ATL: IRMA - Post-Tropical - Discussion

[shawn6304]

NHC has been using the Fl straights as a holding cell for Irma the last 3 advisories at 120hr. I would think they have to shift NE on next to show the turn into FL. Especially with the GFS well east.

its one run of the gfs, i doubt they bend it that hard to make landfall on the peninsula...if the euro shows an east trend then yes at 5 pm they will bend it

Hello ,

I am confused by this post, hasn't the GFS shown a peninsula hit the last 5 or 6 runs? sorry if i missed something i am trying to keep up

[AJC3]

WTNT61 KNHC 051147
TCUAT1

Hurricane Irma Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL112017
745 AM AST Tue Sep 05 2017

...HURRICANE IRMA BECOMES A CATEGORY 5 ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE...

NOAA and Air Force hurricane hunter aircraft data indicate Hurricane
Irma has intensified into an extremely dangerous Category 5
hurricane on the Saffir-Simpson Hurricane Wind Scale with maximum
winds of 175 mph (280 km/h) with higher gusts. A special advisory
will be issued at 800 AM AST (1200 UTC) in lieu of the scheduled
intermediate advisory for Irma.


SUMMARY OF 745 AM AST...1145 UTC...INFORMATION
----------------------------------------------
LOCATION...16.7N 57.7W
ABOUT 270 MI...440 KM E OF ANTIGUA
ABOUT 280 MI...445 KM ESE OF BARBUDA
MAXIMUM SUSTAINED WINDS...175 MPH...280 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...929 MB...27.44 INCHES

$$
Forecaster Brown/Landsea

[bg1]

Air Force just measured 158-kt flight-level and 154-kt SFMR in NE eyewall. This is well above threshold for cat 5. Horrible.

Yipes
The FL winds seem low given the SFMR, or is this a feature of intense storms?

[Evil Jeremy]

Special advisory indeed on the way

[Kingarabian]

Those wind numbers makes Irma the strongest Cyclone in 2017 on earth

If those sub 900 pressures from the GFS verify, how high will Irma's winds be? 200mph plus?

[Kazmit]

So terrifying...

[tolakram]

11:38z

[xtyphooncyclonex]

NOAA says 171 kt max-flight level on VDM.... Considering Air Force SFMR of 154 kt, this is probably a 155 kt hurricane. Incredible.

000
URNT12 KWBC 051129
VORTEX DATA MESSAGE AL112017
A. 05/11:10:54Z
B. 16 deg 42 min N
057 deg 41 min W
C. NA
D. 110 kt
E. 188 deg 12 nm
F. 297 deg 120 kt
G. 189 deg 17 nm
H. 930 mb
I. 14 C / 2453 m
J. 21 C / 2412 m
K. 16 C / NA
L. CLOSED
M. C23
N. 12345 / NA
O. 0.1 / 1 nm
P. NOAA2 0711A IRMA OB 10
MAX OUTBOUND FL WIND AND MAX FL WIND 171 KT 024 / 19 NM 11:16:47Z
MAX FL TEMP 21 C 012 / 6 NM FROM FL CNTR
CNTR DROPSONDE SFC WIND 265 / 10 KTS

Oh my God. How astonishing. Didn't expect this at all, hoping everyone throughout the Northern Antilles is safe and well-informed about the forecoming threat.

Pressure relatively high at 930 mb.

[GCANE]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 5th day of the month at 11:45Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF99-5309
Storm Number & Year: 11 in 2017
Storm Name: Irma (flight in the North Atlantic basin)
Mission Number: 8
Observation Number: 04 ( See all messages of this type for this mission. )
A. Time of Center Fix: 5th day of the month at 11:19:10Z
B. Center Fix Coordinates: 16°40'N 57°42'W (16.6667N 57.7W)
B. Center Fix Location: 262 statute miles (422 km) to the ENE (69°) from Roseau, Dominica.
C. Minimum Height at Standard Level: 2,481m (8,140ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 107kts (~ 123.1mph)
E. Location of the Estimated Maximum Surface Wind Inbound: 13 nautical miles (15 statute miles) to the SSW (204°) of center fix
F. Maximum Flight Level Wind Inbound: From 304° at 116kts (From between the WNW and NW at ~ 133.5mph)
G. Location of Maximum Flight Level Wind Inbound: 15 nautical miles (17 statute miles) to the SSW (206°) of center fix
H. Minimum Sea Level Pressure: 930mb (27.47 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 7°C (45°F) at a pressure alt. of 3,045m (9,990ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 17°C (63°F) at a pressure alt. of 3,039m (9,970ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 12°C (54°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Closed
M. Eye Shape & Diameter: Circular with a diameter of 25 nautical miles (29 statute miles)
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile

Remarks Section:
Maximum Outbound and Flight Level Wind: 158kts (~ 181.8mph) which was observed 21 nautical miles (24 statute miles) to the NE (39°) from the flight level center at 11:26:00Z
Dropsonde Surface Wind at Center: From 115° at 12kts (From the ESE at 14mph)

[BlowHard]

First visible:

Good Morning, beautiful...

