EPAC: CRISTINA - Post-Tropical

[1900hurricane]

TAFB is back down to 3.5/4.0 (their FT was 4.0 at 12Z). I'm skeptical the CI gets it done with a lower FT, but we'll see.

EP, 05, 202007110000, 10, DVTS, CI, , 2000N, 11630W, , 2, 65, 2, 987, 2, DVRK, , , , , , , , , , , , , , E, TAFB, SK, VI, 3, 3540 /////, , , GOES17, CSC, T,

[Hammy]

Still 60 kt....

Time to riot?

NHC seems very conservative with Pacific upgrades and intensity estimates--I feel like this would've already been a hurricane were it in the Atlantic.

[aspen]

It’s had an eye for at least the last 18 hours, what more do they want?

[ScottNAtlanta]

Cristina seems to be making one last push for hurricane strength. I'd probably estimate the intensity at 65 kt considering the dry slot surrounded by a ring of at least -40C cloud tops, with cloud tops near -70C in the southern semicircle.

I'm pretty sure that's an eye not a dry slot. It was a nearly perfect cloud free ring sorrounded by a weak eyewall.

Not only that, but since I last commented this afternoon the eye (and yes it is an eye) has contracted and the tops are noticeably cooler. I am 100% in the Hurricane camp. Looking at visible it plainly obvious. You dont need recon for that

[ScottNAtlanta]

[StruThiO]

They'll probably readjust the intensity in post-analysis?

[1900hurricane]

I'd give it to it at this point.

[AxaltaRacing24]

clearly a 70 mph tropical storm

[cycloneye]

Advisory not out after 8 PM PDT 11 PM EDT? Maybe a tech issue?

[1900hurricane]

Maybe they're debating the intensity amongst themselves.

[Hammy]

This is the latest past the advisory time that I can remember going without an update.

[cycloneye]

Here it is. He says, "can not rule out"

Tropical Storm Cristina Discussion Number 18
NWS National Hurricane Center Miami FL EP052020
500 PM HST Fri Jul 10 2020

Cristina's appearance suggests that the system has gotten better
organized over relatively cold waters than it ever did over warmer
waters to the south. The cyclone has a banding eye-like feature, and
cold cloud tops associated with deep convection have recently come
close to wrapping all the way around the cyclone's center. Although
subjective Dvorak intensity estimates at 00Z could justify calling
Cristina a hurricane, the most recent UW-CIMSS SATCON is 55 kt, and
ASCAT data valid around 18Z had max winds of only 45 kt. The initial
intensity is therefore held at 60 kt as a compromise of the various
estimates.

Cristina is forecast to be over 24 deg C waters in about 12 h and it
would be surprising if it strengthened overnight. That said, given
its current satellite appearance and otherwise favorable surrounding
environment, I can not rule out the possibility that Cristina could
briefly become a hurricane during the next few hours. In general,
the NHC intensity forecast has not been substantially changed, and
Cristina is forecast to gradually weaken for the next few days.
Various dynamical models indicate that the tropical storm will
maintain some deep convection for another couple days, and then
become a post-tropical remnant low early next week.

The tropical storm is forecast to continue moving steadily westward
to west-northwestward for the next two to three days, steered by a
mid-level ridge extending across most of the eastern North Pacific.
After that time, the shallow remnant low should continue generally
westward, steered by low-level easterly flow. The models are in
fairly good agreement, and the NHC track forecast is on top of the
multi-model consensus near the middle of the guidance envelope.


FORECAST POSITIONS AND MAX WINDS

INIT 11/0300Z 20.1N 116.8W 60 KT 70 MPH
12H 11/1200Z 20.5N 118.9W 60 KT 70 MPH
24H 12/0000Z 21.0N 121.4W 50 KT 60 MPH
36H 12/1200Z 21.3N 124.0W 45 KT 50 MPH
48H 13/0000Z 21.7N 126.4W 40 KT 45 MPH
60H 13/1200Z 22.0N 128.8W 35 KT 40 MPH
72H 14/0000Z 22.6N 131.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 15/0000Z 23.5N 136.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 16/0000Z 24.0N 141.5W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Zelinsky

[CyclonicFury]

A bit surprising they based the 60 kt intensity on a 9-hour old ASCAT pass and the 55 kt SATCON estimate, which is weighed heavily down by an erroneously low 32-knot ADT value.

[Yellow Evan]

ASCAT should have been tossed IMO.

[StruThiO]

Idk bit of a headscratcher

[1900hurricane]

Looks like they're already throwing ADT, but it's also dragging SATCON way down. Every microwave estimate is above the SATCON mean, but ADT is just being an absolute boat anchor. It honestly also probably needs to be tossed considering this mentioned disparity between members.



45 kt (23 m/s) ASCAT wind vectors actually correlate better to 60 kt (30 m/s) winds from dropsonde data according to a study from Chou, Wu, & Lin. I don't think it's too far-fetched for it to have intensified 5 kt more over the subsequent 9 hr.

[cycloneye]

After this, IMO, it will be upgraded on post season analysis.

[Chris90]

The Cristina Controversy of 2020 continues.

I'd give it 65kts at least at this point. The eye has seemed to tighten up a bit, which is a good indicator the pressure has probably dropped a few mbs and the gradient has probably tightened a bit too.

It's strange that while in really good conditions Cristina struggled, but when she got farther north with cooling waters and less heat content she started to get her act together.

Slightly off topic, but does anyone know of any research comparing the coupling between ocean and atmosphere in the EPAC compared to other basins around the world? Storms in this basin seem to be able to ride the 26C isotherm and maintain intensity or slightly intensify better than any other basin. They take on an annular-esque structure with larger, more stable eyes and less banding in this basin much more frequently than any other in my opinion.

[Kingarabian]

It's so odd. The NHC usually does very well in these situations.

[Kingarabian]

The Cristina Controversy of 2020 continues.

I'd give it 65kts at least at this point. The eye has seemed to tighten up a bit, which is a good indicator the pressure has probably dropped a few mbs and the gradient has probably tightened a bit too.

It's strange that while in really good conditions Cristina struggled, but when she got farther north with cooling waters and less heat content she started to get her act together.

Slightly off topic, but does anyone know of any research comparing the coupling between ocean and atmosphere in the EPAC compared to other basins around the world? Storms in this basin seem to be able to ride the 26C isotherm and maintain intensity or slightly intensity better than any other basin. They take on an annular-esque structure with larger, more stable eyes and less banding in this basin much more frequently than any other in my opinion.

It's odd but yeah the EPACs storms are considerably more resilient for some reason. Daniel 2006 seemed to have started this all.