CybrTeddy's tropical weather blog

Don completely croaks, 91L likely to be Emily 7/30/11

By: CybrTeddy, 8:13 PM GMT on July 30, 2011

Good afternoon and welcome to my tropical weather update for Saturday, July 30th, 2011. The tropics remain fairly active today, with our main feature being invest 91L but first I want to give a little summary on the dramatic death of 91L. I was taken by surprise when I got home to see not only did Don arrive earlier than I expected but Don was gone. I couldn't even find any real convection with it. What killed it was extreme dry air intrusion, Don always had a problem with it with its weak and small size, but never in the last 5 years have I seen a storm dissipate so suddenly. I guess by advisories Don made landfall as a 50mph Tropical Storm.. but it was probably already a low-end TD. Texas killed the very thing it needed most, rain. I feel sick to say it, but the drought is real bad there, but the only way Texas will solve the drought is a hurricane. This will obviously be my last discussion on Don.

91L likely to become Tropical Storm, maybe even Hurricane, Emily.
Our main feature today is strengthening tropical invest 91L. 91L's pressure is currently 1008mb and the winds are 30mph. Satellite reveals that 91L is becoming better organized, earlier today it had a linear look to it and since as I thought it would has gained a circular look to it. The NHC has a 80% chance of development for 91L and that's where I am to, this will probably be our 4th storm of the month tomorrow. If 91L gets named tomorrow as Emily, it would mark the most active early season since 2005, which had 7. Right now it appears 91L's circulation isn't quite closed but its certainly getting there. There is a recon planned into 91L tomorrow, several actually, and they should find a Tropical Depression maybe even a Tropical Storm.

(fig 1. Invest 91L as of this update)

Run down of the models.
At this time, all of the reliable models develop this into a tropical cyclone. The CMC, NOGAPS, and GFS develop this into a strong system while the ECMWF is the weakest with barely a TD. The CMC and GFS bring 91L out to sea after hitting Hispaniola. However, I will try not to speculate on a extended forecast other than the next few days which appears the islands will get hit first.

(fig 2. Latest computer model spaghetti tracks)
The GFS is pretty aggressive with this system, bringing it up a hurricane as it stalls out in the Atlantic. It hits pretty hard the islands with a probable Category 1 hurricane judging by the closed isobars though the pressure does not reflect that. It also delivers a punch of rain and winds to Puerto Rico, which is the exact opposite of Texas from what I understand - they've had enough rain.

(fig 3. GFS model run showing the storm stalling out)
The CMC and NOGAPS also bring this up to a strong TS to a hurricane, though they differ in track. The CMC is similar to the GFS, hits Puerto Rico then heads out to sea but the NOGAPS has it hitting Hispaniola as a decent system, then weakening it followed by intensification until it makes landfall in Florida by next week. This is possible if the cyclone remains weak. The ECMWF has been absolutely refusing to develop 91L to a tropical cyclone, but the latest run shows a probable TD hitting Hispaniola before weakening it considerably to its death as it passes over.

(Fig 4. The CMC model)

(fig 5. The ECMWF model)

The reason the models are showing a recurve out into the ocean is because the models are predicting a trough to be in place as it passes by the islands. However this trough is like the one I mentioned that the models where showing would recurve the system that became Don, 90L. This trough is stuck between two highs and should be leaving fairly quickly. It all comes down to timing and intensity. There is also a weak but defined tropical wave to the north of 91L. It will be interesting to see if that causes it to be further south to just north of Hispaniola. If so, the chances of a US landfall increase. It is too early at this time to make a guess where this is going however.

The GFS is showing two more systems developing behind 91L, this is a sign that the wave train is really beginning to pick up.

CybrTed

No change to Don, new African wave worth watching 7/28/11

By: CybrTeddy, 7:19 PM GMT on July 28, 2011

Good afternoon and welcome to my tropical weather update for Thursday, July 28th, 2011. Our main focus is on two areas of interest today. The first being Tropical Storm Don, located at 24.6°N 90.7°W. Maximum sustained winds are now at 45 mph and a higher pressure of 1005 mb. Don is gradually mixing out the dry air in its core as a new blowup of convection has just appeared over the center of circulation which itself has been exposed throughout the day due to northerly wind shear. Watches and warning exist all the way from north of the Rio Grande to San Luis, Texas. Don is moving NW at 15 mph and landfall is expected sometime on Saturday.

