Pennsylvania, 2021

Frost and Freeze in Pennsylvania, April 20 to 22, 2021

April 20 to 22, 2021 · NWS CLE · 1 event in 1 county or zone

Above normal temperatures in March and above normal to record high temperatures in early April in Northwest Pennsylvania allowed for area fruit crops to begin budding ahead of schedule in April. A low pressure system brought several rounds of snow to the region on April 20-21 and residual snow allowed for temperatures to cool considerably with low temperatures in the upper 20s to lower 30s into…

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.

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  • Heat and drought
  • Cold
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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
$3.0 million
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 CLE wrote it up.

Above normal temperatures in March and above normal to record high temperatures in early April in Northwest Pennsylvania allowed for area fruit crops to begin budding ahead of schedule in April. A low pressure system brought several rounds of snow to the region on April 20-21 and residual snow allowed for temperatures to cool considerably with low temperatures in the upper 20s to lower 30s into the morning of the 22nd. For area farmers, the combination of snow and cold damaged area grape crops in interior portions of Erie County, Pennsylvania. The area with the most damage was in portions of Harborcreek and North East Townships near Interstate 90. These vineyards were heavily damaged with an estimated 85 to 95% crop loss on the first shoots of grapes. In some areas, some of these first shoots were only slightly damaged but the second shoots of grapes were delayed after an unimpressive first batch of grapes. Local news reports relay that some of the area will have only half a grape crop for the year. Area apple and cherry crops were also damaged prompting smaller yields.

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 Cleveland, OH wrote its last area forecast discussion before the first event at Apr 20, 7:33 PM EST, 2 hours 27 minutes earlier.

Area forecast discussion, Apr 20, 7:33 PM EST, 2 hours 27 minutes before
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Hazardous weather outlook, Apr 20, 9:43 PM EST, 17 minutes before
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In the hours before

Local storm report, Apr 20, 7:45 PM EST, 2 hours 15 minutes before
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Local storm report, Apr 20, 9:16 PM EST, 44 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 frost/freeze. Local standard time, as filed.

Frost/Freeze, Southern Erie

When
April 20, 10:00 PM EST to April 22, 11:00 AM EST
Where
Southern Erie forecast zone
Crop damage
$3.0 million
Reported by
Newspaper
Coordinates
42.118, -80.098 (the zone’s center; the record gives no point)

Above normal temperatures in March and above normal to record high temperatures in early April in Northwest Pennsylvania allowed for area fruit crops to begin budding ahead of schedule in April. A low pressure system brought several rounds of snow to the region on April 20-21 and residual snow allowed for temperatures to cool considerably with low temperatures in the upper 20s to lower 30s into the morning of the 22nd. For area farmers, the combination of snow and cold damaged area grape crops in interior portions of Erie County, Pennsylvania. The area with the most damage was in portions of Harborcreek and North East Townships near Interstate 90. These vineyards were heavily damaged with an estimated 85 to 95% crop loss on the first shoots of grapes. In some areas, some of these first shoots were only slightly damaged but the second shoots of grapes were delayed after an unimpressive first batch of grapes. Local news reports relay that some of the area will have only half a grape crop for the year. Area apple and cherry crops were also damaged prompting smaller yields.

What these are

Frost/Freeze
Frost or temperatures at or below freezing during the growing season, usually filed for crop damage.

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

The same day elsewhere

More

Every storm in Pennsylvania in 2021Every state in 2021This day in weather historyWarnings in Pennsylvania, April 2021

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: 967925.