Happy Meteorological Fall!By Katie Fehlinger

By Katie Fehlinger

PHILADELPHIA (CBS) — If you follow the astronomical calendar, the season technically doesn’t begin until the Autumnal Equinox on September 22nd (at 10:29 PM to be specific).

However, we meteorologists tend to track the seasons by climatic changes. Between the months of September and November, we see more fall-like shifts in our weather pattern, typically including things like more activity in the tropics and an increase in pushes of cooler air from Canada (though those have been plentiful this summer!)

Interestingly, the next 5 days will likely be the hottest stretch we’ve seen in Philadelphia since mid-July. Here’s what’s up:

A large dome of high pressure offshore is sending a very warm, moisture-rich air mass our way, allowing not just a spike in temperatures (low 90’s and upper 80’s Labor Day afternoon), but also soaring humidity levels. By Tuesday, a cold front will cross late in the day to at least help wipe out the humidity. However, it won’t cool us down all that much. We keep the upper 80’s right through the end of the week.

Monday/Tuesday Storms

While I don’t expect a washout, you may need to briefly delay your pool, beach, or barbecue plans Monday afternoon or evening as a scattered variety of showers or storms rumbles through.

Tuesday brings a similar forecast, and any wet weather may hold off until the evening since we’ll be awaiting the leading edge of our cold front.

Brighter by Wednesday

High pressure will regain control by Wednesday to bring back the sunshine, and though we’ll get a respite from the worst of the humidity, we only see a modest drop on the thermometer. Temperatures will continue to soar well into the upper 80’s Wednesday through Friday.

Happy Labor Day!

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