(fig 1. Tropical Storm Don as of this blog update)

Forecast for Don.
At this time it appears likely that the intensity for Don will be limited due to the dry air from the United States and the wind shear that is effecting this. Now the wind shear is not all that strong and as it nears the coast it should weaken. However, this is a small system and smaller systems are more prone to weakening under less adverse conditions than a larger system would be. Based on these factors, it appears likely that Don will not be able to obtain hurricane status and may not get any higher than 60mph as it makes landfall in Texas.

Don is under the influence of a ridge located over the United states. As this ridge is predicted to remain in place over the United States the next few days it is unlikely Don will deviate much from its predicted landfall point, if it strengthens however judging by the steering forecast it will be forced more south and if it weakens it will be forced more north than predicted.

(fig 2. Forecast track for Tropical Storm Don as of 2pm)

Atlantic tropical wave worth watching.
Another area of interest is perhaps our most well defined Tropical wave west of the Cape Verde islands. Most if not all the models show a low pressure area spinning up with this and I expect at least an invest out of this before too long. The CMC and NOGAPS are the most aggressive, having this become a near hurricane as it nears the islands. It appears that this wave will likely be forced more north than the invest 90L that became Don was, and maybe even north of Hispaniola. This is supported by the CMC and NOGAPS once again. The GFS and ECMWF are the least enthusiastic about this system, though the GFS is the least aggressive and the ECMWF is slightly more aggressive, but does develop this into a tropical cyclone. We need to watch this wave carefully.


We're already on our 4th named storm of the year, talking about the possibility of our 5th before the weekend is out. Pretty telling of what kind of season this might be.

CybrTed

90L on the verge of becoming TD#4, two waves to watch 7/27/11

By: CybrTeddy, 3:16 PM GMT on July 27, 2011

Good morning and welcome to my tropical weather update for Wednesday, July 27th, 2011. 90L has become much better organized over the last 12 hours and appears poised to become Tropical Storm Don, maybe even Hurricane Don. 90L's a small system however, and it is easily effected by the variables of wind shear and warm SST's, meaning it could rapidly intensify or not intensify at all. Such predictions though are far out at this time though. Satellite reveals a well organized albeit small system, spiral bandings are appearing on all but the northern quadrant which appears to be in the process of being effected by some northern shear, as the edge of the circulation is visible. The swift change in organization has prompted the NHC to raise the system to 80% red on the TWO, and it appears likely that later today we could have Tropical Storm Don. Surface indications are starting to show westerly winds and pressures dropping to around 1008 mb, probably lower at this time. This is indicative of a surface low pressure center, and that surface circulation will continue to become better defined as the day progresses.

(fig 1. 90L as of this blog post, nearing TD status)

Track and intensity possibilities.
The computer models have done absolutely poorly on this system. Only the non-tropical NAM showed this developing into an all out tropical storm as it appears to be on the verge of doing. I think this is because the models do very poorly with small systems, as 90L certainly is one. This tells me that any model showing no development is not picking up the initial conditions correctly as they failed to do with Bret and Cindy. The steering currents in place appear that 90L, Don by then more than likely, will continue WNW towards Texas.. perhaps becoming a hurricane in the processes if shear cooperates. The consensus of the models is that this storm will come in north of Brownsville as a high end Tropical Storm or low end Category 1 hurricane. This seems reasonable to me, and it is possible that it could strengthen as it reaches the Texas coast.

(fig 2. 90L's spaghetti model runs as of 12z)

Waves to watch.
Another tropical wave that is worth watching is nearing the islands right now, and it is pretty good on the convection side however there is no closed circulation and hardly much in the way of cyclonic turning. The NOGAPS develops this system into a tropical cyclone as it heads into the GOMEX. Another wave to watch also is shown as a strengthening wave nearing the islands. This is supported by the GFS, CMC, and ECMWF that all show a more than likely invest nearing the islands this week into early August. I will keep a close eye on this as the situation unfolds.

