Wave emerging Africa: (Is Invest 91L)

[Hyperstorm]

Once again GFS drops a hurricane from a CV wave. Is 2013.

I have a very strong suspicion that this is a bad model run. The upper-level trough just west of Portugal that would supposedly "destroy" the wave can already be seen slowing its southward momentum.

I expect to see a resurgeance of the tropical system again in the next couple of runs...

[tolakram]

12Z Euro still has it but not very strong and weakens it at the end of the run.

[Hammy]

Once again GFS drops a hurricane from a CV wave. Is 2013.

I have a very strong suspicion that this is a bad model run. The upper-level trough just west of Portugal that would supposedly "destroy" the wave can already be seen slowing its southward momentum.

I expect to see a resurgeance of the tropical system again in the next couple of runs...

Given the models history with accuracy this year (especially since the upgrade) it would not surprise me in the least to go the entire season without a hurricane east of 60, and I highly doubt there will be an exception here. The unfavorable conditions in the eastern Atlantic seem to be showing no signs of decreasing.

[Hyperstorm]

Once again GFS drops a hurricane from a CV wave. Is 2013.

I have a very strong suspicion that this is a bad model run. The upper-level trough just west of Portugal that would supposedly "destroy" the wave can already be seen slowing its southward momentum.

I expect to see a resurgeance of the tropical system again in the next couple of runs...

Given the models history with accuracy this year (especially since the upgrade) it would not surprise me in the least to go the entire season without a hurricane east of 60, and I highly doubt there will be an exception here. The unfavorable conditions in the eastern Atlantic seem to be showing no signs of decreasing.

Remember that this is only one model run. If we go by accuracy, we'd have to go with all previous runs which showed development. The eastern Atlantic is the most favorable it's been in quite a while. It's no wonder the GFS has been seeing a monster develop out of this disturbance.

[TheStormExpert]

Once again GFS drops a hurricane from a CV wave. Is 2013.

I have a very strong suspicion that this is a bad model run. The upper-level trough just west of Portugal that would supposedly "destroy" the wave can already be seen slowing its southward momentum.

I expect to see a resurgeance of the tropical system again in the next couple of runs...

Conditions overall out in the MDR are as bad as they can get for the peak of the season. Even though this is not an El Niño season it is behaving very well like one. Most likely like a moderate-strong El Niño.

[Gustywind]

Tropical Update
Michael Lowry, Hurricane Specialist, The Weather Channel
Sep 5, 2013 5:00 pm ET
http://www.weather.com/newscenter/tropical/


A tropical disturbance currently over Africa will move into the eastern Atlantic this weekend. Some development is possible as it moves westward next week.

[CrazyC83]

Once again GFS drops a hurricane from a CV wave. Is 2013.

I have a very strong suspicion that this is a bad model run. The upper-level trough just west of Portugal that would supposedly "destroy" the wave can already be seen slowing its southward momentum.

I expect to see a resurgeance of the tropical system again in the next couple of runs...

Conditions overall out in the MDR are as bad as they can get for the peak of the season. Even though this is not an El Niño season it is behaving very well like one. Most likely like a moderate-strong El Niño.

I have never seen so much shear and (to a lesser extent) dry air in the MDR at this time of year. They aren't even letting waves reach areas farther west...

I think the first hurricane of 2013 will have non-tropical origins.

[cycloneye]

A TROPICAL WAVE OVER AFRICA IS EXPECTED TO MOVE OVER THE FAR EASTERN
ATLANTIC OCEAN IN A COUPLE OF DAYS...AND DEVELOPMENT OF THIS
SYSTEM IS POSSIBLE OVER THE WEEKEND AND INTO EARLY NEXT WEEK. THIS
SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE...40
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS.

[Hammy]

I am still not sold on development yet, so many other times the GFS has shown strong hurricanes forming this year and nothing has come of them. I will say though, it would be extremely interesting to watch should the latest GFS track actually play out.

[Gustywind]

Tropical Update
Michael Lowry, Hurricane Specialist, The Weather Channel
Sep 5, 2013 7:41 pm ET
http://www.weather.com/newscenter/tropical/

A cluster of storms currently over Africa will push off the continent into the Atlantic this weekend at which point some development may occur.

