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April 24-28 Severe/Warmth Thread


NaoPos

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not trying to be negative, but I wonder what's keeping these storms from getting stronger? We're plenty unstable, but especially the northern ones seem to keep falling apart.

I wish you'd take me off ignore, and basic Meteorology even pro's will say it that the atmosphere was robbed of energy from the storms earlier and now we have cloud cover which goes against the storms growing at least down here. I am not joking or making this up that even Mets have said that sometimes the atmosphere can be robbed of energy if a cell is stronger then the ones trying to form or that the cell that is stronger may absorb the ones trying to form. ask any met.

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The storm near Chestertown will be warned any minute now. Supposedly 1" hail in there. And the one behind it in MD looks nice as well. Too bad they're moving E, not NE.

I wonder why we can get storms to regenerate over the same area, but can't get new ones to form where the atmosphere should still be unstable.

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not trying to be negative, but I wonder what's keeping these storms from getting stronger? We're plenty unstable, but especially the northern ones seem to keep falling apart.

Too dry in the low-levels, high LCL, low wind speed shear in the lower levels, poor mid-level lapse rates... take your pick.

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Too dry in the low-levels, high LCL, low wind speed shear in the lower levels, poor mid-level lapse rates... take your pick.

Yea. LAck of forcing was the main culprit.

Lee, the energy wasn't robber. But when you have a mcs that rolled through the dc-Balt region earlier, it does 2 things. Cools the north side ( our region) atthe mid levels and stabilizes for a period of time, ( morning mcs Arent as restrictive if you can clear skies the rest of the day.) and 2, creates an outflow boundary on the south side. That's what the cells in Md are doing now, following alongside that boundary.

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Too dry in the low-levels, high LCL, low wind speed shear in the lower levels, poor mid-level lapse rates... take your pick.

Ok fine then. Make me look stupid. See if I care. :arrowhead:

Seriosuly though, what LCLs are good for us? I know for western storms if the LCL is too low you get mucky low-base HP messes, but around here we'll take anything. Is it just a case of the lower the better?

Also, I thought mid-level lapse rates around 6 were okay. Not great, but okay, no?

Anyway I seriously do appreciate your advice in all this.

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Ok fine then. Make me look stupid. See if I care. :arrowhead:

Seriosuly though, what LCLs are good for us? I know for western storms if the LCL is too low you get mucky low-base HP messes, but around here we'll take anything. Is it just a case of the lower the better?

Also, I thought mid-level lapse rates around 6 were okay. Not great, but okay, no?

Anyway I seriously do appreciate your advice in all this.

I'm not ellinwood but ill say this. Ideally, you wanna see mid level lapse rates between 7-7.5 degrees for severe weather.

Can a mod change the threat title to mid week warmth, daily thunderstorm chances?

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Yea. LAck of forcing was the main culprit.

Lee, the energy wasn't robber. But when you have a mcs that rolled through the dc-Balt region earlier, it does 2 things. Cools the north side ( our region) atthe mid levels and stabilizes for a period of time, ( morning mcs Arent as restrictive if you can clear skies the rest of the day.) and 2, creates an outflow boundary on the south side. That's what the cells in Md are doing now, following alongside that boundary.

I wouldn't think lack of forcing was the MAIN culprit, but there was definitely a lack of good synoptic forcing present.

Ok fine then. Make me look stupid. See if I care. :arrowhead:

Seriosuly though, what LCLs are good for us? I know for western storms if the LCL is too low you get mucky low-base HP messes, but around here we'll take anything. Is it just a case of the lower the better?

Also, I thought mid-level lapse rates around 6 were okay. Not great, but okay, no?

Anyway I seriously do appreciate your advice in all this.

With LCLs, it's generally the lower the better. Stronger forcing can help alleviate some of the inhibition that higher LCLs create. If the lapse rates are less than 6.5 K/km (which is the moist adiabatic lapse rate), than you have a stable atmosphere. You want it to be >6.5 to have an unstable atmosphere (which is when you start to get CAPE).

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I'm not ellinwood but ill say this. Ideally, you wanna see mid level lapse rates between 7-7.5 degrees for severe weather.

