Major Hurricane Irma

[SN_Lover]

From Radar, IR, and Recon it appears Irma is gaining latitude. Correct me if im wrong. 

[JasonOH]

6 minutes ago, jasons said:

Just an observation, the GOES-16 imagery is technically "non-operational," but they seem to be using it in an official capacity.

The offices use it for a bunch of forecasting purposes. It's great for fire and severe weather.  It's also been a great tool for canes, so they use it, even if it is "non-operational."  While it has brought amazing images from this storm, it will be really useful around landfall like it was for Harvey. Absolutely amazing tool in our toolbox.

[audioguy3107]

6 minutes ago, WesterlyWx said:

Is it just me or does it look like that things still heading just about due west from the beginning of the loop to the end? 

Probably just a wobble to the west, if you look closely at the AVN satellite loop from NHC, it still looks to be heading WNW overall.  A big wobble to the west puts Puerto Rico in danger but if it keeps on the current heading it looks like Irma will pass just to the NE of the island.  Close call though.

[NavarreDon]

Is it just me or does it look like that things still heading just about due west from the beginning of the loop to the end? 

Slightly N of due W. That being said it better start with a WNW & NW or PR is going to come into play.


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[Baroclinic Zone]

3 minutes ago, Wow said:

True, but yet they nearly all end up in upstate SC.  The UL working it.

FL impacts would be dramatically different with those 2 scenarios though.

[Windspeed]

The Guadeloupe radar appears to show two concentric return maxima. Oddly the HMON had been simulating that structure for awhile now. But, the microwave imagery doesn't really suggest that an ERC is taking place or is imminent. 

Based on radar imagery, the OEW and IEW are both intense with very little separation or "moat". The close proximity and intense structure may be just showing up as one very large intense band on microwave around the core.

[SACRUS]

 

Barbuda and Antigua N/S

 

[Random Chaos]

That central deep covection is now a perfectly smooth donut - on the outer edge too - wow - never seen something like that, even with past annular hurricanes:

[Wow]

4 minutes ago, Baroclinic Zone said:

FL impacts would be dramatically different with those 2 scenarios though.

Correct.. FL is going to be very tough to figure out at this stage.

[winterymix]

Best two recent track analogues:

Donna  1960

David 1979

[Drz1111]

2 minutes ago, Random Chaos said:

That central deep covection is now a perfectly smooth donut - on the outer edge too - wow - never seen something like that, even with past annular hurricanes:

You must be a babe then, because his storm has nothing on Luis or Isabel for axisymmetric  asthetics.

[amc]

28 minutes ago, No snow for you said:

Move this if needed but Anguilla has cut all power to the island and cell service is already out. Getting some updates via sat phone. They are very scared now from what I was told 

Why would they purposely cut cell service? Power I guess I understand....

[bdgwx]

2 minutes ago, Windspeed said:

10 minutes ago, bdgwx said:

The Guadeloupe radar appears to show two concentric return maxima. Oddly the HMON had been simulating that structure for awhile now. But, the microwave imagery doesn't really suggest that an ERC is taking place or is imminent. 
 

Based on radar imagery, the OEW and IEW are both intense with very little separation or "moat". The close proximity and intense structure may be just showing up as one very large intense band on microwave around the core.

Good point. At any rate there must be some interesting dynamics going on in there right now. Boy, I sure would love to have a WSR-88D radar on one of those islands right now.

[LakeEffectKing]

In nearly 40 years of observing hurricanes intensively, this is #1 on the awe scale.  Truly a natural wonder!

But back on to the meteorology of it.  When this comes into the US Doppler Radar range, (assuming it has little land interaction), I no doubt believe we will see 2, maybe three concentric "eyewalls"...ie a CAT 5 within a Cat 2, within a TS...All the models show this storm growing in size, all the while lowering the pressure of the outer portions of the system....I do believe we will go sub-900 north of Cuba (again assuming no LF/little land interaction....that said, I think we are at or near the peak of max winds....(maybe we touch 200mph), but needless to say, even at 140-150 max (and a large core of hurricane force winds or higher) this has a very high potential of demonstrating effects like we haven't seen since 1935.

[RU848789]

9 minutes ago, Chinook said:

The radar I am looking at (Caribbean composite) shows about 0.1 deg latitude gain from beginning to end of loop.  That should put the center very close to Barbuda.

Good eyes.  At 5 pm AST, NHC had Irma at 17.1 north and at 8 pm, it is at 17.2 north, which is 0.1 deg latitude in 3 hours. Projection is for it to be at 17.6 N in 9 hours, which would be a little more than 0.1 degree north every 2 hours, i.e., a bit more northerly than the 0.1 degree north we saw in the last 3 hours.  We'll see - further north the better for everyone, except the Bahamas, I guess.  

