atlantic hurricane season Atlantic hurricane season/invest thread

[summer blizzard]

Interestingly it looks like tropical cyclone heat potential is at near record levels in the Atlantic and Carribean this year.

Latest Nina update still had enhanced westerlies over the Pacific so will probably have to wait a while for the Atlantic to wake up. . 

[mezzacyclone]

Maybe not so? (SB above)

some model consensus with a  closed low coming off guinea next mid-week,

some going fishy with continuing thru the MDR with a nw run up to bermuda but some show a lesser antiles track with a more vigorous   Azores ridge,

something to watch at least following the plague of current saharan dust inhibiting development in what was an active start!

for what its worth:

*update 210716* gfs weakened this on the next 2 runs then dropped it altogether,

so we are back to scratching a continuing stable MDR plagued by SAL for the tiniest signs,

it reminds me of the old eventless mr bartlett days :/ lol

Edited July 21, 2016 by mezzacyclone

[summer blizzard]

GFS does form a system of some sort as early as day 6 although once it cuts off from the ITCZ it quickly hits dry air and dies.

[mezzacyclone]

14 hours ago, summer blizzard said:

GFS does form a system of some sort as early as day 6 although once it cuts off from the ITCZ it quickly hits DRY AIR and dies.

Despite the addage "one basin being active = other inactive" then is NE US /SE Canadian troughing a big player in encouraging stable sinking SAL ridden air throughout the MDR by elongating AH more?

as quoted then maybe its more worthy to concentrate short term on the caribbean/GOM & the v high sst's for vorticity to develop on a remnant AEW until the epac levels of instability level off closer?

putting a line through most of July now on for Atl activity?

Edited July 24, 2016 by mezzacyclone

[summer blizzard]

58 minutes ago, mezzacyclone said:

Despite the addage "one basin being active = other inactive" then is NE US /SE Canadian troughing a big player in encouraging stable sinking SAL ridden air throughout the MDR by elongating AH more?

as quoted then maybe its more worthy to concentrate short term on the caribbean/GOM & the v high sst's for vorticity to develop on a remnant AEW until the epac levels of instability level off closer?

putting a line through most of July now on for Atl activity?

Yeah. Unless that thing actually forms and makes TS then July is a wright off. 

GFS has been suggesting something past day 10 but that could just be fodder.

 

[cheese]

Will this be another year without a hurricane landfall in Florida I wonder? Last one was in October 2005, Hurricane Wilma (and what a storm she was).

Edited July 24, 2016 by cheese

[mezzacyclone]

15 hours ago, cheese said:

Will this be another year without a hurricane landfall in Florida I wonder? Last one was in October 2005, Hurricane Wilma (and what a storm she was).

The million $ question!

& yes, 2005 was quite a year wasnt it!

I'm in the opinion that we are beginning a "state of flux" as it were? but that can easily tie in to the usual timeframe where a flat july precedes a more (how much?) active august for development.

the current ACE value of 6.8 for the ATL will surely mount in the next few weeks but if this relates to the mjo returning to phase 1&2, la nina impending in august, the short term heightened shear pattern in the EPAC, Anomolously high caribbean/GOM SST's & many factors mentioned in above posts affecting the ITCZ Then they all have some impact, the models are now picking up on traces for certain but only to drop "fantasy island" fashion with little general consensus at the current minute.

Not to allay & overhype but certain posters, (FL area residents) on other forums talk of a "ticking time bomb" & a matter of not "if" but "when" a major 'cane landfalls?

but if anything id generalise saying the cups "half full" now from "half empty" in terms of cyclonic energy potential in the (most interesting) Atl basin as we approach August & the fleeting closed lows showing up on most of the models & ens reflect this attitude.

noteworthy of nhc's lessening of EPAC mid-term forecast activity!

case of identifying the tiniest short term agreement in a given area, florida to carolinas east coast & northern & eastern GOM for me

 

 

[summer blizzard]

I'll be making my usual basic anologue forecast for the numbers this week but it would be highly unlikely for a neutral/Nina season to produce anything other than an average to above average August-October.

[Gael_Force]

Levi Cowan has added hurricane season analogues to his web site. Would you be thinking similar to his?

http://www.tropicaltidbits.com/analysis/hsanalog/

 

[summer blizzard]

Adding in the fact that we've seen 4 tropical storms so far my forecast is..

14-16 named storms

6-8 hurricanes

2-4 major hurricanes

[mezzacyclone]

10 hours ago, summer blizzard said:

Adding in the fact that we've seen 4 tropical storms so far my forecast is..

14-16 named storms

6-8 hurricanes

2-4 major hurricanes

Of which how many would you see as fish?

interestingly high amplitude to the monsoon trough over Africa currently!

Organised deep convection & high as 20'N lat, this should increase wv & restrict the affect of SAL as this AEW heads west 'tord CV & is raising short term TC activity for the tropical atlantic area reflected in data mods:

Nhc will no doubt be following these latest batch of waves particularly with epac genesis calming down?

Edited July 27, 2016 by mezzacyclone

[mezzacyclone]

Well its up!

The latest meaty pouches might not be sprouting VHT's but NHC are on with the microwave imagery & following the far eastern atlantic with 10% 48hr  & 20% 5 day development chances.

the basin wakens from her siesta? 