(fig 3. Waves to watch as of this blog post)

CybrTed

Invest 90L a possible threat to develop 7/26/11

By: CybrTeddy, 2:13 PM GMT on July 26, 2011

Good morning everyone and welcome to my tropical weather update for Tuesday, July 26th, 2011. Over the last few days, that tropical wave we have been watching moved into the Greater Antilles and got tagged 90L, and has been very unimpressive until now. I have been very hesitant to do an update on 90L, mostly due to the lack of model support, organization, likelihood of death over land, ect but now it has been sitting just S of Cuba and gaining organization over the night. The NHC has upped their odds to 20% in the next 48 hours, I would put the odds at 30%. Surface pressures around 90L are beginning to fall, indicating that a surface low might be starting to develop. Pressures are around ~1010mb according to the data obs.

(fig 1. Current image of 90L, the 'L' indicates where the center is pinned to be on the ATCF)

Run down of the models and my personal predictions.
Through most of its lifetime the models have been very hesitant to develop any sort of low pressure with 90L and most of them continue to refuse to allow 90L not to develop. This is most likely do to the trough that is draped over the Gulf of Mexico creating moderate shear, but we've seen systems develop in far worse. The most aggressive, if you can call it that, is the NOGAPS followed by the GFS. They both show increased vort nearing TD status at landfall just south of Brownsville. The ECMWF strings 90L into a weak trough over the GOMEX, same with the CMC. I think the models 'might' be overdoing the conditions in the Gulf, or under doing the initial conditions as they did with Bret.

(fig 2. Latest model consensus on a track for 90L)

I personally believe that 90L might make a shot at TD#4 in the GOMEX, and that if it does this situation will be very similar to Tropical Storm Erin in 2007. Erin developed from a wave just like 90L in the GOMEX and hit Texas, bringing a lot rain to them, something they seriously could use right now. However, it does not appear that any of the models are showing 90L going through the bulk of Texas, rather bringing it into northern Mexico just south of Brownsville due to the persistent upper ridging to the north of 90L. There is also as I mentioned a strung out trough in the GOMEX, bringing moderate shear over the system. Based on that, I believe that this system won't become very strong, 50 mph at best before a landfall. It is equally as likely that 90L will completely die in the GOMEX, with no development. I think 90L has a 40% of development in the GOMEX, with a 10% in the Caribbean.

(fig 3. Latest model intensity)

CybrTed

Bret weakening, TD#3, African wave a threat to develop next week 7/20/11

By: CybrTeddy, 7:29 PM GMT on July 20, 2011

Good afternoon and welcome to my tropical weather update for Wednesday, July 20th, 2011. The tropics are active to say the least this day with two active cyclones in the Atlantic. This is the first time this has occurred in the month of July since the infamous 2008 season.

Tropical Storm Bret continues to weaken.
The first area of interest is struggling Tropical Storm Bret, which is now down to 45 mph. Bret is being lifted northward by a ridge that is causing also shear to be plunged into the circulation. Bret has been plagued by dry air since it was declared a Tropical Cyclone a few days ago, this is why trough split develop cyclones are rarely intense and often dissipate. The trough they split from plunges dry air into their circulations causing them to dissipate. Satellite shows that Bret is in the process of dissipation, cloud tops continue to warm and continue to be pushed south away from the center of circulation. As the center of circulation is exposed from the convection it should begin to gradually broaden out and weaken over the next day or so and could dissipate as soon as tomorrow morning.

(fig 1. Tropical Storm Bret as of this blog post.)

Tropical Depression #3 forms, likely to become Tropical Storm Cindy.
The competing circulation that was there when Bret was developing also separated from the same trough and developed into a Tropical Cyclone. TD#3 developed in a similar manner to that of Tropical Storm Chantal in 2007, and will likely be short lived as it is moving 20 mph into cooler waters. It has about 36 hours left over warm waters until it can develop into a stronger system. Based on that, I do not think TD#3, certainly Cindy by then, will become that strong of a system, maybe 50-60 mph at best before weakening in the cold waters and increased windshear. TD#3's formation proves once again you just have to take your eyes off the models and look at the actually conditions then judge if it will develop like I said on my last blog. A week ago, none of the models showed two tropical cyclones developing and active on this date, and it proves just how inaccurate they can be. TD3/Cindy is only a threat to shipping.

