BETHLEHEM, Pa. — Asked to describe the weather pattern over the next few weeks, EPAWA meteorologist Bobby Martrich didn’t mince words with his response.
“It’s going to be loaded,” Martrich said Monday, describing an “overrunning pattern” that goes through mid-month and could potentially bring the Lehigh Valley no fewer than three or four storm chances before Valentine’s Day.
But there are a number of factors that will help the pattern turn volatile, and what happens this week will influence what happens next week, he said.
It starts Wednesday
“What’s happening this week is we’ll have a system arriving Wednesday night, and then there’s likely to be almost a carbon copy storm Saturday or Saturday night," Martrich said.
He described the setup of both systems as high pressure to our north providing another cold air damming scenario, allowing warm air to override colder air at the surface.
“Wednesday night’s system probably starts as snow, but then it’s going over to sleet and freezing rain. The good thing with this is that it’s not going to be catastrophic-type stuff,” Martrich said, describing precipitation through the event as about a half-inch of liquid total.
That means different precipitation types resulting in a wintry mess, but hopefully no power outages or other lingering issues.
“We’re going to have to figure out how much is going to be freezing rain,” Martrich said. “Models assume everything that’s falling on the ground is freezing, but it doesn’t work that way.”
He said the rule of thumb is to cut numbers on those models in half, and the goal over the next day or two is to see how much of that freezing rain is “stolen.”
“The longer it remains snow and sleet the better,” he said, with the idea the Lehigh Valley could see around a tenth of an inch of ice, or a number “on either side of that.”
“The longer it remains snow and sleet the better."Meteorologist Bobby Martrich on Wednesday's storm
We’ll likely repeat the same scenario “almost verbatim” this weekend, but it doesn’t look to interfere with Super Bowl parties on Sunday.
Martrich said precipitation should clear the area very early Sunday, if not before.
For its part, the National Weather Service also flagged "the possibility of winter weather headlines," this week, particularly if freezing rain also ends up as the dominant precipitation type.
What about next week?
“The whole premise of why this is happening is a thermal gradient boundary just to our south, then that advances,” Martrich said.
“So next week that boundary looks like it’s going to be a little bit further south. It moves south and that’s because next week we have some Greenland blocking in place. That forces the boundary south, and the storm track a little further south.”
Translation?
“When we get into any precipitation events it’s more likely to be snow or a longer period of it, at least,” Martrich said.
And the pattern is more active because of that boundary and where it’s setting up.
"When we get into any precipitation events it’s more likely to be snow or a longer period of it, at least."Meteorologist Bobby Martrich, on chances for snow next week
“In a La Nina, which we’re in now, the southeast ridge can be a make or break for winter,” Matrich said. “February 2021 had a similar setup, with a southeast ridge trying to push warmer air into the region, but blocking kept it just cold enough here. The storm track was active along that gradient and a lot of moisture from the Gulf to tap into. If you don’t have that blocking, that’s done.”
To that end, Martrich has pretty high confidence the two storms this week won’t miss.
Attention will then turn to the chance for snow next week.
