We’d like to take the time to discuss something that you may, or may not, already know about Pennsylvania.
Pennsylvania has what is called a bimodal fire season – this
means that we have two separate fire seasons. A common thought is that fire
season is summertime, and this could be attributed to all the coverage of fires
in the Western part of our nation – which occur mainly in the summer.
Our nation has several different times for fire seasons. Fire season characteristics are driven by seasonal and
continental-scale weather patterns, their movement, and variation. Seasonal air
mass and jet stream changes affect various regions at different times and in
different ways. In Pennsylvania, our problem times are in the spring (March
through May) and fall (October through November), the Great Lakes, Northeast
and Southeast all have similar patterns – unlike the rest of the nation having
a “summer” fire season. However, our Spring season can extend well into summer
if the jet stream remains active and brings windy/dry events that are preceded
by dry conditions of two weeks or more. Much like what we saw at the end of
Spring into early Summer.
We have previously discussed why the Spring is our primary fire season, with a flare up again in the fall. But just as a refresher, or if this is your first visit here, we will touch on it again. The typical pattern experienced east of the Rockies is a frequent occurrence of dry, or nearly dry, cold frontal passages over a somewhat long timeframe. This is the main mean of drying for our fuels, especially in the winter/early spring and fall. Why? Because we have deciduous trees here in good ol’ PA and they drop their leaves, allowing for a big open canopy. This means the sun can heat up the forest floor much easier than in the late spring and summer, along with limited shelter from the wind. The saving grace lies in how much snowpack we had over the winter. If we had a decent amount, all the litter and duff will be compacted and harder to dry out. On the flip side if we have a winter like we just did, where we had very little snow, the litter will still be all fluffy and easy to dry out. Thankfully, the front patterns are less likely to occur in the summer here, plus our trees are nice and green – keeping those canopies shaded.
This year we saw two large, difficult
fires: the largest to note was the Crystal Lake fire that started on Wednesday, April 12, 2023, and was 100% contained on Sunday, April 16, 2023. That incident
happened near Mountain Top, Luzerne County in the Pinchot State Forest. The
Crystal Lake fire burned 4319 acres and did result in a temporary closure of
the Pennsylvania Turnpike’s Northeast Extension. The Crystal Lake fire was
caused by incendiary devices. There was also the Pool Hollow fire, near Sandy
Ridge, Centre County which burned 1,445 acres. That fire started Thursday, April
20, 2023, and was 100% contained on Saturday, April 22, 2023. Pool Hollow was
started due to equipment use.
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