Convective Thread

[jbenedet]

[CoastalWx]

Fail.

[OceanStWx]

Just now, CoastalWx said:

Fail.

[jbenedet]

Really frustrated..that storm developed to have a beautiful wall cloud, but I can't UL the pics for some reason...

[weatherwiz]

Not a fan of how the 18z GFS/NAM came out for Tuesday

[CoastalWx]

22 minutes ago, OceanStWx said:

Days are getting shorter.

[weatherwiz]

Just now, CoastalWx said:

Days are getting shorter.

I don't need to be hearing this 

[OceanStWx]

7 minutes ago, CoastalWx said:

Days are getting shorter.

 

Maybe if we're lucky we can squeeze one more good severe event out this summer.

[weatherwiz]

Just now, OceanStWx said:

 

Maybe if we're lucky we can squeeze one more good severe event out this summer.

better be in August and August better be active

[weatherwiz]

What sucks is how we can't get an EML into here.  700/500mb pattern hasn't been horrid for them its just the plumes fizzle out once they get into the Great Lakes region.  bull****

[weatherwiz]

45 minutes ago, jbenedet said:

that is sick!

[OceanStWx]

Just now, weatherwiz said:

What sucks is how we can't get an EML into here.  700/500mb pattern hasn't been horrid for them its just the plumes fizzle out once they get into the Great Lakes region.  bull****

Persistent trofing is no good for sneaking EMLs in the backdoor. 

[weatherwiz]

6 minutes ago, OceanStWx said:

Persistent trofing is no good for sneaking EMLs in the backdoor. 

they keep trying but no luck.  Thursday though looks like we could maybe luck out with a weakening plume moving overhead.  Looks like a potentially decent s/w too and strong westerlies.  Could be an active week if timing of things work out.

[OceanStWx]

On 7/1/2017 at 6:57 PM, eekuasepinniW said:

 

Sorry, but I'm just catching up with this thread and I still don't have any pants on.

But this is a great time lapse for folks who want to see shear in action. Watch early on in the video how the lowest level clouds are moving left to right (I'm assuming this is roughly south to north). Just above that scattered cloud deck is another, thicker cloud deck that is moving more towards the camera (I'm assuming this cam is pointing more or less W or WSW?). Those cloud levels don't look all that far apart, and there is plenty of directional shear between them.

[OceanStWx]

On 7/2/2017 at 10:12 AM, Baroclinic Zone said:

Maybe someone can elaborate on this but is that area up in ME conducive to spin-ups with the mountains to the west?  Seems like the down-sloping off of them could help enhance storms.

It is a hot spot for us. I think some factors that make it so are that moisture tends to pool just south of the mountains, you can get nice and warm in that SE NH/SW ME area, and winds subtly back up against the terrain.

On 7/2/2017 at 9:51 AM, wxeyeNH said:

I was a bit surprised that the Storm Prediction Center decided to go with a Severe Thunderstorm Watch and not a tornado watch for C/NNE yesterday.   Really ended up being not so much of a severe day as far as wind, hail and tons of lightning but a heavy rain day with brief windups.  That Sebego Lake tornado/waterspout could have been much worse.  A few boats in the path and a few drownings would have caused all kinds of speculation as to why a tornado watch was never issued. Even if a warning was not put up in time a watch would have gained peoples attention as its pretty rare up here.  It seemed to me it was the discreet cells rapidly moving north as the main line moved east.  Did NNE dodge a built yesterday?

I may not be particularly thrilled with SPC at the moment, but when they went 5% for tornadoes up here think of it in these terms: the climo average percent chance of a tornado within 25 miles of a point around Sebago is roughly 0.15% on July 1st. So that 5% represented about 33 times more likely that you would see a tornado within 25 miles. 

[OceanStWx]

Running some of the numbers from the graphics Ryan used in his write you can see that we were definitely edging out on the tail of the distribution for storm environments in Maine.

Now it's a small sample size of course, but here are some of the things SPC looks at for the historical tornado environment: STP was 1, supercell composite was 8, effective shear 40 knots, MLCAPE 1000, MLLCL 750 m, effective helicity 300-400(!). Based on the distribution around Sebago Lake those numbers would be in order 75th percentile, max, near the median, 75th percentile, 25th percentile (remember low numbers are better with LCLs), and max. 

Not bad. GYX also had its first TDS spotted on radar, the second Bridgton tornado I believe. There are a couple others in the "maybe" category, but this one is for sure. And it happened in a SAILS scan, so we would've missed it otherwise.

[ice1972]

What a great light show on the Outer Banks tonight.....so great.....first visit

[kdxken]

8 minutes ago, ice1972 said:

What a great light show on the Outer Banks tonight.....so great.....first visit

Awesome place.

