WPAC: HECTOR - Post-Tropical

[Yellow Evan]

More ACE than forecast. I bet it's going to reach 40-45 before Saturday. I'm now doubting the intensity forecast. This was supposed to weaken to about a cat 2-3 by now but it's doing the practical opposite.

NHC has been hugging SHIPS/LGEM which is absolutely clueless with these types of systems. This should be a major for most of its lifetime in the CPAC, if not all of it.

[Eric Webb]

Hector is certainly in the ballpark of its theoretical MPI atm, don't see much reason why a small annular-ish TC with a well established inner core and light shear should struggle too much against dry/stable air, the slightly cooler SSTs south of Hawaii may put a modest cap on it but a major hurricane even there seems reasonable.

[1900hurricane]

I suspect guidance, both statistical and dynamical, may be potentially underdoing intensity due to the mid level dry air that exists across much of the Central Pacific. With Hector being a small system in a low shear environment (18Z SHIPS output showed basically negligible shear through tau 120), it may be more well shielded to dry air than normal. The same 18Z SHIPS output had mid level RH dropping below 40% at times, which will certainly make a difference in expected intensities. It's something to look out for at the very least.

[NotSparta]

"Satellite data indicate that the hurricane has continued to strengthen during the past 6 h, and the initial intensity has increased to at least 120 kt."
NHC essentially thinks Hector is no weaker than 120 KT, if Hector strengthens even a little could see them throw 125 KT at the next advisory.

Looking at the forecast, this thing could have ~35 ACE 2-3 days before it crosses the dateline, & that's if it weakens to 80kt as the forecast says. Hector has a pretty good chance at being the biggest ACE producer of 2018 so far

[Kingarabian]

Too bad this 2 hour old AMSR2 pass missed half the system. But from what I can see, there's a very intense eyewall present...

[Kingarabian]

[quote="Eric Webb"]Hector is certainly in the ballpark of its theoretical MPI atm, don't see much reason why a small annular-ish TC with a well established inner core and light shear should struggle too much against dry/stable air, the slightly cooler SSTs south of Hawaii may put a modest cap on it but a major hurricane even there seems reasonable.

[quote]

Those maps could also be conservative in regards to supported TC intensity.

Seeing some 28C popping up just east of the Big Island:

[xtyphooncyclonex]

"Satellite data indicate that the hurricane has continued to strengthen during the past 6 h, and the initial intensity has increased to at least 120 kt."
NHC essentially thinks Hector is no weaker than 120 KT, if Hector strengthens even a little could see them throw 125 KT at the next advisory.

Looking at the forecast, this thing could have ~35 ACE 2-3 days before it crosses the dateline, & that's if it weakens to 80kt as the forecast says. Hector has a pretty good chance at being the biggest ACE producer of 2018 so far

I'd argue it could be the biggest ACE producer of the EPAC & CPAC, not counting the West Pacific. Ioke did less than 40 before the cross to the IDL.... What's the record? (not counting the ACE after crossing)

[Kingarabian]

Trying to creep to T7.0...

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.0
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 05 AUG 2018 Time : 233000 UTC
Lat : 14:31:47 N Lon : 138:28:47 W


CI# /Pressure/ Vmax
6.5 / 936.6mb/127.0kt


Final T# Adj T# Raw T#
6.5 6.7 6.7

Estimated radius of max. wind based on IR : 18 km

Center Temp : +3.8C Cloud Region Temp : -71.3

[NotSparta]

I suspect guidance, both statistical and dynamical, may be potentially underdoing intensity due to the mid level dry air that exists across much of the Central Pacific. With Hector being a small system in a low shear environment (18Z SHIPS output showed basically negligible shear through tau 120), it may be more well shielded to dry air than normal. The same 18Z SHIPS output had mid level RH dropping below 40% at times, which will certainly make a difference in expected intensities. It's something to look out for at the very least.

[img]https://i.imgur.com/HHyHlIa.png[/ig]

As Eric Webb said above, an annular hurricane will have a less difficult time w/ the dry air. Could be significantly stronger than NHC forecast for 120 tau imo

[Kingarabian]

I suspect guidance, both statistical and dynamical, may be potentially underdoing intensity due to the mid level dry air that exists across much of the Central Pacific. With Hector being a small system in a low shear environment (18Z SHIPS output showed basically negligible shear through tau 120), it may be more well shielded to dry air than normal. The same 18Z SHIPS output had mid level RH dropping below 40% at times, which will certainly make a difference in expected intensities. It's something to look out for at the very least.

[img]https://i.imgur.com/HHyHlIa.png[/ig]

As Eric Webb said above, an annular hurricane will have a less difficult time w/ the dry air. Could be significantly stronger than NHC forecast for 120 tau imo

I doubt dry air will affect it as much since it's practically annular, but at these intensities (close to cat.5), conditions need to be pristine to maintain them.

[Ntxw]

I suspect he is deserving of honorable mention in "Top hurricane sat photos of all time..." thread.

[Kingarabian]

[img]http://i68.tinypic.com/16bzr4o.png[img]

Who knows really, but this is close to a cat.5 or probably is one. Very very impressive presentation, the best we've seen in the EPAC for a long while.

[CrazyC83]

With the new data, I would estimate the intensity at 130 kt. The T6.7 estimate seems fairly reasonable.

[Eric Webb]

I'm certainly very excited to see what the Hurricane Hunter plane will find with Hector tomorrow, wouldn't be surprised if they discovered anything from a mid grade category 3 to a category 5 hurricane, a 15-20 KT error in satellite intensity estimates is pretty standard.

[1900hurricane]

"Satellite data indicate that the hurricane has continued to strengthen during the past 6 h, and the initial intensity has increased to at least 120 kt."
NHC essentially thinks Hector is no weaker than 120 KT, if Hector strengthens even a little could see them throw 125 KT at the next advisory.

Looking at the forecast, this thing could have ~35 ACE 2-3 days before it crosses the dateline, & that's if it weakens to 80kt as the forecast says. Hector has a pretty good chance at being the biggest ACE producer of 2018 so far

I'd argue it could be the biggest ACE producer of the EPAC & CPAC, not counting the West Pacific. Ioke did less than 40 before the cross to the IDL.... What's the record? (not counting the ACE after crossing)

John '94 technically holds the record for Pacific ACE east of the International Date Line with 53.9775 units, but there is a catch with that number. John crossed the International Date Line and then returned. 51.08 of it was accrued prior to the first cross, which actually isn't the most in one consecutive stint. That goes to Kevin '91, which accumulated 52.1425 units over the course of its life.

[Dylan]

 https://twitter.com/DylanFedericoWx/status/1026266374262476801

[Kingarabian]

SAB kept it at 6.0.

Have to keep a close eye on the track now to see how well Hector is following it:

[xtyphooncyclonex]

I suspect he is deserving of honorable mention in "Top hurricane sat photos of all time..." thread.

"Well, so much for the shear."

[CrazyC83]

Hector is certainly in the ballpark of its theoretical MPI atm, don't see much reason why a small annular-ish TC with a well established inner core and light shear should struggle too much against dry/stable air, the slightly cooler SSTs south of Hawaii may put a modest cap on it but a major hurricane even there seems reasonable.
Seeing some 28C popping up just east of the Big Island:

That's a real breeding ground for intensification if Hector stays low and gets into that 30, 31C water closer to the dateline. That could EASILY support a strong cat 5.

[Kingarabian]

A few SSMIS passes will be in soon. Hope they don't miss the core.