Pennsylvania Weather Highlights of 2025
Top 10 2025 Pennsylvania Weather Highlights
Time to countdown the most notable weather events that occurred in Pennsylvania during 2025. As usual, I do not rank them, but rather I will post them in chronological order.
Honorable Mentions
- Cold Memorial Day & end of May Coolest Memorial Day since 2003 for Erie. Windchills were in the 30s on the 31st!
- 3 tornadoes on June 9th EF2 in Erie County strongest tornado of 2025.
1st EF2+ in Erie County since 1997.
- Windy November, December Maybe it was just me, but it felt like the wind never stopped.
Most Wind Advisories ever issued for PA.
January 20-22 Coldest Temperatures in 10+ years
 |
| High temperatures ending 7am Jan 22 (left) and minimum temperatures ending 7am Jan 23 (right). |
During a cold & snowy January, a cold snap brought the coldest temperatures in over 10 years. Low temperatures for the majority of Pennsylvania dropped below zero on the mornings of the 21st, 22nd, and 23rd. High temperatures failed to rise out of the single digits and teens during the 3 day period.
 |
| Chart comparing the low temperatures on January 22nd with the last time temperatures were that cold. |
Temperatures on the morning of January 22 were the coldest temperatures that had been recorded in 10 years for much of the state. It was the coldest morning in 31 years for Altoona and Harrisburg! Temperatures touched the 50s on the last day of January but cold dominated with average temperatures for the month running generally 3° to 5° below average.
Sloppy February
A barrage of wintry weather brought rounds of tricky travel to the state during the second month of the year. Light freezing rain, sleet, and snow was observed on Groundhog Day. The second event on February 5-6 brought the first Ice Storm Warnings since 2022. The Ice storm Warnings were issued for the Laurel Highlands and surrounding areas while a Winter Weather Advisory covered the rest of the state. Following soon after another event with Ice Storm Warnings moved through on the 8th.
 |
| Highest freezing rain reports from numerous events during the month of February 2025. |
Two more mixed precipitation events would impact the state on the 12th-13th and again on 15th-16th. The last event ended with Blizzard Warnings in the Laurel Highlands and High Wind Warnings across central and eastern Pennsylvania. A quarter inch of ice was reported somewhere in the state on four different days in Feburary.
 |
| Some webcam images showing the ice accretions from February 9th (left) and February 6th (right). |
March 16 Squall Line & Tornadoes
 |
| Map summarizing the severe weather on March 16, 2025. |
A line of severe storms brought widespread wind damage to the western half of Pennsylvania the day before Saint Patrick's Day. 25 Severe Thunderstorm Warnings and 10 Tornado Warnings were issued along the line. The Latrobe airport recorded an 89mph wind gust! At 5pm, over 180,000 customers were without power in the state. Hail up to 1.75" was also reported in Westmoreland County.
 |
| Webcam images of the approaching shelf cloud from Connellsville (left) and Bentleyville (right) on March 16th. |
After days of storm surveys, seven tornadoes and many downbursts were confirmed. All of the tornadoes were rated EF1. This was the second most tornadoes in Pennsylvania for the month of March behind 1978 when 8 tornadoes were recorded.
April 29 Derecho
 |
| Map of the severe weather reports and warnings from April 29, 2025. |
A derecho brought another round of widespread wind damage to much of the same area impacted by the event on March 16. Widespread trees and powerlines were blown down, along with roofs blown off buildings. A cell phone tower was blown over and a barn collapsed in Cambria County. Windows were blown out of a skyscraper in Pittsburgh. Once again the Latrobe Airport recorded the strongest wind, a 79mph gust.
 |
| Power outage map from 7:51pm on April 29th (left) and a radar image of the derecho at 5:56pm (right). |
At the peak, 580,000 customers were without power. Allegheny County was hit hard with 250,000 of those outages. The recovery was slow with 300,000 outages remaining 24 hours later. It would take 6 days for nearly all of the power to be restored.
June Heat
 |
| Charts summarizing record high temperatures on June 23 and 24. |
The last full week of June brought record heat & humidity to the state. Record high temperatures were broken across much of the state on the 23rd and 24th in the midst of a 4-5 day heatwave. Record warm low temperatures were also broken the 22nd through 25th.
 |
| 24 hour high temperatures ending 8am on June 25. |
101° in Philadelphia on June 24th is the 2nd hottest June temperature on record. Additionally, the low that day was 80° which was the warmest June low temperature since 1952. With dewpoints in the 70s, heat index values soared over 100° in eastern Pennsylvania and it was one of the most humid Junes on record for some locations.