Can a mod change the threat title to mid week warmth, daily thunderstorm chances?

Just edit your first post in this thread and you can change that info.

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I wouldn't think lack of forcing was the MAIN culprit, but there was definitely a lack of good synoptic forcing present.

With LCLs, it's generally the lower the better. Stronger forcing can help alleviate some of the inhibition that higher LCLs create. If the lapse rates are less than 6.5 K/km (which is the moist adiabatic lapse rate), than you have a stable atmosphere. You want it to be >6.5 to have an unstable atmosphere (which is when you start to get CAPE).

Ah I see. Thanks. So there's no such thing as a too-low LCL?

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I had about three or four good rumbles of thunder maybe 30-40 minutes ago.

And 0.13" of rain from the PM showers/storms.

Unfortunately tomorrow's threat looks like it's too late. The 18z NAM has a decent-looking line on sim radar moving through Central PA around 3z but it falls apart after that.

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0z NAM looks rather unimpressive for Wed. CAPE is at a minimum, bulk shear is almost nonexistent, and low-level helicity is around 125, which is also not supportive of a tornado threat.

The 18z GFS has moderate instability (~750 to 1000 J/Kg) and better bulk shear.

I haven't really looked into the synoptic differences yet, but it appears there is a major difference in there somewhere. SREF Sig Tornado Progs have been pretty accurate for Midwest events recently, so my curiosity is certainly peaked.

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I had about three or four good rumbles of thunder maybe 30-40 minutes ago.

And 0.13" of rain from the PM showers/storms.

Unfortunately tomorrow's threat looks like it's too late. The 18z NAM has a decent-looking line on sim radar moving through Central PA around 3z but it falls apart after that.

I'm with you there. Salem and Cumberland counties in NJ are still getting it pretty good but I'm too far north to see any of it here. Seems to be a recurring theme this year. All places down in delaware, Maryland and Cape May counties get it the worst and we end up just missing it. Tomorrow looks like the LV and poconos may see a little action as the frontal boundry stalls to the north. Just going to be hot and humid here. :l

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0z NAM looks rather unimpressive for Wed. CAPE is at a minimum, bulk shear is almost nonexistent, and low-level helicity is around 125, which is also not supportive of a tornado threat.

The 18z GFS has moderate instability (~750 to 1000 J/Kg) and better bulk shear.

I haven't really looked into the synoptic differences yet, but it appears there is a major difference in there somewhere. SREF Sig Tornado Progs have been pretty accurate for Midwest events recently, so my curiosity is certainly peaked.

Yup, that's what caught my eye, the SREF has been dead on with outbreaks in the midwest and such so far this year.

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Yup, that's what caught my eye, the SREF has been dead on with outbreaks in the midwest and such so far this year.

I wouldn't say dead on. There was an outbreak in central IL a few weeks back that busted, and the Wisconsin supposed-to-be-a-High-Risk-Day event also didn't turn out so well. But otherwise yeah, it's been rather accurate.

Where do you get those maps? I had it bookmarked at one point...

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Yea. LAck of forcing was the main culprit.

Lee, the energy wasn't robber. But when you have a mcs that rolled through the dc-Balt region earlier, it does 2 things. Cools the north side ( our region) atthe mid levels and stabilizes for a period of time, ( morning mcs Arent as restrictive if you can clear skies the rest of the day.) and 2, creates an outflow boundary on the south side. That's what the cells in Md are doing now, following alongside that boundary.

Yesterday wasn't expected to be a widespread severe or even a widespread thunderstorm event...a slight risk doesn't mean certainty -- the odds were 15 in wind and hail. The AFD's from Mount Holly alluded to a litany of reasons against widespread severe...and the forecast verified pretty well (radar hi res from the SPC was awful on the southern storms).

When you get thunderstorms firing in a scattered nature, some get screwed and others get the "benefit" of the storms popping.

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06z NAM has increased instability for Wed. (generally 1000 to 1500 J/Kg) but there's still no low-level or mid-level helicity or any bulk shear that seems to support the SREF's Sign Tornado progs (which on the 3z run were a 10 across all of E PA and a 20 across NE PA)

Sim radar also has nothing this far south.

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