New England Severe weather thread number ...I think XI ?

[CoastalWx]

Yeah, I'm not one to talk.

It's been a while since I've been in a true SVR storm. I guess the nightime nickels I had back In early June 2010 were the closest. It dropped ping pongs down the street at amarshall's area.

[free_man]

It's been a while since I've been in a true SVR storm. I guess the nightime nickels I had back In early June 2010 were the closest. It dropped ping pongs down the street at amarshall's area.

That supercell was ridiculous. The 100mph or whatever winds in NYS around 1am were indicative of how nasty that was.

[CoastalWx]

Well it looks like the south coast did get some rain, while the split worked for my area. Just a few hundredths to show. No thanks to the high dews. The MA can keep them.

[CoastalWx]

Friday and/or Saturday could be interesting, with embedded cells.

[Damage In Tolland]

Thurs-Sat looks like 3 days of more wild storms

[amarshall]

It's been a while since I've been in a true SVR storm. I guess the nightime nickels I had back In early June 2010 were the closest. It dropped ping pongs down the street at amarshall's area.

I have the pictures somewhere.... and not a single skylight was saved that day. I had my first legitimate dents in my hood from hail.

My uncle was bringing his 67 Shelby GT350 mustang down for the 4th of July from Burlington. He decided to wait it out. It would have destroyed a very expensive paint job on a hotrod.

I just found this on youtube

[youube]

[CoastalWx]

I have the pictures somewhere.... and not a single skylight was saved that day. I had my first legitimate dents in my hood from hail.

My uncle was bringing his 67 Shelby GT350 mustang down for the 4th of July from Burlington. He decided to wait it out. It would have destroyed a very expensive paint job on a hotrod.

I just found this on youtube

[youube]

Yeah my folks had hail in that, but a few miles away in Scituate had baseballs.

[HM]

Anyone noticing the broken record here?

So last week I mentioned the potential for the end of this week for severe and now this week I am going to mention the potential at the end of next week.

The SPC has already mentioned the Mid Atlantic Friday, especially with the GFS solution trending toward the ECMWF. As WIZ would say, this is looking like a Mid Atlantic potential if we were going to see tornadoes, given the autumn-like set up aloft.

Next week, the data retrogrades the trough, possibly setting up an EML advection scenario or a close call later next week. It will most likely not be a true advection; however, the pattern is so hot and dry that perhaps even a "bootleg" pattern would even allow for a true EML advection.

[CoastalWx]

Anyone noticing the broken record here?

So last week I mentioned the potential for the end of this week for severe and now this week I am going to mention the potential at the end of next week.

The SPC has already mentioned the Mid Atlantic Friday, especially with the GFS solution trending toward the ECMWF. As WIZ would say, this is looking like a Mid Atlantic potential if we were going to see tornadoes, given the autumn-like set up aloft.

Next week, the data retrogrades the trough, possibly setting up an EML advection scenario or a close call later next week. It will most likely not be a true advection; however, the pattern is so hot and dry that perhaps even a "bootleg" pattern would even allow for a true EML advection.

Friday or Saturday do look interesting around the northeast..maybe even into SNE.

[radarman]

Yesterday was impressive around here, but it makes you realize just how strong severe criteria winds are, and that most likely the vast number of SVRs are technically false alarms.

I measured a swath of 53kt winds sweeping through corn fields just south of Rt. 9 in Hadley yesterday, as low as 700' AGL. It's really quite unusual, and yet it probably doesn't quite reach the 50kt threshold for severe at the ground. The 62kt velocity in Feeding Hills was 6500' AGL. Both of these are capable of planting a tree on top of your car, and in that respect deserve warnings of some kind, but it goes to show that a true SVR is nothing to mess around with.

[radarman]

Most impressive of the day was a brief isolated microburst between 91 and Rt. 5 near the Ct. River Oxbow on the Easthampton/Northampton line. 64 kts at 2400' AGL.

[Flying MXZ]

Wow...a pilot as well as 3 other people reported a tornado at Sidney Airport in NY at 6:04 PM

http://www.wbng.com/results?search=site&keywords=sidney+tornado&searchbutton=Go

http://binghamton.ynn.com/content/top_stories/594230/national-weather-service-investigating-possible-tornado-in-sidney/

[OceanStWx]

http://www.wbng.com/...searchbutton=Go

http://binghamton.yn...nado-in-sidney/

Despite the shaky video, you can easily see the rotation in the clouds as well as what looks like dust/debris being lofted near the ground.

