Tuesday/Wednesday Storm

[radarman]

Maybe I'm a bit ignorant to "verifying" a watch because I thought it would be handled like a convective outlook. If it is something probabilistic then how can it have a simple FAR? Even if nothing happens, is it fair to judge a watch in this manner?

Calculating FAR is almost never simple around here, even if you're talking about warnings instead of watches. Verification is subject to ground truth, which is generally hard to come by when the vast majority of things go unsurveyed, and terrain makes spotting difficult. Also, tornado warnings are often phrased as, "a thunderstorm capable of producing a tornado", not necessarily, "a tornado is on the ground". If it doesn't produce a tornado, does that mean it wasn't capable of producing a tornado? With respect to watches, I think most would agree that the June 2010 watch was a bust when calling a 90% chance of 2 or more tornadoes, but technically it wasn't when they allowed 10% chance of 1 or zero tornadoes. The only metric that really matters in the end is general public confidence and even that is widely skewed by perception or misperception.

Although people like quantitative metrics for evaluating forecasts and forecasters they can be extremely hard to come by. I deal with this a lot when trying to evaluate automated detection algorithms, or doppler wind field models... Was it right? Was it wrong? At some point you just have to shrug your shoulders and move on.

[ORH_wxman]

Surprising. CEF had a gust to 40 though CT Rain pointed out that the valley can do well on southerlies it's not often wind speeds here will exceed those sites with much greater elevation.

I also think areas to the west and southwest had the advantage of a slightly less stable BL during the time of max LLJ than further east...despite BOS/PVD getting solid gusts. This had been mentioned yesterday.

But certainly the terrain effects on southerly wind events if going to be different than a NW pressure rise high wind event. The CT Valley does funnel the wind effectively on a south flow as the valley narrows when you head north...the opposite effect versus other wind directions with a northerly component.

[HM]

I say it is fair.

For starters public perception (i.e. the end user) is huge. The public hears TORNADO watch (Part of i is based on the fact that most of the genral public doesn't know the difference of watch vs. warning). Past two strong cold fropas were wind events and verified as such; yes there was a tornado threat in both cases but the tornado threat was much lower than the WIND threat was. How many tornadoes occured yesterday in the TW across the NEUS and New England? Same on Sept 8th (for the watch areas north of the SENY/SW CT one).

From Doswell, et al Tornado Forecasting: A Review -

"Another important aspect of tornado forecast verification is that tornado watches are area forecasts that typically cover several tens of thousands of square kilometers, whereas tornadoes affect only a few square kilometers even in major events. This disparity in coverage means that successful tornado watches (i.e., those with tornadoes in them) are mostly "false alarms" in the sense that the vast majority of the forecast area is unaffected. The original watch verification schemes considered them as area forecasts, so that a single tornado effectively verified the entire area of the watch. Recently, as described in Weiss et al. (1980), watch verification has been changed such that a single report only verifies a portion of the total watch area/time. However, this new scheme still does not incorporate information about areas outside the watch."

Yes I see what you're saying and agree that watch verification is a tricky area.

1. A portion of the public doesn't understand watch vs. warning and I agree that communication remains an issue. I think there is a level of sensitivity to this high-impact region with plenty of events going on (e.g. sports, music) usually and a lot of people.

2. What happened in the past is not exactly a point in the sense you used it in your post. There is something to pattern recognition and what a particular season tends to do, but the circumstances between yesterday's event and anything prior were much different...even if results were similar or worse.

3. Usually, wind probabilities are highest in this area and tornado probabilities that exceed wind don't occur in this part of the US.

Do I think the decisions yesterday were warranted? Not exactly...

Do I think it did them a disservice? No...

[CT Rain]

So what happened last night in E CT... widespread tree damage from Lebanon to Hampton.

There was a remnant bow structure with a few embedded low level mesocyclones. My guess is that one of those low level mesos helped the downward transport of some of the LLJ.

While the squall line produced only very minor/isolated damage in most of the state there was a swath from SW to NE in east central CT that got raked pretty good last night.

[CoastalWx]

So what happened last night in E CT... widespread tree damage from Lebanon to Hampton.

There was a remnant bow structure with a few embedded low level mesocyclones. My guess is that one of those low level mesos helped the downward transport of some of the LLJ.

While the squall line produced only very minor/isolated damage in most of the state there was a swath from SW to NE in east central CT that got raked pretty good last night.

Was that the cell we talked about late last night?

[CT Rain]

Was that the cell we talked about late last night?

Yes but prior to it taking on that infamous no-hook.

It seemed that bow segment was moving more SSW to NNE and had an easier time transporting down some of the LLJ. Earlier the squall line was moving more W to E which isn't going to do much for you with a 65 knot southerly LLJ.

[CT Rain]

Was that the cell we talked about late last night?

Actually I take that back... it wasn't. That was earlier. I need to download all the radar data and take a closer look.

[Damage In Tolland]

Yes but prior to it taking on that infamous no-hook.