[powderfreak]

Can hear distant thunder with the approaching line of precipitation.

This is the 4th line to traverse the area today!  It is pretty crazy to have 4 different areas of precipitation of the linear variety pass through.

Nothing more than some heavy rain and some thunder...but sort of like going getting 4 hits in baseball with 3 singles and 1 double.  Solid effort and a very active day.  No memorable hits, though.  Solid soaking across the area again.

8:30am

I was at the ski resort on the upper elevations of the Toll Road (along the county line on the rad image) and this was the most impressive of the four today for me.  Small branches and water runnels on the ground.

This next one was around 2pm in the afternoon and had some very vivid lightning and thunder, with the heavy stuff remaining southeast of the ski resort...though decently heavy rain did clip the generally Village area.

Some distant thunder with this line...least impressive at home, but the office got another couple downpours.

Now I've heard more thunder and it just started pouring.  This is the radar from a little while ago while it was approaching.

 

 

 

 

[j24vt]

3 hours ago, powderfreak said:

Can hear distant thunder with the approaching line of precipitation.

This is the 4th line to traverse the area today!  It is pretty crazy to have 4 different areas of precipitation of the linear variety pass through.

Nothing more than some heavy rain and some thunder...but sort of like going getting 4 hits in baseball with 3 singles and 1 double.  Solid effort and a very active day.  No memorable hits, though.  Solid soaking across the area again.

8:30am

I was at the ski resort on the upper elevations of the Toll Road (along the county line on the rad image) and this was the most impressive of the four today for me.  Small branches and water runnels on the ground.

This next one was around 2pm in the afternoon and had some very vivid lightning and thunder, with the heavy stuff remaining southeast of the ski resort...though decently heavy rain did clip the generally Village area.

Some distant thunder with this line...least impressive at home, but the office got another couple downpours.

Now I've heard more thunder and it just started pouring.  This is the radar from a little while ago while it was approaching.

We were shooting a fireworks show off Edson Hill tonight.  Set up in between the storms and finished shooting the show just before the last line went through.

 

 

 

 

[weatherwiz]

Tuesday doesn't look as solid as it did a few days ago.  S/w looks like garbage 

[wxeyeNH]

Below is the day's timelapse from July 1rst.  So much shear going on.  SE wind at my elevation but SW/W just above.  I was right on the edge of the heavy rain/storms all day.  Lots of sun just to the south, flooding rain 25 miles north.  I ended with 1".   The heavy storms that caused all the flooding just to my norht are at the end of the clip.  At 1:40 into the video almost looks like a brief spin up.  Very busy atmosphere that day.

https://video.nest.com/clip/c9e2f0616c1f4e58ae16d6508c189332.mp4

 

 

[Typhoon Tip]

14 hours ago, OceanStWx said:

It is a hot spot for us. I think some factors that make it so are that moisture tends to pool just south of the mountains, you can get nice and warm in that SE NH/SW ME area, and winds subtly back up against the terrain.

I may not be particularly thrilled with SPC at the moment, but when they went 5% for tornadoes up here think of it in these terms: the climo average percent chance of a tornado within 25 miles of a point around Sebago is roughly 0.15% on July 1st. So that 5% represented about 33 times more likely that you would see a tornado within 25 miles. 

Mixed emotions on that policy..

On the one hand, they are servicing the public at large .. A public that is utterly non-privy to that whole line of numerical/statistical logic, and therefore are going to be completely oblivious to the most important number in that bold text above:  the "33 times more likely..."    Naturally, the question becomes, what's the point of telling J.Q. Fisher to be careful venturing out on Lake Sabago because there's a 5 percent chance of anything.   In other words, from a purely PR perspective meets with the intent of it all... that's asinine. 5 percent doesn't resonate.

 

On the other hand, ... I'm not sure those percentages were originally designed for public consumption?  at least not in that way... I think the original assessments from SPC, like a heritage going back before every electron was made accessible to the Web ... was for internal channels that were supposed to then notify their audiences appropriately..  There's that, but also, part of me kind of wants to go Darwinian on civility and those that can't do the based math and/or reasoning need to actually go out on Lake Sabago and do us all a favor... heh.

[Typhoon Tip]

Not that anyone cares or asked ...but ... yesterday was awesome!  If one was not getting clocked by some decent outflow winds, the occasional CG and giant jungle drop visibility restricting rains, ..they were adjacent to some absolutely stunning cloud tapestries - both from underneath and sun exposed CB towers!..

That's not the first day of that sort of "luck" ...and I say luck, because we've had a lot of those this summer thus far, an abnormally large number of them (imho) for our region.  We may not be getting "Munsoned" by these convective days ...but it is a steady diet of entertainment for those of us that appreciate weather phenomenon.  There have been plenty of far more patience-trying dullard summers of lore.

