Central PA Spring 2026 Discussion/Obs Thread

[MAG5035]

On 3/16/2026 at 4:43 PM, canderson said:

Has the lack of vertical instability on the storms been what caused nothing to bring down the shear winds? We had not much cape but that’s not a need when interacting with shear levels so curious why everything has been muted so much. 

I was looking back at the SPC mesoanalysis from yesterday and parameters were really not all that impressive outside of the shear and low level winds. I just don’t think we had sufficient enough mixing out of the boundary layer or daytime heating (lots of cloud cover) to really tap into much potential. DCAPE’s were only on the order of a few hundred j/kg. Standard CAPE’s were only about 500 or so at best down south where there were still a decent amount of severe wind reports. But I noticed from the SPC map ITT shared up above that they were all of the standard severe wind variety, with 0 tornado or 75mph or greater reports.

Short range meso models were hinting at these limitations some which was why I was reserved on the severe potential a bit. I was still concerned some, I was figuring on a couple spin ups so I’m surprised there weren’t any reports at all. But would I have claimed essentially the weather rapture if I had 243k followers? Probably not haha. If we would have had the air mass we had last week when we were basking in the upper 70s- upper 80s in the Mid-Atlantic this absolutely would have been a much more significant event. 

At any rate, more locally mesoanalysis had a persistent area of CIN in the Lower Sus Valley. Low level stability is going to cap transferring the really high winds to the surface. The radars not very detailed on these maps but that was the cluster that popped a couple tornado warnings in MD before it moved into southern PA. 

This map is showing mixed layer CAPE (red), CIN (blue dashed), and effective bulk shear (wind barb).

 

[Mount Joy Snowman]

Actual low here last night was 28 and some residual snow and ice melt brings my total tally to 1.7”, which I believe puts me amongst the highest totals in the state for yesterday. Neat. 

[Yardstickgozinya]

   The reasons why I don't post velocitie signatures is because deciphering velocities in rotating cells is often not nearly as straightforward as a lot of peoples thinking. You have to really know what you're doing, or it's very easy to make big mistakes reading srorm velocitie signatures. 

 

 

[mahantango#1]

1 hour ago, Voyager said:

Whatever ripped on the Blue Mountain out my way was nasty. 309 was closed for 14 hours for cleanup. My night shift partner hit it and thought it was going to flip the truck.

Didn't I read 309 is still closed at 3:45pm?

[Voyager]

40 minutes ago, mahantango#1 said:

Didn't I read 309 is still closed at 3:45pm?

Yup. They opened it up sometime around 5pm.

[mahantango#1]

3 minutes ago, Voyager said:

Yup. They opened it up sometime around 5pm.

Did NWS get called to investigate the damage?

[Jns2183]

Here is a PDF of every tornado, severe storm, flood warning CTP issued May 25-28, 2011. To say they were busy with being understatement it's 345 pages. Page 136 and I think page 305 give or take five pages is where some good stuff is. I'm hosted on my Google drive so here's a link.

https://drive.google.com/file/d/1rZ-v0WQLuBEK60otdrIPOwoibLsrBwgf/view?usp=drivesdk

It was made by IEM raccoon
https://mesonet.agron.iastate.edu/raccoon/?wfo=CTP&radar=CCX&product=N0Q&wtype%5B%5D=FF&wtype%5B%5D=SQ&wtype%5B%5D=SV&wtype%5B%5D=TO&year=2011&month1=5&day1=10&hour1=0&month2=3&day2=27&hour2=23

Outside is the greatest thing ever in existence for weather data. Australia spent 20 hours exploring it and I'm just now starting to understand everything it can do it truly is the best thing out there by far.

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[Jns2183]

I was looking back at the SPC mesoanalysis from yesterday and parameters were really not all that impressive outside of the shear and low level winds. I just don’t think we had sufficient enough mixing out of the boundary layer or daytime heating (lots of cloud cover) to really tap into much potential. DCAPE’s were only on the order of a few hundred j/kg. Standard CAPE’s were only about 500 or so at best down south where there were still a decent amount of severe wind reports. But I noticed from the SPC map ITT shared up above that they were all of the standard severe wind variety, with 0 tornado or 75mph or greater reports.
Short range meso models were hinting at these limitations some which was why I was reserved on the severe potential a bit. I was still concerned some, I was figuring on a couple spin ups so I’m surprised there weren’t any reports at all. But would I have claimed essentially the weather rapture if I had 243k followers? Probably not haha. If we would have had the air mass we had last week when we were basking in the upper 70s- upper 80s in the Mid-Atlantic this absolutely would have been a much more significant event. 
At any rate, more locally mesoanalysis had a persistent area of CIN in the Lower Sus Valley. Low level stability is going to cap transferring the really high winds to the surface. The radars not very detailed on these maps but that was the cluster that popped a couple tornado warnings in MD before it moved into southern PA. 
This map is showing mixed layer CAPE (red), CIN (blue dashed), and effective bulk shear (wind barb).

 

Looks like CAD almost with the position of the CIN

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[Jns2183]

   The reasons why I don't post velocitie signatures is because deciphering velocities in rotating cells is often not nearly as straightforward as a lot of peoples thinking. You have to really know what you're doing, or it's very easy to make big mistakes reading srorm velocitie signatures. 
 
 

Unless someone has a mobile Doppler radar in the backyard any velocity signature around here he's going to be up in the mid levels around 5,000 to 6,000 ft just due to the the tilt of the radar

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[canderson]

9 minutes ago, Jns2183 said:

Unless someone has a mobile Doppler radar in the backyard any velocity signature around here he's going to be up in the mid levels around 5,000 to 6,000 ft just due to the the tilt of the radar

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I should buy one. Does Costco carry them? 

[Voyager]

34 minutes ago, mahantango#1 said:

Did NWS get called to investigate the damage?

I haven't heard anything yet. I went up the mountain after my last load when it finally opened, and you couldn't tell that anything even happened. 

[Itstrainingtime]

Temp here is already down to 27. AC is currently silent but on standby for the weekend. No heat until next November or December.

[Mount Joy Snowman]

6 minutes ago, Itstrainingtime said:

Temp here is already down to 27. AC is currently silent but on standby for the weekend. No heat until next November or December.

You are a damn polar bear! A nice little snow shower just rolled through here that dropped the temp to 28, got the treetops moving, and had some heavy flurry action. Fun. 

[Voyager]

So I look outside and find out that a squall went through and dropped 3/4 inch....