[No snow for you]

1 minute ago, amc said:

Why would they purposely cut cell service? Power I guess I understand....

They take down the towers so they can save them from the storm and put them back up later. 

[HoarfrostHubb]

2 minutes ago, winterymix said:

Best two recent track analogues:

 

What storms are these?

[mfgmfg]

2 minutes ago, amc said:

Why would they purposely cut cell service? Power I guess I understand....

Scheduled shutdown of equipment and taking down of cell towers to spare the equipment.

[winterymix]

1 minute ago, HoarfrostHubb said:

What storms are these?

David 1979. lower image

Donna 1960 upper image

[donsutherland1]

After another day of watching Irma, I still think that the Florida-South Carolina area remains at the highest risk of U.S. landfall from Irma (though the larger area at some risk of landfall extends from the Florida Panhandle to the Outer Banks of North Carolina; outside that area the risk seems low). I note the 18z GFS, but it seems to be an outlier both among its ensembles and the other guidance.

I also have little change in my thinking that the probability of U.S. landfall is around 75%.That is now close to the 73% figure from historical climatology for all major hurricanes passing within 100 nautical miles of Irma's 5 pm position (1851-present) and somewhat below the implied outcome of the 12z ECMWF ensembles.

In terms of historic climatology, 7/8 (88%) of the hurricanes that made landfall from the above-referenced sample made landfall in the Florida-South Carolina area and 6/7 (86%) of those hurricanes had Florida landfall.

Half of the hurricanes that made Florida landfall made prior landfall over Cuba.Those that made landfall in Cuba were Category 1 or Category 2 storms upon Florida landfall. Two of the three hurricanes that did not make landfall on Cuba came ashore in Florida as Category 4 storms (the 1928 Okeechobee Hurricane and Donna in 1960). A category 4 Florida landfall still seems more likely than a Category 1 landfall.
 

[csnavywx]

6 minutes ago, LakeEffectKing said:

In nearly 40 years of observing hurricanes intensively, this is #1 on the awe scale.  Truly a natural wonder!

But back on to the meteorology of it.  When this comes into the US Doppler Radar range, (assuming it has little land interaction), I no doubt believe we will see 2, maybe three concentric "eyewalls"...ie a CAT 5 within a Cat 2, within a TS...All the models show this storm growing in size, all the while lowering the pressure of the outer portions of the system....I do believe we will go sub-900 north of Cuba (again assuming no LF/little land interaction....that said, I think we are at or near the peak of max winds....(maybe we touch 200mph), but needless to say, even at 140-150 max (and a large core of hurricane force winds or higher) this has a very high potential of demonstrating effects like we haven't seen since 1935.

She might make a run at 200 tonight. If not, there's another slight chance near the Bahamas where the SSTs are a bit warmer and an extra outflow channel opens.

[JC-CT]

That central deep covection is now a perfectly smooth donut - on the outer edge too - wow - never seen something like that, even with past annular hurricanes:

Haiyan had that look, except a few shades different.

[NorthArlington101]

[CaWx]

So drop sounde found a wind reading of 192mph at the surface? Why wouldn't the NWS update accordingly? Would beat Allen would it not? 

[JasonOH]

Just now, CaWx said:

So drop sounde found a wind reading of 192mph at the surface? Why wouldn't the NWS update accordingly? Would beat Allen would it not? 

The splash wasn't 134mb, it ended up being 137mb. There was no wind data at splash, so it didn't show up on Tropical Tidbits due to the way the site is coded, but did show up on other sites.  

[dan11295]

1 minute ago, CaWx said:

So drop sounde found a wind reading of 192mph at the surface? Why wouldn't the NWS update accordingly? Would beat Allen would it not? 

That reading was a few mb above the surface

[LakeEffectKing]

Just now, csnavywx said:

She might make a run at 200 tonight. If not, there's another slight chance near the Bahamas where the SSTs are a bit warmer and an extra outflow channel opens.

Maybe, but as this gains latitude, the ability to shrink an eye should diminish, especially with the large wind field...but this is an extreme cane....so maybe there are some surprises to be had.  Of course there is the fear, sadness of the almost inevitable loss, but as a scientist, this storm as is, and as it has been modeled, is incredibly fascinating... 

[Chinook]

It would seem that the latest eyewall pass on Recon mission #11 has about 156kt, surface, SFMR measurement, if I am reading the graph right. That's 179.5mph. It seems somewhat consistent with other values of 145-160 kt today (160kt was highest advisory value today, i.e, 185mph)

[HO1088]

The updated TAF for St. Maarten forecasts wind gusts to 160 knots from 07Z-11Z.  

[Bostonseminole]

3 minutes ago, dan11295 said:

That reading was a few mb above the surface

it was like 3mb above the surface.. I think we see 190mph at 11pm.. we should see another pass by recon soon