 

Edited July 27, 2016 by mezzacyclone

[summer blizzard]

GFS kills it in a few days. 

[mezzacyclone]

34 minutes ago, summer blizzard said:

GFS kills it in a few days. 

NHC bullish?

96L is currently a shallow system at 10.2N 17.6W ,1011mb headed W around 25mph with a wind radius of 60 naut miles maxing out at 23mph but with clear closed low winds.

40% through 5 days may reflect nothing currently severe to impede development so every chance to keep it intact across the mdr?

in the very least Id say we can all agree on the next batch exiting W Africa are something intriguing to follow given current conditions?

 

 

 

[summer blizzard]

36 minutes ago, mezzacyclone said:

NHC bullish?

96L is currently a shallow system at 10.2N 17.6W ,1011mb headed W around 25mph with a wind radius of 60 naut miles maxing out at 23mph but with clear closed low winds.

40% through 5 days may reflect nothing currently severe to impede development so every chance to keep it intact across the mdr?

in the very least Id say we can all agree on the next batch exiting W Africa are something intriguing to follow given current conditions?

 

 

 

Interesting. Possibly there higher resolution (non public) models are making more of it. 

I suspect that the two biggest threats to it are it's speed (hard to avoid a tilted vortex) and dry air. 

[mezzacyclone]

1 hour ago, summer blizzard said:

Interesting. Possibly there higher resolution (non public) models are making more of it. 

I suspect that the two biggest threats to it are it's speed (hard to avoid a tilted vortex) and dry air. 

Steering trades are forecast to lessen slightly from 25mph to 15-20mph if that would aid dev? but talk suggests the next pouch will favor yet more from 96 here "clearing out" the dry (sal) environment but previous to this current one then the last few days have seen waves encroach into the sal & aid every following aew with more wv and/or less drier/dusty air?

(seem to recall reading somewhere that vortical high towers, fundamental to TS genesis?, can form & maintain in up to 10kn of horizontal steering winds so it could be borderline "touch n go"?)

i'm not a "hamper" (hurricane wisher)  but i havnt seen the NHC back down on an "orange" severity many times!

Edited July 27, 2016 by mezzacyclone
Spelling

[mezzacyclone]

#UPD# Another area of drier dusty air is plotted to leave western sahara/mauritania through friday so this maybe a factor why the models suppress 96L development between 40-60 degs W as this sal plume catches up & gets ingested, increasing shear on the latest runs in the western tropical atlantic is also now appearing but mid-long term shear forecasts are prone to innaccuracy so anythings possible further down the line.

 

Edited July 27, 2016 by mezzacyclone

[mezzacyclone]

Ok, to further complicate matters, the wave prior to what became 96L is now up with invest 97L , a few hundred miles due W OF 96.

theirs a multiude of circumstances such as RH & OHC thrown into the current mix to decide the outcome of both these potential developments besides the usual foreplayers so i hope one or both of them reach TD status With a confirmed LLC (although 96l had/has some mid-level circulation?) so we can have seperate threads? :/

personally i dont have a clue as to which or both of these reaches the 60W longitude boundary entry into the caribbean etc intact at the minute?

 

[summer blizzard]

At their current speeds i don't think either makes it. GFS picks up both but 97L has no spin, 96L currently has cloud tops of -80C and has spin but dies (probably because it never has a proper vortex). 

[mezzacyclone]

10 hours ago, summer blizzard said:

At their current speeds i don't think either makes it. GFS picks up both but 97L has no spin, 96L currently has cloud tops of -80C and has spin but dies (probably because it never has a proper vortex). 

97 looks paltry this morning yes but 96 has popped an impressive looking mcs overnight on its merry itcz train:

 

 

[summer blizzard]

Looks like a TD to me but perhaps there's no closed circulation..

[summer blizzard]

96L now at 50% for 5 day development.

[knocker]

Twin Invests 96L and 97L Worth Watching in the Atlantic

Quote

There's a new threat area to discuss today in the Atlantic: a tropical wave midway between the Lesser Antilles Islands and the Cabo Verde Islands that is headed west to west-northwest at 25 mph. This disturbance was designated Invest 97L on Thursday afternoon by NHC, and should arrive in the northern Lesser Antilles by late Saturday night. The Hurricane Hunters are on call to investigate the storm on Sunday, if needed. Satellite loops on Friday morning showed 97L had a modest area of heavy thunderstorms which were poorly organized, though there was some increasing spin evident in the cloud pattern. Wind shear was a light 5 - 10 knots, and sea surface temperatures (SSTs) was an adequate-for-developement 27°C (81°F), which was about 1°C (1.8°F) above average. Water vapor satellite imagery showed that 97L had a modest amount of dry air from the Saharan Air Layer (SAL) surrounding it, which was slowing development.

https://www.wunderground.com/blog/JeffMasters/twin-invests-96l-and-97l-worth-watching-in-the-atlantic

[summer blizzard]

Ships actually has a pretty good environment for 97L if it actually makes it to day 4 and avoids being shredded. 

[Nouska]

UKMO the only model to show something more organised by day seven, into Mexico but is it 96 or 97 - cannot work it out.

Is that a suggestion of energy coming off the CONUS and developing home grown near Carolinas coast?

http://ruc.noaa.gov/hfip/tcgen/