I honestly don't know why invest 97L was discontinued, it looks like tropical development is imminent.

Dolly has formed in the Gulf of Mexico, but blink and you've missed her!

http://www.weather.com/weather/hurricanecentral/tracker

No immediate prospect of Atlantic development

I've been waiting for something interesting in the actual tropics for a long time now...

Cristobal was largely in the subtropics and Dolly, while in the tropics, just isn't up to much other than developing deep convection and some reasonably strong winds - just another in a long line of moderate tropical storms that I've observed over the years.

GFS is suggesting one or two systems forming near the Cape Verde Islands within the next week, which could be of some interest. Unfortunately, it persistently showed something strong developing around there late last week across a dozen or so runs, which then never materialised (the wave just fell apart), reducing confidence in the model's projections even in the 5-7 day range.

But, to look on the brighter side, GFS spotted Cristobal at a ten-day range - and now the 12z chart has a developed hurricane stalled in mid-Atlantic from Wed 17Sept. One to keep an eye open for to find out if it verifies.

GFS has abandoned this one in today's charts but has another go at T +384 - GFS is beginning to look like PWS in this respect, hoping that one or two spectacular successes will outweigh the disappointments.

The latest Invest off Africa (90-L) has been given only 10% chance of surviving.

That invest (90L) has a good amount of spin though, and even has some reasonable convection and an organised moisture field. There are some over the other side of the pond who reckon the development chances should be much higher than 10%, and in fact I reckon it could well be a tropical depression already.

It will have to battle dry air subsiding from above in the near future, then a bout of rather high wind shear, so life doesn't look easy for it - but the well defined circulation means it could sneak into a more favourable environment further west, so it needs watching for that.

Now T +384 has become T +360, the 06Z has it centred as a major extra-tropical storm in the Irish Sea just off Belfast! Don't worry, it may never happen

http://www.theweatheroutlook.com/twodata/datmdlout.aspx

Its been such a 'dull' season so far, even 2013 had more interest than this year.

91-L now appearing and given 60% chance of survival. Even though it still has the same hazards (dry Saharan air, wind shear) as previous Invests, it looks more organised at an early stage. Early predictions are that if it does survive it will stay offshore, recurve and visit the North Atlantic. If this is the one predicted on the GFS (see post above), the Irish Sea scenario has been shelved in favour of a visit to the Faeroes.

We now have tropical storm Edouard, likely to develop into a hurricane in mid-Atlantic

http://www.weather.com/news/weather-hurricanes/tropical-storm-edouard-atlantic-20140911

(Pity you can't fast-forward through the bit about the thunderstorms in Florida, but be patient)

http://www.tropicaltidbits.com/analysis/cdas-sflux_sst_atl_1.png

Just look at those SSTs east of Florida... some of those are in the sub-tropics believe it or not!

Edouard is going to be marching right into that region over the coming days.

Not only this, but it looks like the position of the jet stream will act to create a strong outflow channel going NE (upper level winds transporting lifted air in that direction), while at the same time an upper level low over the Bahamas looks to create a channel going W - which means that the air above Eduoard will be diverging at an exceptional rate.

With so much air being taken away from above Eduoard, the vertical transport of air involved in deep convection should be enhanced substantially, and this could allow Ed to have a run at major hurricane status while tracking across those 28-30*C waters.

Looking further ahead, both GFS and ECM track Ed towards the Azores. Clearly, SSTs drop below the 26*C threshold for tropical cyclone development in that area, but it's possible for a cyclone to hold together over 21-24*C waters for a little while, maybe a day at a stretch. Something for them to keep an eye on!

Eduoard is just the right sort of 'cane to enjoy observing - nicely organised, steadily strengthening and not impacting land areas directly:

http://www.ssd.noaa.gov/PS/TROP/floaters/06L/imagery/vis-animated.gif

Having said that, the latest tracks are a bit loopy and do threaten the Azores with a possibly still tropical - or hybrid - system:

http://www.emc.ncep.noaa.gov/gmb/tpm/emchurr/tcgen/tcgif/track.aeperts.2014091412.tc_atl_ll.single.png

If only Odile could have been so innocent:

http://www.ssd.noaa.gov/PS/TROP/floaters/15E/imagery/vis-animated.gif

A category 4 monster, with the appearance of a West Pacific typhoon, bearing down on the Baja Peninsula.

This could be bad for those that live there - which is thankfully not a large population. Thoughts are with those in Odile's path.

I wouldn't be suprised if it is reborn though as another tropical cyclone, it moves back south again into a warm and low sheer environment. Very wierd track.

A weird track, following exactly that finger of land (Cabo San Lucas) which sticks out into Baja California - and indeed much damage as expected. Torrential rain and flash floods expected for south-west USA (but at least it might help to recharge the aquifers)

http://www.weather.com/news/weather-hurricanes/tropical-storm-hurricane-odile-pacific-mexico-20140910

http://i.imgur.com/lo6fx6d.jpg

Eduoard still has an eye feature and good structure despite being over SSTs lower than 26*C.

Goes to show that cyclones don't always follow the rules.

The cyclone has contributed more than 12.2 units of accumulated cyclone energy (ACE) to the 2014 Atlantic season, which is more than achieved by any Atlantic cyclone in 2013.

