weatherwiz

I decided to post this now b/c I did it now. We are closing in one of the more historic weather events to impact southern New England; the 40th anniversary of the October 3, 1979 Windsor Locks, CT F4 tornado. When continuing with this post, we need to keep in mind the time period this event occurred and understand our knowledge of severe weather forecasting and tornadoes was nothing compared to what it is now. In fact, the Fajita scale was a brand new implement. The set-up which produced the tornado back then was probably not really as recognized as it would be today. Anyways, just wanted to add this disclaimer as the tone of the post will be geared towards the time period of the event. Meteorological Set-up: In the days preceding October 3, 1979, a ridge was building across the western United States with a trough configured across the east. This troughing was only enhanced by a rather significant trough digging into the northern Plains on the morning of October 3. Within the initial trough was a vigorous piece of shortwave energy which dove southeast from the northern Plains and into the southern-tier of the Ohio Valley before lifting northeast towards New England. At the surface, a low pressure was tracking through western NY, however, a secondary low pressure developed across southeastern PA/NJ along a triple point. As the warm front lifted north through CT Wednesday morning, this advected a warm and moist airmass into the sate. the nearby warm front also enhanced low-level wind shear across the state: During the early afternoon, reports indicate some sun broke out of the overcast yielding surface heating. Surface heating combined with the moist low-level airmass helped to boost instability values. during this time, a supercell t'storm developed south of Long Island having a northward trajectory towards central CT. As this storm tracked north there were funnel cloud reports over Long Island and southern CT. As this supercell t'storm tracked through the CT Valley, the Valley likely enhanced the degree of low-level wind shear. The combination of instability/wind shear was just enough to yield a large and violent tornado which touched down around 3:00 PM EDT. While short-lived, the tornado caused significant destruction to Bradley Airfield, commercial businesses, as well as residential properties. In total 3 people were killed (initial reports feared perhaps hundreds may be dead) with several-hundred others wounded. At one point, this tornado was the 6th most costliest in U.S. history and caused $200 million in damage (1979 USD) ($690 million in 2019 USD (**these statistics gathered from wikipedia**). This was the deadliest CT tornado since the Great Wallingford tornado of 1878. At the time of this tornado, this was the 4th October tornado in the state of CT since records began. It also happened to be the last October tornado until 2018 when two tornadoes were confirmed in what was a historic year for CT. This was the first tornado rated F4 (it is speculated the 1878 tornado was at least this strength) and there were even arguments by some this could have been rated F5 based on the fact some structures were completely wiped off their foundations. Thoughts on the event: It is pretty remarkable such a setup was able to produce. It's a shame more weather data isn't available from then. Despite a lack of EML, there must have been some pretty vigorous 0-3km CAPE in place which resulted from breaks of sunshine yielding strong sfc heating. I forget the reports but I think temperatures may have spiked into at least the upper 70's...maybe even just above 80? Just looking at the upper-air pattern, however, wind shear certainly was supportive for rotating updrafts. The state was also in perfect positioning with respect to the triple point with the triple point passing right over the state. Such an event is so rare, but it shows what can transpire when all ingredients come together...the rarity of such an event also shows how difficult it is for this to happen.

Thank you for that insight!

I'm always left out

i don’t see a fight think just B I U a smiley face, a chain a magnifying glass on a piece of paper and an areowarrow

Wtf?? I can’t read or see anything in typing in mobile. I for sure thought BDL would get into mud 80’s and what a fail call on ORH lol

I think it has to do with density...cold air being much more dense moving over the warm air just above the lakes is less dense so it increases the degree of force. then obviously strong winds are going to get the water moving and perhaps the temp gradient will yield some decent lapse rates and mixing...similar to LES.

Thank God storm mode will be linear and things will be parallel to the flow...otherwise this could have been a nasty tornado outbreak over a localized area across NE KS into MO and IL

I remember when Kevin won once and was pissed

That was always a ton of fun. The sub-forums though sort of killed that off IMO.

You know what's depressing...looking at the CAPE maps through the entire run and starting to see no big CAPE across the country My favorite thing to do with the 12z/0z runs is animate the CAPE maps during the summer.

Going to start a low CAPE/high shear convective threat on Sunday for Wednesday. Sorta kinda like the look. Now that we're getting into the fall season we transition from big CAPE severe events to big shear severe events. I always have mixed emotions with these setups.

I think I briefly mentioned yesterday the lack of mixing being shown on the GFS. 12z run today at BDL tomorrow only seems to mix to just shy of 4,000' and yields a temperatures just a bit above 80. I would think we should be able to mix pretty close to at least 4500' which pushes temps well into the mid 80's. If we can get closer to 5,000 that gets BDL to 90. Both NAM and GFS have a decent inversion from like 4500 -5000'

WOW... the SPC went from 5% wind and <2% TOR with the 13z outlook to 15% hatched wind and 5% TOR with the 1630z outlook across the MO Valley into IL

I wish I understood MT and AAM better..well all the different torques and applying them and enough to make plots.

Could be an opportunity for a few strong t'storms to work into southern VT, NW MA...maybe even southern NH.

OMG...I want that!!!

That needs to be a tee-shirt.

Well said. subsequently why the term is stupid

It's similar to using terms like warm, cool, cold, hot. Would you call 73 in July warm? no would you call 73 in January warm? yes

THIS!!! Although this is why the term torch is kinda stupid...there is no scientific definition to it so it's completely open to interpretation. Person A may think torch only applies to a temperature threshold (say 90+) while person B applies it to a deviation from the average. At the end of the day it should really be applied to a deviation.

Departures from the past week have been pretty decent: I remember back in August I was saying I think September could be the warmest on record across many sites...obviously that is not panning out...and not even close. I thought the pattern we've seen the past week was going to be more predominant this month but it didn't work out that way...delayed but not denied I guess.

It is going to rip at GTF for many hours Saturday night through Sunday. Although there will be some dry air/subsidence screw zones. Some moose will be unhappy

I've always been extremely curious about how this works. Perhaps @OceanStWx has gone into great depth about this before, but when it comes to these snow map, if they are all computer generated with human tweaks, how exactly are they derived? Is it a blend of numerous forecast models, an in-house model, one particular model? And what algorithms are used in them...or are they just derived from the model snowfall algorithms (like 10:1 ratio or Kucheria). But then with the human tweaking...across this region that can't be particularly easy, especially if you have little experience/knowledge of the terrain and geographical influences.

I do agree...mobile version has not been very friendly, particularly with formatting the past few months (maybe longer). Whenever there are images posted it throws the mobile all out of whack. I've also noticed that sometimes when you post it saves what you posted in the text box and you have to clear editor.

maybe you had too much to drink?