atlantic hurricane season Atlantic hurricane season/invest thread

[AderynCoch]

I'm flying to Miami on the 15th. I really want 99L to die a quick death.

[knocker]

 

[knocker]

 

[matty40s]

I'm a big hurricane fan but Michael Ventrice is like the boy crying wolf.

He's bound to get one eventually........maybe this year ...

[knocker]

6 hours ago, matty40s said:

I'm a big hurricane fan but Michael Ventrice is like the boy crying wolf.

He's bound to get one eventually........maybe this year ...

That's as maybe but what I find of interest is that the ecm is currently taking it as a TC into our neck of the woods and the gfs is showing absolutely zilch

[Summer Sun]

Franklin Becomes First Atlantic Hurricane of 2017

https://weather.com/storms/hurricane/news/hurricane-franklin-forecast-mexico-august-2017-atlantic?cm_ven=T_WX_CD_80917_1&hootPostID=1b684d04f6da00bd7d727cb1972ba6d6

[Gael_Force]

Amazing detail of 99l from the new Goes16 satellite.

[summer blizzard]

TD8 has formed but will FISH in a few days.

..

Interestingly we have a strange set of events this year so far in that global cyclone activity is running at ~70% of average consistent with a background La Nina pattern.. however abnormally the only basin to be running above average is actually the East Pacific rather than Atlantic. 

This could just be a fluke that will resolve itself over the season but if not then it's a strange set of events. 

[knocker]

 

[JeffC]

love this visualisation of Gert - https://earth.nullschool.net/#current/wind/surface/level/overlay=temp/orthographic=-58.29,29.90,669/loc=-71.198,27.844

 

[Gray-Wolf]

So it's all eyes on 91L then?

I suppose Gert is what we are looking for in the UK if we want a chance at shifting this cool jet trough over us? Maybe it could back track and leave us under a ridge the rest of summer now?

As for 91L I think I can already see rotation so let's see how long it takes to get itself organised?

[knocker]

Well this is Gert combining with another low over NE canada and later from the GEFS 06Z. As we know the gfs is currently very much at odds with the ecm next week

 

The latest musing from RM

 

Edited August 14, 2017 by knocker

[mb018538]

Looks like we're getting to the time when model output gets throw into complete chaos, especially if we have a number of curveball systems like Gert & a possibility with Irene. As knocker says above, this is causing the big model disagreements that we are seeing at present as to how these interact nearer our shores.

[Gael_Force]

Goes16 on 91l.

https://weather.msfc.nasa.gov/cgi-bin/get-abi?satellite=GOESEastfullDiskband02&lat=14&lon=-40&width=1400&height=900&zoom=4&type=Animation&numframes=15&quality=90

 

Edited August 14, 2017 by Gael_Force

[knocker]

 

[summer blizzard]

Gert is now a hurricane.

[summer blizzard]

Interestingly this season is actually running in 5th place so far for named storms, though ACE is running below average. 

We have 3 waves. Two at 40% and one at 20%. 

[summer blizzard]

To add to 91L and 92L..

91L has a problem in that it will speed up out to 5 days (normal around the islands) which will make it harder to form a coherent core. The plus side is that the atmosphere is mildly moist (could be better, could be worse) and heat content will increase. Shear remains light to moderate (relative shear increases with increased speed).

92L has moderate shear ahead but increased heat content and a more reasonable speed. Once it no longer has 91L in front of it (it is destined to FISH) the atmosphere becomes drier though. 

Both have their good and bad points.

91L is probably more developed than most waves headed for the Carribean so that gives us hope that we could see Ernesto/Franklin once it gets south of Cuba and things slow down (the atmosphere is generally moist there too) but that is probably a week away. 

92L probably has the better chance of formation this week but is unlikely to strengthen at any real rate if it does so however it should be a pretty long track system and if it develops quicker then as Gert shows, we could end up with a strong system in a weeks time.

In conclusion - time is probably our friend. 

[Cleeve Hill]

An update from me in Antigua. 

There was a tropical wave that came through on 7th Aug, which had minimal effects here but in the BVI (less than 1 hour flight) it brought flash floods and destruction in Road Town. The terrain in the BVI is v hilly to "run off" is the problem there. 

Insurers had loss adjusters and claims teams on the ground. My point being you dont need a TS or Hurricane to cause an "event". 

The next 2 weeks looks interesting. There are the two systems on the map and another about to come off the african coast. 

Its looking a lively season. There have only been 3 years where the G named storm was before 13th Aug. 

[Cleeve Hill]

Gert is now a Cat 2. Its intensifying as it leaves the warmer waters. SST must still be 80f but quite unusual to be so far north and still have its tropical characteristics. 

[summer blizzard]

Gert is now a 100mph hurricane (cat 2). It looks like there's probably some barlonic forcing as it has attached itself to the rear of a cold front and is racing north east but with shear from a westerly direction and a moist atmosphere it looks like Gert has been loving the conditions and the tail wind. 

91L, 92L and 93L are all 50% in 5 days. 

Most interestingly it looks like 91L may have developed a closed low (though barely any precipitation) so recon will be in tomorrow. 

[summer blizzard]

91L has now been upgraded to 70% and recon is in today. Convection over the center could be better so i suspect they won't declare but the islands may get some kind of watch. 

The operational models don't really do much with it (GFS has a strong wave, Euro has a TS hitting Belize) but the SHIPS diagnostic is fantastic.. by day 5 it has 30C waters, 9KT shear, a moderate system speed and humidity of 77% (it's closer to 40% now). The Euro ensemble tracks are also pornographic.

If a coherent system does form then we could be looking at at least Ernesto (2012). 

[knocker]

 

[summer blizzard]

Gert is now post-tropical. 

91L however has been declared Tropical Storm Harvey. 

Future strength essentially depends on whether it moves west faster than a ridge to its north which may impart northerly shear. Statistical models love Harvey, global models hate it. NHC have gone for the middle ground. 

[karyo]

8 hours ago, summer blizzard said:

Gert is now post-tropical. 

91L however has been declared Tropical Storm Harvey. 

Future strength essentially depends on whether it moves west faster than a ridge to its north which may impart northerly shear. Statistical models love Harvey, global models hate it. NHC have gone for the middle ground. 

The 0z ECM also loves Harvey and places him in the gulf of Mexico in 10 days time.