vortex95

40-48 hr the 00z HRRR shows it taking on more ST characteristics w/ a more focused core wind field. RRFS does this but it take more than 24 hr after this time, and the low just meanders around to the S of us for the entire 84 hr period! Lots of time to do odds stuff! @WxWatcher007 I know will be closely tracking the exact sfc low position relative to the SSTs!

Get them here! https://www.ncei.noaa.gov/gibbs/

00z HRRR shows the E Coast low taking on more ST characterists 40-48 hr as a inner core contracted wind field develops. RRFS it take over 24 hr longer to do this.

On Wed, five sites in ME/Quebec set all-time record high pressures for Sep. @CoastalWx take note. It's an exceptional pattern! Frenchville Montreal Quebec City Val D’Or Chibougamau-Chapais.

Just a nit from the 25/03z discussion for Nolo: Nolo is expected to pass near or just south of the Big Island of Hawaii on Saturday as a major hurricane. It's closet approach is about 125 mi S of the srn tip of the Big Island. Is that really "near or just S" for such a distance, esp. for an avg size TC? The wording makes it sounds closer than it really will be. That's a big deal when it comes to winds in a TC, esp. a strong one.

Don't even get me started w/ Sandy! I'll spare you all a rant write-up on that! One thing I will say, at a SNE conference I think 12 years ago, one of the BOX mets who is the resident WFO TC expert was talking about the reanalysis of big HUs that hit New England. And Sandy came up. He was asked if he thought it was still a TC at landfall, and he said, w/ his boss (MIC) on stage w/ him, "offline after a few beers, I say yes it was!"

Did I get @WxWatcher007 as pumped as @ineedsnow here? See what I am saying here? My "rants" are not w/o merit as to NHC not acknowledging legit TCs. The Jan 2023 event is perhaps the most glaring I have ever seen, and this is when they have long broaden the definition of a TC (2005 forced everyone too!) and declare them more. This is good as we are calling things for what they are, but still, you get odd stuff like this that gets ignored operationally. Yes, I know the Jan 2023 thing got included in post-season analysis, but that's not the point. Why was it not declared operationally? My guess is that they did not want to name something in Jan close the East Coast b/c the media would freak, and NHC would have been overrun w/ calls and inquires, so they just deferred to post-season analysis. Sorry, that isn't an excuse. It's your job to monitor and designate TCs in the Atlantic and EPAC in real-time. The atmosphere doesn't care what the calendar says or about our rules or policies, it does what it does! So you see my concern about this current storm and how it may evolve and what may or may not be done from authority. This ST or T evolution is not a low-prob or far-fetched scenario, whether you look at it from a meteorological objective or subjective POV!

10 to 50 times more likely than *what*? I see this often and there is no reference context and perspective given! Here's the problem w/ such stats. Atmospheric state variables (e.g. temp, vapor pressure, pressure, etc) are integrated into a highly complex, multi-variate, non-linear system. Axiomatically, meteorological variables exhibit non-Gaussian characteristics. That is, they don't follow a normal (Gaussian) distribution. “Unlikely events” like intense heatwaves, as it turns out, aren't as “unlikely” as it might seem in a non-Gaussian world. The wx in the real world doesn’t follow a Gaussian/normal distribution curve. Extreme events are far more common in a non-Gaussian distribution that reflects the physical world we live in. Bell curve graphs are an inappropriate use of statistics. Not only not Gaussian, but also the shape of the distribution changes w/ warming depending on location. So they apply stats/numbers that do not apply to reality (Gaussian vs non-Gaussian). When scientifically illiterate ppl try to normalize non-Gaussian disturbed data, you get the current nonsense. And we go back to the ever present issue, "how to lie w/ statistics" And while on the subject, concerning "sigma values" and those "1-in-a-million year events." Normalized anomalies used to be a good technique in meteorology to compare events by removing the mean and variance calculated from long-term gridded reanalysis data (30 yr), but now it's the hottest thing in climate activism. Normalized anomalies should not be interpreted as return periods in this way. The distribution of atmospheric variables, including 500 mb geopotential height, is not normal, and the climatology used for these normalized anomalies only contains 30 yr at each grid point w/ a 15-day centered mean and standard deviation. You can verify this by scanning the globe at any given time looking at this quantity. Say there is a Kona low at -5.5 sigma near HI for 500 heights. Obviously, that's not a 1-in-a-million yr event. 500 heights get extremely low in intense hurricanes in the tropics, and you'll see sigmas like -15. So that would mean a return rate longer than the Earth has existed. See how ridiculous this gets? But you get ppl parading these stats are as if they have any clue as to what they actually mean and how to apply them! Also, in reference to the above avg SSTs. You don''t need above avg SSTs to get an intense or record Nor'easter or any baroclinic storm. What matters most by far is baroclinicity in the atmosphere and jet structure. They have this vapid notion that things work linear 1-2-3 in the Earth's system, and *one* variable, like air temp or ocean temp, dictates everything else, and all else is trivial. And feedbacks are rife, furthering the complexity. An example of this is SSTs and TCs. All the increased SSTs in the world do not matter of the atmosphere does not cooperate, as in TPW values and wind shear. TC formation alone by far is dictated by atmospheric parameters, not ocean parameters. If SSTs were the biggest factor, we'd have far more TCs globally each year and they would not be confined to particular times of the year in each ocean basin.

