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Severe Weather Threat Friday?


weatherwiz

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Upton has one between 750 and 650mb and another between 600mb and 500mb. The temperature profile is nearly parallel to the dry adiabat in those layers. The dry adiabats are the green lines that run from the right bottom to the top left.

Elevated mixed layers are correlated with significant/major severe weather outbreaks in the NE. They enhance updraft potential through steep lapse rates and greater instability and increase downdraft potential due to the very dry air. This air has likely advected relatively uncontaminated from the high deserts of the SW US and northern MX. That layer can also serve as a cap to keep convection at bay until it breaks through lift in the mid to late afternoon causing more explosive convection initiation.

I have grasped the cap portion of an EML but not the actual appearence on the skew.. okay parrarel to the green lines which is the dry adiabats.. but on a sample skew I saw online someones pointed at the EML being a layer near 500 where the dp is almost equal to parcel temperature. I either misread that or they were wrong. That would contradict what you are saying about the very dry air...

What maximizes a mixing layer closer to the surface? What allows it to occur? I know momentum trnfr on the bufkit is a way to see what height it mixes to and the wind gust potential.

To me in my amateur eye good mixing seems to occur when the parcel temp follows the dry adibatics as far up in the atmosphere as possible.. if there was no difference in temp or a constant drop in temp right to the top of the atmosphere would there be unlimited mixing potential? Warm air over cold air seems like the basic description of mixing death to me

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I have grasped the cap portion of an EML but not the actual appearence on the skew.. okay parrarel to the green lines which is the dry adiabats.. but on a sample skew I saw online someones pointed at the EML being a layer near 500 where the dp is almost equal to parcel temperature. I either misread that or they were wrong. That would contradict what you are saying about the very dry air...

What maximizes a mixing layer closer to the surface? What allows it to occur? I know momentum trnfr on the bufkit is a way to see what height it mixes to and the wind gust potential.

To me in my amateur eye good mixing seems to occur when the parcel temp follows the dry adibatics as far up in the atmosphere as possible.. if there was no difference in temp or a constant drop in temp right to the top of the atmosphere would there be unlimited mixing potential? Warm air over cold air seems like the basic description of mixing death to me

that doesn't make a lot of sense. It's typically very dry at the base of the EML and then the RH increases with height.

Mixing near the surface is maximized when it is sunny, it's not humid, and it's windy. This allows the mixed layer to be the deepest. Sometimes in the desert you can see the surface mixed layer over 300mb deep. Around here it can occasionally be 200mb deep (800mb)..but is usually more like 100 or 150mb deep (850 or 900mb)

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Maybe I should head to the Albany area tomorrow? Could be a great spot as they will be better to the best UL forcing and will still be at least moderately unstable, ML lapse rates may not be as steep as just further east but shear aloft may be a bit more maximized causing longer and more curved hodo's.

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Tomorrow will be real interesting...not sure what to expect for much of SNE (except for perhaps western MA/CT) but damaging winds and large hail should again be major threats...could be an isolated tornado threat, however, like today LCL's are going to be fairly high which may mitigate this potential.

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Going to have to watch to see if the NAM is indeed overdoing the dewpoints, so far given the current state of the dewpoints the GFS has the better handle. Looking upstream (or downstream...always confused on how you use these terms) there really isn't any dewpoints near 70F that would advect up this way. If this is the case instability numbers will not be as high as Thursday.

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Not only do we have to see the dewpoint situation but also with how strong the shear is aloft. The NAM does weaken 700mb winds by the afternoon, however, the GFS and the latest SREF actually keep 700mb winds anywhere from 30-50 knots compared to the 325-35 knots on the NAM...this is a substantial difference.

Currently at 700mb there is about 35-45 knots of wind...both the NAM/GFS had this for around 9z so I guess we'll just have to watch and see what occurs.

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Just texted mike.. hes probably knocked out

I got that text this monring, Jay--thanks.

Was the cell lmoving NE? It must have passed to my south and moved NE from there. Close enough where I was getting some decent winds and caught enough rain to leave the driveway wet this morning. But the lightning--which was impressive enough to wake me--and thunder were off to my east. Here's hoping for a direct hit today!

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Couldn't sleep, nothing to do with the excitement, I just couldn't sleep. Going to really suck, I'm pretty exhausted, been all week. Oh well, maybe I'll try a 5-HR energy for the first time.

I'd shoot for ALB around noon. And then you can go from there. It's an easy drive from HFD to ALB.

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I still think the best severe threat is going to be north of ALB and into VT later today.

Maybe GFL and RUT?

That's awful chasing area up there but that is probably will be the best threat.

We were thinking of leaving here around 9:30 AM...I just got directions to a public library there, just over 2 HR's away...I was actually thinking Rutland area as well...good spot for maximized shear...instability won't be the highest but still plenty high.

Not all too far from Albany either...we can always go north if needed as well.

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You think they get hit again? From GFL north got hit pretty hard last night.

Depends how well the atmosphere recovers and how unstable areas north of ALB get. They have the best wind shear and synoptic scale left (right entrance region of jet streak).

The best instability though... with steepest mid level lapse rates... will be south of ALB toward POU, the Berkshires, and W CT.

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We were thinking of leaving here around 9:30 AM...I just got directions to a public library there, just over 2 HR's away...I was actually thinking Rutland area as well...good spot for maximized shear...instability won't be the highest but still plenty high.

Not all too far from Albany either...we can always go north if needed as well.

I would stay in ALB until the threat becomes more clear. It could wind up south of there... if strong instability fails to develop near RUT/GFL. Best mid and low level shear will stay NE of ALB but I'm not sure how unstable they'll get.

Great Barrington is another option for you. You can scoot west toward ALB/Columbia/Rensselaer County if you have to. Or shoot straight north of Rt 7 into Berkshire County.

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