Atlantic Hurricane/Invest Thread 2012/2013

[summer blizzard]

Interesting goings on and the potential for some activity even.

 

1) In recent days ECWMF has put increasing definition in a cut-off low near the Caronlina's at day 5 now, GFS however has none of it although it's not an uncommon way to get genesis.

 

 

2) We should see a Kelvin wave increase the easterly trades from day 5 which could stimulate some development, the GFS18z of course opts to put on a show for us with a strong Tropical Storm headed for Cuba...

 

[summer blizzard]

Models today have dropped the Carolina's prospect and ECWMF gives us nothing of note today.

 

GFS however is pretty interesting...

 

1) We get a developing system east of Florida (seems to die) - this at day 11 so needs watching

 

 

 

2) At the same point as last night (day 14) the GFS once again develops a system in the western Carribean and heads north before dying in the Gulf of Mexico...

 

 

The reason i've shown you it today is because unlike yesterday it now has support from the GFS12z and far from killing it, the GFS has a strengthening hurricane in the Gulf...

 

 

 

3) Also worth noting that the GFS developed another storm in the mid-Atlantic...

 

[summer blizzard]

Two points today...

 

1) NHC forecast...

 

For the six-month hurricane season, which begins June 1, NOAA’s Atlantic Hurricane Season Outlook says there is a 70 percent likelihood of 13 to 20 named storms (winds of 39 mph or higher), of which 7 to 11 could become hurricanes (winds of 74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).

 

2) GFS once again attempts to develop a system in the Western Carribean starting at day 11, by day 16 it is a strengthening hurricane in the Gulf.

 

[BornFromTheVoid]

NOAA predicts active 2013 Atlantic hurricane season

 

Era of high activity for Atlantic hurricanes continues

 

 

In its 2013 Atlantic hurricane season outlook issued today, NOAA’s Climate Prediction Center is forecasting an active or extremely active season this year.

 

For the six-month hurricane season, which begins June 1, NOAA’s Atlantic Hurricane Season Outlook says there is a 70 percent likelihood of 13 to 20 named storms (winds of 39 mph or higher), of which 7 to 11 could become hurricanes (winds of 74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).

 

These ranges are well above the seasonal average of 12 named storms, 6 hurricanes and 3 major hurricanes.

 

 

The rest is here http://www.noaanews.noaa.gov/stories2013/20130523_hurricaneoutlook_atlantic.html

 

[summer blizzard]

GFS12z was bullish, had the system as a tropical depression at day 7.

 

CPC have noted it too, stating that conditions are expected to be favourable for development in the west Caribbean during early June.

[Iceberg]

Easy to underestimate this forecast imho, but NHC seem to be indicating a near perfect storm. Lots of GOM and Caribbean development as well as some re-curves from strong african waves. Cant remember a forecast as high as this from them.......

[Somerset Squall]

I can't either Iceberg. Just a 5% chance of a below average season. That's a pretty confident prediction.

[summer blizzard]

GFS12z today again had development starting in the high resolution time-frame

 

It then led to this...

 

. 

[johnholmes]

the NOAA and UK Met predictions are in about the same ball park so to speak but differ a little. Both go for an above average season

UK Met suggest the range 10-18 NOAA 13-20, UK suggest the most likely number is 9 with NOAA a somewhat higher figure. A bit confusing to me as they seem not to be using exactly the same criteria but that may just be me mis reading their published data.

Worth a Google for both outputs although I see the NOAA copy is already posted.

NOAA link

http://news.ca.msn.com/top-stories/2013-atlantic-hurricane-season-forecast-to-be-above-normal-possibly-extremely-active

UK Met link

http://www.metoffice.gov.uk/weather/tropicalcyclone/seasonal/northatlantic2013

Is it just me or do others find their links very slow to download?

Edited May 28, 2013 by johnholmes

[Iceberg]

Hadnt seen the latest meto forecast so thanks for that.

Meto seems very similar with both going for the same number of hurricanes ( 9 ).

 

Have to admit for me having a range forecast of 4-14 for hurricane makes the meto one rather wide. It would be difficult to get that forecast wrong !.

 

Meto seem to be going for a lower ACE score so may be not quite so many majors or long range fish/Re-curve canes which tend to add more to the ACE total.

[Iceberg]

RE development a chance of the GOC system developing in 5-6 days time maybe 10% atm, but worth watching day on day.

[Iceberg]

As well as the GOC possible development/GFS has been toying with sending an african wave quite quickly across the atlantic. Its got some very unusual height for this time of the year and avoids shear pretty much. Still 3 days until it starts any development but worth keeping an eye on imo.

[summer blizzard]

ECWMF has a strengthening TS at day 10 hitting the Gulf coast...

 

[mezzacyclone]

So on the 1st official day of the season at least somethings going off but generally speaking 90L is a mess?

NHC has a 10% chance of a TC out of the post-Barbara system but intense rainfall is projected with merging of developing thunderstorm activity over W carib to head for Western Cuba & eventual SW Fl but Jeff masters has it summarised in this afternoons blog. (at the bottom of his Tornado feature)

[summer blizzard]

Center has reorganized, now declared 91L.

 

General heading is for the west Florida coast.

