Tropical Storm Krovanh

[Somerset Squall]

Invest 90W continued to rapidly organise overnight, got upgraded to a tropical depression (12W), and now has been upgraded to a 40kt tropical storm, named Krovanh. Krovanh is maintaining some very vigorous convection over the strong LLC and is developing good banding features in the southeastern quadrant of the storm. Krovanh is currently moving generally northwards towards Japan, along the western periphery of a ridge to the east. This ridge is exected to slowly build north of Krovanh over the next day or two which should turn the storm to the west before it reaches Japan. However, the timing of this turn is not certain and needs to be watched. Krovanh should continue to strengthen in low shear and war sea temperatures, the only limiting factors possibly being land interaction with Japan. JTWC forecast Krovanh to become a typhoon.

[Somerset Squall]

In an environment of low shear, warm waters and excellent radial outflow, Krovanh has continued to intensify. Winds have increased to 50kts. Krovanh is moving northwestwards along the southwestern periphery of a ridge to the northeast. This ridge is no longer expected to build westwards and instead will remain where it is. This has a significant impact on future track. Krovanh is now expected to make landfall in Japan then head northeastwards whilst turning extratropical, along the northwestern periphery of the ridge. Cooler waters and higher shear will induce the extratropical transition.

[Cookie]

this is going to take an interesting track

[Somerset Squall]

A concerning one too; Etau a couple weeks ago caused numrous deaths and damage and it was only half the strength Krovanh is progged to be. Japan need to be very wary of this one.

[Somerset Squall]

Krovanh is gradually intensifying as it heads north-northwestwards towards Japan, and is now at 55kts. Deep, convective banding is wrapping healthily around the well defined LLC. Low shear, warm sea temps and good outflow will persist for the next 24hrs which should allow Krovanh to become a typhoon as it grazes Eastern Japan. Thereafter, land interaction, followed by a passage over colder waters and higher shear should cause weakening then extratropical transition. This storm has the potential to cause flash flooding and mudslides, so still needs to be watched.

[Somerset Squall]

Krovanh peaked at 60kts, just below typhoon strength. Shear is now increasing, and although still well organised, Krovanh has weakened to 55kts. Krovanh will soon brush Japan and a fairly strong tropical storm, where it could bring light damage but more importantly, potential flooding. Krovanh will then race northeastwards, as it rounds the periphery of the steering ridge, and turn extratropical over colder waters. It is likely to become an intense extratropical cyclone in the open waters of the northern Pacific.

[Somerset Squall]

Krovanh pounding southeastern Japan as a 55kt tropical storm:

http://www.bloomberg.com/apps/news?pid=20602085&sid=aNLSm9QLHtVA

[Cookie]

correct me if im wrong I think it just made typhoon statues before landfall

[Somerset Squall]

Well, oddly that graph says it did, though I can't find anything in JTWC advisories or JMA advisories saying it did and as far as I am aware Krovanh peaked at 60kts. Will look into it though, must admit I wasn't avidly following this one!

Anyway, Krovanh has become extratropical. I haven't seen any reports about damage as yet so hopefully that is minimal.

Edited August 31, 2009 by Somerset Squall

[Cookie]

spotted the graph and wanted you're thoughts, let you do a bit of digging and report back weather you find anything or not mate.

[Somerset Squall]

Nope, can't find anything supporting more than 60kts. Well spotted though, could be an error in the graph. Of course, when the best track and storm summary is released later in the year it may possibly be upgraded (Krovanh did have signs of an eye at one point), and example was Jangmi from last year, operationally was classed as a 135kt cat 4 and was upgraded to a 145kt cat 5 in post storm analysis. For now, it has been classified as a tropical storm of 60kts at peak.

[Cookie]

thanks mate for looking