Quite a stark difference from that "funnel" reported a week or so ago on the North Shore.

[radarman]

One more from the most supercell-like structure of the day yesterday. This was from the second round of storms... perhaps after the LLJ picked up a tad. The echo in the notch actually is a borderline spinup micro-vortex. Just 1-2 frames before it's a very weak echo with hints of g2g shear that quickly blossoms. They are very hard to diagnose because of the low signal. The literature tells us that most of these last less than a minute and are only 50-100 M wide... often within a single Nexrad gate. This occurred deep in the forest, and perhaps "didn't make a noise". It's only if these hit someone's shed can we really ever say for sure if it's real or a radar hallucination.

[HM]

Friday or Saturday do look interesting around the northeast..maybe even into SNE.

Let's keep in mind the last several upper lows / deeping SLPs that were modeled to slice through the NE coastal plain only to trend slower / further NW. For now, we should closely watch trends in these main players. A situation like this can easily turn into a warm front issue / severe threat shifting well SW of us. The one good Mid Atlantic tornado outbreak back in June had a similar appearance aloft if I'm not mistaken but take that with a grain.

Yesterday was impressive around here, but it makes you realize just how strong severe criteria winds are, and that most likely the vast number of SVRs are technically false alarms.

I measured a swath of 53kt winds sweeping through corn fields just south of Rt. 9 in Hadley yesterday, as low as 700' AGL. It's really quite unusual, and yet it probably doesn't quite reach the 50kt threshold for severe at the ground. The 62kt velocity in Feeding Hills was 6500' AGL. Both of these are capable of planting a tree on top of your car, and in that respect deserve warnings of some kind, but it goes to show that a true SVR is nothing to mess around with.

One of the reasons I was a bit more adamant than usual about severe weather was the exceedingly moist air mass and h2 ridge overhead, supplying some overturning. The idea of a convective system wasn't a bad one as we did develop around 3 clusters of organized thunderstorms. Also, a good sufficient LLJ on the outskirts of the best MLJ can actually aid in this overturning that the h2 ridge will allow, keeping the warm sector available to tap.

[Ian]

The one good Mid Atlantic tornado outbreak back in June had a similar appearance aloft if I'm not mistaken but take that with a grain.

500 setup with strong vort/trough over lower lakes is usually one to consider tornadoes in this area off of.. I'd prob rather not have a closed low but it worked on June 1.

[OceanStWx]

Despite the shaky video, you can easily see the rotation in the clouds as well as what looks like dust/debris being lofted near the ground.

Quite a stark difference from that "funnel" reported a week or so ago on the North Shore.

As I surmised after seeing that video, here is the volume scan associated with the tornado touch down.

Reflectivity looked much more supercellular prior to this time, but you can still see the structure here. SRM was broad and around 50 to 60 kts on the meso. Move onto dual-pol variables (ZDR bottom left, CC bottom right) and you can clearly see an area of near 0 ZDR and very low CC (tornadic debris signature). This all at about 2 kft AGL.

Now this is all well and good, but it would not have increased lead time any. At best BGM may have been able to put out a zero lead time TOR. This is because the debris signature appears AFTER the tornado touches down. Also keep in mind that it will continue to be there even after the tornado may have lifted, because debris is still in the air.

BGM in my mind did correctly use dual-pol data to time stamp the LSR at 604 PM and mark the location of occurrence at 2 S of Sidney (roughly where the red marker is on the image).

[HM]

500 setup with strong vort/trough over lower lakes is usually one to consider tornadoes in this area off of.. I'd prob rather not have a closed low but it worked on June 1.

I know what you mean about closed lows. With a closed low, the wind fields can become disjointed as s/w in the flow begin to deepen out heights, locally, further downstream and raise them behind them. Also, the SLP usually isn't intensifying anymore as it becomes vertically stacked, possibly reducing the amount of backing flow across the Mid Atlantic.

[HM]

Now this is all well and good, but it would not have increased lead time any. At best BGM may have been able to put out a zero lead time TOR. This is because the debris signature appears AFTER the tornado touches down.

I don't mean to be a dbag, but when would a debris signature appear before a tornado touches down?

[Ian]

I know what you mean about closed lows. With a closed low, the wind fields can become disjointed as s/w in the flow begin to deepen out heights, locally, further downstream and raise them behind them. Also, the SLP usually isn't intensifying anymore as it becomes vertically stacked, possibly reducing the amount of backing flow across the Mid Atlantic.

