James Franklin

I know there are a lot of misuses of the SSHWS, but I find it tremendously helpful for our own preparation. We don't live in a surge zone, so our go/no-go decision purely follows the wind threat. If the core of a forecast 4 or 5 is coming, based on the track, we go. C3 or less, we stay.

As for a SSHWS Category 6, my earlier comment was that I viewed it as a marketing gimmick (for climate change). In real time, I don't see how a 6 helps anyone prepare, and potentially hinders responses to the now lower categories.

I was trying to argue that the SSHWS could be used to provoke a response to the wind hazard as hurricanes approach, while the EF scale had no real-time function (being assigned only afterwards). (½)

I imagine that’s part of it, but as far as I know they were developed completely independently. Also, dividing up the range of possible hurricane 1-min winds and the range of tornadic gusts into 5 bins each is bound to yield different thresholds.

I’m thinking they manage to lose five of the next four.

Another difference is that the SSHWS is a preparedness tool, in that it’s a shorthand for the upcoming wind threat. EF serves no real time function since it’s only quantified after the event.

Same old story with the Canes. Now let’s see if the Panthers can salvage something of this so-far crappy day.

So many damn penalties.

They keep trying that play. I don’t think it works as well as they think it works. (Done in Princess Bride accent.)

Not sure I follow. SSHWS is based on 1-min mean winds and only estimates potential damage. (Actual damage not required.) EF scale, on the other hand, is a damage scale that only estimates winds (in the form of gusts). So they’re different in both purpose and duration of the winds involved.

Not in the public ATCF decks in real time. Added after the season is done.

Michael, it's questions like this that make me wish I was still getting paid to do stuff like this. ;-)

I'll take a look and report back.

And a puzzler - why is the GFS deterministic run so much worse than the GFS ensemble mean (AEMI)? I don't think I'm used to seeing that kind of discrepancy.

Another thing that's gratifying to me is to see HCCA (the corrected consensus based on past model trends) beating IVCN and TVCN. I worked on the fringes of that effort for many years and pleased to see HCCA adding value. HFIP supported that work.

Made a point of that in my just-posted combo verification of AL/EP. I don't see the EMXI but I'm sure you have. How's it doing for track this year?

Here are updated verifications for 2025, AL/EP combined, EMXI not available. Impressed that NHC is beating everything, including consensus, for intensity, and everything but Google DeepMind (GDMI) for track. Rough year for GFS and the statistical intensity aids. Banner year for GDMI.

A team that’s built with a small number of stars and a wealth of complementary pieces is going to struggle without the stars. Without 16 and 19 on the forecheck they don’t generate enough pressure or turnovers. Gonna be a struggle to make the playoffs.

Haven’t watched the Dolphins in weeks. Why did I decide to put myself through this again tonight?

If you’re going to show OFCI, it should be from the same cycle as all the other “I” models. However, I think it’ll be confusing to users which is why I suggested leaving it out.

I second Philippe's comment. Apples to Apples comparison is to show OFCL against all the other "I"models, as that grouping is all based on the same synoptic suite of guidance. OFCI really isn't guidance at all but just a reference for the forecaster to help assess continuity, and could be omitted.

Found an old email thread from my archives. A number of us looked at it in 2006 and concluded it was likely false. That agrees with my assessment now. The Katrina peak isn't valid.

I thought the AI response was on the mark, except maybe the part about 20 samples near the beginning - I no longer remember exactly how the filter is coded. The 3-bullet summary you have here seems good to me.

Thanks for that legwork! The sounding has lots of dropouts and there appear to be instability issues associated with the number of GPS satellites, but obviously the data were transmitted in real time. They look suspicious to me on an initial pass but I'm still digging into it.

Hopefully I can find the raw file. It was obviously of interest at the time and so must be in the archive.

Not quite. The processing code has an almost 30-year history through three main developers, of which I was the first, but believe it’s still a low-pass filter with a half-power amplitude set at any desired wavelength - in this case 5 s. Near endpoints filtering tapers to zero.

I’m sure I’ve worked that sonde up before, but after 20 years I just don’t remember.

The raw wind data are taken every 0.25 s. Before transmission they’re run through a filter with a 5-s wavelength. Until a couple years ago it was a 10-s filter.

That Katrina wind certainly looks strange. I might have the raw sonde data in an archive, or can pull it from HRD’s archive. I’ll look tomorrow.

The sequence of NHC forecasts verifying at 28/18Z, roughly the time of landfall, is quite remarkable given the spread of the guidance and the track turns involved. Five days worth of OFCLs consistently focused on the western ⅔ of Jamaica, and with remarkable steadiness in timing. Nicely done NHC!

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