A Gulf of Mexico and an Eastern Atlantic Disturbance Worth Watching

By: Dr. Jeff Masters , 1:53 PM GMT on July 06, 2013

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A tropical disturbance (designated 94L by NHC on Friday) is over the Western Gulf of Mexico, and is headed north towards the Texas/Louisiana coast at 5 - 10 mph. Satellite loops show a modest area of disorganized heavy thunderstorm activity that has been steadily growing this morning. Wind shear has fallen to the moderate range, 10 - 20 knots, since Friday, and the lower wind shear is likely responsible for the increase in thunderstorm activity. A trough of low pressure over the Western Gulf of Mexico is pumping dry air into the west side of 94L, interfering with development. The disturbance should move inland by Sunday morning, bringing heavy rains of 1 - 3" along the Upper Texas and Western Louisiana coasts through Monday morning. None of the reliable forecast models predict that the disturbance will develop, and the disturbance has only a day over water with marginal conditions for development. In their 8 am EDT July 6 Tropical Weather Outlook, NHC gave the disturbance a 20% chance of developing into a tropical depression or tropical storm by Monday.


Figure 1. The Saturday morning NHC Tropical Weather Outlook shows two "Invests" worth watching: 94L over the Gulf of Mexico (area 1), and 95L over the Eastern Atlantic (area 2.) Both were given 20% chances of developing by Monday. Image credit: NHC.

Cape Verdes tropical wave 95L
As we approach mid-July, it's time to begin turning our attention to tropical waves coming off the coast of Africa. We have our first such system worthy of attention today, a tropical wave designated 95L over the Eastern Atlantic near 8°N 33°W, about 800 miles southwest of the Cape Verde Islands. Satellite loops show a modest area of heavy thunderstorms that is showing a moderate amount of spin. Wind shear is moderate, 10 - 20 knots, and ocean temperatures are warm, 28°C. The 8 am EDT Saturday forecast from the SHIPS model predicted that 95L would encounter cooler waters of 27.5°C over the weekend as it headed west to west-northwest at 15 - 20 mph. Wind shear is expected to remain moderate though Monday, which may allow for some additional organization. However, 95L is embedded in a very large area of dry air associated with the Saharan Air Layer (SAL), and July African waves typically have considerable trouble getting organized in the very dry air of the SAL. The disturbance could arrive in the Lesser Antilles Islands as early as Tuesday. A band a strong upper-level winds associated with the subtropical jet stream is expected to be over the northern islands at that time, and if 95L has penetrated as far north as 15°N latitude by that time, it will have to face very high wind shear of 30+ knots. But if 95L stays farther to the south, wind shear should be lower, giving the storm a better chance of development. None of the reliable forecast models predict that 95L will develop. In their 8 am EDT July 6 Tropical Weather Outlook, NHC gave the disturbance a 20% chance of developing into a tropical depression or tropical storm by Monday.


Figure 2. MODIS image of 95L taken at approximately 11 am EDT Saturday, July 6, 2013. Image credit: NASA.

Elsewhere in the tropics
A large upper-level cold-cored low pressure system a few hundred miles north of Puerto Rico will move west over the next dew days, arriving in the Bahamas by Sunday and South Florida by Tuesday. The models do not show that this low will will acquire a surface circulation, and there is only minimal heavy thunderstorm activity associated with it.

In the Eastern Pacific, Tropical Storm Erick is brushing the southwestern coast of Mexico, and is expected to intensify into a Category 1 hurricane on Saturday afternoon. Erick will bring heavy rains of 3 - 5 inches to Southwest Mexico, but the core of the storm is currently expected to remain just offshore. Erick will likely weaken to a tropical storm on Monday, when it will pass just south of Baja.