A full two weeks since the last Atlantic tropical storm/hurricane, and still no prospect of any in the near future (though the Pacific is having another belting, with both Japan and the Baja California peninsula being threatened this coming week).

So, there have been a number of factors which have suppressed development, from dry air to high-level wind shear, but the sun has still been pouring energy into the region all summer. A (possibly naive) question arises: where is all the energy going, if not into hurricane formation?

• staying where it is, so that any later-developing hurricanes in the Gulf will have more energy to draw on and be more powerful - or if discouraging factors continue, a warmer and wetter winter for the southern US


• or being exported e.g. via the Gulf Stream into the North Atlantic with the prospect of more cyclogenesis there this winter i.e. a winter like 2013-14 again


• or gently dissipated by radiation into space


• or are hurricanes essentially a local phenomenon, for all their fury contributing little to the tropical energy budget?

In theory a lack of tropical activity (not just cyclones but tropical convection in general as seen this season) should leave an excess of ocean heat content in the tropics, which, in the continued absence of tropical convection, is then capable of generating higher than normal atmospheric temperatures which could lead to enhanced cyclogenesis in the subtropics and North Atlantic.

Such may have played a factor last winter, but that was primarily driven by anomalously high rainfall in Indonesia causing an unusually large, locked-in jet configuration.

This time around, if we saw, for example, a persistent anticyclone over the easternmost reaches of the U.S. instead of cyclones, then the main instability region would be in the central North Atlantic, and the potential for steep temperature gradients and an exceptionally strong jet stream affecting the UK lower. This is because, across the latitudes important to the UK, there are no large areas of land in the central North Atlantic, and that is required to produce very low temperatures on the cold side of the boundary to contrast with temperatures on the warm side of the boundary and supercharge the jet like we saw in 2013/14. It could still be a fair bit stronger than 'normal', though.

Perhaps the biggest difference would be a far greater chance of seeing storms making it to the east of the UK and delivering back-end northerlies, with the potential for something more prolonged if some blocking highs got in on the act.

Why have I gone into this theoretical evolution in such detail? Well...

http://www.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd3/glbz700MonInd3.gif

http://www.cpc.ncep.noaa.gov/products/people/wwang/cfsv2fcst/imagesInd3/glbz700MonInd4.gif

The projections for January have actually been trending towards that anomalously high pressure over Greenland over the past week or so.

This is just one model of course, and there's no denying how hopelessly wide of the mark many long range projections have turned out to be over the past few years - though there have been some remarkable successes every now and then too (most notably CFS spotting March 2013 several months in advance and sticking with that for most of the way afterward, apart from a week-long venture in January I think it was).

Interesting; but as with all things weather-related, not as simple as at first sight.

Many thanks

Excellent photo of Typhoon Vongfang from Reid Wiseman on board the ISS:

https://twitter.com/astro_reid/status/520165368275697664

At last, we have another named storm in the Atlantic, Fay

http://www.accuweather.com/en/weather-news/tropical-atlantic-may-spring-t/35419260

though it's not forecast to develop much and indeed its main effect could well be to push a lot of moist air in our direction rather than affect the US

What do they know eh... Fay's made it to hurricane status - though only just - and this comes after bringing 65mph sustained winds to Bermuda. Not bad going for what was originally a cold-core upper level low working down to the surface.

Gonzalo has also formed just east of the Caribbean, and appears destined to make a brief visit to that sea before exiting via Puerto Rico or thereabouts, possible while attaining hurricane status. In fact the NHC forecast calls for a category 2 hurricane in 5 days time, and also mentions that rapid intensification is a distinct possibility due to the storm being very compact and in an environment of low wind shear and warm SSTs - dry air in the surrounding environment is the only impediment, as has been the case for all storms in the tropical Atlantic so far this season.

The proportion of named storms hitting hurricane status this season is a bit uncanny, even though the actual numbers aren't very high.

If Gonzalo makes hurricane status, the figures will be 6 out of 7 if you don't count depressions (which only get numbers), otherwise 6 out of 8.

http://icons.wunderground.com/data/wximagenew/k/KEEPEROFTHEGATE/4214.gif

I didn't realise nobody had updated here on Gonzalo!

This 145 mph major hurricane is headed right for Bermuda and the eye looks to track just to the west of the island, which if it verifies will place it right under the strongest portion of the storm - the front-right quadrant.

While maximum winds are likely to drop to some extent before this close pass or landfall, the storm has such a well organised structure that it will probably put up a strong fight - so Bermuda may well be facing up to a category 3 or 4 'cane.

It could be the strongest impacting or landfalling 'cane in recorded history for the island.

Gonzalo is the strongest - and first category 4 - hurricane since October 2nd 2011.

For a time there was just a hint of rare category 5 status, which would have been the first for 7 years, but for that you need absolutely perfect conditions in the Atlantic, and really the surrounding atmosphere is just a little too dry on this occasion.

Thoughts are with those in Bermuda who are in for an exceptionally rough night Friday-Saturday. They have strong building codes so will fare better than most places would, but past major 'cane impacts have featured some considerable damage so the threat level is substantial.

And heading to our neck of woods (in some shape or form) eventually. SE Newfoundland also looks like taking a hit from this.

Hurricane Gonzalo starting to on the Bermuda rainfall radar

http://andrew.rsmas.miami.edu/bmcnoldy/tropics/gonzalo14/Gonzalo_17Oct14_bermuda_long.gif