We may not get the big historic heat wave this summer - in fact, we haven't had one in decades ...maybe we can't... Seems you have to go back to 1988 to get a truly hot summer. either way, convection chances every two to three days with 85/52 intervening is an awesome summer.

[CoastalWx]

The areas north of the pike have gotten a few hits over the last couple of weeks. Not so much to the south as of yet, except for Cape Cod the other day. 

 

Surprised Wiz hasn't commented on the 3KM NAM for Tuesday. Some impressive kinematics as modeled.

[WxBlue]

40 minutes ago, Typhoon Tip said:

Mixed emotions on that policy..

On the one hand, they are servicing the public at large .. A public that is utterly non-privy to that whole line of numerical/statistical logic, and therefore are going to be completely oblivious to the most important number in that bold text above:  the "33 times more likely..."    Naturally, the question becomes, what's the point of telling J.Q. Fisher to be careful venturing out on Lake Sabago because there's a 5 percent chance of anything.   In other words, from a purely PR perspective meets with the intent of it all... that's asinine. 5 percent doesn't resonate.

 

On the other hand, ... I'm not sure those percentages were originally designed for public consumption?  at least not in that way... I think the original assessments from SPC, like a heritage going back before every electron was made accessible to the Web ... was for internal channels that were supposed to then notify their audiences appropriately..  There's that, but also, part of me kind of wants to go Darwinian on civility and those that can't do the based math and/or reasoning need to actually go out on Lake Sabago and do us all a favor... heh.

I was in Norman this past May and was able to stop by SPC office. Their chief of forecasting operations told me that SPC is undergoing a large shift in how they forecast their outlooks and assign hazard probabilities because their forecasts are becoming much more visible to the public. They're also getting better at forecasting severe events and are becoming more aggressive with their forecasts since we now have the technology to narrow down the threat area to ensure the probability would verify. That's why we're seeing more high risk days in the south.

[weathafella]

Managed to elude it all yesterday during the drive from Quebec back to Boston but saw some good cg in the distance along with mammatus overhead north of CON.

 

 

 

 

 

 

[weatherwiz]

Models wavering on strength of the s/w Tuesday.  Timing right now looks a tad fast but we could have a few decent storms around 

[OceanStWx]

2 hours ago, Typhoon Tip said:

Mixed emotions on that policy..

On the one hand, they are servicing the public at large .. A public that is utterly non-privy to that whole line of numerical/statistical logic, and therefore are going to be completely oblivious to the most important number in that bold text above:  the "33 times more likely..."    Naturally, the question becomes, what's the point of telling J.Q. Fisher to be careful venturing out on Lake Sabago because there's a 5 percent chance of anything.   In other words, from a purely PR perspective meets with the intent of it all... that's asinine. 5 percent doesn't resonate.

 

On the other hand, ... I'm not sure those percentages were originally designed for public consumption?  at least not in that way... I think the original assessments from SPC, like a heritage going back before every electron was made accessible to the Web ... was for internal channels that were supposed to then notify their audiences appropriately..  There's that, but also, part of me kind of wants to go Darwinian on civility and those that can't do the based math and/or reasoning need to actually go out on Lake Sabago and do us all a favor... heh.

I don't disagree with that sentiment. 5% just goes way over the head of most people when they hear about these outlooks. As far as internally, those numbers are extremely robust and appropriately delineates run of the mill type days from larger events. I think part of the problem was the NWS always sort of having a wall up between themselves and the public. We serve the public, but we didn't always interact well with the public. Now there is a much larger push to educate at least the decision makers on what our products mean. 

1 hour ago, WxBlue said:

I was in Norman this past May and was able to stop by SPC office. Their chief of forecasting operations told me that SPC is undergoing a large shift in how they forecast their outlooks and assign hazard probabilities because their forecasts are becoming much more visible to the public. They're also getting better at forecasting severe events and are becoming more aggressive with their forecasts since we now have the technology to narrow down the threat area to ensure the probability would verify. That's why we're seeing more high risk days in the south.

I think we're already seeing the signs of this, with smaller percentage areas. We are able to narrow down higher threat areas better than we used to, and SPC is using that to their advantage by drawing smaller, higher percentage zones within the broader severe weather threat area.

[OceanStWx]

2 hours ago, CoastalWx said:

The areas north of the pike have gotten a few hits over the last couple of weeks. Not so much to the south as of yet, except for Cape Cod the other day. 

 

Surprised Wiz hasn't commented on the 3KM NAM for Tuesday. Some impressive kinematics as modeled.

The 12z run even backs the winds in the CT River Valley like a 

It runs a nice supercell practically into WeHa.

But morning convection could be a wrench in the works. Pretty close to NSFW forecast soundings though.