Don't be too focused on the 26 C SST line. STS can occur w/ SSTs as low as 15 C, and the Jan 2023 event (a hurricane IMHO) formed a nice convective ring w/ a persistent eye over 21-23 C SSTs and retained this structure remarkably well to 40N, and still looked really good and tropical-like when it passed Sable Island where SSTs were 7 C. I posted the sat loop earlier, and you'll see what i mean. HU Alex in Jan 2016 way out in the Atlantic was like this, It actually look best when it accelerating N over cooler SSTs w/ a distinct eye!

This is fascinating evolution and not something that occurs that often. @CoastalWxneeds to broaden his wx horizons a bit, in addition to within 5 mi of Weymouth! Regardless of what the sfc low becomes, yes, it is irrelevant to the sensible wx impacts, unless it get "cute" and retains core TC characteristics as drifts near the S Coast!

Excellent point. I know of no sub-990 mb case in September for baroclinic deepening alone. Not that there has not been Nor'easters in Sep before, heck we get them in the summer sometimes, but the sfc low typically doesn't get too deep. 995-1000 usually is the limit. This event from July 22, 1983 stands out as one of the more impressive sfc lows for mid summer close to New England. 15z satellite image -- low was about 990 mb at this time.

@CoastalWx is by far lopsided and the fully versed weenie guru for winter wx. He's kinda weak in svr local storms and TCs! When we worked at WSI, he would always defer to me for those topics! And his typical reply after I would explain a situation? "WE'LL SEE!" LOL. The biggest contribution I recall I did for him that he has actually acknowledged? We we discussing the 6/1/11 TOR event and the problem/issues w/ the Springfield warnings, and I said to Scott, "no excuse to hesitate, this day was screaming big a classic spinner day for New England -- situational awareness is huge leading up to such an event!" And he liked the term "situation awareness!"

Wow, I had no idea there were STS in HURDAT2 that had winds in excess of 60 kt. Since NHC started declared ST systems regularly in the late 1990s, the has never been a "subtropical hurricane." The reasoning I heard is that if a ST system gets winds strong enough to reach hurricane-strength, it is can called fully tropical, which doesn't make any sense really. 65 kt is not some magic number that changes the structure of a storm. Many ET storms have sustained winds well over 65 kt, and there is nothing says they can't still have 65 kt when they go ST!

Concerning @CoastalWx's "garbage model" and how it handles TCs... Given the RRFS is new, I am not sure it handles TCs. I asked the modeling group if it handles TCs well. They said it should, but they said ti defer to the HAFS and the like. This event will be a good test at least when it comes to ET to ST/T transition. The RRFS is about 10 mb deeper than the other models, and shows a tight inner core pressure gradient eventually. That indicates tropical structure.