Record warm night
The overnight low, 74, was two degrees warmer than the record for the date.
Officially, this isn't likely to become the season's first heat wave; it just feels that way.
At Philadelphia International Airport it didn't get below 74 this morning, and if that stands as the low temperature for the day; the old record-high minimum for May 29 is 72.
The caveat is that a strong thunderstorms could drop the temperature in a hurry, said Walter Drag, meteorologist at the National Weather Service in Mount Holly, and they will be prowling the area late this afternoon and this evening.
Once again the weather service has an "excessive heat warning" in effect for the region, with heat indices expected to crest past the warning threshold of 96.
Yesterday's index actually came up 1 degree short of the early-season threashold, with a peak reading of 95. "I hope people aren't complaining about it," said Drag.
The warning trigger is set at 96 before mid-June, since people usually aren't ready to stew in heat and humidity in May.
The weather service is calling this a "hot spell." Technically, a heat wave requires three consecutive days of 90-plus temperatures.
At the airport it didn't get past 88 on Sunday. The high yesterday was 91, and it should make it to 93 before the storms rumble through today, but it will be back in the 80s tomrrow.
Terminology aside, sources inform us that it's been quiet uncomfortably hot.