ATL: IOTA - Remnants - Discussion

[aspen]

Wow, MPI in the Caribbean is insanely high at the moment, even better than it was during Delta or Eta if I recall correctly. Whatever happens to 98L, it's not gonna be the MPI that will limit this system.

https://i.imgur.com/ExxppBz.png

I thought Eta was 2020’s last hurrah. I guess that might be Iota...unless another Caribbean monster is in store for the end of the month. Imagine a Caribbean major that lasts into December.

With the exception of the CMC, which is the fastest model (landfall in 120 hours), all of the globals have a landfall at 144 hours or later, and development within 3 days. That’ll be anywhere from 2 to 4 days for Iota to build a core and intensify, and if SSTs/MPIs are really going to be that high, we could be looking at another Eta — a high end Cat 4 or a Cat 5 with insanely deep convection due to the cool tropopause. Praying that recon won’t be problematic this time.

[Iceresistance]

Like, how strong is 98L expected?

[aspen]

Like, how strong is 98L expected?

Too early to tell, but based on the model tracks and intensity, the trend of Caribbean systems this year, and the very high SSTs/MPIs, I’d say 98L/Iota has a good shot of becoming yet another major.

[underthwx]

98L has been eating it's Wheaties.... Looks very healthy this morning...

[Iceresistance]

Like, how strong is 98L expected?

Too early to tell, but based on the model tracks and intensity, the trend of Caribbean systems this year, and the very high SSTs/MPIs, I’d say 98L/Iota has a good shot of becoming yet another major.

Not just that, Eta's cold water trail does not exist!

[Iceresistance]

Near the center, heading to the left is 98L

[AutoPenalti]

It's still early but based on the 500mb heights, the GOM and SE US are closed for the season. Unfortunately, the same can't be said about CA.

[Iceresistance]

98L has imporved over the last 12 hours

[underthwx]

98L has imporved over the last 12 hours

Definitely...

[aspen]

There are currently three potential tracks once 98L/Iota reaches roughly ~77W: either it continues SW into Costa Rica/southern Nicaragua (Euro, CMC, GFS-Para), goes a little north but is blocked into Nicaragua/Honduras just like Eta (GFS), or it gets north of Honduras before being blocked south (ICON). Despite these varying tracks, they're generally consistent with timing, with all but the CMC showing a landfall sometime a little after 144 hours out, although some are later than others.


SSTs are at least 28.5C across 98L/Iota's potential tracks, with the highest SSTs and maximum potential intensities in the SW Caribbean. Assuming these MPIs hold up, they'll be higher than when Eta was in this region, meaning Iota has the potential to become another sub-925 mbar Cat 4/5 -- assuming other aspects (wind shear, outflow channels, atmospheric moisture, core structure) support it. It seems to be that Iota will be 2020's last shot to produce a Category 5 (which is the exact same thing I said about Delta...then Zeta...then Eta).

[us89]

12z GFS has a very Eta-like track. Relatively quick westward motion followed by a big slowdown, intensification, and dive southward very close to the CA coast, then finally moving ashore in Nicaragua. Pressure bottoms out at 978 mb on this run, but the 06z had pressures in the 960s. Will certainly be one to watch.

[Iceresistance]

The upper end of the convection in 98L is showing signs of spinning, it's noticeable here on a 12 hour loop on Windy.com: https://www.windy.com/-Satellite-satellite?satellite,17.879,-66.796,6

[Iceresistance]

There are currently three potential tracks once 98L/Iota reaches roughly ~77W: either it continues SW into Costa Rica/southern Nicaragua (Euro, CMC, GFS-Para), goes a little north but is blocked into Nicaragua/Honduras just like Eta (GFS), or it gets north of Honduras before being blocked south (ICON). Despite these varying tracks, they're generally consistent with timing, with all but the CMC showing a landfall sometime a little after 144 hours out, although some are later than others.
https://i.imgur.com/YBWRg3H.png

SSTs are at least 28.5C across 98L/Iota's potential tracks, with the highest SSTs and maximum potential intensities in the SW Caribbean. Assuming these MPIs hold up, they'll be higher than when Eta was in this region, meaning Iota has the potential to become another sub-925 mbar Cat 4/5 -- assuming other aspects (wind shear, outflow channels, atmospheric moisture, core structure) support it. It seems to be that Iota will be 2020's last shot to produce a Category 5 (which is the exact same thing I said about Delta...then Zeta...then Eta).
https://i.imgur.com/MnSbOsi.png

(On the Bottom Photo)
Look closer at the potental lowest pressure down to 880

[aspen]

