Summer Heat Makes An Early Arrival

PHILADELPHIA (CBS) - When the cooler temperatures were the story in March and April, all you could hear across the region was "I can't wait for it to warm up."

Well, all of you who wanted the warmer weather, you are getting your wish, as summer-like temperatures and record-breaking heat are taking over the forecast starting today and the high heat will likely persist through Friday before we start a slowly cooling trend into the weekend and then next week too.

This afternoon we are going to watch the mercury rise into the lower 90s as an area of high pressure to the south just continues to funnel in warm and now humid air. While the heat index values today are not going to push into the dangerous range, it will still be extremely uncomfortable outside. Records across the region today from Delaware to Trenton and even into parts of the Lehigh Valley are likely to be challenged, and with a forecast high of 91 in Philly today, we are looking at breaking the old record of 90 set in 2001.

This heat, while record-breaking, is also very uncommon for the start of May. While it is not the earliest we have ever seen a 90-degree day in Philly, it is the earliest 90 degrees since 2009. On average, we don't see the first 90 degrees in Philadelphia until the end of the month. May 29 is the average first day for 90 in the city.

The heat is going to hang on for one more day on Friday as we climb into the upper 80s and possibly 90s again on Friday afternoon. Our high temperature in Philly tomorrow is going to be 89 which would be just shy of the record of 91 set in 2001. Humidity will be a factor for us once more tomorrow before a front will sweep through the region over the weekend and cooler and much less humid air will then filter in behind it. The more seasonable temperatures come at a price, though, with rain showers or a thunderstorm a possibility starting tonight in areas north of the city, and those shower chances lingering through Sunday night.

Have a great Thursday and make sure to stay cool out there today and tomorrow.