Months of Flash Flooding May-July
Following a very dry start to the year, May brought soggy conditions, ranking as the 2nd wettest May on record for Pennsylvania. It was the wettest May on record for Altoona and Harrisburg. Lingering drought conditions from 2024 were finally erased by June. Given that the ground was so dry leading up to May, flooding was not a major issue as it would be in the months to follow. One flood event on May 13th in southern Somerset County was impactful. Flash flooding resulted in evacuations and water rescues in Somerset, Meyersdale, and Salisbury. A bridge along Route 219 was also washed out.
 |
| Total precipitation (left) and departure (right) for May-July 2025. |
The wet May set the stage for more flooding in June and July. Even though it wasn't an overly wet period, when it rained it came in downpours. There were 36 Flash Flood Warnings in May (2nd most for May), 94 in June (3rd most for June), and 97 in July (record most for July). Flash Flood Warnings were issued on 18 different days in June. A Flash Flood Emergency was issued on the evening of June 30th for portions of Lancaster County and extreme southern Lebanon County where over 4 inches fell in less than 24 hours. On July 31st, a Mesonet site site in Reading picked up 3.32" in 42 minutes.
 |
| All Flash Flood Warnings from May (left), June (center), and July (right). |
August Flash Drought
 |
| Summary of stations that recorded stretches of at least 12 days without measurable precipitation. |
Following a wet May and June, precipitation was a bit more spotty in July. By the end of the month, a dry stretch was beginning for parts of the state. Starting on July 27th, some locations did not record any precipitation for 17 days! It wasn't long for drought conditions to develop, making for another fall season with drought (though not as severe as fall 2024).
 |
| Drought Monitor timeseries for 2025 showing the drought improvement in June with a flash drought beginning in August. |
On August 5th, none of Pennsylvania was in any drought category. At the start of September, over half of the state was in Abnormally Dry conditions or Moderate Drought. At the start of October 98% of the state was classified in at least Abnormally Dry conditions and Severe Drought had been introduced in southwestern PA. The dry conditions also allowed for cooler temperatures at the end of August with the earliest Frost Advisories on record in the state.
Wetness Along Lake Erie in October
While October was dry for the majority of the state and drought continued to expand, the area closest to the Lake Erie observed a very wet October with a firehose coming off Lake Erie. 2.22" fell in Erie on October 7th which was the wettest day of the year until 2.51" fell on the 23rd pushing the total over 7" for the month. With an additional 1.65" on the 30th, the month ended with a total of 9.04", ranking as the 2nd wettest October on record and the 8th wettest month ever!
 |
| Accumulated precipitation for Erie for the month of October 2025 (green line) compared to the wettest October on record, 1954 (pink). |
Some more crazy stats about the wetness in Erie:
- The last October day with more than 2.00" was in 1988.
- October 2025 is the first time with 2 days with more than 2.00" during the month of October.
- The last time (and only other time) that 3 days with 1.50"+ of rain was recorded in October was 1885!
- October 23rd ranks as the 4th wettest October day ever (2.51"); October 7th ranks as 7th wettest (2.22").
 |
| Bluesky post I made summarizing the wettest months on record for Erie. |
Cold First Half of December
The month of December started off with impressive cold. Average temperatures through the first 15 days of the month were 7° to nearly 14° below average across the state. This ranked as a top 10 coldest first half of December on record and was the coldest since in 20+ years for most of the state.
 |
| Chart detailing the cold weather for the first half of December 2025. |
Along with the cold temperatures, above average snowfall was observed. While the second half of the month brought warmer temperatures, the cold start locked in a colder than average December statewide and the coldest December in 10 years.
Icy Christmas Travel
It may be because it is fresh in my memory but the ice storm the day after Christmas stands out to me. Some light icing occurred on the morning of the 23rd, causing schools to begin the winter break early, but the biggest weather disruption came on the 26th.
 |
| Webcam images from Altoona showing the ice on December 26. |
Ice Storm Warnings were issued for portions of central & western PA with almost all of the remaining portions of the state under a Winter Weather Advisory or Winter Storm Warning. It was the first time Ice Storm Warnings had ever been issued for Erie and Crawford Counties and the first since 2007 for many other counties. Sleet & freezing rain caused many accidents and road closures. Over a quarter inch of ice accretion was observed in the central mountains. There was thunder sleet and thunder freezing rain observed, too!
 |
| Highest freezing rain reports on December 26. |
Wrapping Up
This is the second of three posts that will look at the weather in Pennsylvania for 2025. Make sure to check out my previous post reviewing the severe weather this year. Before the third 2025 review, I will post the December monthly review in coming days.
Thanks for reading and remember to always look up!
Comments
Post a Comment