East Pacific Invest Thread

[Cookie]

not much yet with this system!

Edited May 27, 2008 by cookie

[Somerset Squall]

The NHC have it as a moderate chance of developing but it has a lot of organising to do first. The convection is more concentrated than this morning but the low pressure remains very broad. If anything does happen with this invest then it will be very slow to occur.

[kold weather]

Its looking much better this morning. Convection has cotinued to concentrate towards the LLC, which remains fairly tight and strong, hints of curveature starting to show as well which isa nother good sign. Sat.Estimates put this at TD strength presently and given the deep convection and the LLC it has I fully suspect we will see a TD out of this in the next 12hrs.

What happens from then is a little uncertain. statistical models has this system heading off to the NW however the more dependable dynamic models such as the GFDL has it slowly heading NNE towards central America. Given 90E is drifting ENE I'm more inclined to believe in the GFDL idea.

The other issue is how strong this system will become. Right now as I said it does look a lot like a tropical depression. SST's are very warm in the region and upper level conditions do look like they support development though I don't think its quite as favorable as the models think it currently is, esp the SHIPS which show a 35% chance of rapid strengthening occuring in the next 24hrs (they classify that as 25kts gained in less then 24hrs) however it does assume the system is heading away from land. The track probably means it has 48-60hrs over water and in that time there is no reason I foresee that this should be tropical storm Alma, could well be getting into the mid range of TS strength IMO by that time given its current shape and structure. Heavy rains already caused by the instablity across the region will only be increased by any tropical cyclone development.

Finally should be noted given the models do take it northwards towards CA it may well be the case that this system could find its way into the Caribbean and if it does then it may need to be watched there as well but thats probably the best part of a week away yet.

[Somerset Squall]

Thanks for that KW. Certainly does look better than when I posted yesterday, was a real mess and the centre was very broad. But as you say it's tightning up now as there is more curvature. We may have the first storm of the East Pacific season just around the corner!

[kold weather]

Yet another possible system developing from the Monsoon trough present in the region, Invest 91E has been declared currently a little bit south of central America, though a good bit further west then Alma. Looks like its got a good circulation and despite probably only being 24-36hrs away from landfall like Alma I see no reason why it can't develop into something. Track looks increasingly likely to make it into the BoC as upper high breaks down over the Gulf of Mexico where it may need to be watched for any further development in about 72-96hrs time so heads up for that.

[Somerset Squall]

Certainly looking better organised tha this morning and the NHC are flagging up a medium risk for development according to their new scale. Conditions appear favourable, the only thing I would say it has to avoid doing is moving too far north as land interaction may hinder development. Certainly interesting times around Central America at the moment with regards to this monsoon trough (not all that common in this part of the world I'm led to believe!). Time will tell whether we have Boris in the next few days.

Edited June 2, 2008 by Somerset Squall

[Somerset Squall]

It appears land interaction is indeed the main factor hindering development of this system; NHC have downagraded it's potential to low now. Conditions are otherwise favouarable but as this invest is continuing to push northwards inland then development is very unlikely.

[Somerset Squall]

We have invest 92 currently, and the NHC puts it into the medium risk category for development over the next 24-48 hours.

TROPICAL WEATHER OUTLOOK

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

1100 AM PDT MON JUN 9 2008

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

http://' target="_blank">1. A LARGE AREA OF DISTURBED WEATHER ASSOCIATED WITH A BROAD AREA OF

LOW PRESSURE IS CENTERED CLOSE TO THE COAST OF MEXICO ABOUT 100

MILES WEST-SOUTHWEST OF ACAPULCO...AND HAS BEEN MOVING GENERALLY

WESTWARD AT 10 TO 15 MPH. WHILE ATMOSPHERIC CONDITIONS ARE ONLY

MARGINALLY FAVORABLE FOR DEVELOPMENT...THIS SYSTEM APPEARS TO BE

SLOWLY GAINING ORGANIZATION...AND IT COULD BECOME A TROPICAL

DEPRESSION WITHIN THE NEXT DAY OR TWO. REGARDLESS OF

DEVELOPMENT... LOCALLY HEAVY RAINFALL IS POSSIBLE ALONG THE COAST

OF MEXICO FROM PUERTO ANGEL WESTWARD TO NEAR MANZANILLO DURING THE

NEXT DAY OR TWO. THESE RAINS COULD PRODUCE LIFE-THREATENING FLASH

FLOODS AND MUD SLIDES.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE

NEXT 48 HOURS.

