A Winter Weather Pattern Worth Watching

October 14, 2022

If you’re like me, you follow weather patterns for hints of what’s to come.

We all know that predicting the weather can be an inexact science, but this should not deter us from following the long-range trends emerging in our skies and seas. After all, a season of heavy snowfall or a bitterly cold winter have ramifications for our emergency preparedness, and I’ve always believed that early information is power when it comes to our situational awareness.

If you’re interested in knowing more about the upcoming winter weather, I have some clues to share with you.

The ‘rare’ triple-dip La Niña

First, weather aficionados will tell you that we may see our first “triple-dip La Niña” of the century this winter, and it offers some useful information for all the weather watchers out there.

A “La Niña” refers to a weather pattern in the Pacific Ocean that helps drive forecasts globally. With La Niña events, strong trade winds push warm water toward Asia, setting off a chain of events in the rest of the world.

This year would mark our third “La Niña” winter in a row, creating a so-called “triple-dip La Niña”.

“La Niña” means “the little girl” in Spanish, and generally causes the opposite effects when compared to “El Niño” (the little boy) climate patterns. During La Niña seasons, the jet stream shifts northward, basically right over Pennsylvania or just north of it. Anything south of the jet stream will see warmer air, thus causing winters to be mild with less snow.

A volcanic-sized caveat

A word of caution: this season may be unique and the forecast could be complicated due to multiple factors. Generally, no La Niña season is the same, so uncertainty looms.

Secondly, an underwater volcanic eruption in the island nation of Tonga on January 15 could alter our forecasts. This eruption was so massive that it emitted huge amounts of water vapor into the atmosphere. This could result in warmer temperatures for the next few years.

As always, when it comes to the weather, it’s best to look for clues—not promises.

Down to the numbers

Several reputable weather services already have released their forecasts for winter 2022–2023. All of them show a similar trend: a cold blast to start the season with some possible snowfall events, and then warming through January and February.

Overall it looks to be an above average temperature season here in the northeast and a below-average snowfall season. As for snowfall predictions, according to AccuWeather:           

• Philadelphia could see between 14 and 20 inches of snowfall compared to the average of 23 inches.
• Pittsburgh is projected to receive 40 to 45 inches of snow, which is close to the season’s average of 44.1 inches.

What do we make of these figures? We need to keep in mind that these are predictions, mostly using experimental modeling and historical data. These estimates can change, and we need to continually monitor weekly forecasts for the best information to act on.

The bottom line

If you haven’t already, now is a good time to review your winter weather plans. Also, consider reviewing your mass casualty incident (MCI) plan, especially for hospitals close to major highways. Snow squalls have been increasing and have caused multiple large MCIs due to vehicle accidents in recent years.            

Simply put, our long-range weather outlook does not provide any guarantees, but it does help emergency managers—and our teams—prepare for what’s to come.

For questions about your winter weather or MCI plans, contact me or HAP’s Emergency Management team for more information.