Super Typhoon Nida

[Somerset Squall]

TD 26W has formed from invest 94W. Initial intensity is 30kts. The depression has formed 6 degrees north of the equator which makes it the southernmost tropical cyclone formation for the Western Pacific this year. 26W's location so far south means it has plenty of warm water to traverse. In addition, though shear is moderate at the moment, this is expected to ease. These two factors should see 26W become a typhoon over the next several days.

Steering currents are currently weak and conflicting, mainly because 26W is still involved with a monsoon trough. As 26W strengthens and lifts out of the monsoon trough, a subtropical ridge to the northeast should enforce a northwesterly motion. This should take 26W southwest of the island of Saipan, though track deviations may occur, and the outer bands are still, at this stage, expected to bring heavy rains to the island.

[Somerset Squall]

26W has slowly consolidated over the last 36hrs and has become Tropical Storm Nida, with intensity at 35kts. The storm looks impressive on satellite imagery with spiral banding surrounding a developing central dense overcast. With the favourable environment of low shear, warm sea temps and good outflow, strengthening is likely. In fact, Nida's current impressive structure suggests that this one could spin up quickly. After meandering in a weak steering environment over the last 36hrs, Nida is now being steered to the northwest along the southwestern periphery of a subtropical ridge to the northeast.

[Somerset Squall]

Nida continues to intensify, and intensity is now at 50kts. Nida has maintained impressive spiral banding, and the central dense overcast is now fully formed. With this satellite presentation, it seems likely Nida will become a typhoon very soon. JTWC are expecting Nida to be a 105kt cat 3 by 120hrs- a fair assessment, but is always the case, don't be surprised to see Nida go higher than this.

[Cookie]

thanks for the updates

[Somerset Squall]

Nida has become a cat 1 typhoon, with intensity now at 65kts. Good radial outflow, warm sea temps and low shear will facilitate further intensification as Nida continues to push northwestwards. It appears that Nida will eventually approach a weakness in the ride and re-curve northeast into higher shear and cooler waters. Until then however, Nida has a favourable environment in which to strengthen.

[Somerset Squall]

Update: Nida's intensity has just been bumped up to 75kts by JTWC. Eye is clearing out, a good sign of a maturing typhoon.

[Somerset Squall]

Nida has bombed overnight, and is now a 125kt cat 4 typhoon. Very warm waters, low shear and excellent outflow have facilitated this rapid strengthening. The eye is very small and well defined and is surrounded by a near perfect central dense overcast and good spiral banding. Nida is expected to pass over even warmer waters over the next 24hrs, so it seems likely Nida will become the third cat 5 of the season. Nida, thankfully, looks like it will miss land apart from the small island chain of the Marianas who are used to frequent typhoons. A re-curve scenario as the ridge to the northeast weakens is still the favoured solution by JTWC.

[Somerset Squall]

Woah, look at the lastest dvorak estimates, approaching 8! What a monster! Defintely cat 5 next advisory, and maybe the strongest TC of the year if this verifies!!

----- Current Analysis -----

Date : 25 NOV 2009 Time : 080100 UTC

Lat : 12:07:09 N Lon : 142:38:57 E

CI# /Pressure/ Vmax

7.7 / 874.3mb/161.0kt

[Somerset Squall]

[Somerset Squall]

Nida has become the strongest typhoon of the 2009 West Pacific season though is 2nd strongest behind Rick worldwide. Intensity has increased to a whopping 150kts, making Nida a category 5 Super Typhoon. The eye has shrunk and is excellently defined. Nida has the oppurtunity to get a little stronger, don't be surprised to see the intensity approaching 160kts later. What a beast!!

[Cookie]

sorry sorry for the lack of updates what a beast what a monster.

UW - CIMSS

ADVANCED DVORAK TECHNIQUE

ADT-Version 8.1.1

Tropical Cyclone Intensity Algorithm

----- Current Analysis -----

Date : 25 NOV 2009 Time : 183200 UTC

Lat : 13:48:57 N Lon : 141:13:00 E

CI# /Pressure/ Vmax

7.8 / 869.6mb/164.0kt

Final T# Adj T# Raw T#

7.7 7.7 7.7

Latitude bias adjustment to MSLP : +3.2mb

Estimated radius of max. wind based on IR : 20 km

Center Temp : +18.6C Cloud Region Temp : -80.2C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

Ocean Basin : WEST PACIFIC

Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : NO LIMIT

Weakening Flag : ON

Rapid Dissipation Flag : OFF

[Somerset Squall]

Nida is now the strongest tropical cyclone of 2009, surpassing Rick. Intensity is 160kts, and storms this intense are not all that common. Neither is a consistant raw dvorak reading of near 8. The last storm to display readings near 8 was Cyclone Monica near Australia in 2006, which is even rumoured to possibly be the strongest TC of all time (though Typhoon Tip holds the official record). A very impressive storm, especially for November. El Nino has boosted the number of cat 5's this year in the West Pac after the lull of storms reaching cat 5 status over the last couple years. And the rate of intensification was nothing short of amazing- cat 1 to cat 5 in 18hrs. And what is quite amazing too is a number of storms in the West and East Pac have pulled off rapid strengthening this year. Shows what waters a couple degrees above average and low shear on the whole can really do.

