New African disturbance 96L likely to develop

By: Dr. Jeff Masters , 2:55 PM GMT on September 07, 2009

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A tropical wave (96L) that emerged off the coast of Africa yesterday has organized rather quickly, and will likely become a tropical depression by Tuesday night. Satellite imagery from the European satellite shows a well-organized circulation, but not enough heavy thunderstorm activity near the center of circulation to be considered a tropical depression. The storm is far enough south that the dry air of the Saharan Air Layer is not a major impediment to development. Wind shear is moderate, 10 - 15 knots, and ocean temperatures are 1 - 2°C above the threshold needed for tropical cyclone formation.


Figure 1. Morning satellite image of 96L, off the coast of Africa. The remains of disturbance 95L, which are under 30 - 40 knots of wind shear, can be seen at upper left.

The forecast for 96L
Most of the models develop 96L, and the chances are that this disturbance will become Tropical Storm Fred later this week. The system will initially move west-northwest, but by Thursday, a strong trough of low pressure passing to 96L's north will pull the storm to the northwest, and may be capable of fully recurving the storm to the northeast. However, most of the models foresee that 96L will not move far enough north for this to happen, and that the storm will have to wait for the next trough of low pressure. With the steering pattern for this year continuing to feature plenty of deep troughs of low pressure moving off the U.S. East Coast, the odds of 96L making it all the way across the Atlantic to threaten land areas appear low. Still, much that is unexpected can and does happen in the world of tropical meteorology, and 96L bears watching.

North Carolina low
An area of concentrated thunderstorms has developed off the North Carolina coast in association with the remains of an old cold front. This system is under about 20 - 30 knots of shear, and is not tropical. However, it will bring heavy rain to eastern North Carolina today and Tuesday, as the storm slides north-northeastward along the coast.

I'll have an update Tuesday.

Jeff Masters

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Quoting Seastep:


Any parent knows there is no better gift from God.

Priceless.


man, there is no greater truth in life!!! :)
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Quoting truecajun:


kingzfan104. he was cursing,then told me to shut up because i asked him to please refrain from using God's name in vain.

it all started with him telling iceman not to post short posts. he was looking for a fight.


stupid troll
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Satellite imagery continue to show that TD 7 is organizing, probably TS Fred in the morning.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
Fred at 11?
Photobucket
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alright...I'm out...I'll be back in a couple of days after my ban! LOL
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1230. Seastep
Quoting pearlandaggie:


yep, my kiddos always wanted to go stomp in the puddles! LOL


Any parent knows there is no better gift from God.

Priceless.
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Quoting tornadodude:


who?


kingzfan104. he was cursing,then told me to shut up because i asked him to please refrain from using God's name in vain.

it all started with him telling iceman not to post short posts. he was looking for a fight.
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Quoting truecajun:


thanks. she's a trip!!! she loves her "shoots" -- that's what she calls them rather than boots.


yep, my kiddos always wanted to go stomp in the puddles! LOL
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Quoting futuremet:


NOPE


ok
Member Since: July 24, 2005 Posts: 407 Comments: 19076
1224. hydrus
Quoting cchsweatherman:


Well, the tropical low depicted by the NAM in the Western Gulf is supported by several other computer models so this could be an area to watch closely in the coming days. It seems that wind shear will relax across the Gulf during the next 48 to 72 hours which could allow for something to develop and given that the thunderstorm action has been favoring the Western Gulf, thats where development would be more likely to occur. But, for now, I want to wait and see this actually evolve before becoming sold.

Now, the tropical low depicted by the NAM near Southern Florida is not being supported by any other model I have seen thus far. It will be interesting to see whether any other models start showing this in coming runs. But I have found the NAM does a great job with Florida's complex weather, so much so I use it as my primary guidance over the GFS in developing my forecasts. For now, I can't comment too much on this possible scenario other than saying lets wait and see other model runs and to see whether a catalyst for such development comes about.
I bring this situation up because it is not often that we have two named storms in the Gulf at the same time.
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Quoting pearlandaggie:


LOL...i thought it was me, for a second!

btw...beautiful daughter...in the galoshes!


thanks. she's a trip!!! she loves her "shoots" -- that's what she calls them rather than boots.
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Quoting futuremet:


The NAM 00Z is currently running...we'll see


how long will it be until technology obsolesces the term "currently running"? i suppose the models will become more detailed and offset advances in computing technology...truly amazing times we live in!
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Quoting truecajun:
well maybe it is something to worry about. is this what the NAM is picking up on?


Yes it is... Also StormW and 456 has made comments about the same area yesterday and today....
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Quoting Weather456:
futuremet,

do you actually use the utilizes the NAm when it comes tropical forecasting?


No, I just you use it to see if there any outside possibilities. The NOGAPS and ECMWF is also hinting this, but expect it to be negligible.
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Quoting Dakster:
Futuremet - does the NAM bring the storm across the Florida Peninsula?


