EPAC Potential

[Anonymous]

The UKMET first began to hint on the formation of a weak area of low pressure on Wednesday. Today, the model is now forecasting rapid intensification. The Euro and NGP have also joined the party. NOGAPS isn't forecasting significant development. However, it does show slow development through 144 hours. What are the models picking up?

http://www.met-office.gov.uk/sec2/sec2c ... wtnt80.txt

http://www.ssd.noaa.gov/PS/TROP/DATA/RT/EPAC/IR4/20.jpg

There are two weak disturbances between 100-110W. Each model forecasting development is developing one of the two systems. Shear and subsidence is dominating much of the EPAC at the moment. But the second area of convection is being somewhat protected from the shear. Upper level winds would still have to decrease in order for development to take place and that is what some of the models are showing.

The GFS isn't forecasting development. But the problem may be that the model is trying to develop another area of low pressure too far west. The GFS storm would use up all of the energy that is supposed to be going to the convection to the east. Nothing can develop that far west due to more hostile conditons.

Based on climatology, what is the avg chance of an EPAC May storm? Well, based on climo starting in the early 1970s, there is almost a 50/50 shot at development. But we have been starting a trend since 2000....

Hurricane Aletta
22 - 28 May, 2000

Hurricane Adolph
25 May - 1 June 2001

Hurricane Alma
24 May - 1 June 2002

Tropical Storm Andres
19 - 25 May 2003

If it weren't for the models, the eastern Pacific disturbances would not have caught my attention. So I would say that the probability for development next week would be about a 5 on a scale of 1-10. If we begin to see more model support and consistency over the next few days, then obiously the probability would increase. Conditions aren't good enough yet to be hyping development imo. Btw, I have to give credit to Rob for noticing the UK a couple days ago.

[cycloneye]

It is always very interesting to follow the EPAC systems because we can see how the whole structure develops in open waters without affecting any landmasses with a few exceptions when some of them recurve going to the Mexican coast and a handfull that can make it to the Hawaii longituds.

[wx247]

Thanks for the heads up. Something to watch indeed.

[Anonymous]

SURFACE SYNOPTIC ANALYSIS 14/1800 UTC...
...WEAK TROPICAL WAVE ALONG 108W FROM 5N TO 17N MOVING W 10 KT.
...1025 MB HIGH PRES CENTER AT 33N135W RIDGES SE TO 18N110W.

[Typhoon_Willie]

Interesting stuff indeed. Something that we will follow!

[Anonymous]

This is getting crazy now....


The UKMET is now developing two tropical cyclones


068

WTNT80 EGRR 150540

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC



AND NORTH ATLANTIC



GLOBAL MODEL DATA TIME 00UTC 15.05.2004



NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 24 HOURS

FORECAST POSITION AT T+24 : 10.9N 106.9W



VERIFYING TIME POSITION STRENGTH TENDENCY

-------------- -------- -------- --------

00UTC 16.05.2004 10.9N 106.9W WEAK

12UTC 16.05.2004 10.0N 109.4W WEAK LITTLE CHANGE

00UTC 17.05.2004 10.0N 109.4W WEAK INTENSIFYING SLIGHTLY

12UTC 17.05.2004 10.5N 109.1W WEAK LITTLE CHANGE

00UTC 18.05.2004 11.0N 109.3W WEAK LITTLE CHANGE

12UTC 18.05.2004 11.3N 109.3W WEAK LITTLE CHANGE

00UTC 19.05.2004 12.1N 109.4W WEAK LITTLE CHANGE

12UTC 19.05.2004 12.7N 110.5W MODERATE INTENSIFYING SLIGHTLY

00UTC 20.05.2004 12.9N 111.1W MODERATE INTENSIFYING SLIGHTLY

12UTC 20.05.2004 13.1N 111.8W MODERATE LITTLE CHANGE

00UTC 21.05.2004 13.5N 111.9W MODERATE INTENSIFYING SLIGHTLY



NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 24 HOURS

FORECAST POSITION AT T+36 : 9.3N 92.3W



VERIFYING TIME POSITION STRENGTH TENDENCY

-------------- -------- -------- --------

12UTC 16.05.2004 9.3N 92.3W WEAK

00UTC 17.05.2004 10.0N 94.0W WEAK LITTLE CHANGE

12UTC 17.05.2004 10.3N 95.1W WEAK LITTLE CHANGE

00UTC 18.05.2004 10.2N 95.4W WEAK INTENSIFYING SLIGHTLY

12UTC 18.05.2004 10.3N 95.3W WEAK INTENSIFYING SLIGHTLY

00UTC 19.05.2004 10.0N 95.3W WEAK LITTLE CHANGE

12UTC 19.05.2004 10.0N 95.3W WEAK LITTLE CHANGE

00UTC 20.05.2004 10.0N 96.0W WEAK LITTLE CHANGE

12UTC 20.05.2004 10.3N 97.0W WEAK LITTLE CHANGE

00UTC 21.05.2004 11.0N 97.5W WEAK INTESNIFYING SLIGHTLY





THIS INFORMATION IS PROVIDED AS GUIDANCE FOR TROPICAL CYCLONE

RSMCS. IT REQUIRES INTERPRETATION BY TROPICAL CYCLONE SPECIALISTS

AND SHOULD NOT BE CONSIDERED AS A FINAL PRODUCT


The NOGAPS model is no longer being as aggressive with the first one...but now it's showing the second system posing a threat to Mexico.

https://www.fnmoc.navy.mil/products/WXM ... opepac.gif

The longer the models continue to show development from one of the two systems, the better the chances for development within the next 5-10 days.

[MGC]

Other than a fairly active ITCZ, I see nothing on the horizon. But, keep looking at the models as one will eventually get it right.....MGC

[Anonymous]

The area between 100W-110W and south of 10N is now condusive for cyclogenesis in terms of upper level winds. If the disurbed area of wx to the east can make it that far west it may have more of a chance. The ITCZ across the PAC is being enhanced by the MJO this week.

[Derek Ortt]

I can guarantee that Bracknell will bust, there isnt going to be a storm by 12Z tomorrow, not even a worthy disturbance out there, merely ITCZ action. Plus, shear is quite high in the region