 

 

General view is no significant development...

 

 

[mezzacyclone]

,,,and 91 looks a trifle more interesting than its predecessor?

[summer blizzard]

Some models are now more aggressive...

 

[summer blizzard]

http://www.bbc.co.uk/weather/feeds/22760382

 

BBC feature.

[Iceberg]

I like the GFS and ECM View on this, a spawled low pressure system crossing forida(no tropical charecterisitcs yet though) on Friday then up the east coast before it hits a cold intake to get some decent cyclogensis and shoots across the atlantic.

Then for us is moves up towards iceland etc and showers us with some moisture, warm air end of next week. 

Very believable and what I am going with as the likely outcome.

[Coast]

 

Weather Channel: Tampa most overdue hurricane city

 

Nearly a year ago, Bayshore Boulevard in South Tampa was completely under water and the Tampa Bay area experienced widespread damage from a tropical system that did not even reach hurricane status here. Tropical Storm Debby dumped up to 20 inches of rain on the region in late June 2012, flooded Pasco County streets for weeks, and left the region thankful but wondering what would have happened if she had developed into a full-blown hurricane. While we may have experienced a sense of relief but also complacency as we wonder if our luck will ever run out, a team of meteorologists at The Weather Channel and weather.com put out a serious warning for the Tampa Bay area.

 

A survey of meteorologists has determined that Tampa is the "most vulnerable and overdue" city for a direct hurricane hit. 

The meteorologists examined statistics from major coastal cities, and used 2012 criteria such as storm surge, evacuation time, population and the number of years since each city was hit hard by a hurricane. The experts included St. Petersburg, Sarasota and Clearwater in the area, and cites that combined population of about 4 million, evacuation time of 68 hours if hit by a Category 5 hurricane, and per-capita storm-surge loss of $17,813. They also said the area is 91 years overdue, with the last direct hit having come in 1921.

 

The National Hurricane Center calls for 13 to 20 named Atlantic storms, 7 to 11 that strengthen into hurricanes and 3 to 6 that become major hurricanes.

 

The other cities to make the Top 10:

[*]Naples

[*]Jacksonville

[*]Honolulu

[*]Houston

[*]Savannah, Ga.

[*]Mobile, Ala.

[*]Charleston, S.C.

[*]Key West

[*]Providence, R.I.

 

http://tbo.com/weather-channel-tampa-most-overdue-hurricane-city-20130604/

[Coast]

,,,and 91 looks a trifle more interesting than its predecessor?

 

Not sure it will amount to much?

 

 

Invest 91L may bring rain to Florida

Monday, June 3, 2013 at 9:15 by delstonejr

 

Three days into the new hurricane season and already we have a system to watch. The National Hurricane Center is calling it Invest 91L. It’s in the southern Gulf of Mexico, north of the Yucatan Channel. Right now it’s nothing more than a disorganized mass of cloudiness stretching from the Yucatan Peninsula and across to the southeast gulf. NHC gives it only a 20 percent chance of becoming a tropical cyclone over the next 48 hours, which is up from 10 percent over the weekend.

 

Moderate wind shear in the 20 kt to 30 kt range covers the gulf. This should inhibit significant development in the near term, although NHC, in its tropical weather discussion, says a surface low should form in the east-central gulf in the near future. One benefit of such a system could be rain showers. As the Panhandle is in its early summer dry period, a gift of tropical moisture could help keep our yards green, provided we don’t receive too much of a good thing! Models suggest a low will form and meander across the east gulf, moving ashore in the Big Bend area of Florida. None of the models are currently calling for an intense low. Good news for Floridians

 

http://delstonejr.blogs.nwfdailynews.com/10084/invest-91l-may-bring-rain-to-florida/

[summer blizzard]

Well its up to 50% with 36 hours to go and for the first time it actually looks quite pretty..

 

 

I'd say chances are that this makes cherry at the next update and is declared a Tropical Depression tomorrow morning (apparently has competing centers). 

[Somerset Squall]

Up now to 60% for 91L. Dry air is affecting 91L's western side and shear is also moderate. RECON are investigating the system at present. If it does get named it should remain fairly weak but high rainfall totals are a concern over Florida.

Edited June 5, 2013 by Somerset Squall

[mezzacyclone]

Up now to 60% for 91L. Dry air is affecting 91L's western side and shear is also moderate. RECON are investigating the system at present. If it does get named it should remain fairly weak but high rainfall totals are a concern over Florida.

Hasn`t shear waned a little from stronger earlier?

evidence of an LLC? 325miles SW of Tampa surrounding 25.14Lat -86.65Lon area on the current AF303 recon run, 50mph FL level winds,

enough for Andrea on the next adv SS?

[Somerset Squall]

Hasn`t shear waned a little from stronger earlier?

evidence of an LLC? 325miles SW of Tampa surrounding 25.14Lat -86.65Lon area on the current AF303 recon run, 50mph FL level winds,

enough for Andrea on the next adv SS?

It appears so Mezza lol.

 

Shear has eased a little but there is still about 20kts of shear over the system's centre and higher shear values further north, west of Florida. This should keep Andrea in check over the next day or so prior to landfall, barring any surprises of course.

Edited June 5, 2013 by Somerset Squall