May 2026 Obs/Discussion

[Torch Tiger]

20 minutes ago, vortex95 said:

I will say this event was rather impressive given the slightly anticyclonic flow aloft.  Usually w/ such hot temps and that kind of flow aloft, it remains capped.  One thing though the cell coverage did to rage into a SQLN at first.  Cells were small clusters but intense.

mesos were so-so, but you could see how a very solid event could get going along I-90 ish 

[CoastalWx]

Euro AI getting wetter this weekend 

[CoastalWx]

4 hours ago, Torch Tiger said:

mesos were so-so, but you could see how a very solid event could get going along I-90 ish 

I thought hrrr had a good signal. I also noticed storms took off once they hit S coast seabreeze.

[vortex95]

Wxwiz should make a New England version!
https://atlas.niu.edu/alerts/
 

[Baroclinic Zone]

Sprinkles yesterday

[Damage In Tolland]

Euro gonna bust badly for MDW

[Chrisrotary12]

7 hours ago, vortex95 said:

I may have mentioned this before, but there is something physical about the NH seacoast that make tstms better or intensify here.  Today was no exception, and two waves back-to-back!  Isles of Shoals gusted to 63 mph.

I realized this anecdotally as a kid being at Hampton Beach on vacation each summer, but that can have bias b/c everything is larger than life when you are kid, and any beach view is going to look more impressive overall for storms.

Once the SPC hourly mesoanalysis product came out, I started to watch closely.  What seems to be a factor is that there is at times locally higher 0-1 or 3 km shear/helicity on or just off the NH coast.  Despite the cool ocean temps, a sea breeze here appears to result in intensification of storms in the area.  Not necessarily svr, but a line of showers suddenly becomes active w/ CGs and weak mesos form, as one example.  I've seen too many times for it to be just coincidence.

What may be happening is this - first, once you get to the MA/NH border, any marine stabilization from S of SW winds coming S of LI basically becomes a non-factor.  Second, and most importantly, the low-level winds over Cape Ann are briefly lessened, then pick up again once over the ocean, only to slow again once reaching the ME coast.  So this sets up locally better low-level shear/helicity profile for cells to feed off of.  For years, I have informally called it "The Hampton Effect."

One of most outstanding example was on May 21, 2006.  A nasty bowing squall line was ripping across central/southern New England.  Once the northern part of the line got E of ASH, it gusted out enough that the leading edge cells weakened considerably, so there was nothing but RW-/RW and a bit of thunder.  Once that outflow got to I-95, an isolated supercell developed very quickly and produced tornado at Hampton Falls.  Lasted only about 30 sec, but it was clearly visible as a stout narrow column. See story here:
https://www.timesargus.com/news/weather-service-confirms-tornado-hit-coastal-n-h/article_ed848d36-9e43-5117-aae8-97098039f6ab.html

A waterspout also occurred not far offshore from Rye Beach.

When I saw this and the radar loop, I said, "you've GOT to be kidding me, since when in New England does a tornadic supercell form on a edge of a gust from from a decaying squall line?!"  And SSTs on the NH coast are still pretty cold in mid-May, yet that did not impede things at all.

I think the only other time I was flabbergasted like this was the two mini-supercell tornadoes occurred in the Brunswick ME area on Thanksgiving in 2005.  This was after a couple of inches of snow has just fallen here in the previous several hours!
 

Thank you for this. I noticed the Hampton Effect a few years back after a buddy moved to Dover and he cashed every thunderstorm while ASH consistently gets nothing. I’ve been obsessed with it since because it is so consistent. 

[dendrite]

Happy 7am!

[Damage In Tolland]

NAM is only S coast special today . BDR to CC

[kdxken]

24 minutes ago, dendrite said:

Happy 7am!

Glad I installed at least in the bedroom. Was going to just go with the window fan. Never cooled off.

[jbenedet]

 The persistence continues with often world’s apart differences in sensible weather between here and eastern Long Island. Jet still meandering overhead.

Memorial Day weekend gonna be a lot of GWDLT…

 

 

[jbenedet]

27 minutes ago, dendrite said:

Happy 7am!

This is just a feature now.

 

Careful what you wish for. 60’s for highs looking great. Can’t wait for the return.

[jbenedet]

29 minutes ago, dendrite said:

Happy 7am!

 

Just give us a faint sw flow and it’s Florida.

Gotta love how fossil fuel emissions all the focus

 

meanwhile…

 

All those data centers popping up

[dendrite]

Those are the warmest 7am May temps at BML and IZG ASOS since they were commissioned 

[Baroclinic Zone]

12 minutes ago, jbenedet said:

 

Just give us a faint sw flow and it’s Florida.

Gotta love how fossil fuel emissions all the focus

 

meanwhile…

 

All those data centers popping up

Just look up Stratos Hyperscale Data Center. Horrifying.

[HIPPYVALLEY]

5 minutes ago, Baroclinic Zone said:

Just look up Stratos Hyperscale Data Center. Horrifying.

Yep, the environmental impacts of that will be mind-boggling.  

[40/70 Benchmark]

1 hour ago, Damage In Tolland said:

Euro gonna bust badly for MDW

Without looking at anything, and in the absence of any context whatsoever, I will venture out on a limb and guess you are thinking warmer than forecast?

[Chrisrotary12]

1 hour ago, dendrite said:

Happy 7am!

Was pretty gross leaving gym at 7am this morning. 

[Brian5671]

1 hour ago, jbenedet said:

 The persistence continues with often world’s apart differences in sensible weather between here and eastern Long Island. Jet still meandering overhead.

Memorial Day weekend gonna be a lot of GWDLT…

 

 

Tough forecast for some areas with that sharp rain cutoff.   Still crappy everywhere but dry would be more tolerable than an all day stratiform rain.

[Damage In Tolland]

32 minutes ago, 40/70 Benchmark said:

Without looking at anything, and in the absence of any context whatsoever, I will venture out on a limb and guess you are thinking warmer than forecast?

Drier. Not rain free but not 3 days of rain and 40’s like it’s been showing 

[WinterWolf]

1 hour ago, Damage In Tolland said:

NAM is only S coast special today . BDR to CC

We weren’t supposed to get much yesterday and we got drenched.  I don’t trust the modeling in these. 

[WinterWolf]

47 minutes ago, HIPPYVALLEY said:

Yep, the environmental impacts of that will be mind-boggling.  

Everybody wants social media(anll the different forms)  and memes and AI….these are the consequences to such things. 

[dendrite]

He’s baaaaack

[Typhoon Tip]

58 minutes ago, dendrite said:

Those are the warmest 7am May temps at BML and IZG ASOS since they were commissioned 

blah blah blah.. !

[codfishsnowman]

39 minutes ago, Chrisrotary12 said:

Was pretty gross leaving gym at 7am this morning. 

This weather sucks for mid to late May

[weatherwiz]

10 hours ago, vortex95 said:

Latest NAM/GFS MOS shows 87-88.  So where do you think the NBM is getting 95 from?  2m temps?  But I checked the HRRR/NAM/GFS/ECMWF, those do not show any higher than 89-90.

The 7z run knocked BDL down to 92 for today but gotta say...the NBM did quite well for yesterday's temps. 

In the case of today, the only thing I can think of is there was a good bit of guidance perhaps slower with the cold front. I want to read more into what changes were made with NBMv5...I briefly did this a few weeks ago and there was mention this version was even more accurate with temperatures. I think the NBM may have a more "accurate" mixing capability versus traditional MOS and also isn't as scaled or tied into climo.