textproduct: State College

WHAT HAS CHANGED

* Wildfire smoke from Ontario, Canada and Minnesota will trigger code red/orange air quality alerts for Thursday and Friday * Added chance of locally heavy rainfall Saturday

KEY MESSAGES

1) A few damaging wind gusts or instances of hail may occur over the next few hours across east-central PA

2) Hot temperatures and risk of heat related impacts peak this afternoon

3) Wildfire smoke from Ontario, Canada and Minnesota will trigger code red and orange air quality alerts Thursday and Friday

4) Thunderstorms with potential for locally heavy rainfall to start the weekend followed by cooling trend next week

DISCUSSION

KEY MESSAGE 1: A few damaging wind gusts or instances of hail may occur over the next few hours across east-central PA

Radar trends indicate somewhat vigorous convective development over northeast PA on the leading edge of thick belt of smoke moving southward from NY. SPC just issued MCD #1626 for this area indicating brief wind/hail potential and unlikely watch issuance (20%).

KEY MESSAGE 2: Hot temperatures and risk of heat related impacts peak this afternoon

IPT, MDT, LNS, SEG, CXY, THV, and RVL have eclipsed the century mark for max heat index so far today. MDT most likely to challenge daily record high based on 19Z observations.

KEY MESSAGE 3: Wildfire smoke from Ontario, Canada and Minnesota will trigger code red and orange air quality alerts Thursday and Friday

Visible satellite loop shows wildfire smoke plume entering northern PA this afternoon. The smoke will spread from north to south through tonight and trigger air quality alerts for Thursday and Friday.

The PA Department of Environmental Protection (DEP) has issued statewide code red and orange air quality alert for Thursday and Friday, July 16-17th.

KEY MESSAGE 4: Thunderstorms with potential for locally heavy rainfall to start the weekend followed by cooling trend next week

Thunderstorms are expected Saturday and could produce locally heavy rainfall and isolated flash flooding. PW values are forecast to reach the 1.5-2.0" range which suggests intense rain rates will be possible. The second half of the weekend looks dry on Sunday. Additional bouts of rain/t-storms are possible into the workweek with unsettled conditions. Temperatures will trend near to below historical averages through late week with some noticeable cooler nights possible.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

Looking at largely VFR conditions into this evening.

An isolated shower or storm could form, but left out of the TAFS, given low potential. The airmass is quite warm aloft, so not a lot of support for much in the way of shower and storm formation.

Smoke from fires up in Canada will be across the area through Thursday. At this time the smoke is mainly elevated. For the TAFS I did bring some smoke later tonight into Thursday. I did not bring visibilities down real low at this time.

Outlook...

Fri AM...Mainly VFR, with areas of late night/AM fog. Some reduced visibility possible from smoke, with an isolated late- day SHRA/TSRA possible.

Fri PM-Sun...Chance of showers and t-storms, mainly during the afternoon hours on Saturday into early Sunday aft.

Mon...Partial clearing.

CLIMATE

Daily record high max temperatures for July 15th _______________________ SITE | RECORD/YEAR | ----------------------- MDT | 99/2024 | ----------------------- IPT | 103/1995 | ----------------------- AOO | 98/1995 | ----------------------- BFD | 88/2013 | ----------------------- STCP1 | 97/1887 | -----------------------

CTP WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 8 PM EDT this evening for PAZ019-026>028- 035-036-045-046-049>053-056>059-063>066.