National Weather Service United States Department of Commerce

Dangerous Heat Builds and Expands; Critical Fire Weather for the Southwest; Severe Thunderstorms for Plains and Midwest

Dangerous to record breaking heat will build across the center of the nation and slowly build eastward this week. Wildfire conditions remain critical for the Southwest and portions of the Great Basin through Monday. For the northern Plains and upper Midwest, severe thunderstorms with the potential for large to very large hail and severe winds are the primary hazards. Read More >

Images/Maps of the forecast elements (temperature, wind, etc.) are available via this link.

Forecaster's
Discussion:

County-by-County
Forecast:

Daily Co-operative Station
Observation Summary:

Public Information
Statement:

 

All NWS State College Text Statements/Forecasts:

 

Latest PA Weather Summary:


116
AWUS81 KCTP 012102
RWSCTP
PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-
049>053-056>059-063>066-021115-

Regional Weather Summary
National Weather Service State College PA
502 PM EDT Wed Jul 1 2026

Strong high pressure at the surface and aloft will allow the
strong early summer sun to bake the region for the next few days.
Humidity levels more commonly found in the tropics will settle
over Pennsylvania and result in oppressive days and uncomfortable
nights. Heat advisories and Extreme Heat Warnings continue for
the next few days. Afternoon high temperatures will top the
century mark over the southeast portion of the state, with
nighttime lows in the low to mid 70s.

Isolated showers and thunderstorms will dot northeast
Pennsylvania through the evening hours. These storms may provide
some brief relief from the heat, but could come with strong wind
gusts.

It will remain muggy through the night with nighttime lows in the
70s. Unseasonable heat and humidity will continue through Friday
with heat advisories and extreme heat warnings continue through
the end of the week.

Take steps to protect yourself from heat related illness. Drink
plenty of fluids and refrain from doing any strenuous activity in
the sun during the peak heat of the day. Stay in air conditioned
areas as much as possible. Local municipalities and counties may
have cooling stations operating where people without air
conditioning can visit for temporary relief from the heat. Power
outages are also possible when the demand for electricity becomes
high due to the widespread need to use air conditioning.

$$


Latest Forecaster's Discussion:


827
FXUS61 KCTP 020149
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
949 PM EDT Wed Jul 1 2026

.WHAT HAS CHANGED...
* Bumped PoPs up for isold-sct SHRA/TSRA this PM in the north/east
* Expanded the Heat Advisory into Somerset County into Thursday
* Expanded the Extreme Heat Warning into Bedford, Fulton, and
Blair Counties into Thursday

&&

.KEY MESSAGES...
1) Significant, long duration, and dangerous heat wave expected
for the rest of the week, and into Independence Day for the
southeastern cities.

&&

.DISCUSSION...
KEY MESSAGE 1: Significant, long duration, and dangerous heat
wave expected for the rest of the week, and into Independence
Day for the southeastern cities.

Not of lot of change this evening. Risk of storms and showers
has been mainly to the east and north of central PA all day.
With the loss of heating and trends on the radar as of mid
evening, the chance of anything should continue to trend down
overnight.

The interesting issue is the amt of dry air just above the
surface just to the west noted on observed soundings. Dewpoints
could drop off on Thursday, making it feel a bit better in that
regard. However, the decrease in dewpoints could result in it
being warmer than it would be otherwise.

More information below.

Surface dewpoints are remaining elevated even as peak daytime
heating begins early this afternoon. Drier air is struggling to
mix down to the surface and as a result high heat index values
are being observed even in the higher terrain. This has prompted
the expansion of the both the Heat Advisory and Extreme Heat
Warning for this afternoon and tomorrow. The messaging will
remain the same over the next few days for dangerous heat
impacting all of Central Pennsylvania.

