Tropical Cyclone Gene

[Somerset Squall]

No, I wouldn't either!

Gene is rapidly turning extratropical now and I expect the JTWC will issue their final warning at 3pm this afternoon as Gene has become very broad and has taken on the appearance of a strong extratropical cyclone.

[Somerset Squall]

The JTWC explains the current situation regarding Gene a lot better than I can so I'll post the latest warning direct. In short, it seems Gene is holding onto tropical status for longer than anticipated and still has a warm core.

REMARKS:

052100Z POSITION NEAR 28.5S 179.2W.

TROPICAL CYCLONE (TC) 15P (GENE) LOCATED APPROXIMATELY 590 NM NORTH-

NORTHEAST OF AUCKLAND, NEW ZEALAND, HAS TRACKED EASTWARD AT 11 KNOTS

OVER THE PAST 06 HOURS. RECENT ANIMATED INFRARED IMAGERY AND A

051803Z SSMI IMAGE DEPICT A DEFINED, BROADENING LOW-LEVEL CIRCUL-

ATION CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION OVER THE NORTH-

EASTERN QUADRANT. COLD AIR STRATOCUMULUS CONTINUES TO WRAP INTO THE

NORTHERN PERIPHERY OF THE SYSTEM, HOWEVER, THERE IS NO EVIDENCE THAT

THIS DRIER, COOLER AIR IS ENTRAINING INTO THE SYSTEM CORE, AND THE

TPW AND AMSU PRODUCTS CONTINUE TO SHOW A CORE OF WARM, MOIST AIR

SURROUNDING THE CENTER. THE CURRENT INTENSITY IS BASED ON A 050529Z

QUIKSCAT IMAGE WHICH INDICATES 40 TO 45 KNOT WINDS NEAR THE CENTER.

DVORAK INTENSITY ESTIMATES HAVE DECREASED TO 35 KNOTS BUT APPEAR TO

BE TOO LOW DUE TO THE LIMITED DEEP CONVECTION. UPPER AIR ANALYSIS

CONTINUES TO INDICATE THAT THE SYSTEM IS INTERACTING WITH A MID-

LATITUDE TROUGH AND IS UNDERGOING EXTRATROPICAL TRANSITION (ETT).

THIS TRANSITION WILL BE COMPLETE BETWEEN TAU 12 AND 24. ETT HAS

BEEN SLOW WITH THE SYSTEM TRACKING ALONG THE NORTHERN EDGE OF THE

BAROCLINIC ZONE UNDER WEAK MIDLATITUDE WESTERLY FLOW BUT TC 15P IS

EXPECTED TO COMPLETE ETT BETWEEN TAU 12 AND 24. THE DYNAMIC

MODELS ARE IN GOOD AGREEMENT ON TRACK AND INDICATE THAT THE SYSTEM

WILL BECOME EMBEDDED IN THE BAROCLINIC ZONE AFTER TAU 12 AND WILL

BE FULLY CAPTURED BY THE MIDLATIUDE TROUGH. TC 15P WILL CONTINUE

TRACKING EASTWARD OVER VERY COOL SST (NEAR 24C). THIS FORECAST

IS BASED ON THE MODEL CONSENSUS. MAXIMUM SIGNIFICANT WAVE HEIGHT

AT 051800Z IS 18 FEET. NEXT WARNINGS AT 060900Z.//

NNNN

[Cookie]

thanks for the updates mate

[Somerset Squall]

Gene has now completed extratropical transition has it has merged with the baroclinic zone, and has lost all tropical characteristics. Gene was a fairly long lasting storm, lasting a total of 11 days.

[Cookie]

Gene has now completed extratropical transition has it has merged with the baroclinic zone, and has lost all tropical characteristics. Gene was a fairly long lasting storm, lasting a total of 11 days.

a couple of questions for you mate.

whats the

baroclinic zone

?

and secondly why dose it appear that storms are lasting longer at the moment? when It appears all hope has gone they seem to strengthen or is it just coincidence?

[Somerset Squall]

The Baroclinic Zone is an area where there is a sharp contrast between warm and cold airmasses thus creating weather fronts (where two contrasting airmasses meet) and extratropical cyclones. The contrasting air masses are the fuel for extratropical cyclones (extratropical cyclones are the same as depressions that hit us in the UK) and allows them to deepen or weaken. Gene became an extratropical cyclone after merging with the Baroclinic Zone, and is likely to deepen further as an extratropical cyclone as the Baroclinic Zone provides energy for it to do so. Hope that helps, but that's only the very basics and my limited knowledge on the subject doesn't allow me to go into any more detail.

Secondly, your question about longer lasting cyclones. Admittedly, we've had a few longer lasting storms over the past week or so (Fame, Gula and Gene being good examples), but I don't think there is any specific reason for it. Gene was quite slow moving through it's lifetime (due to weak steering currents) and that meant it stayed in the tropics for longer. The reason why it delayed becoming extratropical is because it lingered to the north of the Baroclinic Zone (there we go again :o ) allowing it to hang on to tropical characteristics for a little longer. Gene's track (from UNISYS) shows this:

South of 30S is where the Baroclinic Zone is, and you can see that Gene just about stayed north of the zone for the last couple days of it's life meaning transition to an extratropical cyclone was slow giving the impression it was making a comeback but really it was just a slow death. The main reason though is that Gene was slow moving as I said before, so that's why it lasted 11 days. With Fame, there was only a short track over land so it's core remained intact and as conditions were favourable when it emerged back over water it easily re-developed. Coincidence really that we've had a few systems that have not been willing to give up, I don't think there has been any specific reason for it. Hope I haven't waffled too much, lol.

[Cookie]

no you haven't you've explained it really well. I just kinda noticed that seem to be not giving up the ghost easily. thanks for the responding to both questions,

hopefully we will get more longer last ones, it makes it for more interesting!

[Somerset Squall]

no you haven't you've explained it really well. I just kinda noticed that seem to be not giving up the ghost easily. thanks for the responding to both questions,

hopefully we will get more longer last ones, it makes it for more interesting!

It does indeed, and two more cyclones have formed this morning, the south Indian Ocean is on fire! I will make a thread on them both in a moment.

[J07]

Saw some pictures the other day of a DOC "office" on Raoul, the roof had taken a real battering and not much was left- but structurally it seemed to stand up fairly well. I don't know what the sustained winds speeds/gusts were there though.

[Somerset Squall]

http://www.metoffice.gov.uk/weather/impact...2/18459832.html

Thankfully there weren't any more deaths after the 7 in Fiji.