Central PA Summer 2026 Discussion/Obs Thread

[mahantango#1]

10 hours ago, Itstrainingtime said:

Well, if loving when it's below zero with a 25 mph wind makes me mentally ill, I'm the poster child. This weather can go to hell. It already feels like it.

[mahantango#1]

US National Weather Service State College PA 

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530 AM Saturday June 13th, 2026: Enjoy today with lots of sun and lower humidity than in recent days. There is potential for more strong to severe storms on Sunday, mainly during the afternoon into the evening. The main threat will be strong winds and heavy downpours.

[pawatch]

57 degrees for the low this morning.

Blue bird sky.

[Mount Joy Snowman]

Low of 64 and man do things feel better out today. Last baseball game for the boy today and then a mow. All eyes on tomorrow. Also, what a performance by the USA men’s team last night. 

[ChescoWx]

Several degrees cooler today and much less humid. Highs will still be several degrees above normal levels. Much more humid again tomorrow before a strong cold front crosses the area tomorrow night. We should see temperatures falling back below normal both Monday and Tuesday before we warm up again toward the end of the week. Shower chances increase tomorrow afternoon into the evening with the cold front.

[canderson]

Thankfully for the less humidity! 
 

I don’t love tomorrow’s setup. 

[ChescoWx]

Here in Chester County PA most spots have seen an above normal amount of 90+ days so far this season. Below are the number so far this season by station along with the average per typical season along with the most and least by station. You can clearly see how relative elevation across our area impacts the number of such days. Also below you can see our average annual number of 90+ days is showing a clear reduction in number as we compare past decades to the 2020's.

[Superstorm]

Thankfully for the less humidity! 
 
I don’t love tomorrow’s setup. 

Yeah, could be wicked.


.

[Itstrainingtime]

From what I read on CTP's discussion this morning, an extremely rare day 6 outlook for central PA next Thursday.

[Superstorm]

From what I read on CTP's discussion this morning, an extremely rare day 6 outlook for central PA next Thursday.

El Niño


.

[canderson]

We are just obliterating average temps this June.  

[Yardstickgozinya]

3 hours ago, Itstrainingtime said:

From what I read on CTP's discussion this morning, an extremely rare day 6 outlook for central PA next Thursday.

ZCZC SPCSWOD48 ALL
   ACUS48 KWNS 130753
   SPC AC 130753

   Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0253 AM CDT Sat Jun 13 2026

   Valid 161200Z - 211200Z

   ...DISCUSSION...
   ...Days 5-6/Wed-Thu -- Lower MO/Mid-MS Valley to Ohio Valley and
   Mid-Atlantic...

   An upper trough is forecast to deepen over the Upper Midwest/Great
   Lakes on Wednesday. As this occurs, an intensifying 500 mb jet
   streak will develop across the central Plains and increase to 80-100
   kt as it moves into the Mid-MS Valley Wednesday night, and spreads
   eastward across the Ohio Valley and Northeast on Thursday. 

   At the surface, low pressure will develop over the northern/central
   Plains late Tuesday night into early Wednesday. As this occurs,
   increasing southerly low-level flow will quickly transport rich Gulf
   moisture northward into the Lower MO/Mid-MS Valley by Wednesday
   afternoon as the surface low moves across IA and a trailing cold
   front moves eastward in tandem with the low across portions of the
   central Plains and Mid-MS Valley. Strong to extreme instability is
   forecast across the strongly sheared warm sector. An all-hazards
   severe thunderstorm event appears likely. An intense southwesterly
   low-level jet is expected to develop during the evening. This could
   support upscale growth into an MCS moving across portions of the
   Midwest Wednesday night, posing a risk for swaths of damaging winds.

   This system will spread east on Thursday across parts of the Ohio
   Valley into the Mid-Atlantic/Northeast. A continued risk for all
   severe hazards, and possible MCS with damaging winds, will persist
   as the mid/upper jet streak is forecast to remain quite strong as it
   overspreads a seasonally moist airmass.

   While some timing differences of aforementioned features is evident
   in various NWP guidance, overall medium range consensus and mean
   calibrated ML/AI guidance suggests a multi-day severe episode is
   likely as this system overspreads portions of the Midwest to the
   Mid-Atlantic/Northeast, though the 15 percent risk areas may shift
   in the coming days as details become better resolved, and higher
   probabilities are possible in subsequent outlooks. The southern
   extent of severe potential is more uncertain across parts of the
   Plains toward the TN Valley as these areas will remain further
   removed from stronger flow aloft

[Yardstickgozinya]

    There are some questions about tomorrow's setup, the big one, being the possible lack of instability. What started off looking like could be an anomalous storm season for cpa fell off a cliff quick. Instability and weak capping has been about as hard to come by the spring, as any of i've seen. That said, we all know big shifts are taking place right now so let's see what happens. Seems like we're moving in the right direction for increased convection opportunities and most importantly precipitation. 

[Yardstickgozinya]

Not that anybody probably cares, but I got so far behind in work and life I decided to drop the forum for a while and until I got caught up. 

[Itstrainingtime]

24 minutes ago, Yardstickgozinya said:

Not that anybody probably cares, but I got so far behind in work and life I decided to drop the forum for a while and until I got caught up. 

I've been posting far less than usual. Different reasons but I understand why you did what you did.