$$

FORECASTER KNABB/BLAKE

Image of 92E:

[kold weather]

Yep indeed. There are what appears to be a couple of weak circulations present and pressure has dropped earlier down to 1005mbs in response to this region. Needs to be watched because whilst convection isn't all that impressive at the moment in terms of cloud depth it has got a reasonable circulation and thus as long as it can stay over water it will have a shot at becoming a tropical depression in the next 36hrs as SSt's are warm (estimated at 29C) and shear whilst present probably isn't going to be high enough to prevent development from occuring, just enough to slow its development down to some extent. The big unknown is going to have to be whether it stays offshore or whether it ends up overland.

[Somerset Squall]

We have invest 93E in the East Pacific that has been slowly getting better organised today. Here's what the nhc have to say on the system:

THUNDERSTORM ACTIVITY WITH THE SMALL AREA OF LOW PRESSURE LOCATED

ABOUT 850 MILES SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA

HAS BECOME A LITTLE BETTER ORGANIZED TODAY. ALTHOUGH THE SYSTEM

HAS SOME POTENTIAL TO BECOME A TROPICAL DEPRESSION DURING THE NEXT

DAY OR SO...IT IS MOVING WEST-NORTHWESTWARD INTO AN AREA LESS

FAVORABLE FOR TROPICAL CYCLONE DEVELOPMENT.

Cooler waters lie not far to the northwest, so unless 93E gets it's act together we won't see a tropical cyclone from this. It does however, look a lot better than it did yesterday.

[Somerset Squall]

Well, 93E didn't do anything but we now have invest 94E. To be honest, it's a bit of a mess right now, a very disorganised mass of convection. However, it's in a favourable environment drifing northwestwards, so something may develop but if it does it's going to be slow.

[kold weather]

Deep convection has increased with this invest over the past 12hrs and there does appear to be at least some slight cyclonic turning present with the convection. Still a long way from being closed off mind you but if it is there then its a step in the right direction.

Models are still developing this system in the next 48-72hrs into a tropical cyclone and with such agreement I suspect we will see our next EPAC system from this invest. How strong it gets however is uncertain, the longer it takes to get going the less chance of becoming a noteable system obviously because the further WNW it will head into the cooler waters.

Still we will see, I expect a TD in the next 24-36hrs.

Edited June 25, 2008 by kold weather

[Somerset Squall]

Invest 94E has continued to become better organised and NHC has upgraded it's chances of development to high and JTWC have issued a tropical cyclone formation alert on the system. Convection has increased over a well defined centre.

We also now have invest 95E, west of 94E. The LLC is in good shape but convection is currently limited, so further development will be slow to occur, if indeed there is any further development.

[Somerset Squall]

We now have 96E to the east of Boris. Disorganised convection has gradually become slightly more organised and there are definite signs of rotation with the new invest. The NHC have the system at medium risk level for tropical cyclone development in the next 24-48hrs. Interestingly, if this invest does develop, there is a possibility of interaction with TS Boris.

[Somerset Squall]

JTWC's take on invest 96E:

SUBJ/TROPICAL CYCLONE FORMATION ALERT//

RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN

235 NM EITHER SIDE OF A LINE FROM 11.5N 96.7W TO 14.8N 105.5W

WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY

ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.

WINDS IN THE AREA ARE ESTIMATED TO BE 15 TO 20 KNOTS. METSAT IM-

AGERY AT 291800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED

NEAR 11.5N 97.0W. THE SYSTEM IS MOVING WESTWARD AT 11 KNOTS.