Cool San Francisco time-lapse fog video
Videographer Simon Christen has created a spectacular 4-minute time-lapse video of fog rushing in past the Golden Gate Bridge into San Francisco. He writes: ""Adrift" is a love letter to the fog of the San Francisco Bay Area. I chased it for over two years to capture the magical interaction between the soft mist, the ridges of the California coast and the iconic Golden Gate Bridge. This is where “Adrift” was born. The weather conditions have to be just right for the fog to glide over the hills and under the bridge. I developed a system for trying to guess when to make the drive out to shoot, which involved checking the weather forecast, satellite images and webcams multiple times a day. For about 2 years, if the weather looked promising, I would set my alarm to 5am, recheck the webcams, and then set off on the 45-minute drive to the Marin Headlands. I spent many mornings hiking in the dark to only find that the fog was too high, too low, or already gone by the time I got there. Luckily, once in a while the conditions would be perfect and I was able to capture something really special. Adrift is a collection of my favorite shots from these excursions into the ridges of the Marin Headlands."


Video 1. Adrift from Simon Christen on Vimeo.

Jeff Masters

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2304. zampaz
Quoting 1988. Skyepony:

It's easy to get lost in my analytical way of thinking.
But in glancing at this image you posted it occurred to me:
As we watch from the distance of space, fluffy clouds of moisture carrying vast amounts of energy roll across our globe and I can't help but think what a beautiful planet we live on. Like the internet in an ideal society, there are no borders. No hard lines. Something we all share and marvel at is the wonder of the physics of our atmosphere and weather.
This is not only an image of a planet but also a snapshot in time of a lot of human beings.
Where were you when this photo was taken. Where was I?
Taking a nap with my cat perhaps.
Thanks for sharing Skyepony.
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2303. vis0
Quoting 1752. AussieStorm:
Earth generates its own solar wind


Thank You AussieStorm for the link.

Glad to see another of my theories from the 1970s being proven. These scientist theorized it in 1992 and now can monitor it by "cluster" . This is part of what i state creates "flying" sphorbs. Sphorbs is my 1970s nickname for what many in the Equatorial (active volcanic regions) think are UFOs. The sphorbs are to the Equator(s) what Aurora Borealis is to the Pole(s). Sporbs can make weird angle turns (90 degrees to even acute).

They're also close to finding a major clue as to what i tap into as to the device i state i use to influence weather. Wish them the best as this energy will revolutionize mankind as electricity did, but i think 10 fold more.

Watch both 94L & 95L if they go INSIDE the ml-d boundaries, see the ml-d's AOI map on my blog,peace
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..
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Quoting 2018. gulfbreeze:
No what would you want next change Hurricanes to 100mph?


No, just TS.
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2300. ncstorm
well this is comforting..

12z CMC
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Quoting 2136. trHUrrIXC5MMX:


tragedies?


Face in palms of hands
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2298. Patrap
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95 升將在某處隨著一些東西去。
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Quoting 2282. tropicalnewbee:


Sebastian that pic gave me chills! Thinking we would get hit by that again (I am in Mims just north of Titusville). I also like the reference of the pic (I assume that was the point) of a low latitude cyclone.
Exactly my woorisome point.
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.
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Quoting 2259. wunderkidcayman:

Yeah name unknown aka Bin Laden


Recon may change to accommodate the location


OT - who was killed this morning?
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Quoting 2290. wunderkidcayman:

What NO!!!!!!!!!! IT'S NOT GONNA GO S AMERICA


What are you basing your opinion on? It could go in almost any direction at this point. Many of the modols don't even have it existing in 120 hours and they certainly don't develop it. As you know the models are terrible at forecasting future movement on a system with no COC to get a fix on.
Are you wishcasting?
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2292. hydrus
If 95L stays weak, it will be more of a threat down the road. The HWRF hangs up the next wave or it curves north right after leaving the coast..All subject to change.
Member Since: September 27, 2007 Posts: 1 Comments: 20546
2291. beell
.
Member Since: September 11, 2007 Posts: 141 Comments: 16265
Quoting 2279. interpreter:


You're right. It's going to make landfall in northern S. America by all indications. Probably Venezuela.

