[HurricaneJosh]

The fish are getting well-fed this year. Whatever!

[jconsor]

Based on past history, the likelihood of getting a hurricane in Oct or Nov of this year is relatively high (about 75%). Since 1900, there have been 16 years that featured weak a weak El Nino during the summer and fall. 12 had at least 1 hurricane during Oct-Nov, and of those, 4 had 2 hurricanes and 1 (1969) had 4 hurricanes. Of the years that had no hurricanes, 3 were in the positive phase of the PDO. Currently, we are in a negative PDO phase.

However, the chances of a major hurricane during Oct-Nov are much lower than normal during weak El Ninos. Only one of the 16 years, 1941, had a major 'cane.

(Note: I define a weak El Nino as an 5-month average SST anomaly between 0.6 and 1.2 for July-November, based on the JMA SST index: ftp://www.coaps.fsu..../JMA_SST_Index/).

We need to watch the Western Caribbean carefully, as the MJO is now in a favorable mode there, and the MJO doesn't look to move significantly in the next week or so. Shear is currently quite high, but is expected to decrease by mid-late next week. The latest ECMWF has backed off somewhat on the favorable 200 mb pattern there for mid-late next week, but the 4 runs prior to the current one have shown gradual tropical cyclone development off the Nicaragua coast.

There is also a decent chance of subtropical development in the NE Atlantic (similar to 2008's Laura) as a cutoff low moves south to a position WSW of the Azores and gets trapped underneath a blocking ridge over Greenland. Both the GFS and GEM show this cutoff becoming marginally warm core by late next week: http://moe.met.fsu.edu/cyclonephase/

[HurricaneJosh]

jconsor, on 26 September 2009 - 01:53 PM, said:

Based on past history, the likelihood of getting a hurricane in Oct or Nov of this year is relatively high (about 75%). Since 1900, there have been 16 years that featured weak a weak El Nino during the summer and fall. 12 had at least 1 hurricane during Oct-Nov, and of those, 4 had 2 hurricanes and 1 (1969) had 4 hurricanes. Of the years that had no hurricanes, 3 were in the positive phase of the PDO. Currently, we are in a negative PDO phase.

However, the chances of a major hurricane during Oct-Nov are much lower than normal during weak El Ninos. Only one of the 16 years, 1941, had a major 'cane.

(Note: I define a weak El Nino as an 5-month average SST anomaly between 0.6 and 1.2 for July-November, based on the JMA SST index: ftp://www.coaps.fsu....-today.filter-5).

We need to watch the Western Caribbean carefully, as the MJO is now in a favorable mode there, and the MJO doesn't look to move significantly in the next week or so. Shear is currently quite high, but is expected to decrease by mid-late next week. The latest ECMWF has backed off somewhat on the favorable 200 mb pattern there for mid-late next week, but the 4 runs prior to the current one have shown gradual tropical cyclone development off the Nicaragua coast.

There is also a decent chance of subtropical development in the NE Atlantic (similar to 2008's Laura) as a cutoff low moves south to a position WSW of the Azores and gets trapped underneath a blocking ridge over Greenland. Both the GFS and GEM show this cutoff becoming marginally warm core by late next week: http://moe.met.fsu.edu/cyclonephase/

Interesting stats-- thanks for sharing. The ECMWF hints are particularly interesting to me-- as some of the Atlantic's most severe 'canes form in the W Caribbean in October. It's hard to imagine the Caribbean finally activating this year-- but I'll keep hope alive.

P.S. Right next door, the E Pac is also alive with convection right now.

[rainstorm]

i will check it out richard.

[wx4cast]

wnrichard583, on 26 September 2009 - 04:20 PM, said:

-

Something new, cropping up out past 40° west. (?)

With main colder air retracting at this point, shearing should be less of a factor.

Also as I see it (.. as with main colder air's more latitudinal propensity at this point) main "cooler" air's more longitudinal movement east, should be moving progressively more slowly through to the first of Oct. or so.

http://aviationweather.gov/data obs sat intl ir ICAO-A bw.jpg - single image.
http://aviationweather.gov/obs sat intl/
(.. check, loop mode for "Area A".)


-

Now in English please?

[40/70 Benchmark]

HurricaneJosh, on 26 September 2009 - 02:01 PM, said:

Interesting stats-- thanks for sharing. The ECMWF hints are particularly interesting to me-- as some of the Atlantic's most severe 'canes form in the W Caribbean in October. It's hard to imagine the Caribbean finally activating this year-- but I'll keep hope alive.

P.S. Right next door, the E Pac is also alive with convection right now.

This season FTL

[flwxwatcher45]

Things look really bleak but after reading some input from some Pro Mets in the classic MJO and Kelving Wave signal thread I am holding out some hope of a possible late season system close to home to save the season.. :whistle:

[~Floydbuster]

Just wait 'till 2010. Bonnie, Earl, Gaston, Hermine...IGOR...we can't let those names go to waste! :P

[Calderon]

~Floydbuster, on 28 September 2009 - 10:38 AM, said:

Just wait 'till 2010. Bonnie, Earl, Gaston, Hermine...IGOR...we can't let those names go to waste! :P

Ha, the 04 list, with some name adjustments.

[kalebtreuman]

Yuck.

http://www.ssd.noaa.gov/goes/east/catl/avn-l.jpg

http://www.ssd.noaa.gov/goes/east/nwatl/avn-l.jpg

[newB]

Pitching a shutout through 6....

[EyeWantaHurricane]

This is so depressing. :gun_bandana: :gun_bandana: :gun_bandana:

[wxeyeNH]

Seems intertropical convergance zone in the mid Atlantic is getting a bit more active. Any thoughts?

[kalebtreuman]

wxeyeNH, on 30 September 2009 - 12:29 PM, said:

Seems intertropical convergance zone in the mid Atlantic is getting a bit more active. Any thoughts?

http://www.ssd.noaa.gov/goes/east/catl/avn-l.jpg

You never know... October could have 1 or 2 storms.

[flwxwatcher45]

kalebtreuman, on 30 September 2009 - 01:23 PM, said:

http://www.ssd.noaa.gov/goes/east/catl/avn-l.jpg

You never know... October could have 1 or 2 storms.

The GFS is hinting at maybe something in the Caribbean/Gulf in the 10+ Day range.. It's something to watch at least :popcorn:

[HurricaneJosh]

The ITCZ does have a little more action, I see-- but we're getting to that time of year where more and more any action is going to come from the rotting tail ends of troughs that dip down from the continent. Given this year's prevailing pattern plus general climatology, I wouldn't bother even looking at anything E of 60W if you're wanting a landfalling cyclone at this point.

[obxsnowman]

This season just up and vanished like a fart in the wind...

[rainstorm]

the atlantic looks interesting east of barbados.

http://www.atmos.was...latest.cgi?ir-e

[vinylfreak89]

wasn't much of a season to begin with... few storms during one MJO burp.... that about sums up the season. can't vanish if it wasn't really there to begin with.

[flwxwatcher45]

vinylfreak89, on 30 September 2009 - 07:18 PM, said:

wasn't much of a season to begin with... few storms during one MJO burp.... that about sums up the season. can't vanish if it wasn't really there to begin with.

It looks like one more MJO Burp on the way so maybe we will get something to pop in the Western Caribbean or the Gulf the next few weeks :scooter: