Super Typhoon Lupit

[Somerset Squall]

Lupit has turned back towards the west today. A the same time, the typhoon has weakened, due to an influx of cold dry air into the western quadrant of the storm. Intensity has been reduced to 115kts. Strong ridging to the north may even build to the northwest of Lupit, forcing a southwestward motion over the next day or so. It appears that even the fact that Lupit has gained more lattitude than previously forecast will not stop it making landfall in Luzon. Further weakening will occur as Lupit crosses Luzon, but re-intensification is possible once the typhoon emerges in the south China sea.

Edited October 19, 2009 by Somerset Squall

[Somerset Squall]

Lupit has weakened further as the dry air continues to eat away at the convectional coverage of the LLC. Lupit is still maintaining some deep convection over the centre and still has a cloud obscured eye. Intensity has been reduced to 105kts. Further weakening is likely overnight as dry ait continues to adversely affect Lupit. Weakening to a cat 2 is forecast to occur soon. In about 12-24hrs time, the tropical moisture is expected to increase which may allow some slight re-intensification before landfall in Luzon. Luzon will obviously weaken Lupit quite a lot as it traverses the ragged terrain. When Lupit emerges in the south China sea, the typhoon is still likely to strengthen again as shear is low in the area and sea temperatures are very warm.

[Cookie]

thanks for the updates

[Cookie]

[Somerset Squall]

Lupit has weakened to 95kts, but conditions are more favourable again with the air becoming moister once more, shear lessening and outflow improving. Based on this, I expect Lupit to re-strengthen today, and would guess the typhoon will make landfall in norther Luzon, Philippines, as a 105-110kt system. The forecast remains the same thereafter; Lupit has the chance to re-intensify in the south China Sea which is not good news at all. Not to mention the further pain the typhoon is going to cause the Philippines.

[Cookie]

has gone through eye wall replacement by the looks of things

[Somerset Squall]

has gone through eye wall replacement by the looks of things

Certainly seems so Cookie, and this has caused further weakening to 85kts. However, looking at latest satellite imagery, the eye appears to be re-emerging from the central dense overcast. This could be a sign that the expected re-intensification is finally starting. JTWC are expecting Lupit to make landfall as a 100kt cat 3 on Luzon, though an intensity a touch higher than this is still possible as poleward outflow has improved greatly over the past 6hrs.

Track forecast is not so clear cut now, and the models actually diverge significantly. JMA are forecasting Lupit to recurve northeastwards and miss Luzon as the ridge to the north gets broken down by a passing trough. JTWC mention this as a possibilty but still favour the scenario of the ridge remaining strong continuing the westward track. The track forecast by JTWC has shifted northward in reponse to the possible recurve scenario and JTWC say that further shifts are likely as the models continue to disagree.

[Cookie]

video from Jim Edds

http://www.weatherzine.net/blog/2009/10/21/people-ready-for-typhoon-lupit-in-aparri-philippines/

and some pics from extreme storms.com

http://www.extremestorms.com/typhoon_lupit.htm

Edited October 21, 2009 by cookie

[Cookie]

getting busy out their.

[Somerset Squall]

Contrary to previous forecasts, Lupit has continued to weaken and intensity is now at 65kts. Dry air seems to be once again the problem, which is penetrating the inner core of Lupit. Lupit lacks sufficient outflow to mix out the dry air, so further weakening is expected. As Lupit approaches Luzon, land interaction will further add to the weakening. The storm will still be unleashing flooding rains to the country however.

Unfortunately, I envisage another situation similar to Parma. Steering currents are expected to completely collapse with ridges to the east and west of Lupit cancelling the steering flow. This means Lupit could well loiter off the north coast of Luzon for 3-4 days at least. Although Lupit may not hang around quite as long as Parma, the stalling forecast will probably bring much more rain to already saturated ground. One caveat to the forecast that JTWC mention is a trough swinging by in about 48hrs time has the potential to lift Lupit out of the weak steering environment and send the storm northeastwards into the mid-lattitude westerlies, where extratropical transition will begin. However, the trough's interaction with Lupit is still poorly handled by the models so it is unclear just which scenario will play out.

[Cookie]

thanks for the updates

[Somerset Squall]

Lupit has been downgraded to a tropical storm, and intensity has fallen to 55kts. Further slow weakening is expected over the coming few days due to the dry air surrounding the storm.

Track forecasts now favour Lupit moving towards the northeast, and this is now forecast by both JTWC and JMA. Of the two steering ridges competing east and west of Lupit, the eastern ridge has become more dominant which explains why a track to the northeast seems more likely. In fact, the turn has already begun. However, the ridge to the west will still have some influence, so track speeds will continue to be slow. Good news though overall as Lupit will be moving away from the Philippines very soon.

[Cookie]

very complicated track

[Somerset Squall]

very complicated track

Indeed Cookie! The southwestward motion indicated at the end of the forecast period is because Lupit will become shallower and will be steered by low level northeasterly flow.

