Pennsylvania, 2009

Winter Weather in Pennsylvania, December 31, 2009

December 31, 2009 · NWS PHI · 8 events in 8 counties and zones

An approaching cold front and leftover moisture in the area gave the region a second round of wintry weather during the evening of the 31st and the early morning of January 1st. Snow mainly fell in the Lehigh Valley and the Poconos where additional accumulations were an inch or less.

Where it happened

Every event with a place to put it; 5 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
0
Property damage
None recorded
Crop damage
None recorded
Events
8

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.

An approaching cold front and leftover moisture in the area gave the region a second round of wintry weather during the evening of the 31st and the early morning of January 1st. Snow mainly fell in the Lehigh Valley and the Poconos where additional accumulations were an inch or less. In Berks County and the Philadelphia northwest suburbs, a wintry mix of mainly sleet and freezing rain fell. Ice accretions were less than one tenth of an inch, but any untreated walkways and roadways were hazardous. The precipitation spread from south to north between 6 p.m. and 8 p.m. EST on the 31st and ended between 1 a.m. and 5 a.m. EST on January 1st.

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 Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Dec 31, 3:09 PM EST, 2 hours 51 minutes earlier.

Area forecast discussion, Dec 31, 3:09 PM EST, 2 hours 51 minutes before
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Hazardous weather outlook, Dec 31, 11:27 AM EST, 6 hours 33 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

8 winter weather. Local standard time, as filed.

Winter Weather, Montgomery

When
December 31, 6:00 PM EST to 11:59 PM EST
Where
Montgomery forecast zone
Reported by
Trained Spotter

Winter Weather, Chester

When
December 31, 6:00 PM EST to 11:59 PM EST
Where
Chester forecast zone
Reported by
Trained Spotter

Winter Weather, Bucks

When
December 31, 6:30 PM EST to 11:59 PM EST
Where
Bucks forecast zone
Reported by
Trained Spotter

Winter Weather, Berks

When
December 31, 7:00 PM EST to 11:59 PM EST
Where
Berks forecast zone
Reported by
Trained Spotter
Coordinates
40.416, -75.926 (the zone’s center; the record gives no point)

Winter Weather, Lehigh

When
December 31, 7:00 PM EST to 11:59 PM EST
Where
Lehigh forecast zone
Reported by
Trained Spotter
Coordinates
40.613, -75.592 (the zone’s center; the record gives no point)

Winter Weather, Northampton

When
December 31, 7:00 PM EST to 11:59 PM EST
Where
Northampton forecast zone
Reported by
Trained Spotter
Coordinates
40.754, -75.307 (the zone’s center; the record gives no point)

Winter Weather, Monroe

When
December 31, 8:00 PM EST to 11:59 PM EST
Where
Monroe forecast zone
Reported by
Trained Spotter
Coordinates
41.058, -75.339 (the zone’s center; the record gives no point)

Winter Weather, Carbon

When
December 31, 8:00 PM EST to 11:59 PM EST
Where
Carbon forecast zone
Reported by
Trained Spotter
Coordinates
40.918, -75.709 (the zone’s center; the record gives no point)

What these are

Winter Weather
Snow, sleet or freezing rain below warning levels that still caused disruption, damage or casualties.

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

The same day elsewhere

More

Every storm in Pennsylvania in 2009Every state in 2009This day in weather historyWarnings in Pennsylvania, December 2009

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: 205989, 205990, 205987, 205984, 205985, 205986, 205991, 205992.