2. REMARKS:

RECENT ANIMATED VISIBLE SATELLITE IMAGERY REVEALS A BROAD AREA OF

CYCLONIC TURNING WITHIN THE MONSOON TROUGH, WITH DEEP CONVECTION

RIDING THE PERIPHERY OF THE TURNING. A DEFINED LOW LEVEL CIRCULATION

CENTER (LLCC) IS EVIDENT IN A 291155Z PARTIAL QUIKSCAT IMAGE WITH

15 TO 20 KNOT UNFLAGGED WINDS NEAR THE CENTER; HOWEVER, VISIBLE

SATELLITE IMAGERY AND A 291426Z SSMIS MICROWAVE IMAGE REVEAL A MORE

ELONGATED LLCC WITH WEAK FORMATIVE BANDING. THE SAME QUIKSCAT IMAGE

ALSO INDICATES STRONG SOUTHWESTERLIES ON THE EQUATORWARD SIDE OF THE

SYSTEM THAT SHOULD AID IN ENHANCING LOW LEVEL CYCLONIC VORTICITY. THE

SYSTEM LIES IN FAVORABLE SEA SURFACE TEMPERATURES AND OCEAN HEAT

CONTENT UNDER LOW TO MODERATE VERTICAL WIND SHEAR WITH COMBINED RADIAL

OUTFLOW. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20

KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB. DUE

TO PHYSICAL SIGNS OF CONSOLIDATION EVIDENT IN THE CLOUD STRUCTURE AND

AN OVERALL FAVORABLE ENVIRONMENT FOR CONTINUED DEVELOPMENT, THE

POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN

THE NEXT 24 HOURS IS GOOD.

3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY

302000Z.//

image:

[Cookie]

96 appears to be nearer warmer waters according to this link?

http://www.wunderground.com/tropical/?index_region=ep

[Somerset Squall]

Indeed it is, that coupled with low shear and favourable outflow should facilitate the development of a new tropical depression tomorrow, judging by the way it's getting itself better organised.

[Cookie]

thanks mate

[Somerset Squall]

Well it appears 96E is really taking it's time despite the good conditions. It's slowly gettig there, but the convection needs to be more concentrated and the LLC a bt better defined before it can be upgraded.

[Somerset Squall]

Aswell as Hurricane Boris and Tropical Storm Douglas, invest 97E has formed, and chances of development look good as conditions are favourable. Certainly a very active start to the East Pacific season! Here's what NHC have to say on the system:

AN AREA OF DISTURBED WEATHER HAS FORMED ABOUT 400 MILES SOUTH OF THE

GULF OF TEHUANTEPEC. ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR

DEVELOPMENT AND THIS SYSTEM COULD BECOME A TROPICAL DEPRESSION

DURING THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY WEST-

NORTHWESTWARD.

Might be jumping the gun but maybe Elida is just round the corner?

Edited July 2, 2008 by Somerset Squall

[Cookie]

its a very good start

[kold weather]

97E is looking very good indeed right now with some deep convection and also an obvious circulation present. Indeed there is even hints of banding with some of the outer bands of the convection which is noteable on the loops. Given everything this should be a tropical depression probably within the next 18hrs and could well become a hurricane down the line with high heat content along the path for at least the next 72hrs at least. Shear currently effecting Douglas may eventually cause weakening in the long term but thats a big uncertainty right now it has to be said. If I was a betting man I'd say SS that Elida is probably only a couple of days away at most.

Edited July 2, 2008 by kold weather

[Somerset Squall]

Thanks for your thoughts on the system KW, certainly looking good at the moment. I wonder if Elida will live up to the Elida of 2002, a monster cat 5. Probably not, but we can dream

http://en.wikipedia.org/wiki/Hurricane_Elida_%282002%29

[Somerset Squall]

Well 97E had a bit of a lull over the last few days and lost a lot of it's organisation, it looked close to TD status a few days ago but ever since it became less organised again. However, 97E has got it's act together once more and looks very healthy on satellite imagery- we may have TD5 on our hands now, encouraging words from the NHC:

SATELLITE IMAGES INDICATE THAT THE AREA OF DISTURBED WEATHER

CENTERED ABOUT 150 MILES SOUTH OF ACAPULCO MEXICO HAS BECOME BETTER

ORGANIZED AND A TROPICAL DEPRESSION COULD BE FORMING. IF THIS

TREND CONTINUES ADVISORIES WILL BE INITIATED LATER TODAY OR SUNDAY.

REGARDLESS OF TROPICAL CYCLONE FORMATION...THIS SYSTEM IS FORECAST

TO DRIFT TOWARD THE NORTHWEST BRINGING GUSTY WINDS AND VERY HEAVY

RAINS TO PORTIONS OF THE COAST OF MEXICO FROM PUERTO ANGEL TO

ZIHUATANEJO DURING THE NEXT FEW DAYS.

Image:

Edited July 5, 2008 by Somerset Squall

[Cookie]

thanks for the updates mate