Intensity has remained at 55kts. Slow weakening is expected as shear joins the dry air to kill the storm. Lupit may take another 5 days to dissipate however as the system moves generally northeastwards towards Japan (as the track map shows however, it probably won't make it that far).

[Cookie]

seems to have re strengthened a little

[Cookie]

[Somerset Squall]

Quite right Cookie, Lupit looks on the verge of typhoon strength again, and intensity has increased to 60kts. An eye feature is visable in satellite imagery with a solid ring of convection surrounding it. Despite increasing shear and falling sea temps, poleward outflow has sustained Lupit in the otherwise unfavourabke environment. Lupit is no longer expected to dissipate and is instead expected to transition into a powerful extratropical storm on the continued northeasterly track.

[Cookie]

[Cookie]

On its way out

[Cookie]

final warning issued

Final Warning by JTWC

WTPN31 PGTW 260300

MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//

SUBJ/TROPICAL CYCLONE WARNING//

RMKS/

1. TROPICAL STORM 22W (LUPIT) WARNING NR 049

02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC

MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE

WIND RADII VALID OVER OPEN WATER ONLY

---

WARNING POSITION:

260000Z --- NEAR 27.5N 133.6E

MOVEMENT PAST SIX HOURS - 065 DEGREES AT 19 KTS

POSITION ACCURATE TO WITHIN 040 NM

POSITION BASED ON CENTER LOCATED BY SATELLITE

PRESENT WIND DISTRIBUTION:

MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT

WIND RADII VALID OVER OPEN WATER ONLY

BECOMING EXTRATROPICAL

RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT

115 NM SOUTHEAST QUADRANT

095 NM SOUTHWEST QUADRANT

085 NM NORTHWEST QUADRANT

REPEAT POSIT: 27.5N 133.6E

---

FORECASTS:

12 HRS, VALID AT:

261200Z --- 31.3N 138.4E

MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT

WIND RADII VALID OVER OPEN WATER ONLY

EXTRATROPICAL

VECTOR TO 24 HR POSIT: 040 DEG/ 39 KTS

---

24 HRS, VALID AT:

270000Z --- 37.1N 144.6E

MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT

WIND RADII VALID OVER OPEN WATER ONLY

EXTRATROPICAL

---

REMARKS:

260300Z POSITION NEAR 28.4N 134.8E.

TROPICAL STORM (TS) 22W (LUPIT), LOCATED APPROXIMATELY 580 NM

SOUTHWEST OF TOKYO, JAPAN, HAS TRACKED NORTHEASTWARD AT 18 KNOTS

OVER THE PAST SIX HOURS. TS LUPIT HAS STARTED TO SUCCUMB TO THE

ADVERSE EFFECTS OF HIGH VERTICAL WIND SHEAR. ANIMATED MULTI-SPECTRAL

IMAGERY SHOWS ALL DEEP CONVECTION HAS DISSIPATED WHILE THE

SIGNIFICANT PRECIPITATION HAS SHIFTED ENTIRELY TO THE NORTHEAST OF

THE LOW LEVEL CIRCULATION CENTER (LLCC). THE LLCC IS NOW EXPOSED,

THOUGH A 252118Z QUIKSCAT PASS REVEALS THAT IT IS ALSO STILL WELL-

DEVELOPED. THE REMNANTS OF TS LUPIT WILL CONTINUE TO HOLD TOGETHER

AS THE SYSTEM GATHERS JET SUPPORT AND COMPLETES EXTRATROPICAL

TRANSITION OVER THE NEXT 12 HOURS. THIS IS THE FINAL WARNING ON THIS

SYSTEM BY THE JOINT TYPHOON WARNING CENTER (NAVMARFCSTCEN). THE

SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM

SIGNIFICANT WAVE HEIGHT AT 260000Z IS 21 FEET. REFER TO TROPICAL

CYCLONE 23W (TWENTYTHREE) WARNINGS (WTPN32 PGTW) FOR SIX-HOURLY

UPDATES.//

NNNN

[Somerset Squall]

In post storm analysis, Lupit has been upgraded to cat 5, which makes the total number of cat 5's in the Western Pacific in 2009 rise to four ( the others being Choi-wan, Melor and Nida).

Edited March 19, 2010 by Somerset Squall

[Cookie]

thanks for passing that on somerset

[Somerset Squall]

No probs Cookie.

Also interesting to note that the last time a typhoon was named Lupit that was also a cat 5, in 2003. The same is true for Nida.

Also, Morakot, Parma and Ketsana have been retired- not really surprising given the devestation each caused.

[Cookie]

speaking of names retired.

I presume the west pacfic gets the most number of names retired overall?

[Somerset Squall]

That's an interesting question, I don't know for sure but it makes sense as the West Pacific is the most active basin in the world and most years contain several devestating landfalls with unfortunately, often large death tolls. However, it does appear that storms have to cause a lot more devestation to be retired in this basin, several storms last year killed up to 50 people each yet remained on the naming lists- wheras they probably would've been retired in other basins. Three storms were retired this year, but none were in 2008 or 2007, despite Typhoon Fengshen killing in excess of 1,400 people.