Arabian Sea: CHAPALA - Post-Tropical

[Kingarabian]

From Dr. Masters blog:

[Alyono]

shift those totals WELL west. HWRF has an unrealistic track

[Alyono]

eyewall replacement underway

Hopefully it struggles from here on.

it should regain if not exceed its old intensity

[Yellow Evan]

eyewall replacement underway

Hopefully it struggles from here on.

it should regain if not exceed its old intensity

Depends on how much dry air is a factor. It's been a messy ERC so far so I won't be shocked if we end up with a 60 mile wide eye.

[mrbagyo]

Shear is relaxing along its path, if thats the case, it might not choke up a lot of dry air into its core. Let's see. ..

[Alyono]

there is one other possibility. That is this drops far enough south that it runs over Somalia. Not impossible, but not the most likely solution

[wxman57]

I'm not sure it's an ERC. Microwave does show the eye collapsing but I don't see another eyewall building. It's definitely a good bit weaker than 12 hours ago, possibly due to dry air entrainment from the northwest. I don't think it will recover to its former intensity.

http://tropic.ssec.wisc.edu/real-time/mimic-tc/2015_04A/webManager/last24hrs.gif

[WeatherGuesser]

First stories starting to appear:

Rare cyclone heads toward Arabia, may dump year's worth of rain
USA TODAY - ‎6 hours ago‎


Cyclone Chapala is taking aim at the Arabian Peninsula and is forecast to strengthen into a Category 5 storm today, with winds of up to 166 mph. It should approach Oman and Yemen at Category 2 or 3 strength late Sunday or early Monday.

[WeatherGuesser]

NASA satellites have been providing data on powerful Tropical Cyclone Chapala as it continued strengthening in the Arabian Sea. The Global Precipitation Measurement Mission or GPM core satellite provided a look at strengthening Tropical Cyclone Chapala in the Arabian Sea. Additionally, NASA's Aqua satellite got a good look at the storm's small eye.

Tropical Cyclone Chapala developed in the very warm waters of the Arabian Sea west of India on October 28, 2015. Tropical Cyclone Chapala is a Category 4 Hurricane on the Saffir-Simpson Scale and is forecast to become a Category 5 later on October 30, 2015.

http://phys.org/news/2015-10-nasa-power ... nfall.html

[WeatherGuesser]

MODIS Rapid Response:




http://lance-modis.eosdis.nasa.gov/cgi- ... 3.0950.jpg

[Kingarabian]

A powerful hurricane bearing down on a desert...

Hard to wrap your head around this one.

[wxman57]

Dvorak down to 5.0. Probably a Cat 2 now.

[Yellow Evan]

Looking quite ragged, but I imagine the RMW has expanded quite a bit. While I'd say this is around 105 knots (an an ugly 105 knots at that) now, this is still a very dangerous hurricane to a region where tropical cyclones are quite rare.

FYI, this isn't the only area where TC's hit that is a Desert. Western Australia and the Baja California Peninsula are the same way.

[TropicalAnalystwx13]

A recent microwave pass confirms Chapala underwent an eyewall replacement cycle earlier today.

It's a tough call whether we see any strengthening over the next day or two. Shear remains low and ocean temps remain warm, but there is an excess amount of dry air nearby. That said, Chapala did a good job of keeping dry air out of its core prior to the EWRC.

[Kingarabian]

Looks like we'll be seeing a 30-40NM eye if it manages to complete the cycle.

[1900hurricane]

Looks like we'll be seeing a 30-40NM eye if it manages to complete the cycle.

It'll probably continue to contract as the inner eyewall dissipates. Looks like a pretty standard eyewall replacement cycle, and we'll probably get a common eye size out of it.

I'm actually pretty impressed it's managed to keep the dry air out while the eyewall replacement cycle has been ongoing. A few prior microwave passes made look like it was starting to get a wrap in, but the pass Cody posted above looks pretty clean. At this point, I'd say I'm in the restrengthening camp with Alyono, although probably not as agressive as him (low to mid-grade cat 4 following eyewall replacement seems good to me).

[wxmann_91]

From that MW it looks like southerly shear rather than an ERC that is causing the weakening. Given the small size of Chapala and the vastness of the surrounding dry air, even the slightest shear (10 kt or so) would cause weakening.

[Kingarabian]

[Yellow Evan]

ERC looks recoverable, but the CDO needs to smooth out, as it's gotten really ragged. I'd say this is around 95 knots now.

[NotoSans]

Seems to have completed the ERC.