Updated every Sunday before noon. Because the weather doesn’t take weekends off, and apparently neither do we.

Sunday, August 23rd, 2026 — Summer hasn't left the building, but somebody finally showed it where the exit is.

If you walked outside this weekend and wondered who turned off August, you're not imagining things.

We've moved into a noticeably cooler pattern across South Central Pennsylvania, and the next several days will continue running below what we'd normally expect for late August. Highs generally in the upper 70s to lower 80s are favored through the early part of this week, with some areas struggling to escape the 70s. That's several degrees below normal for this point in the calendar.

Before anyone starts decorating the porch: this is not fall.

The SCPAWX Pumpkin Embargo remains in effect.

We'll discuss parole after Labor Day.

August actually spent much of its first three weeks running warmer than average. Through August 21st, most areas were roughly +0.5°F to +4°F above average. This cooler finish should knock those departures back down, leaving August as a whole near average, roughly -1°F to +1°F.

Late this week, temperatures begin recovering. August 26th-27th should trend near to slightly below average before August 28th-31st returns near to slightly above average. So no, summer isn't packing the moving truck. It's just taking a few personal days.

Rainfall has also become a much different story than it was earlier this summer.

Repeated rounds of beneficial rain have continued improving drought conditions across portions of the region. The latest outlook now projects August to finish slightly wetter than average, around +0.5" to +1.0" across the region as a whole.

That's a pretty substantial turnaround from the dry conditions we were talking about earlier this summer. The drought isn't erased everywhere, particularly farther southeast, but the atmosphere finally started paying some of its overdue water bill.

For the immediate future, today's cold front brings at least an isolated opportunity for showers or thunderstorms. After that, the next organized precipitation opportunity arrives with another cold front around Thursday.

Then things start getting interesting.

Breakdown of precipitation departures over the next several weeks:

August 22 – August 28: Slightly above average. Recent rainfall plus additional opportunities help finish August on the wetter side.

August 29 – September 4: Near to slightly below average. The faucet starts tightening.

September 5 – September 11: Near to slightly below average. No strong signal for widespread soaking rainfall.

September 12 – September 18: Near to slightly below average. The drier September pattern continues.

September 19 – September 25: Slightly below average. September apparently forgets everything August just learned.

September 26 – October 2: Slightly below average. The dry lean continues through the end of September.

September as a whole is now projected to finish slightly below average for precipitation, around -0.5" to -1.0". Temperatures, meanwhile, are projected near to slightly above average, 0°F to +2°F.
Remember what "above average" means in September, though.

The averages themselves are falling quickly. Around Harrisburg, the average high drops to approximately 82°F by September 1st, 78°F by September 15th and 72°F by October 1st. A +2°F temperature departure in late September isn't summer refusing to leave. It's a 76-degree afternoon instead of 74.

Nobody needs to alert the National Guard.

There is, however, something new appearing farther down the road.

While it's not an official projection yet, seasonal trends and several longer-range climate models are beginning to suggest October could turn much wetter than average. That's nowhere near enough confidence to start making specific October forecasts, but it's our first signal worth putting on the board.

For now: September dry lean. October wetter signal.

We'll see whether that survives the next several weeks of guidance before promoting it from "interesting" to "something we're buying."

The Madden-Julian Oscillation isn't offering much help right now. The MJO has collapsed into the Circle of Death/NULL phase and is expected to remain there for the foreseeable future. That leaves the broader El Niño background state and other teleconnections doing most of the heavy lifting.

And El Niño continues getting stronger.

As of August 20th, Niño 4 sits around +1.1°C, Niño 3.4 has climbed to +2.7°C, Niño 3 is +3.3°C, and Niño 1+2 remains an impressive +3.8°C.

We're firmly in moderate-to-strong El Niño territory. The current event is also East-based, and the expectation remains that our El Niño summer transitions into a strong El Niño fall.

That's also worth watching as we approach the climatological peak of Atlantic hurricane season around September 10th. Strong El Niño conditions increase Atlantic wind shear, and the current outlook continues to favor limited Atlantic tropical activity despite approaching the historical peak of the season.

And yes, before somebody asks: I'm already watching what all of this could mean for winter.

