Hurricane Irma

[Ice Day]

 

Michael Ventrice‏Verified account @MJVentrice  20m20 minutes ago

Major Hurricane #Irma has been officially upgraded to a Category 4 Hurricane with 130mph winds; That is the 2nd Cat-4 storm of the year.

[Chris.R]

7 minutes ago, Iceberg said:

http://www.nhc.noaa.gov/text/MIAREPNT2.shtml

 Thanks :-) quite new to hurricane tracking so don't have that many bookmarks to go on. 

[Ice Day]

Irma must be giving some major headaches all across the Caribbean and the US.  A direct hit on South East Florida as a Cat 4/5 would be extremely destructive but having it skirt slightly south and up into the Gulf of Mexico would be equally as worrying (although that's an outlier at the moment).  

[knocker]

[knocker]

 

[summer blizzard]

Stunning core. Amazing to think some of the islands are going to take the full force of that. 

The past 24 hours have seen hurricane force winds expand (now 40 miles) but the tropical storm/size of the system remains the same (now 140 miles). 

[summer blizzard]

Two things.. 

1) Recon have found that Irma is still moving slightly south of west. 

2) GFS18Z hits Miami at 892mb. Andrew probably looks like a soft little baby in that scenario. 

[crimsone]

7 minutes ago, summer blizzard said:

Two things.. 

1) Recon have found that Irma is still moving slightly south of west. 

2) GFS18Z hits Miami at 892mb. Andrew probably looks like a soft little baby in that scenario. 

Still feeling like the GFS underestimates the shredding effect of the Cuban mountains... though there is a patch of lower ranges in the middle of the island that aren't quite as "bad".

[toggerob]

Latest windyty forecast is out, the core of Irma being jogged westwards towards FL yet again

[summer blizzard]

14 minutes ago, crimsone said:

Still feeling like the GFS underestimates the shredding effect of the Cuban mountains... though there is a patch of lower ranges in the middle of the island that aren't quite as "bad".

It's unlikely they'll have much effect if the inner core avoids them. All they'll do is make the system look a bit ugly if it simply catches the banding. 

[cheese]

Florida is well overdue a major hurricane.. hope they haven't forgotten how to prepare for them! Last was Wilma in '05..

Edited September 4, 2017 by cheese

[summer blizzard]

3 minutes ago, cheese said:

Florida is well overdue a major hurricane.. hope they haven't forgotten how to prepare for them! Last was Wilma in '05..

Timely post.. Governer of Florida just declared a state of emergency. 

[AderynCoch]

35 minutes ago, crimsone said:

Still feeling like the GFS underestimates the shredding effect of the Cuban mountains... though there is a patch of lower ranges in the middle of the island that aren't quite as "bad".

GFS 18z is keeping the core of Irma just offshore of Cuba; ECM is closer to the island but the eye still just misses landfall. I'm not sure how close the storm would have to get for its circulation to become significantly disrupted but I can see only minimal weakening at this point. Of course Florida's gain would be Cuba's loss and it doesn't look like there's any scenario on the table which would avoid at least one intense landfall (if Irma manages to stay east of Florida it's very likely it will hit at least one of the Bahamas on the way, probably Andros).

Regarding intensity, while the GFS is clearly smoking something the ECM if anything looks undercooked to me. It's showing 960+mb until it passes Puerto Rico and still only 950mb on approach to Cuba - yet it's already down to 944mb. Do the models factor in EWRCs? I'm not sure what else could account for the rise in pressure, as conditions in the days ahead only look favourable for strengthening.

Edited September 4, 2017 by AderynCoch

[Frost HoIIow]

19 minutes ago, SNOW_JOKE said:

Latest windyty forecast is out, the core of Irma being jogged westwards towards FL yet again

That is pretty worrying for Miami. When was the last direct hit in Miami? was it Andrew in 1992?

[AderynCoch]

Just now, Frost HoIIow said:

That is pretty worrying for Miami. When was the last direct hit in Miami? was it Andrew in 1992?

Last major hurricane to hit Miami I think. Wilma was Cat. 3 at landfall in SW Florida but weaker as it passed eastwards over the city.

Andrew was a 5 but the strongest winds were south of downtown Miami (poor Homestead got flattened).

[summer blizzard]

6 minutes ago, AderynCoch said:

GFS 18z is keeping the core of Irma just offshore of Cuba; ECM is closer to the island but the eye still just misses landfall. I'm not sure how close the storm would have to get for its circulation to become significantly disrupted but I can see only minimal weakening at this point. Of course Florida's gain would be Cuba's loss and it doesn't look like there's any scenario on the table which would avoid at least one intense landfall (if Irma manages to stay east of Florida it's very likely it will hit at least one of the Bahamas on the way, probably Andros).

Regarding intensity, while the GFS is clearly smoking something the ECM if anything looks undercooked to me. It's showing 960+mb until it passes Puerto Rico and still only 950mb on approach to Cuba - yet it's already down to 944mb. Do the models factor in EWRCs? I'm not sure what else could account for the rise in pressure, as conditions in the days ahead only look favourable for strengthening.

The Euro only grants accurate pressure data to it's high res customers so you kind of have to knock a bit off. 

[AderynCoch]

Thanks SB. So would 935mb be a reasonable guess as it first nears the Bahamas/Cuba?

[summer blizzard]

20 minutes ago, AderynCoch said:

Thanks SB. So would 935mb be a reasonable guess as it first nears the Bahamas/Cuba?

Realistically, it's hard to see how it does become a category 5 hurricane. 

By day 5, shear is no higher than now but the storm is slower, in a more moist environment and in warmer seas.

[crimsone]

latest recon...

 

000
URNT12 KNHC 042343
VORTEX DATA MESSAGE   AL112017
A. 04/23:23:40Z
B. 16 deg 42 min N
  054 deg 57 min W
C. 700 mb 2594 m
D. 104 kt
E. 195 deg 12 nm
F. 285 deg 99 kt
G. 197 deg 14 nm
H. 944 mb
I. 11 C / 3051 m
J. 16 C / 3050 m
K. 10 C / NA
L. CLOSED
M. C30
N. 12345 / 7
O. 0.02 / 1 nm
P. AF305 0611A IRMA               OB 04
MAX OUTBOUND AND MAX FL WIND 135 KT 033 / 15 NM 23:29:40Z
CNTR DROPSONDE SFC WIND 125 / 12 KT
;

Edited September 4, 2017 by crimsone

[Gael_Force]

1 hour ago, AderynCoch said:

Thanks SB. So would 935mb be a reasonable guess as it first nears the Bahamas/Cuba?

The ECM has it as low as 926mb between the Bahamas and Cuba. There's more detailed close up charts on the US weather site.

[toggerob]

I can't recall a CAT5 hitting directly over Miami, although I was browsing youtube earlier this evening looking at some documentaries about Andrew with the general consensus being that should Miami get a direct hit it would completely devastate the city from not only the floodwaters, but the infrastructure and tourism hit. 

[Iceberg]

The strongest winds I've seen from a recon pass this year. This is the ne quad and would give 120kt to 125kt surface. 

Cat 5 is coming into view. 

[Iceberg]

Looks like nhc have reacted to this real time in this advisory 120kt surface speeds now. 

[East_England_Stormchaser91]

GFS is very worrying yet again. We see Irma unthinkably nearly getting into the gulf on the 00z. possibly a floridians worst nightmare about to come true if it was to slam Miami and then wreak havoc up the western coast :/ 

[Ice Day]

Irma is really getting getting it's actually together over the last few hours.

 

Edited September 5, 2017 by Ice Day