ATL: HUMBERTO - Post-Tropical - Discussion

[plasticup]

Holy cow that is an eye! What a huge one! If it gets any wider we may get a brush from that eyewall

[wx98]

Pressure has leveled off in the low 950s as of now. Not a surprise since it has been undergoing an EWRC. Can’t rule out some deepening, but I would expect gradual weakening from here...

[plasticup]

Temps dropping in the northern eyewall. If that wraps around we could see some strengthening. The shear keeps pressuring the eye though (more obvious on visible imaging)

[NDG]

Recon confirms that Humberto is still a MH. Strongest winds in SE quadrant.

133200 3129N 06749W 6974 02893 9734 +127 +037 229111 113 095 000 00
133230 3128N 06747W 6970 02903 9752 +119 +035 230111 112 095 000 00
133300 3127N 06746W 6967 02918 9767 +115 +037 228112 113 095 000 00
133330 3126N 06745W 6970 02925 9782 +112 +036 227114 114 097 000 00
133400 3125N 06743W 6963 02940 9794 +107 +033 228112 114 097 000 00
133430 3125N 06743W 6963 02940 9824 +089 +037 229107 111 097 000 00
133500 3122N 06741W 6970 02948 9844 +079 +041 229113 116 090 004 00
133530 3121N 06739W 6968 02962 9860 +074 +044 229118 120 083 006 00

[1900hurricane]

Latest pass:

[NDG]

Very good chance that Bermuda will feel at least Cat 2 force winds if Humberto keeps its current heading, and those Cat 2 winds extend far away from its eye on the SE quadrant which will be going over the Island.

[Kazmit]

It has been eerily calm this morning with some showers and light winds. Wind and rain starting to pick up a bit now, I think conditions will deteriorate rapidly within the next few hours.

[plasticup]

That recent squall looks like it will be the last until the real deal arrives. Wish we had more up to date recon because the satellite presentation has changed so much. Looks to me like a wider wind field.

[SconnieCane]

Hot towers keep firing on the NW side of the eyewall, getting pulled around, weakening, and then more fire up, but there's something keeping it from establishing a fully closed eyewall for very long. Probably good enough to maintain something in the 95-105kt intensity range but not much more than that.

I wonder if based on Humberto's size and direction of approach/passage, surge might be a serious problem for the southern/western coasts on Bermuda? How surge-prone are those coasts?

[plasticup]

How surge-prone are those coasts?

Not at all. Good elevation along the whole coastline. The causeway may flood, but it will be closed long before then.

[SconnieCane]

How surge-prone are those coasts?

Not at all. Good elevation along the whole coastline. The causeway may flood, but it will be closed long before then.

Well, that's fortunate because Humberto has the classic structure of a storm that pushes a huge amount of water to the right of its track and this direction of approach seems kind of unusual since Humberto is rather far south to be moving almost due east.

[Kazmit]

Wow, the latest advisory expanded the hurricane-force wind field to 105 miles. Since it is expected to pass around 85 miles from Bermuda, we should definitely receive hurricane force winds for a little bit. Believe it or not, the sun is still shining here and winds are below 20mph.

[wx98]

Recon passing through the W/NW eyewall finding FL ad SFMR around 100 kt
They got the intensity from the previous pass which showed 115-120 kt FL to the SE of the eye

[DioBrando]

New advisory calls for 120mph

Oofy uwu

[1900hurricane]

I'm ok with the 105 kt, but I probably would have kept 100 kt. The upgrade was probably a SFMR/flight level blend with maybe a slight emphasis towards flight level. Nothing wrong with that line of thought, but dropsonde observations suggested the highest winds (peak 120 kt at flight level on second pass) weren't mixing down to the surface quite as efficiently as usual. I probably would have favored the slightly lower SFMR a little more (peak 101 kt on last pass). Standard 0.9 reduction of 120 kt 700 mb winds is 108 kt, but a 0.85 reduction is 102 kt, which matches SFMR pretty well. Not a huge difference, and really probably me just splitting hairs.

[plasticup]

Eye visible on Bermuda radar: http://www.weather.bm/tools/graphics.as ... 0PPI&user=

Looks about 100 km across.

[Buck]

...TROPICAL-STORM-FORCE WIND GUSTS OCCURRING ON BERMUDA... ...HURRICANE-FORCE WINDS EXPECTED ON THE ISLAND BY THIS EVENING...

2:00 PM AST Wed Sep 18
Location: 32.4°N 67.2°W
Moving: ENE at 16 mph
Min pressure: 952 mb
Max sustained: 120 mph

[sikkar]

Bermuda live cam
https://www.earthcam.com/world/bermuda/ ... am=bermuda

[Kazmit]

It's really starting to blow now. I think it will pass a little closer than expected.

[sikkar]

That EWRC brought the right eyewall closer to you, although it looks weak on radar but still intense conditions on the ground.