www.weather.gov/media/ctp/DssPacket.pdf

Dangerous Heat Possible Midweek

Issued: July 12, 2026, at 5:33 AM EDT by the National Weather Service (State College, PA)

Overview

Heat and humidity are expected to increase from Tuesday into Wednesday as high pressure builds to the southwest. Heat index values over 100°F are possible, particularly in the Lower Susquehanna Valley on Wednesday.

Timing & Location

• Peak Heat: Wednesday afternoon and early evening.
• Hotspot: The Susquehanna Valley is showing the strongest signal for heat index values of 100°F or higher.

Hazards & Impacts

• Dangerous heat may lead to heat exhaustion, especially for individuals without proper hydration or those undertaking strenuous activity.

NWS Alerts

• Status: None at this time.

Forecast Challenges

• There is uncertainty regarding exactly how hot and humid Wednesday afternoon will be. This depends on the timing of a cold front to the north.

Post-Event Outlook

• The weather pattern late this week into the weekend may be conducive to rounds of thunderstorms, some of which could produce strong wind gusts.

Next Briefing

• Scheduled for 6 AM Monday.

Max Heat Index Forecast (Wednesday, July 15, 2026)

The map indicates the following forecasted heat index values for various locations:

• 100°F+: Harrisburg, Lancaster, York, Mifflintown
• 96°F - 99°F: State College, Lock Haven, Williamsport, Selinsgrove, Bloomsburg, Altoona, Clearfield, Emporium
• 91°F - 95°F: Warren, Ridgway, Coudersport, Wellsboro, Laporte, Johnstown, Somerset, Bedford, Chambersburg
• 87°F - 90°F: Bradford

Note: The forecast max heat index may still change by a few to several degrees in the coming days. Residents are advised to monitor subsequent forecasts for the latest information.