What NO!!!!!!!!!! IT'S NOT GONNA GO S AMERICA
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Quoting 2273. Dakster:


The dismembered ref?
IDK what you mean but I am speaking about a guy on a bicycle that was hit with a motorcycle here this morning. Bicyclist dean and the motorcyclist injured.
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One additional point to consider with 95L, which was a recurring problem last year with some of the peak season TS:

A STRONG TROPICAL WAVE LOCATED ABOUT 1400 MILES EAST-SOUTHEAST OF THE WINDWARD ISLANDS IS MOVING WESTWARD AT ABOUT 25 MPH</em>

25 mph is a very fast speed that is not condusive to vertical stacking..........It will need to slow down considerably in order to organize further towards depression status........Optimum speed is usually 10-12 mph.
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2287. sar2401
Quoting Tazmanian:
do any of the mode runs do any thing with this wave?



Nothing I've seen.
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dos any of the mode runs do any thing with this wave this off the coast?


Member Since: May 21, 2006 Posts: 5091 Comments: 114776
2285. WunderAlertBot (Admin)
JeffMasters has created a new entry.
2284. Levi32
995mb on GFS full-resolution:

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Quoting 2278. rmbjoe1954:
It does seem the islands should take notice and prepare for 95L.


Believe me, we're ALWAYS watching!

-L
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Quoting 2263. sebastianflorida:


Sebastian that pic gave me chills! Thinking we would get hit by that again (I am in Mims just north of Titusville). I also like the reference of the pic (I assume that was the point) of a low latitude cyclone.
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2281. 62901IL
Quoting 2280. MississippiWx:


No, not any reason for that, especially when the new TWO comes out in about an hour. Even with the rapidly spinning low level swirl seen on satellite, I'm not sure that will be enough for the NHC. They are extremely conservative with waves in the Eastern and Central Atlantic, particularly this time of the year when models and climatology don't support development.

Do not expect a TD at the next TWO.
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Quoting 2269. Tropicsweatherpr:
Anyone thinks a Special TWO may come or they wait until 2 PM?


No, not any reason for that, especially when the new TWO comes out in about an hour. Even with the rapidly spinning low level swirl seen on satellite, I'm not sure that will be enough for the NHC. They are extremely conservative with waves in the Eastern and Central Atlantic, particularly this time of the year when models and climatology don't support development.
Member Since: July 15, 2006 Posts: 17 Comments: 10160
Quoting 2252. wunderkidcayman:

I think it will take the Southern plots


You're right. It's going to make landfall in northern S. America by all indications. Probably Venezuela.
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It does seem the islands should take notice and prepare for 95L.
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12z GFS ends the medium range with a moderate-strong tropical storm.

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2276. 62901IL
Quoting 2275. Hurricanes101:
95L may just end up paving the way for the monster wave over Africa.

OK
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95L may just end up paving the way for the monster wave over Africa.
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Quoting 2254. daddyjames:


Nah, the center they'll track is at 10N 44W right about now.

Edit: corrected the horrible typos.


Ooops, let me correct myself:

the center that is being tracked is at 10N 43W right now.

(gotta get the prescription for my glasses checked . . . ) ;)
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2273. Dakster
Quoting 2249. stormwatcherCI:
Ha Ha Ha. don't get too excited. It could just as well be cancelled. Did you know the guy who was killed this morning ?


The dismembered ref?
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Quoting 2255. yonzabam:
Sorry for being off topic but, as I'm a Scotsman, I'd just like to announce that Andy Murray has just won Wimbledon, beating Djocovic in straight sets. Carry on.

Yeah sorry for being off topic as well guys, as i am a scotsman as well (and a Caymanian) congrats to Andy !!!!!!!!!!
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Quoting 2267. beell:


Sometimes...a critical and objective evaluation of the various available sat loops helps.


