ATL: IOTA - Remnants - Discussion

[Hypercane_Kyle]

Lack of SFMR readings of 140 knots were the reason why Eta wasn't upgraded to Cat 5. Iota definitely appears to have become one per recon data.

I'm not sure what's more absurd, the fact we're looking at a Category 5 in November or the fact we're looking at Category 5 Hurricane Iota.

[kevin]

Recon dives back for a NE-SW pass. The next update in 10 minutes or otherwise the one afterwards in 20 minutes should have a new center pass.

[ElectricStorm]

Recon heading in for next pass

[Owasso]

Second pass incoming.

[aspen]

Lack of SFMR readings of 140 knots were the reason why Eta wasn't upgraded to Cat 5. Iota definitely appears to have become one per recon data.

I'm not sure what's more absurd, the fact we're looking at a Category 5 in November or the fact we're looking at Category 5 Hurricane Iota.

I think it’s just as or even more absurd that Hurricanes Eta and Iota in NOVEMBER both have strong arguments for peaking as a Cat 5.

[Hypercane_Kyle]

Pic for historical purposes.

[Kazmit]

Here comes the pass we all thought we were getting with Eta...

[CyclonicFury]

I suspect NHC is looking for a blend of 700 mb flight-level winds (at a 90% reduction) and SFMR wind data to blend to upgrade to Category 5. Right now the peak FL wind is 147 kt, and the peak SFMR wind is 140 kt. Blend the two and it averages out to 136.15 kt, which is closer to 135 kt than 140 kt (but actually converts to 156.5 mph, which would round up to 157 mph - the start of Category 5.)

Iota is extremely close to Category 5 (and IMO, it may have a better argument than Matthew or Lorenzo).

[kevin]

The two 'big ones' this season were both in November. This season has redefined the idea of the Atlantic late season, I never imagined something like this would be possible (not just Iota but all the late season activity this year).

[cycloneye]

 https://twitter.com/MikeAdcockWx/status/1328324875199639552

[kevin]

Looks like we have to wait for one more 10 minute update for the true center pass, 925.2 mbar but still 72 kt SFMR.

[Hypercane_Kyle]

NE quad looks like it's the weakest. That's consistent with what we saw last night.

[GCANE]

Looks like they couldn't launch a dropsonde on the first pass in the eye.
Apparently going for one now.

[supercane4867]

I suspect NHC is looking for a blend of 700 mb flight-level winds (at a 90% reduction) and SFMR wind data to blend to upgrade to Category 5. Right now the peak FL wind is 147 kt, and the peak SFMR wind is 140 kt. Blend the two and it averages out to 136.15 kt, which is closer to 135 kt than 140 kt (but actually converts to 156.5 mph, which would round up to 157 mph - the start of Category 5.)

Iota is extremely close to Category 5 (and IMO, it may have a better argument than Matthew or Lorenzo).

My question is that, if this is a CAT4 with 115kt SFMR and FL winds slightly lower than the CAT4 threshold the NHC would likely still upgrade it to a 4 as we saw in many cases historically. Why does the advancement from 4 to a 5 always get special treatment? It just seems nonsensical to me.

[ElectricStorm]

Final T is now at 7.0. Not seeing much that suggests it's not a Cat 5 at this point considering it's likely still strengthening

[GCANE]

Looks like eye maybe contracting on IR

[Hypercane_Kyle]

SFMR of 140 knots was what upgraded Matthew. If the NHC is to be consistent, then they should upgrade Iota IMO.

[GCANE]

First pass had 12nm wide eye.
Borderline pinhole

[Kazmit]

I suspect NHC is looking for a blend of 700 mb flight-level winds (at a 90% reduction) and SFMR wind data to blend to upgrade to Category 5. Right now the peak FL wind is 147 kt, and the peak SFMR wind is 140 kt. Blend the two and it averages out to 136.15 kt, which is closer to 135 kt than 140 kt (but actually converts to 156.5 mph, which would round up to 157 mph - the start of Category 5.)

Iota is extremely close to Category 5 (and IMO, it may have a better argument than Matthew or Lorenzo).

My question is that, if this is a CAT4 with 115kt SFMR and FL winds slightly lower than the CAT4 threshold the NHC would likely still upgrade it to a 4 as we saw in many cases historically. Why does the advancement from 4 to a 5 always get special treatment? It just seems nonsensical to me.

Yes, this has always annoyed me. NHC has no problem upgrading from cat 1 to cat 2, or cat 3 to cat 4, but the upgrade to a 5 seems to require so much more data and evidence. That's not how science is supposed to work.

[CyclonicFury]

I suspect NHC is looking for a blend of 700 mb flight-level winds (at a 90% reduction) and SFMR wind data to blend to upgrade to Category 5. Right now the peak FL wind is 147 kt, and the peak SFMR wind is 140 kt. Blend the two and it averages out to 136.15 kt, which is closer to 135 kt than 140 kt (but actually converts to 156.5 mph, which would round up to 157 mph - the start of Category 5.)
NHC has stated that the reliability of SFMR at extreme intensities is in question.
Iota is extremely close to Category 5 (and IMO, it may have a better argument than Matthew or Lorenzo).

My question is that, if this is a CAT4 with 115kt SFMR and FL winds slightly lower than the CAT4 threshold the NHC would likely still upgrade it to a 4 as we saw in many cases historically. Why does the advancement from 4 to a 5 always get special treatment? It just seems nonsensical to me.