Thursday expected to be hottest day of the year, so far

You just have to walk outside to feel the difference.

Thursday morning is much hotter and muggier than Wednesday and Philadelphia didn't even get below 70 degrees overnight. That's 14 degrees warmer than this time Wednesday. We may even be in for a heat wave.

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FOX 29's Sue Serio reports hot air is coming in from the southwest. That should continue until Friday afternoon. (Click planner for map and heat wave information.)

Thursday, dress for the summer and wear sunscreen if you're going to be out for long. Dew points in the 60s confirm it's muggy. There's also an air quality alert out for pollution.

The high temperature is expected to be 94, which would tie the record set in 1962. It's also 15-20 degrees above average.

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Thursday night, expect a muggy low of 71.

As of now, Friday's high temperature is expected to be 89, but that'll depend on when that hot air coming in from the southwest stops. If we do make it a degree warmer to 90, then we'd have three straight days of 90 or above, giving us our year's first heat wave.

Wednesday, Philadelphia made it up to 91 degrees - hot but not the 92 needed for a record set in 1974.

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After that, expect a cooler weekend.