The NAM 00Z is currently running...we'll see
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1218. 7544
link to the nam please tia
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futuremet,

do you actually use the utilizes the NAm when it comes tropical forecasting?
Member Since: July 24, 2005 Posts: 407 Comments: 19076
well maybe it is something to worry about. is this what the NAM is picking up on?
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Quoting truecajun:
he's reported.


who?
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Quoting truecajun:
he's reported.


LOL...i thought it was me, for a second!

btw...beautiful daughter...in the galoshes!
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Quoting bwat:
do you think those rainfall totals will move north past the albemarle sound?


I think you quoted the wrong post but

Models expect 1-2 inches as you may now, models underestimate precip

so the Quantitative Precipitation Forecasts (QPF) should be utilized also (up to 4 inches)




24 hr - QPF

Member Since: July 24, 2005 Posts: 407 Comments: 19076
so i've been watching the GOM all day. looks like the convection is waning. nothing to worry about???
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he's reported.
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1207. Dakster
Futuremet - does the NAM bring the storm across the Florida Peninsula?
Member Since: March 10, 2006 Posts: 0 Comments: 10547
1205. the F-4 is my favorite fighter of all time....just edging out the A-10 Thunderbolt II!

rock on!

someone should develop the Phantom II!
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Quoting hydrus:
I was just checking the NAM model, and on the 10th and on the 11th it has two tropical lows in the Gulf, one off the S.W. coast of Florida, and one in the West central Gulf. If you have the time, look at it and give your thoughts on it.


Well, the tropical low depicted by the NAM in the Western Gulf is supported by several other computer models so this could be an area to watch closely in the coming days. It seems that wind shear will relax across the Gulf during the next 48 to 72 hours which could allow for something to develop and given that the thunderstorm action has been favoring the Western Gulf, thats where development would be more likely to occur. But, for now, I want to wait and see this actually evolve before becoming sold.

Now, the tropical low depicted by the NAM near Southern Florida is not being supported by any other model I have seen thus far. It will be interesting to see whether any other models start showing this in coming runs. But I have found the NAM does a great job with Florida's complex weather, so much so I use it as my primary guidance over the GFS in developing my forecasts. For now, I can't comment too much on this possible scenario other than saying lets wait and see other model runs and to see whether a catalyst for such development comes about.
Member Since: April 14, 2007 Posts: 8 Comments: 5169
Post 1189....we get that much rain in an afternoon thunderstorm.
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18Z NAM


12Z NAM



An extended surface trough is expected to form in the eastern Gulf by 48hrs. The models have been inconsistent on where the predominant low pressure centre will form, which is the NAM forecast have been here-and-there with this system. The ECMWF is now expecting it to merge with the Texan low.
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on that pesky Arctic sea ice for a second....since it's SO low, let's look at the data. but first, here are the predictions for this year...

wow...most of these folks predict sea ice levels for 2009 below those for 2008 (the second lowest sea ice extent in the 30 years of data). and yet, 2009 is running above 2008 and may even end up above 2005 after everything is said and done...

if 2009 comes in fourth instead of third, what are the chances that will be reported (nearly zero, I suspect). but wait, 2009 is trending nearly 1 MM sq. km above the low in 2007 and within 500 M sq. km of the high during the JAXA record that occurred in 2003. i'd bet that won't be reported either...neither will the possibility that a lot of the reduced "sea ice extent/area" is the result of packing on one side of the Arctic, resulting in thicker multi-year ice. amazing how that is left out of the discussion (not to mention the attempt to draw conclusions from such a small data set)...shame on you, JM.

oh, and one more thing...how long will this have to go on before such variation is deemed "natural" due to wind and tidal forces...oh wait, that's heresy, right? LOL

sorry for driving the conversation into the ditch, but such B.S. needs to be addressed. i'll see you guys in a couple of days after my ban lapses! ;)

p.s. of course this friggin' post ends up number 1200, which means few will actually see it. sux to be me! :)
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Quoting kingzfan104:
stop posting god damnt. do you have fricken alzheimers or something. jesus you are the biggest post padder i've ever seen


let's not use God's name in vain, please. thanks.
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1195. Seastep
Quoting Relix:
It should be Fred by 5AM. And yes, it will get pulled to the WNW-NW soon. The WSW movement won't be able to save it =P


Valid, but still not buying the first ticket.
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1194. bwat
Quoting kingzfan104:
once again, why do you feel the need to post 9 times with 4 words per post?
do you think those rainfall totals will move north past the albemarle sound?...so sorry, meant to guote 456.
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1191. BDADUDE
Iceman you may get banned soon. Be careful if you like it here. This is a weather site not facebook or myspace. Please be sensible.
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Quoting iceman55:
kingzfan104 u need help


dont engage, you could get ban
Member Since: July 24, 2005 Posts: 407 Comments: 19076
1187. Relix
It should be Fred by 5AM. And yes, it will get pulled to the WNW-NW soon. The WSW movement won't be able to save it =P
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Usually the FNMOC site would post it first. Still a depression as of now.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.