BETHLEHEM, Pa. — An impactful storm arrived with sleet and freezing rain in the Lehigh Valley on Thursday, but it’s the back end of the system on Friday that’s a bigger concern for the area.
One of the main worries with the system will be a flash freeze potential due to an arctic front racing into the area.
- The Lehigh Valley is under a flood watch from Thursday evening through Friday evening
- An arctic front racing into the area will send temperatures plummeting
- A flash freeze is likely Friday
The same front was making its way from the Pacific Northwest through the central U.S. on Wednesday, where the temperature dropped 40 degrees in just 30 minutes in Cheyenne, Wyoming.
From 1:05 p.m. to 1:35 p.m., the temperature plunged from 43 to 3 degrees in Cheyenne, the National Weather Service said on Twitter. It shattered the previous one-hour temperature drop record of 37 degrees for the area.
“This is a very powerful system that will impact the eastern 2/3rds of the contiguous US,” the weather service office in Mount Holly, N.J., warned in its own tweet.
The same arctic front which will race through our area on Friday is currently making its way across the central US, where the temperature dropped 40° in just 30 mins this afternoon. This is a very powerful system that will impact the eastern 2/3rds of the contiguous US. https://t.co/e2zBFO9tVf
— NWS Mount Holly (@NWS_MountHolly) December 21, 2022
The Lehigh Valley is under a flood watch from Thursday evening through Friday evening, and the weather service said flooding from excessive rainfall continues to be possible, especially from creeks, streams, and other low-lying and flood-prone areas.
Rain could change to snow mid-to-late morning Friday just before the arctic front comes rushing through.
The Lehigh Valley is expected to see a rapid temperature drop in under two hours, causing a flash freeze with all wet surfaces turning to ice, including roads.
It will also be very windy and extremely cold, forecasters warn, with 15 to 25 mph sustained winds, and gusts 35 to 45 mph through Friday evening.
Overnight and Saturday through mid-to-late afternoon, we’ll continue to see occasional gusts of 35 to 40 mph until diminishing from Saturday evening onward.
PPL Electric Utilities said in an email Thursday morning it will have more than 2,000 employees and workers from peer utilities standing by and prepared to support power outage restoration efforts across the region.
It also reminded residents to stay away from downed power lines and call 800-342-5775 to report those issues.
"The only thing you can really say about this period is ... COLD," the Mount Holly forecast discussion said.
"This is an air mass the likes of which we haven’t seen for several years," the discussion continued. "With highs likely staying colder than they`ve been since January and February of 2019, it's the coldest air we`ve seen in almost four years."
Wind chills across the Poconos will drop toward minus -20, while the Lehigh Valley could see wind chills around minus -10.
State officials are urging Pennsylvanians to pay attention and remain alert for rapidly changing conditions and brutal cold this holiday weekend.
“Many people are traveling to spend time with friends and family this weekend, so it’s important to know the forecast for your home, your destination and points along your intended travel route,” said Pennsylvania Emergency Management Agency Director Randy Padfield in a news release.
“We can’t control the weather, but we each can control how informed and prepared we are, so that we can make decisions that keep our loved ones safe,” Padfield said.
PennDOT said it has been pre-treating roads to help prevent ice from forming a bond with the pavement during the early stages of the storm. However, it will be a race to treat many areas after the rain ends and the flash freeze begins.
Roads that look wet may actually be icy, and extra caution will be needed when approaching bridges and highway ramps where ice can form without warning.
Officials urge travelers to pack an emergency kit for their car. It should contain a flashlight with fresh batteries, jumper cables, first aid supplies, blankets, a cell phone charger, bottled water and non-perishable food items.
Families who must travel with infants or pets should also consider extra formula or pet food, officials say.
Thousands of flights have already been canceled across the country, and Delta, American, United, Frontier, Alaska, Southwest and other airlines are waiving change fees and offering travelers the option of choosing new flights to avoid the bad weather, the Associated Press reported.
The storm is impacting more than 100 million people across the U.S. that are under winter weather and wind chill alerts.
The weather service is calling the storm a “once in a generation type event.”