[Itstrainingtime]

28 minutes ago, Yardstickgozinya said:

    There are some questions about tomorrow's setup, the big one, being the possible lack of instability. What started off looking like could be an anomalous storm season for cpa fell off a cliff quick. Instability and weak capping has been about as hard to come by the spring, as any of i've seen. That said, we all know big shifts are taking place right now so let's see what happens. Seems like we're moving in the right direction for increased convection opportunities and most importantly precipitation. 

NAM had very scattered activity during the late afternoon and evening followed by a squall line around midnight that was weakening by that point.

I want rain but not the severe. 

[mahantango#1]

7 minutes ago, Itstrainingtime said:

NAM had very scattered activity during the late afternoon and evening followed by a squall line around midnight that was weakening by that point.

I want rain but not the severe. 

So some of us might not get anything.

[Yardstickgozinya]

8 hours ago, Itstrainingtime said:

I've been posting far less than usual. Different reasons but I understand why you did what you did.

It's not unusual for me to step away for work and play, tis the season.

  When it comes to any kind of digital media less is better, so good for you. The concrete reality is, that there's a million different better and healthier ways you can spend  time than being online. It's bad for the body and mind.I don't think thst there was any coincidence to the fact that I spent three weeks  laid up with bodily injury early this spring. after leading the post count by a large margin, just a few weeks prior. The older I get, the more I notice a correlation between sedentary behavior and emotional and physical discomfort. 

That said, you're an integral part of this forum and an OG and it wouldn't be the same without you. 

 

[Yardstickgozinya]

Thursday is looking particularly interesting and it's truly worth keeping an eye on. Keyword elevated mixed layer. That's the main dynamic  that  keeps us safe out here east of the mighty mississipp and why we almost never see the big outbreaks the central and western united states sees. If it truly surges out ahead, this  absolutely could be one for the record books. Contrary to popular belief It's not the mountains, the ocean breeze or lack of unmodified gulf air, thst prevents Central and Western type outbreaks from occurring this far east .  EML lag is the true culprit.  if we have the EML we're capable of achieving  Central and Western United States type indices ,including those gargantuan fat capes in excess of 4000jkg that the MA/NE only see every thirty to forty years. 

[pawatch]

57 degrees this morning.

Lets see what the day brings.

[Yardstickgozinya]

If you dont believe me, then maybe you'll believe the american meteorological society. 

 

https://journals.ametsoc.org/view/journals/wefo/25/4/2010waf2222363_1.xml

[Mount Joy Snowman]

Low of 65. Looks like any real action down this way may not occur until after sundown. Then comes the relief, setting up a beautiful couple of days. 

[ChescoWx]

Much more humid today before a strong cold front crosses later this evening. The best chances for thunderstorms and rain will be between 8pm and 11pm across the area. Tomorrow and Tuesday will feature much cooler weather with highs only in the low to mid 70's with night well down into the 50's with 40's possible in our usually colder valley locations. We briefly warm again toward Thursday before we turn cooler for next weekend.

[Voyager]

Despite a few camera malfunctions, I got some video of the Union Pacific Big Boy in Nesquehoning this morning. When I get them edited and uploaded to YouTube, I'll share them here.

[TheDreamTraveler]

4 hours ago, Yardstickgozinya said:

Thursday is looking particularly interesting and it's truly worth keeping an eye on. Keyword elevated mixed layer. That's the main dynamic  that  keeps us safe out here east of the mighty mississipp and why we almost never see the big outbreaks the central and western united states sees. If it truly surges out ahead, this  absolutely could be one for the record books. Contrary to popular belief It's not the mountains, the ocean breeze or lack of unmodified gulf air, thst prevents Central and Western type outbreaks from occurring this far east .  EML lag is the true culprit.  if we have the EML we're capable of achieving  Central and Western United States type indices ,including those gargantuan fat capes in excess of 4000jkg that the MA/NE only see every thirty to forty years. 

I do always wonder when PA will see another outbreak like the May 1989 tornado outbreak. It's always a matter of when not if but it sure has been a long time since that's happened. I'm always in the camp of 'nothing ever happens' since that's usually how it is but eventually we'll get a day where that's not the case.

[Yardstickgozinya]

1 hour ago, TheDreamTraveler said:

I do always wonder when PA will see another outbreak like the May 1989 tornado outbreak. It's always a matter of when not if but it sure has been a long time since that's happened. I'm always in the camp of 'nothing ever happens' since that's usually how it is but eventually we'll get a day where that's not the case.

I'm not familiar with that outbreak. However, it was a major player in the  5/31/85 outbreak for western pennsylvania. 

An additional component to the magnitude of the thunderstorms on May 31^st was the presence of a significant “elevated mixed layer” (EML) , a common supporting ingredient in severe weather across the northeastern U.S. (Banacos and Ekster).  EMLs act as a ‘lid’ in the atmosphere, stopping convection from occurring unless the lid can be removed or sufficient lift is present. The strength of the front and the degree of instability lead to the erosion or breaking of the cap and thunderstorms exploded with violent results.

This following two figures from Markowski show 1, the presence of the EML in the 7pm May 31^st Pittsburgh sounding and 2, the formation and subsequent migration of the EML across the United States.

The following hand-analyzed upper air maps (provided by NWS Cleveland) from the morning of the 31st highlight the significant area of dry air (yellow shading) or ‘cap’ coming into play. The forecaster even analyzed a dryline (the bumpy blue line through the central Plains) on the 850mb map, showing the leading edge of the dry air.