But El Niño alone does not tell us whether South Central Pennsylvania gets buried in snow, watches rain at 34 degrees all winter, or spends January arguing about ice. Even historically, El Niño's relationship with Harrisburg snowfall isn't straightforward. We'll need to see how several other pieces of the atmospheric puzzle evolve this fall before making that call.

In short: August is going out considerably more comfortably than it came in.

We've moved into a cooler stretch through early this week before temperatures gradually recover toward the end of August. Rainfall has improved enough that August should finish slightly wetter than average, while drought conditions continue slowly improving.

September currently looks somewhat warmer and drier than average, while way out on the horizon October is beginning to throw us a wetter signal worth monitoring.

Bottom Line:

Enjoy this.

Seriously.

Open the windows when the humidity cooperates. Sit outside. Give the AC compressor a chance to remember what silence sounds like. We have reached the point of the year where average temperatures are heading downhill, daylight is disappearing, and the climatological hottest part of summer is officially behind us.

But summer isn't dead.

Late August temperatures rebound, September still has plenty of opportunities to remind us that Pennsylvania owns humidity, and above-average temperatures remain possible again during portions of September.

So yes, Carla, you may move the pumpkin decorations closer to the attic door.

You may NOT deploy them.

SCPAWX Pumpkin Embargo remains in effect.

When significant weather threatens South Central Pennsylvania, get the latest timing, impacts and live alerts at SCPAWX Weather Alerts — because "it looked fine when I left the house" remains Pennsylvania's unofficial emergency preparedness plan.

What This Means for You

Summer hasn't surrendered. But somebody finally found the thermostat.

Upper 70s and lower 80s in late August?

Yep.

We're running slightly below average through the early part of this week, and some areas may spend a good chunk of the day stuck in the 70s. That's several degrees below normal for late August.

Before Facebook gets carried away:

IT IS NOT FALL.

Pumpkin deployment remains unauthorized.

August is trying to balance the books.

Most areas were running roughly +0.5°F to +4°F above average through August 21st. This cooler finish should pull the monthly numbers back down enough for August to finish near average overall, around -1°F to +1°F.

Late next week, temperatures recover toward average and eventually near to slightly above average.

Translation: Don't uninstall the air conditioner.

Rainfall finally completed remedial training.

August is now projected to finish slightly wetter than average, +0.5" to +1.0".

Repeated beneficial rainfall has helped improve drought conditions across portions of the region, although the remaining drought farther southeast isn't completely gone yet.

Unfortunately, September apparently skipped the class.

Breakdown by week:

August 22 – August 28: Slightly above average rainfall. August finishes wetter.

August 29 – September 4: Near to slightly below average.

September 5 – September 11: Near to slightly below average.

September 12 – September 18: Near to slightly below average.

September 19 – September 25: Slightly below average.

September 26 – October 2: Slightly below average.

September: Slightly below-average precipitation, roughly -0.5" to -1.0".

Temperature-wise, September currently favors near to slightly above average, 0°F to +2°F.

But remember: September averages are already dropping. "Above average" doesn't automatically mean 90 degrees and swamp butt.
October just walked into the briefing room.

This is NOT an official projection yet, so nobody start carving this into stone.

But several seasonal climate models and broader trends are beginning to suggest October could be much wetter than average.

Interesting?

Absolutely.

Forecast?

Not yet.

The MJO went AWOL.

It's collapsed into the Circle of Death/NULL phase, leaving El Niño and the other teleconnections in charge of the pattern for a while.

And El Niño apparently found the weight room.

Niño 3.4: +2.7°C

Niño 3: +3.3°C

Niño 1+2: +3.8°C

We're firmly in moderate-to-strong El Niño territory, it's currently East-based, and a strong El Niño fall remains favored.

Yes, that gets our attention heading toward winter.

No, we're not issuing a snowfall forecast in August.

We've suffered enough as a society.

Bottom Line:

Cooler now.

Warmer again toward the end of August.

September leans somewhat warmer and drier.

October is flashing an early wetter signal.

And El Niño continues sitting at the head of the conference table.

Enjoy the comfortable temperatures while they're here. Open the windows, give the AC some liberty, and enjoy being outside without immediately becoming one with the humidity.

As for fall decorations?

The SCPAWX Pumpkin Embargo has been downgraded from Warning to Watch.

Conditions are becoming favorable for pumpkin deployment sometime in the next few weeks.

No action is required at this time.