The big upper ridge and the sfc high will be in place for today
and Thursday. Starting on Friday, the upper ridge gets a little
less-strong, and the sfc pressure pattern gets a little muddied.
Clouds and better chances for SHRA/TSRA will ensue. That should
help nudge temps down. While we will still be in a general
ridge, the sfc pressure dips a bit and a baroclinic zone slowly
dips in from the north. By Sunday, the flow aloft is zonal with
the baroclinic zone parallel to the flow aloft (W-E) providing a
focus SHRA/TSRA for the end of the weekend and into next week.
Time will tell if we will be under the gun for any flash
flooding worries Sun and beyond.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
High pressure at the surface and aloft which is delivering
unseasonable heat and humidity will expand and center more
closely to Pennsylvania over the next 48 hours.

This will push any ridge-edge convection further north and east
of Pennsylvania Thursday and Friday. Good VFR will prevail at
all locations through the forecast period. Winds will remain
generally light with just isolated areas (20%) topping 10 knots
during the afternoon hours.

Biggest concern will be density altitude over the next two days.
High resolution short term models forecast dewpoints to drop
overnight and then fall into the 50s during the afternoon
Thursday. This should keep any widespread fog from forming
overnight (<10%), but will help surface temperatures climb a
few degrees higher than today. If you`re flying on the heavy
side and/or taking off from a runway on the shorter side, double
check that value and its effect on your performance.

Outlook...

Fri-Sat...Patchy AM fog; otherwise VFR. Hot & humid with PM
t-storms psbl. High density altitude concerns possible.

Sun...Restrictions possible in afternoon t-storms

Mon...Restrictions possible in afternoon t-storms

&&

.CLIMATE...
Bradford reached 89 degrees this afternoon, breaking the old
record of 88 degrees set in 1963.

Earlier information below.

Triple digit max temps are forecast in the Lower Susq Valley
(LSV) on Thursday and Friday bookended by upper 90s today and
Saturday.

The last time Harrisburg observed consecutive days with maxT
greater than or equal to 100F was back in 2011 on July 21-22.

The record number of consecutive days with maxT >= 100F is 3
and has occurred 5 times: (all in the month of July)

1999-07-16 to 1999-07-18
1999-07-04 to 1999-07-06
1991-07-19 to 1991-07-21
1966-07-02 to 1966-07-04
1936-07-09 to 1936-07-11

The last time Harrisburg hit the century mark was July 16th in
2024. Prior to that, it was July 19th in 2020.

Harrisburg averages 1 day annually with a maxT >100F. The most
number of days observed in a year is 6 in 1999.

The record maxes for the next few days are in jeopardy:

Station/Date...07/01...07/02...07/03...07/04...07/05.
MDT.............100.....104.....107.....104.....102..
IPT.............102......99.....100.....100.....100..
AOO..............94......97......97......97......94..
JST..............98......98.....100.....100.....101..
BFD..............88......90......91......91......91..

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM EDT Friday for PAZ004>006-010>012-017-
018-024-037-041-042.
Extreme Heat Warning until 8 PM EDT Friday for PAZ019-026>028-
036-045-046-049>053-056>059-063>066.
Heat Advisory from 8 PM Friday to 8 PM EDT Saturday for PAZ019-
026>028-036-045-046-049>053-056>059-063>066.
Extreme Heat Warning until 8 PM EDT Thursday for PAZ025-034-
035.
Heat Advisory from 8 PM Thursday to 8 PM EDT Friday for PAZ025-
034-035.
Heat Advisory until 8 PM EDT Thursday for PAZ033.

&&

$$

WHAT HAS CHANGED...Dangelo/Martin/Bowen
KEY MESSAGES...Dangelo/Martin
DISCUSSION...Dangelo/Martin/Bowen
AVIATION...Tyburski
CLIMATE...Dangelo/Steinbugl/Martin


Latest Public Information Statement:


875
NOUS41 KCTP 261315
PNSCTP
PAZ057-030400-

Public Information Statement
National Weather Service State College PA
915 AM EDT Fri Jun 26 2026

...NOAA WEATHER RADIO ALL HAZARDS STATION IN HARRISBURG...

NOAA Weather Radio All Hazards Station WXL-40, located in
Harrisburg, PA may experience intermittent outages over
the next several days.

We are aware of the issue and hope to have fixed soon.

We apologize for the inconvenience.

$$