Yup; many an NHC discussion (usually an upgrade) has begun with "satellite observations indicate that....."
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do any of the mode runs do any thing with this wave?


Member Since: May 21, 2006 Posts: 5091 Comments: 114776
Anyone thinks a Special TWO may come or they wait until 2 PM?
Member Since: April 29, 2009 Posts: 75 Comments: 14071
2268. 62901IL
Quoting 2266. AussieStorm:


Yes!!!!!!!!!!!!!! Arise Sir Andy Murray . Has a good ring to it. Don't it. HAHAHAHAHA. Olympics Gold and Wimbledon Champion.

77 years since a Brit won Wimbledon. I'm in tears, my hands nose and feet are frozen I'm shivering all over, but that was worth it.

Once again....
Goodnight all. I'm off to my warm bed.

Goodnite!
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2267. beell
Quoting 2213. weathermanwannabe:
when it comes to cyclogenesis; this is the toughest area to often predict which is why the models, and model consensus, is the best that we can do at the moment.....


Sometimes...a critical and objective evaluation of the various available sat loops helps.
Member Since: September 11, 2007 Posts: 141 Comments: 16265
Quoting yonzabam:
Sorry for being off topic but, as I'm a Scotsman, I'd just like to announce that Andy Murray has just won Wimbledon, beating Djocovic in straight sets. Carry on.


Yes!!!!!!!!!!!!!! Arise Sir Andy Murray . Has a good ring to it. Don't it. HAHAHAHAHA. Olympics Gold and Wimbledon Champion.

77 years since a Brit won Wimbledon. I'm in tears, my hands nose and feet are frozen I'm shivering all over, but that was worth it.

Once again....
Goodnight all. I'm off to my warm bed.
Member Since: September 30, 2007 Posts: 9 Comments: 15932
2265. 62901IL
Quoting 2262. sebastianflorida:
Link

WTC??
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2264. Melagoo
Quoting 2258. tropicalnewbee:


I am slightly educated with some of this stuff but it seems this solves the closed low argument.


... heeeheeheeeheee heee!
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LETS HOPE NOT!
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Link
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Quoting 2250. sar2401:

That's assuming that 95L gets to 12.5N. It's at 8.40N right now and still has gained very little latitude.


Doesn't matter how far north it is, as long as it's not over South America. Once it reaches 50W or 55W, they are able to investigate. Can't remember which longitude.
Member Since: July 15, 2006 Posts: 17 Comments: 10160
Convection on 95L is starting to wane a little bit but will be interesting to see what happens with d-max tomorrow morning in the early am.....If it is looking real good in the am, it could be bumped up to 60%.

Just my uneducated opinion............ :)
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Quoting 2249. stormwatcherCI:
Ha Ha Ha. don't get too excited. It could just as well be cancelled. Did you know the guy who was killed this morning ?

Yeah name unknown aka Bin Laden

Quoting 2250. sar2401:

That's assuming that 95L gets to 12.5N. It's at 8.40N right now and still has gained very little latitude.

Recon may change to accommodate the location
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Quoting 2235. RTSplayer:
This appears closed.



I am slightly educated with some of this stuff but it seems this solves the closed low argument.
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The GFS hardly does anything with 95L keeps it weak for all its life. That 1014 mb low over the south tip of FL. if I followed the loop correctly is 95L.



Link
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The high in 6-7 days is nowhere near as potent as it is now. As such, the GFS shows this system (not 95L, the wave over central Africa) moving at a typical speed across the MDR.

174 hours:

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Sorry for being off topic but, as I'm a Scotsman, I'd just like to announce that Andy Murray has just won Wimbledon, beating Djocovic in straight sets. Carry on.
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Quoting 2250. sar2401:

That's assuming that 95L gets to 12.5N. It's at 8.40N right now and still has gained very little latitude.


Nah, the center they'll track is at 10N 44W right about now.

Edit: corrected the horrible typos.
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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.