Nida has more than likely peaked. The north-northwestward motion will continue for at least the next 48hrs before the storm re-curves northeast into higher shear and cooler waters which will eventually initiate a more firm weakening trend.

[Cookie]

yup 18 hrs is mental really is,

do you think nida might have got the record? the all time record

[Somerset Squall]

Can't be sure. We'll have to wait for the final report which will be issued next year.

Nida has weakened to 130kts as the super typhoon moves into higher lattitudes over cooler waters and slowly increasing shear. The eye remains well defined but the convective pattern is not symmetrical anymore due to shear. Further steady weakening is forecast on the northerly track, before more aggressive weakening takes place as Nida acclerates northeastwards into the mid-lattitude westerlies. After peaking at 160kts, Nida is likely to become a formiddable extratropical storm in around 4-5 days time.

[Somerset Squall]

Nida has unexpectedly re-strengthened to 150kts, and thus is now a cat 5 again. Nida has completed an eyewall replacement cycle, which was probably more of a reason for the weakening last night. A large, well defined eye lies in the centre of the more symmetrical CDO. Weakening is still expected, particularly beyond 48hrs as shear dramactically increases and water temps rapidly shelves off.

[Cookie]

still looking really good and some uncertainty re the track at the moment.

[Supercell]

Possibly the most intense tropical cyclone of all time ? ... I would love to know. It's just a shame the information on readings from the Pacific is somewhat scarce in comparison to the Atlantic.

Those wind speeds are incredible. I would love to know the lowest pressure reading. Although I understand that this is difficult to ascertain as the JTWC don't use hurricane-style hunter planes for their recording purposes ?

[Paranoid]

I saw something about the official lowest pressure of Nida being 905mbar, but i think i saw a Dvorak estimate somewhere in the 870's? If someone can confirm i'm not just talking rubbish here it'd be handy

[Cookie]

this will help mate

UW - CIMSS

ADVANCED DVORAK TECHNIQUE

ADT-Version 8.1.1

Tropical Cyclone Intensity Algorithm

----- Current Analysis -----

Date : 25 NOV 2009 Time : 183200 UTC

Lat : 13:48:57 N Lon : 141:13:00 E

CI# /Pressure/ Vmax

7.8 / 869.6mb/164.0kt

Final T# Adj T# Raw T#

7.7 7.7 7.7

Latitude bias adjustment to MSLP : +3.2mb

Estimated radius of max. wind based on IR : 20 km

Center Temp : +18.6C Cloud Region Temp : -80.2C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

Ocean Basin : WEST PACIFIC

Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : NO LIMIT

Weakening Flag : ON

Rapid Dissipation Flag : OFF

from either thursday or weds

Edited November 28, 2009 by cookie

[Paranoid]

Wow, 869.6?. The record lowest pressure is 870mbar from Typhoon Tip in 1979, as that was measured by aircraft rather than estimated by satellites. If that 869.6 reading was official it could well be the most intense tropical cyclone recorded, though i don't know if 870 is a rounded value. I think they'll take 905mbar as being the official value for Nida, as Cyclone Monica recorded a similar value on the satellite estimates a few years back.

[Cookie]

[Cookie]

[Somerset Squall]

Interesting discussion regarding whether Nida was the most intense cyclone on record, those dvorak readings/numbers where highly unusual and as I said earlier, a raw reading consistantly approaching 8 is very rare and was last seen with Cyclone Monica in 2006. I guess we'll never truly know, though post season analysis will shed some more light on it.

The forecast track, as Cookie said, has been uncertain. Originally, Nida was forecast to accelerate northeastwards and undergo ET. However, Nida has stalled as it has become trapped between two ridges, one to the west and one to the east. A slow northward drift will be the net motion of this competitive steering environment. High shear is already having a negative effect on Nida (intensity is now a reduced 120kts), and fast weakening is expected before eventual full dissipation and the shear tears the circulation apart. ET now appears unlikely.

[Cookie]

not much movement today and appears to have taken a gulp of dry air

[Somerset Squall]

I agree Cookie. Additionally, the stalling is causing upwelling of cold water further weakening Nida. Shear is steadily increasing too. It's difficult to see how Nida can hold out much more in this hostile environment- however, as it was such a strong storm to begin with then it will take it's time to wind down. Intensity has only lowered to 100kts this morning, making Nida a cat 3.

Steering currents remain very weak this morning, with ridges to the west and east still competing, cancelling any steering flow. Eventually, the western ridge will begin to weaken slightly and the eastern ridge will begin to re-orientate to the north, which will enforce a slow westward motion. Track speeds will remain slow as the western ridge is not expected to dissapear completely. JTWC still mention that Nida could instead accelerate northeastwards. This will only happen if the western ridge weakens aggressively and the eastern ridge remains in place- which would cause Nida to round the the northwestern periphery of the this ridge and move northeastwards as a result. This second scenario is considered more unlikely but cannot be fully discounted.

If Nida moves northeastwards, then it would transition into an extratropical storm. As it stands, the more westward solution to the track (favoured scenario) will lead to full dissipation as the waters are still farily warm but the shear/dry air will continue to erode convection and ultimately destroy the circulation of Nida.

Edited November 30, 2009 by Somerset Squall