Yep. I kinda poo-pooed the potential on June 1 because it was a strong closed low but it didn't seem to matter much other than perhaps nothing being very strong or long lived. Plenty of time for shifts. I think troughs have ended up further north than modeled in this range but we'll see. Not your typical August pattern...

[CT Rain]

I know what you mean about closed lows. With a closed low, the wind fields can become disjointed as s/w in the flow begin to deepen out heights, locally, further downstream and raise them behind them. Also, the SLP usually isn't intensifying anymore as it becomes vertically stacked, possibly reducing the amount of backing flow across the Mid Atlantic.

At least the low is closing off and still deepening relatively far east. A closed low that's ejecting east and opening up is always a disappointment. We will have to watch this situation even in SNE. 75+ SSTs is a plus this time of year compared to a spring ULL situation.

[CT Rain]

Yep. I kinda poo-pooed the potential on June 1 because it was a strong closed low but it didn't seem to matter much other than perhaps nothing being very strong or long lived. Plenty of time for shifts. I think troughs have ended up further north than modeled in this range but we'll see. Not your typical August pattern...

Farther north would be good up here. Maybe I'll chase on Friday lol.

[HM]

Yep. I kinda poo-pooed the potential on June 1 because it was a strong closed low but it didn't seem to matter much other than perhaps nothing being very strong or long lived. Plenty of time for shifts. I think troughs have ended up further north than modeled in this range but we'll see. Not your typical August pattern...

I agree that things may end up further n/w with time but it certainly is an unusual trough for August. Maybe some of the New England guys can chime in about 6/1 because I remember us being adamant about tornadoes (especially Paul) for the Mid Atlantic in the medium range, despite the upper low concerns.

[radarman]

Now this is all well and good, but it would not have increased lead time any. At best BGM may have been able to put out a zero lead time TOR. This is because the debris signature appears AFTER the tornado touches down.

I don't mean to be a dbag, but when would a debris signature appear before a tornado touches down?

Yeah CC drops are more useful from the emergency response perspective than the forecasting perspective. Adds confidence to the situation and gives clues about potential severity.

Given the highly varied ability of Emergency Managers to interpret radar data (and WFO products for that matter) I wonder if we'll see an increasing role of professional forecasters issuing specific instructions to first-responders. Trying to do this via EMs can be difficult given the fast evolution of systems and delays associated with communicating through multiple layers.

[HM]

At least the low is closing off and still deepening relatively far east. A closed low that's ejecting east and opening up is always a disappointment. We will have to watch this situation even in SNE. 75+ SSTs is a plus this time of year compared to a spring ULL situation.

Good points. But, a closed low is a closed low and surprisingly our models still aren't the best with the maturing-vertically stacking process (which may make all the difference). I agree about the SST and why backing winds may not be a bad thing; however, I would be worried about warm sector junk with this setup.

[Ian]

I agree that things may end up further n/w with time but it certainly is an unusual trough for August. Maybe some of the New England guys can chime in about 6/1 because I remember us being adamant about tornadoes (especially Paul) for the Mid Atlantic in the medium range, despite the upper low concerns.

A good majority of MA tornado events have a trough in that general area... I recognized that early for June 1 but combo of being out of town and not liking to forecast potential prob hurt my verification. It's certainly worth watching IMO.

[CT Rain]

Good points. But, a closed low is a closed low and surprisingly our models still aren't the best with the maturing-vertically stacking process (which may make all the difference). I agree about the SST and why backing winds may not be a bad thing; however, I would be worried about warm sector junk with this setup.

Of course. I'd rather see a strong sw not closed off but still something to watch given the time of year.

[OceanStWx]

I don't mean to be a dbag, but when would a debris signature appear before a tornado touches down?

I stressed the after because it seems to be a pretty common misconception that TDSs will somehow help increase TOR lead times.

Edit: Misconception at least among some of the non-professional articles I've read talking about how how dual-pol will improve forecasting.

[HM]

A good majority of MA tornado events have a trough in that general area... I recognized that early for June 1 but combo of being out of town and not liking to forecast potential prob hurt my verification. It's certainly worth watching IMO.

Well even if you are away chasing in tornado alley, we still welcome your thoughts for the Mid Atlantic.

[HM]

I stressed the after because it seems to be a pretty common misconception that TDSs will somehow help increase TOR lead times.

Edit: Misconception at least among some of the non-professional articles I've read talking about how how dual-pol will improve forecasting.

Gotcha. It is always startling that misconceptions like these even start up at all.