Severe Weather Threat Week...so many threats!!!

[Torch Tiger]

12z gfs is loaded with threats!  let's go!

[IowaStorm05]

I do not certify this is 100 per cent accurate, especially for upstate NY, VT and NH since I don’t know those areas as well. But here you go.

 

[SouthCoastMA]

2 minutes ago, IowaStorm05 said:

I do not certify this is 100 per cent accurate, especially for upstate NY, VT and NH since I don’t know those areas as well. But here you go.

 

seems high, tbh

[IowaStorm05]

4 minutes ago, SouthCoastMA said:

seems high, tbh

It might be a bit high, but I guess one could say this is what it’s like on a good year? I can make another map after deeper research, or after critique, this one I just did based on what I know up to this point without more research.

On looking twice I could see the CT coast being overestimated in this. You might not get such favorability until you’re further west than I have it.

[Cyclone-68]

I just hope we’re not depending on a fricken warm front again to deliver the goods

[dendrite]

I'd be lucky if I've had 5 so far and half of those are just weak rumbles.

[Great Snow 1717]

48 minutes ago, IowaStorm05 said:

It might be a bit high, but I guess one could say this is what it’s like on a good year? I can make another map after deeper research, or after critique, this one I just did based on what I know up to this point without more research.

On looking twice I could see the CT coast being overestimated in this. You might not get such favorability until you’re further west than I have it.

Plus the hit or miss aspect of thunderstorms affects the total. . This past sunday a storm passed a few  miles to the north. It went into the books as a thunderstorm day for parts of Salem NH and parts of  Haverhill Ma but not for Methuen

[IowaStorm05]

32 minutes ago, Great Snow 1717 said:

Plus the hit or miss aspect of thunderstorms affects the total. . This past sunday a storm passed a few  miles to the north. It went into the books as a thunderstorm day for parts of Salem NH and parts of  Haverhill Ma but not for Methuen

Interesting. 

[weatherwiz]

I think those are quite high. Maybe by like 30%

[tamarack]

35 minutes ago, IowaStorm05 said:

I do not certify this is 100 per cent accurate, especially for upstate NY, VT and NH since I don’t know those areas as well. But here you go.

 

For the 3 places in Maine with more than 3 years record:

Fort Kent:  9.8 yr, Avg 12.2/yr  Most: 17, Least 6.  Top month: July, 3.8.  Least:  Feb, Dec, zero   
Had 4 SVR (Hail/wind) and 2 near SVR

Gardiner: 12.6 yr, Avg 13.0/yr   Most:  22, Least 7.  Top month: June, 3.3.  Least:  Jan, zero   
Maybe 2 near SVR (lightning/RA) as the strongest would miss.  Tornado in the next town.

New Sharon: 24.2 yr, avg 15.0/yr  Most: 23, Least 8.  Top month: July, 4.5.  Least: Novie, zero.  (July 2022, one so far, not included.) 
2 near SVR (Wind/RA).  Defoliating hail 8/30/07 only 6-8 miles to SE.

We moved from Gardiner to New Sharon in mid-May 1998, and recorded thunder days in each place.  Thus, May 1998 is counted as part of both places.
My 3 years in BGR are omitted, both for small sample size and because of being away for much of summers 1974 (Forestry summer camp, 6 weeks) and 1975 (field research all summer).

[powderfreak]

EF-1 Confirmed in Vermont yesterday.

https://forecast.weather.gov/product.php?site=BTV&issuedby=BTV&product=PNS&format=CI&version=3&glossary=0

[IowaStorm05]

1 hour ago, tamarack said:

For the 3 places in Maine with more than 3 years record:

Fort Kent:  9.8 yr, Avg 12.2/yr  Most: 17, Least 6.  Top month: July, 3.8.  Least:  Feb, Dec, zero   
Had 4 SVR (Hail/wind) and 2 near SVR

Gardiner: 12.6 yr, Avg 13.0/yr   Most:  22, Least 7.  Top month: June, 3.3.  Least:  Jan, zero   
Maybe 2 near SVR (lightning/RA) as the strongest would miss.  Tornado in the next town.