It seemed that bow segment was moving more SSW to NNE and had an easier time transporting down some of the LLJ. Earlier the squall line was moving more W to E which isn't going to do much for you with a 65 knot southerly LLJ.

Did that move over Tolland or east of us?

[CoastalWx]

Did that move over Tolland or east of us?

That was SE of you.

[CoastalWx]

The no hook cell was at 10:30 to 11 last night and went just se of TOL. Was the other cell after? I think I may see it.

[CT Rain]

Here's the CL&P outage map from this afternoon... you can see where the damaging wind was pretty clearly.

Some towns were 75-100% in the dark with a number of trouble spots this AM.

[CT Rain]

The no hook cell was at 10:30 to 11 last night and went just se of TOL. Was the other cell after? I think I may see it.

Yeah it's gotta be the one after

[CT Rain]

The no hook cell was at 10:30 to 11 last night and went just se of TOL. Was the other cell after? I think I may see it.

The no hook cell went over Willington where it briefly popped that stronger low level meso. This was later and farther south... right near IJD.

[Wx4cast]

Yes I see what you're saying and agree that watch verification is a tricky area.

1. A portion of the public doesn't understand watch vs. warning and I agree that communication remains an issue. I think there is a level of sensitivity to this high-impact region with plenty of events going on (e.g. sports, music) usually and a lot of people.

2. What happened in the past is not exactly a point in the sense you used it in your post. There is something to pattern recognition and what a particular season tends to do, but the circumstances between yesterday's event and anything prior were much different...even if results were similar or worse.

3. Usually, wind probabilities are highest in this area and tornado probabilities that exceed wind don't occur in this part of the US.

Do I think the decisions yesterday were warranted? Not exactly...

Do I think it did them a disservice? No...

Disservice may be a poor word to use but i couldn't think of a better word. I guess what I am trying to say is to predicate a tornado watch on low-top/QLCS system is often a recipe for failure. Yes threat for isolated tornado(es) was there yesterday and often is in LCHS environment . In these situations WIND damage often rules. Another challenge in the forecast puzzle is that when tornadoes do occur in such a set up as yesterday, the TVS is often at a much lower height and often goes undetected by radar (at least here in ENY where KENX Radar is about 1400 feet).

Do we not try and predict these events? No I am not saying this. It is a a tough nut to break.

[ORH_wxman]

Here's the CL&P outage map from this afternoon... you can see where the damaging wind was pretty clearly.

Some towns were 75-100% in the dark with a number of trouble spots this AM.

Are you sure those aren't just power outages from the October storm thathaven't been restored yet?

[ChrisM]

The no hook cell went over Willington where it briefly popped that stronger low level meso. This was later and farther south... right near IJD.

I live in South Willington on the Mansfield/Storrs line and it did briefly get windier last night, a couple of good gusts right at the time that went through. Nothing to write home about though.

[CoastalWx]

The no hook cell went over Willington where it briefly popped that stronger low level meso. This was later and farther south... right near IJD.

There are two suspect cells at like 11:20 and 11:40. Subtle little outflows scene in reflectivity shooting NE. Maybe that's it.

[CT Rain]

There are two suspect cells at like 11:20 and 11:40. Subtle little outflows scene in reflectivity shooting NE. Maybe that's it.

In the BOX LSR there is a report of trees down in Windham at 11:34.

[CoastalWx]

In the BOX LSR there is a report of trees down in Windham at 11:34.

I don't have the good stuff like you do, but you can kind of see what I mean here.

http://weather.rap.ucar.edu/radar/displayRad.php?icao=KBOX∏=bref1&bkgr=black&endDate=20120919&endTime=4&duration=2

[dryslot]

Are you sure those aren't just power outages from the October storm thathaven't been restored yet?

Only in CT

[HM]

Disservice may be a poor word to use but i couldn't think of a better word. I guess what I am trying to say is to predicate a tornado watch on low-top/QLCS system is often a recipe for failure. Yes threat for isolated tornado(es) was there yesterday and often is in LCHS environment . In these situations WIND damage often rules. Another challenge in the forecast puzzle is that when tornadoes do occur in such a set up as yesterday, the TVS is often at a much lower height and often goes undetected by radar (at least here in ENY where KENX Radar is about 1400 feet).

Do we not try and predict these events? No I am not saying this. It is a a tough nut to break.

Wind probabilities are going to be highest on an EML day, too, with scattered tornadic supercells because this area is more likely to report wind damage with that scenario or with any scenario really.

But anyway, I imagine their concern was that early in the day, convection did develop (suggesting updraft strength was sufficient against the high shear) and if anything would only be moving into a more favorable environment. They mentioned the possibility of isolated supercells ahead of the line in their watch, which didn't pan out. There were distinct circulations in the line as it came through PA-NJ but nothing tight enough for a tornado. The amount of media coverage of the wind damage and the overall state of the weather yesterday will probably ease any public perception about the tornado watch issuance (who knows). I agree that the nut is tough to break. Then of course, I remember when 3 different F1 tornadoes moved across NJ one morning in 2003 that caught everyone during the commute.