[CrazyC83]

Tropical Update
Michael Lowry, Hurricane Specialist, The Weather Channel
Sep 5, 2013 7:41 pm ET
http://www.weather.com/newscenter/tropical/

A cluster of storms currently over Africa will push off the continent into the Atlantic this weekend at which point some development may occur.

Are there any signals that the shear may decrease? It has been there for quite some time, not pushing at all.

[TheStormExpert]

Just a month ago shear was not much of an issue what a difference a month makes, it should be the other way around!

[Gustywind]

Stays at 0%-40%.

2 AM Tropical Weather Outlook

A TROPICAL WAVE OVER AFRICA IS EXPECTED TO MOVE OVER THE FAR EASTERN
ATLANTIC OCEAN IN A COUPLE OF DAYS...AND DEVELOPMENT OF THIS
SYSTEM IS POSSIBLE OVER THE WEEKEND AND INTO EARLY NEXT WEEK. THIS
SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE...40
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS.

[cycloneye]

Up to 50% in five days.

A TROPICAL WAVE OVER WEST AFRICA IS EXPECTED TO MOVE OVER THE FAR
EASTERN ATLANTIC OCEAN IN A DAY OR TWO...AND DEVELOPMENT OF THIS
SYSTEM IS POSSIBLE LATE THIS WEEKEND INTO EARLY NEXT WEEK. THIS
SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS...AND A MEDIUM CHANCE...50
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS.

[tolakram]

12Z GFS still has this, strengthening at 135 hours.



http://www.tropicaltidbits.com/analysis/models/gfs/

I think that Sept 11th record is going to be close.

[Alyono]

I have never seen so much shear and (to a lesser extent) dry air in the MDR at this time of year. They aren't even letting waves reach areas farther west...

I think the first hurricane of 2013 will have non-tropical origins.

you were not around in 1997 then. There was routinely over 80 KT of shear in the Caribbean that year

[Hyperstorm]

Once again GFS drops a hurricane from a CV wave. Is 2013.

Conditions overall out in the MDR are as bad as they can get for the peak of the season. Even though this is not an El Niño season it is behaving very well like one. Most likely like a moderate-strong El Niño.

I have never seen so much shear and (to a lesser extent) dry air in the MDR at this time of year. They aren't even letting waves reach areas farther west...

I think the first hurricane of 2013 will have non-tropical origins.

The conditions in the far eastern Atlantic near Cape Verde are much more favorable now than they were 1-2 weeks ago. The deep trough that was centered W of the Canary Islands for a long time has been displaced to a position that is more favorable for development near the CV islands, even if only temporary. That should allow the disturbance exiting the coast to develop.

Latest GFS at 12Z is back to hurricane development. The difference between this run and the ones from the previous days is that it now develops it strongly just west of the CV islands and not over them. It also shoots it straight north after it crosses them and not NW.

The question now, in my opinion, is not if this one develops...is how strong will it get?

[cycloneye]

A TROPICAL WAVE APPROACHING THE COAST OF WEST AFRICA IS EXPECTED TO
MOVE OVER THE FAR EASTERN ATLANTIC OCEAN IN A DAY OR TWO...AND
DEVELOPMENT OF THIS SYSTEM IS LIKELY EARLY NEXT WEEK. THIS
SYSTEM HAS A LOW CHANCE...NEAR 0 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS...BUT A HIGH CHANCE...60
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 5 DAYS.

[Gustywind]

2 PM Tropical Weather Discussion. Interresting discussion related to this twave...


AN ATLANTIC OCEAN TROPICAL WAVE WAS ANALYZED ALONG 18W/19W TO
THE SOUTH OF 20N. FURTHER ANALYSIS OF THE SITUATION GIVES US THE
IDEA THAT THE WAVE REALLY STILL IS MORE INLAND IN AFRICA...AND
NOT IN THE ATLANTIC OCEAN YET. IT MAY TAKE ANOTHER DAY OR TWO
FOR THE WAVE TO EMERGE FROM AFRICA. CONVECTIVE PRECIPITATION...
NUMEROUS STRONG FROM 13N TO 15N BETWEEN 17W AND 18W...AND FROM
9N TO 10N BETWEEN 18W AND 20W.

[Blinhart]

pic?????