New Sharon: 24.2 yr, avg 15.0/yr  Most: 23, Least 8.  Top month: July, 4.5.  Least: Novie, zero.  (July 2022, one so far, not included.) 
2 near SVR (Wind/RA).  Defoliating hail 8/30/07 only 6-8 miles to SE.

We moved from Gardiner to New Sharon in mid-May 1998, and recorded thunder days in each place.  Thus, May 1998 is counted as part of both places.
My 3 years in BGR are omitted, both for small sample size and because of being away for much of summers 1974 (Forestry summer camp, 6 weeks) and 1975 (field research all summer).

Thank you for your Information. Having taken a look at that, and memory of other maps, I just made this:

Again I know the numbers aren’t perfect, but even if they’re off by 30 per cent or something, since I didn’t live in Maine, it gives a good comparison and idea of what the ocean and latitude is doing to your thunderstorms as you go from one part of New England to another.

[Torch Tiger]

...Northeast...
   Scattered showers and a few thunderstorms are possible over
   western/northern NY during the morning.  Cloud breaks and strong
   heating east of this convection will result in strong
   destabilization by early afternoon.  A seasonably moist airmass
   featuring upper 60s to lower 70s dewpoints will become moderately
   unstable.  The erosion of a weak cap will likely occur over the
   higher terrain of VT/NH and near the front over central NY with
   scattered storms likely by early-mid afternoon.  Forecast soundings
   show effective shear 25-45 kt supporting organized storms, including
   bands and probably several supercells.  The main threats will be
   damaging gusts and large hail, but an isolated tornado risk could
   also materialize over New England where shear will be strongest. 
   This activity will likely move to the coast by the evening.

[weatherwiz]

Probably be a NNE ordeal 

[Torch Tiger]

1 hour ago, weatherwiz said:

Probably be a NNE ordeal 

Yeah much better chances, but at least we still have the remnant EML showing up (and decent hodos).  If something gets going it'll be pretty good.

[Cyclone-68]

Does anyone think we can at least generate an “enhanced risk” from Thursdays threat? 

[Torch Tiger]

3 minutes ago, Cyclone-68 said:

Does anyone think we can at least generate an “enhanced risk” from Thursdays threat? 

Need 10% tor or 30% wind/hail probs for ENH, iirc.  Maybe NNE?  Doubtful for SNE I'd say.

Actually Sunday may have a better chance of a more widespread wind/squall line type deal?  Temps in the 90's, 50kt h7 winds and front coming in.  

[eekuasepinniW]

I don't think I've had 20 thunderstorms in the last 5 years combined.

[mreaves]

5 hours ago, IowaStorm05 said:

Thank you for your Information. Having taken a look at that, and memory of other maps, I just made this:

Again I know the numbers aren’t perfect, but even if they’re off by 30 per cent or something, since I didn’t live in Maine, it gives a good comparison and idea of what the ocean and latitude is doing to your thunderstorms as you go from one part of New England to another.

Looks like a snow total forecast

[Hoth]

39 minutes ago, eekuasepinniW said:

I don't think I've had 20 thunderstorms in the last 5 years combined.

And half of those have been in winter.

[Chrisrotary12]

Remember when today was a marginal risk for NY & NNE?

[IowaStorm05]

1 hour ago, mreaves said:

Looks like a snow total forecast

For Late August, after we get that massive volcano eruption with requisite chemical composition release.

[Cyclone-68]

Is it fair to say the enthusiasm level for tomorrow has dropped somewhat? NWS seems to have it as a pedestrian event 

[tamarack]

17 hours ago, IowaStorm05 said:

Thank you for your Information. Having taken a look at that, and memory of other maps, I just made this:

Again I know the numbers aren’t perfect, but even if they’re off by 30 per cent or something, since I didn’t live in Maine, it gives a good comparison and idea of what the ocean and latitude is doing to your thunderstorms as you go from one part of New England to another.

