The Baltimore City mesonet site just reached 100°. The Bittinger location, located at ~2,600 ft ASL in Garrett County, is on pace for an all time record high.
Even Allentown (ABE), Ft. Indiantown (MUI), and Wilkes-Barre (AVP) are making a run at 100°.
EDIT: Ft. Indiantown (MUI) just reported 101° on the 6hr ob!
Reading, Harrisburg (MDT* & CXY), and Lancaster all hit 100°.
*MDT hitting 100° before 2:00 pm is rare. According to the IEM bot page it's only happened twice in record keeping, both in July of 1991.
Not surprising that PHL to NYC are going gangbusters on heat. You're on the northern periphery of a strengthening mid level ridge in early July. Max heat advection.
The Edgewood mesonet site, located in Harford County, just came in at 95/81, producing a heat index of 117°. The 117° reading is a new network wide record for the mesonet.