WunderBlog Archive » Category 6™

Category 6 has moved! See the latest from Dr. Jeff Masters and Bob Henson here.

Jelawat brushing Taiwan; Nadine enters its 15th day of life

By: Dr. Jeff Masters, 2:50 PM GMT on September 27, 2012

Impressive Super Typhoon Jelawat remains just below Category 5 strength, as it heads north-northwest a few hundred miles east-southeast of Taiwan. The outer rain bands of the mighty typhoon are bringing heavy rains to the northern portion of the Philippines' Luzon Island, and will spread over eastern Taiwan later today, as seen on Taiwan radar. Wind shear remains a light 5 - 10 knots over Jelawat, and the typhoon is over very warm ocean waters of 29°C. These warm waters do not extend to as great depth as they did when Jelawat was east of the Philippines, though. Satellite loops show an impressive, well-organized typhoon with a 43 mile-wide eye, and a large, symmetric area of heavy thunderstorms with cold cloud tops.

The models are fairly unified on the track of Jelawat. The typhoon is expected to move north-northwest and then north, with the center passing about 150 miles to the east of Taiwan on Friday. Jelawat will likely pass very close to Okinawa, Japan as a Category 2 or 3 typhoon on Saturday, between 03 - 06 UTC. Jelawat could hit the main island of Honshu in Japan as a tropical storm on Sunday. Wind shear will begin increasing over Jelawat beginning on Friday morning, which should cause a steady weakening of the storm.


Figure 1. MODIS satellite image of Super Typhoon Jelawat taken at 1:03 am EDT Thursday, September 27, 2012. At the time, Jelawat had top winds of 155 mph, and an unusually large 43-mile diameter eye. Image credit: Navy Research Lab, Monterey.


Figure 2. Super Typhoon Jelawat's rain bands approaching Taiwan at 22:20 local time on September 27, 2012. Image credit: Central Weather Bureau, Taiwan.

Nadine enters its 15th day of life
The Energizer-bunny storm of 2012, Tropical Storm Nadine, has entered its 15th day of life as a tropical cyclone. Nadine may circle back to bother the Azores Islands on Tuesday, according to the latest run of the GFS model. That model shows Nadine getting caught up in a trough of low pressure by Wednesday and lifted to the northeast over colder waters, where it would likely die late next week. However, the 00Z run of the ECMWF model predicts that Nadine will miss the trough, and meander in the Central Atlantic for at least the next ten days. Nadine is already in ninth place for longest-lived named storm since 1950, according to a list compiled by Dr. Phil Klotzbach of Colorado State University:

1) Ginger, 1971: 21.25 named storm days
2) Carrie, 1957: 19.5 named storm days
3) Alberto, 2000: 19.25 named storm days
4) Bertha, 2008: 17 named storm days
5) Inga, 1969: 17 named storm days
6) Kyle, 202: 16.75 named storm days
7) Inez, 1966: 16.25 named storm days
8) Faith, 1966: 15.5 named storm days
9) Nadine, 2012: 15.0 named storm days

The all-time record is held by the San Ciriaco Hurricane of 1899, which had 28 named storm days.


Figure 2. MODIS satellite image of Tropical Storm Nadine taken at 10:15 am EDT Wednesday, September 26, 2012. At the time, Nadine had top winds of 50 mph. Image credit: NASA.

The rest of the Atlantic is quiet
None of the reliable computer models is predicting tropical cyclone development in the Atlantic through October 3. Most of the models predict that an extratropical storm will form in the Gulf of Mexico on Sunday, off the coast of Texas. Phase Space Diagrams from Florida State University show that this low is expected to remain non-tropical as it moves east-northeast across the Gulf, potentially coming ashore over the Florida Panhandle on Tuesday.

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.