[Ginx snewx]

Yeah it's gotta be the one after

I lost power last night at 1125 ish when we were hit with a very strong gust that came minutes after a 3 min complete lull. don't know if this helps define that cell.

[CapturedNature]

Yeah agreed. When comparing one utility to another, the response of WMECO vs. that of CLP for example, it's fair to criticize. But the indignant responses from some residents, played up by the local media of course, is really overblown. It's like someone who wants oceanfront property and then demands someone else pay when a wave washes into their living room. If you want to live in a heavily forested area, don't complain when branches come down on power lines. If you can't stand to be without power, move to the city or somewhere where the lines are buried. Sorry for the rant.

I hope I'm not beating the dead horse here but yesterday is a prime example of the difference between the two utilities. As a percentage of customers, CT towns had more outages than western Mass towns despite having similar winds, etc. I don't necessarily have a complaint about the response, but rather that CT seems to be wired fundamentally different than western Mass which results in a larger percentage of customers loosing power when all things are equal. It makes us (and rightly so) a laughingstock when it comes to storms and power outages. This obviously doesn't apply to special circumstances during a storm.

FWIW, my power came back on this morning after a utility truck came by and two minutes (literally) later the power was back on. If all it takes is flipping some switch, I hope they figure out some way of remotely managing these things!

</rant> & sorry if I bothered anyone.

[Damage In Tolland]

Still over 8k out of power. they called in help from NH...

[CoastalWx]

Still over 8k out of power. they called in help from NH...

Ridiculous.

[Ginx snewx]

Ridiculous.

Yep and the fight against tree trimming is partly to blame.

anyone going to the SNE weather conference will hear about it from Doug Glowacki in his presentation

"This result was confirmed by the U.S. Forest Service that

ranked Connecticut first in the Nation for Urban/Wildland Interface

density. The very high urban/wildland interface density was one of

the primary contributing factors in the degree of damage inflicted by

both Tropical Storm Irene and the October Nor’easter in 2011. This

Interface density remains our primary vulnerability to several natural

hazards including Hurricanes, Ice Storms, Wildfires, and freak

snowstorms that occur when leaves are still on trees. Only two

logical solutions are possible to reduce this vulnerability; a very

expensive tree trimming / utility hardening program or an impact by a

major hurricane. Sooner or later one of these solutions will be

implemented by us or by mother nature."

[CoastalWx]

MA is heavily forested as well. Why does CT have a problem every time a squirrel farts on top of a telephone pole?

[Ian]

Interestingly a hindcast would have verified a mod risk up into parts of CT. The southern and western parts of the mod risk didn't do so well, but it seemed to have been too far southwest on the northern end. I wonder how much is attributed to more and more spotters etc, but verbatim I suppose it was warranted.

The tornado threat was always very conditional. Given the shear though I think it was fine to put up tornado watches... not sure about the whole length of the eastern seaboard just about but in the mid-atlantic for sure. IF we could have sustained discrete updrafts out ahead of the line a strong tornado could have dropped given helicity etc. Most of the overfocus on tornadoes is the media's fault, plus public perception of the word. SPC was always pretty clear wind was the real issue and the tornado threat might not pan out. Their 10% area seemed extra large either way.

[CoastalWx]

Interestingly a hindcast would have verified a mod risk up into parts of CT. The southern and western parts of the mod risk didn't do so well, but it seemed to have been too far southwest on the northern end. I wonder how much is attributed to more and more spotters etc, but verbatim I suppose it was warranted.

The tornado threat was always very conditional. Given the shear though I think it was fine to put up tornado watches... not sure about the whole length of the eastern seaboard just about but in the mid-atlantic for sure. IF we could have sustained discrete updrafts out ahead of the line a strong tornado could have dropped given helicity etc. Most of the overfocus on tornadoes is the media's fault, plus public perception of the word. SPC was always pretty clear wind was the real issue and the tornado threat might not pan out. Their 10% area seemed extra large either way.

More and more spotters are going to make it easy to verify moderate...especially on the east coast. I mean technically I guess it would be correct, but kind of weak sauce if max gusts are 40-45kts.

[Damage In Tolland]

Yep and the fight against tree trimming is partly to blame.

anyone going to the SNE weather conference will hear about it from Doug Glowacki in his presentation

"This result was confirmed by the U.S. Forest Service that

ranked Connecticut first in the Nation for Urban/Wildland Interface

density. The very high urban/wildland interface density was one of

the primary contributing factors in the degree of damage inflicted by

both Tropical Storm Irene and the October Nor’easter in 2011. This

Interface density remains our primary vulnerability to several natural

hazards including Hurricanes, Ice Storms, Wildfires, and freak

snowstorms that occur when leaves are still on trees. Only two

logical solutions are possible to reduce this vulnerability; a very

expensive tree trimming / utility hardening program or an impact by a

major hurricane. Sooner or later one of these solutions will be

implemented by us or by mother nature."

They've asked for $100,000 per town for tree trimming. Can you imagine that..100 grand for all 162 towns and cities lol