The Biggest Snowstorm to Ever Hit Pennsylvania In the Month of October

Written by Ava Peluso
Published: October 17, 2023
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In most parts of Pennsylvania, the first snow doesn’t occur until November. October snow is normally limited to areas in the northwest of the state which have a higher elevation. However, there are exceptions to every rule, as eastern Pennsylvania received a record-breaking snowstorm on October 29, 2011.

Pennsylvania’s Wildlife During the Storm

ruffed grouse

Pennsylvania’s state bird, the ruffed grouse, thrives in snow.


The wildlife of Pennsylvania was most likely able to adapt to this unexpected storm. Animals in Pennsylvania have evolved to survive cold winter weather by migrating, hibernating, or simply tolerating the cold while they stay active.

Many animals can sense when a storm is coming and prepare accordingly. Most animals prepare for a storm by seeking shelter in hollow trees, thick vegetation, underground burrows, or crevasses in rocks. Some animals will also eat a lot before a storm to build up fat. The extra fat helps them keep warm and serves as reserves to live off of in case the storm prevents them from finding food later. Birds during snowstorms will stay in areas with a reliable food source. To stay warm, they use trees for shelter and puff up their feathers. When snow is on the ground, birds often congregate in areas where it tends to melt faster, such as roadsides, the edges of streams, and the bases of trees and shrubs.

Snow can even be helpful to certain animals. In winter, animals such as mice, voles, and even the ruffed grouse, Pennsylvania’s state bird, take shelter by burying themselves under the snow. The snow traps heat close to the ground, keeping the space underneath it warm. However, not all animals benefit from snow. The cold and lack of food make it more difficult for many wild animals to survive. This is especially true for species that recently expanded their range northward due to climate change. Since they have not adapted to cold weather, they struggle during unexpected bursts of cold and snow.

The Snowstorm of 2011


An unexpected nor’easter brought snow to Pennsylvania while it was still fall.


Pennsylvania’s October 2011 snowstorm began as a low-pressure area off the Carolina coast late at night on October 28. The following morning, it moved into the northeast of the United States, bringing heavy winds and precipitation. The precipitation began as rain in eastern Pennsylvania and parts of Delaware, New Jersey, and Maryland. In Pennsylvania and New Jersey, the temperature then dropped, causing the rain to change to snow by mid-morning. Other areas instead received sleet or continuing rain. The storm exited the region by mid to late evening, moving north into New England.

Impacts in Pennsylvania

Snowstorm, snow-covered street and cars with a lonely pedestrian

The October 2011 snowstorm caused road closures and transportation delays.


The parts of Pennsylvania that got the most snow were those with higher elevations. The Poconos, the Lehigh Valley, Berks County, and northwest New Jersey got eight to 16 inches of snow. The snow and strong winds caused extensive power lines and tree damage. The tree damage was more extensive because, at that time of year, most trees still had their leaves, and they couldn’t support the weight of both the leaves and the snow. The downed trees and power lines caused numerous road closures.

The damage created by the storm caused more than 1.7 million power outages across the states it affected, as well as transportation delays. In addition to road closings, dozens of flights were canceled, train service was suspended, and speed limits were reduced on bridges. Businesses felt the effects of the storm as people were prevented from traveling. There were also several fatalities in traffic accidents caused by slippery roads, and one fatality caused by a tree falling on a house.

The storm came at a busy time, taking place on a Saturday just two days before Halloween and during football season. Some activities were canceled due to the weather, but many Halloween festivities and professional and college football games were held in the snow.


Halloween finish.pumpkings under snow

A snowstorm on October 29 meant there was still snow on the ground on Halloween.


While the storm left the area after just one day, its effects lasted for several days afterward. Tree and power line damage took a while to be cleaned up or fixed, and snow remained on the ground. Snow still covered the ground on Halloween the following Monday, leading to children trick or treating in the snow. Some people chose to celebrate the holiday unusually by having snowball fights and building Halloween-themed snow sculptures.

While Pennsylvania recovered from the storm, other states still faced it. The heaviest snow took place late at night and into the following day in parts of Massachusetts, Connecticut, Vermont, and New Hampshire. The wind was especially strong in coastal areas, and some coastal areas experienced flooding as well.

Many Pennsylvania residents were surprised to receive any snow in October, let alone a storm as strong as this one. Before 2011, the last major snowstorm to hit Pennsylvania in October was in 1972. While the storm caused many problems, some people tried to make the best of it by participating in their favorite winter activities early.

The photo featured at the top of this post is © RHartley/

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About the Author

Ava Peluso is a writer at A-Z Animals where her focus is on wildlife and locally relevant topics. She has a Bachelor's degree in Communication from DeSales University, which she earned in 2021. She also has experience volunteering with animals and caring for numerous personal pets. A resident of Pennsylvania, Ava enjoys reading about animals and watching birds and other wildlife.

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