Invest 99L in Central Atlantic

[cycloneye]

I think we should remember that a computer model forecast that is based on many factors, when just one of those factors fails, the forecast fails. Because of this, using computer forecast for long range forecast is a very uncertain science. Computer forecast should be used for 24 to 48 hours, because the large errors start beyond that. GFS has been proven over the past years to be one of the most reliable, and that's why the NHC uses it as much as they do.

Nonetheless, even if technology continues to improve, it will still be a forecast!!!

Well said Sandy.

[Bane]

I think we should remember that a computer model forecast that is based on many factors, when just one of those factors fails, the forecast fails. Because of this, using computer forecast for long range forecast is a very uncertain science. Computer forecast should be used for 24 to 48 hours, because the large errors start beyond that. GFS has been proven over the past years to be one of the most reliable, and that's why the NHC uses it as much as they do.

Nonetheless, even if technology continues to improve, it will still be a forecast!!!

completely agree. you stated what i was trying to point out much more eloquently.

[cheezyWXguy]

Well the GFS forms a 1010 low near the cape verdes in only 18hrs, and keeps it thru at least day 5

18hrs:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _018.shtml

[alan1961]

yes cheezy the blob due south of the cape verdes on this sat image is the one i think the GFS starts developing

http://www.meteo.psu.edu/~gadomski/SAT_ ... ntvis.html

[cheezyWXguy]

Is it me or did the 18z GFS initialize wrong? After 30 hours, it continues to bring a string of highs across, instead of what Id assume were ment to be lows...Ive heard of the wave train, but not the high train

GFS at 30hrs
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _030.shtml

[alan1961]

this seems to run the low train

http://moe.met.fsu.edu/cgi-bin/gfstc2.c ... =Animation

[cheezyWXguy]

I dont think that run is very reliable...in the entire 7 days, the low it forms in 24 hrs only moves 5 degrees W between then and 168hrs

[philnyc]

I dont think that run is very reliable...in the entire 7 days, the low it forms in 24 hrs only moves 5 degrees W between then and 168hrs

Yeah, I noticed that this morning. The GFS shows a 1012mb low moving off of Africa (that African easterly wave moving off now), gettting to about 30W but then stalling and/or dissapating. The other 3 panels don't show any atmospheric reasons for a stallout, so it must be forecasting too much dry air entrained into the system resulting in a dissipation. That's the only scenario that makes sense.

Here's the e-wall loop (limited shelf life):

http://www.meteo.psu.edu/rtwx/ewall/GFS ... sloop.html

P.S. Notice the shear forecasts in the lower left panel. Shear forecasted to go WAY down in the MDR between now and August 1st.

[Weatherfreak14]

Models tonight still hint a low pressure maybe a depresson. but now its showing the wave prolly wont make it to the US unless the conditions become more favorible.

[philnyc]

Models tonight still hint a low pressure maybe a depresson. but now its showing the wave prolly wont make it to the US unless the conditions become more favorible.

Yeah, we're all still getting excited about something developing when the atmosphere isn't really indicating it yet. One or two weeks from now, yes. But not before then. It seems to me that this season is going to have a lot of strong storms, and the Bermuda high setup, should it stay that way, is indicative of some landfalls here. But it's still too early. We all know, if we want to be honest, that Cape Verde storms don't appear until early or mid August. 2005 was a completely freaky year that we may not see again for decades.

[Sanibel]

Disagree with "the atmosphere is not really indicating". If you look at the ITCZ it has a very subtle sign of waves starting to 'stick' as they cross the mid-Atlantic. Looks like prime time almost where suddenly one of those little surviving convection areas spins.

[philnyc]

Disagree with "the atmosphere is not really indicating". If you look at the ITCZ it has a very subtle sign of waves starting to 'stick' as they cross the mid-Atlantic. Looks like prime time almost where suddenly one of those little surviving convection areas spins.

I said not NOW, but then "in one or two weeks, yes". I agree with you about "prime time almost". But at least a week to go...

[cheezyWXguy]

Disagree with "the atmosphere is not really indicating". If you look at the ITCZ it has a very subtle sign of waves starting to 'stick' as they cross the mid-Atlantic. Looks like prime time almost where suddenly one of those little surviving convection areas spins.

I said not NOW, but then "in one or two weeks, yes". I agree with you about "prime time almost". But at least a week to go...

Yeah...it is getting close to that time of year, however shear and SAL are unfavorable at this time, but in 1-2 weeks, that should change

[MGC]

Little chance this far out. I wonder how many tropical cyclones the models spin up during the year. If you beleived the models there would be 100 TC's every season.....MGC

[philnyc]

Little chance this far out. I wonder how many tropical cyclones the models spin up during the year. If you beleived the models there would be 100 TC's every season.....MGC

LOL. Especially the CMC. Gotta love them if you're a hurricane follower.

[Hyperstorm]

Of course, we have to be reminded that tropical cyclones don't have a calendar to go by. If conditions are favorable or "August-like", the storm will not wait to form until the calendar says it's August...

In my opinion, while conditions are not currently optimal for development, we are getting VERY close...It won't be long...

[philnyc]

Disagree with "the atmosphere is not really indicating". If you look at the ITCZ it has a very subtle sign of waves starting to 'stick' as they cross the mid-Atlantic. Looks like prime time almost where suddenly one of those little surviving convection areas spins.

I said not NOW, but then "in one or two weeks, yes". I agree with you about "prime time almost". But at least a week to go...

Yeah...it is getting close to that time of year, however shear and SAL are unfavorable at this time, but in 1-2 weeks, that should change

Absolutely. One thing a lot of people forget is that shear and SAL almost always start out high and then gradually diminish as we move into August. SAL is related to the Mid Level African Easterly Jet in ways nobody really understands well yet. And shear is also obviously very complex, being related to El Nino, Nina, among other things. But the climatology shows us very clearly that both NORMALLY ease as we go into August. It's not a coincidence that the climatology also shows us that Cape Verde season doesn't get going until August. If you think of it that way, and look at the current model forecasts, such as GFS global, everything is on schedule for a dropoff in SAL and shear.
BTW, here's the climatological norm for the MLAEJ during July 1 to July 19 for 1968-1996:


and here's the July 1 to July 19 2007 config:


Since (so far) the MLAEJ is stronger and farther north than usual, it is one of several indicators that still point to an active CV season. But all that goes BOOM can go BUST. We'll see.

[skysummit]

I'm still liking this wave as it's crossing the Central Atlantic.....

[DESTRUCTION5]

I'm still liking this wave as it's crossing the Central Atlantic.....

Looks good...Real good..

[windstorm99]

Yea i was just looking at that wave as thunderstorm activity has been on the increase.