Beautiful? Sure wish I had the luxury of that emotion. This storm is about to blow apart the world of millions down here. In PR, we have been told to expect to be without electricity for up to three months.

[Ntxw]

Those wind numbers makes Irma the strongest Cyclone in 2017 on earth

If those sub 900 pressures from the GFS verify, how high will Irma's winds be? 200mph plus?

Maybe 190mph? I don't know if I quite believe the sub 900 numbers though. Still she's quite intense.

But looking at larger scale her cloud tops are not the coldest I've seen compared to in other basins. If this thing is 150kts+ with these color temps on BD, you just have to wonder what recon would find on the Pacific side. But I'm not sure if the wind connection is similar over there.

[Kingarabian]

11:38z
[img]https://i.imgur.com/jRBkspv.png[/mg]

Definition of horror.

[invest man]

GFS has been showing for days a very intense storm with winds and pressure being where it is now. Most of us could not really buy into it thinking it was in fantasy land. However a question for us is would the stronger lower pressure allow it the more probability to be more or less influenced by the trough and kick it more east or not be influenced at all by the trough and continue more westerly. Perhaps the strength of the storm is why GFS is showing a slight eastern path now. Just an observation.

[tolakram]

NHC has been using the Fl straights as a holding cell for Irma the last 3 advisories at 120hr. I would think they have to shift NE on next to show the turn into FL. Especially with the GFS well east.

its one run of the gfs, i doubt they bend it that hard to make landfall on the peninsula...if the euro shows an east trend then yes at 5 pm they will bend it

Hello ,

I am confused by this post, hasn't the GFS shown a peninsula hit the last 5 or 6 runs? sorry if i missed something i am trying to keep up

It's been on or close for the last 2 days (it runs 4 times a day). The blend is still up in the air, especially since the GFS at that range had significant errors this year. UKMET is now east of Florida, Euro still hits Florida very similar to the GFS. Need to get a few days closer to be sure.

[doomhaMwx]

Another early morning VIS satellite image...

[Kingarabian]

NOAA says 171 kt max-flight level on VDM.... Considering Air Force SFMR of 154 kt, this is probably a 155 kt hurricane. Incredible.

000
URNT12 KWBC 051129
VORTEX DATA MESSAGE AL112017
A. 05/11:10:54Z
B. 16 deg 42 min N
057 deg 41 min W
C. NA
D. 110 kt
E. 188 deg 12 nm
F. 297 deg 120 kt
G. 189 deg 17 nm
H. 930 mb
I. 14 C / 2453 m
J. 21 C / 2412 m
K. 16 C / NA
L. CLOSED
M. C23
N. 12345 / NA
O. 0.1 / 1 nm
P. NOAA2 0711A IRMA OB 10
MAX OUTBOUND FL WIND AND MAX FL WIND 171 KT 024 / 19 NM 11:16:47Z
MAX FL TEMP 21 C 012 / 6 NM FROM FL CNTR
CNTR DROPSONDE SFC WIND 265 / 10 KTS

This one will be for the books SouthDadeFish. Hopefully it'll be the last impressive VDM we'll ever see from Irma.

[WAcyclone]

There have only been six recorded Atlantic hurricanes stronger than Irma: Allen, Labor Day, Gilbert, Rita, Wilma and Mitch.

[OntarioEggplant]

Wow... Utterly amazing. Here I was making comparisons to Luis when this could be much worse than Luis in the islands. Hoping for the best for the people down there.

I'm pretty sure Irma is the strongest hurricane outside of the Gulf or Caribbean for many years now. I can't recall a category 5 hurricane with those wind speeds east of the islands... The closest I get is Hugo, but I don't think Hugo reached 175.

Irma's satellite presentation is gorgeous as well. It's unfortunate that it will inevitably cause great destruction.

[xtyphooncyclonex]

Is it tue stronger storms tend to follow the ridge more and are less suspectible to be easily pulled off by the trough?

[DelrayMorris]

My heart goes out to the people on the Islands... No matter where it goes later or how intense it gets... they are going to experience 175 mph as it probably won't see an ERC before it gets there.

The loss of life it going to be horrific.