Worldwide Tropical Update: 23 October

[senorpepr]

The 23/18Z update is posted featuring...

* Typhoon (Cat 3) Nock-ten (28W)

Enjoy and feel free to reply back with comments!
http://tropicalupdates.nhcwx.com/

[senorpepr]

Besides our featured tropical cyclone(s), we're monitoring the following invest system(s).

Invest 99L
35.6N 67.3W (270mi NW of Hamilton, Bermuda)
45 mph; 997 mb / 29.44”
Herbert-Poteat estimates: ST1.5/1.5
99L is a new invest located in the Atlantic. Currently, this system is a deep occluded system or extratropical. The cold front associated with this system is forecast to undergo frontolysis, thus losing some of its baroclinic punch. Since this system is located over fairly warm waters, if 99L loses it’s frontal features, it may become a subtropical system. Current model guidance shows this system reaching hurricane strength, but it should be noted that model guidance in terms of strength should be looked at as suspect. In any event, it will need to be monitored. Finally, it should be pointed out that although NRL lists 99L as a 45 mph system (40kt), according to the Satellite Service Division, the Herbert-Poteat estimate is ST1.5. A 45mph system would typically bear a ST2.5 reading.

Invest 93S
5.4S 62.4E (475mi SE of Victoria, Seychelles)
15 mph; 1006 mb / 29.71”
Dvorak estimates: Too weak
92S, from yesterday, has weakened and a nearby disturbance, which was fueled by 92S has strengthened slightly. Therefore, 92S has been dropped and 93S has been initiated. Regardless to the recent activity, Quikscat shows a poorly defined low-level circulation. Additionally, convection is very limited. Shear aloft has increased slightly and the overall potential for development remains low. The JTWC lists a poor chance for development whereas Meteo-France lists none.

Go to http://www.nrlmry.navy.mil/tc_pages/tc_home.html for the latest satellite imagery.

[Anonymous]

Hey Mike, I think this will develop. You? I mean, not what time, how strong, but..Do you think this will be anything?

[senorpepr]

Hey Mike, I think this will develop. You? I mean, not what time, how strong, but..Do you think this will be anything?

Well, here's my take on 99L. Some people believe, based on the inital intensity of 40kt, that this is already STS Otto. I don't agree at all. This system is still very baroclinic, as I mentioned in the above post.

However, over the next few days I can see some development. I'm not completely set on it becoming a subtropical cyclone, but the odds, IMO, are leaning toward it.

Shear is limited over the system itself, but it is VERY strong to 99L's southeast. Some of the models take it in that direction so if that holds true -- no development.

Also, another deep system is moving across the eastern third of the US. This could also hinder subtropical development if it gets too close.

Another thing is the model guidance shows this system reaching hurricane status. I highly doubt that. Conditions, IMO, aren't that favorable.

With all that said, I do believe there is a possibility for subtropical development in the long run -- over the next few days. We shall see.