-06-07T09:00
End: 1999-06-09T19:00
Location: Delaware

June 7 to 9, 1999 · NWS PHI · 4 events in 4 counties and zones

A large high pressure system over the southeastern United States pumped in a hot and humid air mass across the Delmarva Peninsula for three days. The hottest day was the 8th.

Where it happened

Every event with a place to put it; 4 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

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The toll

Deaths: 0
Injuries: 5
Property damage: None recorded
Crop damage: None recorded
Events: 4

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 PHI wrote it up.

A large high pressure system over the southeastern United States pumped in a hot and humid air mass across the Delmarva Peninsula for three days. The hottest day was the 8th. A weak trough brought in slightly cooler and considerably drier air on the 9th, although high temperatures still reached around 90 degrees. A stronger backdoor cold front (it moved from north to south) brought in considerably cooler air into the region the evening of the 9th. High temperatures reached 98 degrees in Milford (Kent/Sussex County Line) and Salisbury, MD, 97 degrees in Georgetown (Sussex County) and 94 degrees at the New Castle County Airport. There were five heat related illnesses reported in Wilmington on the 7th. Many schools in the state had early dismissals on the 8th. A fan drive was initiated for the elderly within Wilmington and the city's Department of Health and Social Service Division of Public Health issued safety and health related warnings. People were not the only ones to suffer, the Automobile Association of America (AAA) responded to about 180 calls of disabled vehicles throughout the state on the 7th.

The radar

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

Open the radar archive at this moment

Event by event

4 heat. Local standard time, as filed.

Heat, Inland Sussex

When: June 7, 9:00 AM EST to June 9, 7:00 PM EST
Where: Inland Sussex forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 38.683, -75.339 (the zone’s center; the record gives no point)

Heat, Kent

When: June 7, 9:00 AM EST to June 9, 7:00 PM EST
Where: Kent forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.096, -75.505 (the zone’s center; the record gives no point)

Heat, New Castle

When: June 7, 9:00 AM EST to June 9, 7:00 PM EST
Where: New Castle forecast zone
Injuries: 5 direct, 0 indirect
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.578, -75.639 (the zone’s center; the record gives no point)

Heat, Delaware Beaches

When: June 8, 9:00 AM EST to 7:00 PM EST
Where: Delaware Beaches forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 38.683, -75.339 (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.

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

The same day elsewhere

Every storm in Delaware in 1999 Every state in 1999 This day in weather history Warnings in Delaware, June 1999

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: 5703518, 5703594, 5703595, 5703517.