Glad to help.  Probably too fine distinctions for a broad-based map, but there are some mesoscale differences:  the NNE mountains seem to generate more TS than flatter regions, and the coastal areas east of Penobscot Bay are graveyards for convection.
Small sample size, but I found it odd that my Fort Kent experience included fewer storms but more severe ones.  The northern 25% of Maine seems to have more than its share of damaging storms.   On September 30, 1986, straight-line winds caused a 600-acre blowdown which ended by toppling trees into Square Lake.  The same townships (T16R6 and T16R5) had several blowdown patches, the largest 70 acres, in 2005.  Six years later an EF-0 damaged buildings in the town of Eagle Lake then became straight-line winds that flattened about 200 acres near the north shore of Eagle Lake itself.  2012-13 saw EF-0/1s in Oxbow and near Long Lake (the Aroostook Long Lake) and destroyed several hundred acres in the northern part of Baxter Park.  And of course, the biggest ones of all were near Katahdin during the 1970s.  12-15" of pasty November snow plus wind flattened about 3,000 acres south of the mountain in 1974 (and 3 years later fire burned most of that area of well-seasoned jackstraws.)  Then in 1979 an October storm tipped over another 3,000 acres of spruce-fir a dozen or so miles NW of the 1974 event - from the air that later event looked like lodged oats after an August downpour.

[weatherwiz]

8 minutes ago, Cyclone-68 said:

Is it fair to say the enthusiasm level for tomorrow has dropped somewhat? NWS seems to have it as a pedestrian event 

This is probably more of a NNE event. This actually kind of sucks because there looks to be a remnant EML or plume of steeper lapse rates which moves overhead tomorrow. But bulk shear looks to weaken with the main shortwave well into southeast Canada so heights rise. This could be a pretty decent wind event though for NNE. I wouldn't be surprised to see an enhanced risk at some point. 

[Torch Tiger]

Seems to me threat level has been and is pretty low south of the Pike/BOS/ORH.  I still think WNE and north of the pike could see some action.  Like Wiz said, the main s/w is curling like N and NNE through ONT/QC instead of more east, that would have helped southern areas. With the marine taint creeping in, that will probably supress convection the more coastal southern areas (and maybe enhance it a bit further north if convection intersects)

[Torch Tiger]

HRRR is basically dry south of the pike.

[weatherwiz]

3 minutes ago, Torch Tiger said:

Seems to me threat level has been and is pretty low south of the Pike/BOS/ORH.  I still think WNE and north of the pike could see some action.  Like Wiz said, the main s/w is curling like N and NNE through ONT/QC instead of more east, that would have helped southern areas. With the marine taint creeping in, that will probably supress convection the more coastal southern areas (and maybe enhance it a bit further north if convection intersects)

Agreed...seems like N of the Pike event. Moreso like New Hampshire into Maine. 

[weatherwiz]

I wonder if we can muster up some supercells tomorrow. The lack of stronger forcing will work to limit storm coverage (which would increase potential for supercells) but on the other hand, the very weak forcing will make it difficult for supercell structures to probably become mature and sustaining. With this I think we'll see a few very nasty cells tomorrow afternoon. 

I may take back my prediction of an enhanced risk...not sure the potential is widespread enough (wind damage) to warrant it (except in Maine). 

[Torch Tiger]

A cold front...actually more of a dewpoint front...will move
eastward into this hot unstable air mass Thursday afternoon and
evening. Wind fields aloft will strengthen as a weak mid-level
trough moves through as well, with 30-40 kt of deep layer shear.
Surface-based CAPE of 2000-3000 J/kg and MLCAPE of up to 1500
J/kg indicates plenty of instability. One thing lacking for
severe weather will be relative lack of height falls. But model
vertical motion is strong and the instability and shear should
be sufficient for the development of strong to severe
thunderstorms from as early as 11 AM or Noon and lasting into
the mid-evening hours.

The CAMs indicate potential for broken line segments with the
main focus across CT and western and central MA, where updraft
helicity swaths are focused. Damaging wind appears to be the
primary severe threat, but an isolated tornado cannot be ruled
out in those areas. The least threat is in RI and southeast MA,
where the majority of the day should be dry, but remnant
showers and thunderstorms may move through late in the day or
evening.