There are currently three potential tracks once 98L/Iota reaches roughly ~77W: either it continues SW into Costa Rica/southern Nicaragua (Euro, CMC, GFS-Para), goes a little north but is blocked into Nicaragua/Honduras just like Eta (GFS), or it gets north of Honduras before being blocked south (ICON). Despite these varying tracks, they're generally consistent with timing, with all but the CMC showing a landfall sometime a little after 144 hours out, although some are later than others.
https://i.imgur.com/YBWRg3H.png

SSTs are at least 28.5C across 98L/Iota's potential tracks, with the highest SSTs and maximum potential intensities in the SW Caribbean. Assuming these MPIs hold up, they'll be higher than when Eta was in this region, meaning Iota has the potential to become another sub-925 mbar Cat 4/5 -- assuming other aspects (wind shear, outflow channels, atmospheric moisture, core structure) support it. It seems to be that Iota will be 2020's last shot to produce a Category 5 (which is the exact same thing I said about Delta...then Zeta...then Eta).
https://i.imgur.com/MnSbOsi.png

(On the Bottom Photo)
Look closer at the potental lowest pressure down to 880

Correct, but remember, this is maximum *potential* intensity. Storms usually don’t reach the lowest pressure on this chart. For example, Dorian bottomed out at 910 mbar in a region that could also support down to 880-890 mbar.

[Iceresistance]

There are currently three potential tracks once 98L/Iota reaches roughly ~77W: either it continues SW into Costa Rica/southern Nicaragua (Euro, CMC, GFS-Para), goes a little north but is blocked into Nicaragua/Honduras just like Eta (GFS), or it gets north of Honduras before being blocked south (ICON). Despite these varying tracks, they're generally consistent with timing, with all but the CMC showing a landfall sometime a little after 144 hours out, although some are later than others.
https://i.imgur.com/YBWRg3H.png

SSTs are at least 28.5C across 98L/Iota's potential tracks, with the highest SSTs and maximum potential intensities in the SW Caribbean. Assuming these MPIs hold up, they'll be higher than when Eta was in this region, meaning Iota has the potential to become another sub-925 mbar Cat 4/5 -- assuming other aspects (wind shear, outflow channels, atmospheric moisture, core structure) support it. It seems to be that Iota will be 2020's last shot to produce a Category 5 (which is the exact same thing I said about Delta...then Zeta...then Eta).
https://i.imgur.com/MnSbOsi.png

(On the Bottom Photo)
Look closer at the potental lowest pressure down to 880

Correct, but remember, this is maximum *potential* intensity. Storms usually don’t reach the lowest pressure on this chart. For example, Dorian bottomed out at 910 mbar in a region that could also support down to 880-890 mbar.

Dorian had issues with dry air, wind shear, & upwelling.

The max intensity is only possible under perfect conditions, Cyclone Winston achieved the lowest potental pressure of 884 MB over Fiji in 2016.

[ElectricStorm]

(On the Bottom Photo)
Look closer at the potental lowest pressure down to 880

Correct, but remember, this is maximum *potential* intensity. Storms usually don’t reach the lowest pressure on this chart. For example, Dorian bottomed out at 910 mbar in a region that could also support down to 880-890 mbar.

Dorian had issues with dry air, wind shear, & upwelling.

The max intensity is only possible under perfect conditions, Cyclone Winston achieved the lowest potental pressure of 884 MB over Fiji in 2016.

I mean... Dorian had 185 mph winds. There have been storms with those winds with pressures in the 880s and 890s. So in terms of winds Dorian pretty much got to the max before landfall

[Iceresistance]

Dry air is nonexistant on where 98L is going to


Heat potental is still higher


Wind shear is extremely low.

[ElectricStorm]

I hate to say it but early indications are that this is going to be the next big one this year... Maybe this will FINALLY be the last one of the season...

[aspen]

Correct, but remember, this is maximum *potential* intensity. Storms usually don’t reach the lowest pressure on this chart. For example, Dorian bottomed out at 910 mbar in a region that could also support down to 880-890 mbar.

Dorian had issues with dry air, wind shear, & upwelling.

The max intensity is only possible under perfect conditions, Cyclone Winston achieved the lowest potental pressure of 884 MB over Fiji in 2016.

I mean... Dorian had 185 mph winds. There have been storms with those winds with pressures in the 880s and 890s. So in terms of winds Dorian pretty much got to the max before landfall

Yeah it reached MPI in terms of winds...perhaps it even exceeded it. I’m not quite sure why the pressure was so high for a 160 kt storm (not that it was high in general; recon found extrapolated pressures down to 909 mbar).

When it comes to the MPI chart, I like to add 10-25 mbar to even MPI pressure for a more likely maximum intensity under more probably good conditions — not perfect, but pretty good. So in that 880-890 mbar zone, perhaps Iota could get down to 900-920 mbar.

[Iceresistance]

And there is one troublesome issue with 2020


Pinhole eyes