(fig 2. Tropical Depression #3)

African wave that could be a threat to be Don down the road.
The final area of interest is a tropical wave, a massive one, currently by 40W 10N. Most of the convection is within the ITCZ and is not a threat at all to develop within the next 48 hours. However the models are hinting at development down the road. This situation is very tricky, ITCZ separating systems often require the TUTT to get it to start going. The setup reminds me of Tropical Storm Bonnie from 2010, though this if it does develop should not be plagued by persistent ULL's. The models are really on and off about this system, some have it become a tropical storm, some kill it. The UKMET and CMC both have this developing, the 00z ECMWF had this developing on the 00z run but has since backed off again. The ECMWF is showing similar poor consistency as it did with Tropical Storm Colin last year, the 00z has a system, the 12z doesn't, and the cycle begins to repeat itself.

(fig 3. African wave worth watching.)

The tropical wave will be heading WNW over the next few days at about 10-12 mph across the tropical Atlantic. As this wave moves WNW it will probably pass north of Puerto Rico and off the United States there will be a trough waiting for it. However because of a building ridge the trough will be kicked out of the way pretty quick right as the system is north of Hispaniola. What the CMC shows happening is the ridge not building in the weakness and it begins to recurve out to sea. The 00z ECMWF showed it being effected by the weakness, then being pushed into Florida by the building ridge. This would make sense, but the timing would have to be absolutely perfect for this to happen. It could be like the 12z ECMWF is showing, the ridge pushing this clear into the islands and not developing it. Regardless, we'll watch the situation that is unfolding very carefully.

CybrTed.

Bret weakens, 99L, African Wave to watch 7/19/11

By: CybrTeddy, 11:56 PM GMT on July 19, 2011

Good evening and welcome to my tropical weather update for Tuesday, July 19th, 2011. The tropics are active today, with Tropical Storm Bret, newly declared invest 99L near Bermuda, and a very well defined Tropical Wave in the CATL. I want to focus on all of these areas, but it looks like the wave in the CATL needs to most watching over the next few days.

Tropical Storm Bret weakens, not expected to strengthen further.
Tropical Storm Bret failed to become Hurricane Bret yesterday, as not to long after my blog post yesterday Bret gulped in a massive amount of dry air and completely shattered the core though it probably maxed out at 70 mph according to the Recon, though the NHC went conservative and set the peak intensity at 65 mph. Bret is also facing very high shear that is causing the center of circulation to become exposed away from the limited deep convection. All this combined, Bret has more than likely peaked and is unlikely to become our first hurricane though it got close.

(fig 1. Tropical Storm Bret.)

Bret is under the influence of the ridge centered over the United States that is forcing it out to sea, and a general NNE motion should continue and accelerate as Bret moves forward in the timeline. I will probably do one or maybe two more updates on Bret, but Bret is not a significant system anymore. It is interesting to note however how badly the models failed with Bret - none of the models picked up on a developing Tropical Storm that attempted to make hurricane status and indeed are still downplaying this system's existence. It just proves how sometimes you need to take your eyes off the models and look at the actual conditions then judge if it will develop or not.

(fig 2. Predicted track for Bret, away from land.)

Invest 99L out in the Central Atlantic might become Tropical Storm Cindy.
Our next area worth watching is just declared invest 99L currently located just east of Bermuda moving due east at nearly 8 knots. 99L formed from a trough split just like Bret did but formed right next to Bret. This was the circulation that I mentioned that was competing with Bret, and was predicted to strengthen even then. I figured that this would attempt to develop on its own but not as a tropical identity. The models, unlike they did for Bret, showed 99L develop as well and as such I made a call a few days ago to watch this area for non-tropical development that could become sub-tropical. It appears at this time 99L will be fully tropical, and if 99L was threatening land it would have probably been declared Cindy already. 99L is not a threat to land over the next few days and is only a shipping interest.

(fig 3. Invest 99L)

African wave worth watching.
A tropical wave currently along 35W appears to be our other area to watch closely to mischief. It is now mid to late July, and its time we start looking out there for cyclones to start to spin up. This particular tropical wave is perhaps the strongest and most defined this year. Most of the convection however is associated with the ITCZ and needs to separate for any further development to occur. As the wave heads westward the models predict convection will increase and it will lift out of the ITCZ as it interacts with the TUTT and convection will flare. This would be a similar setup to lat years Tropical Storm Bonnie - and is worth watching as I doubt conditions will be as hostile as they where for Bonnie. The models all indicate that at least a decent looking disturbance will come from this wave as it heads north of the islands. It could be picked up by a trough and miss the USA though, but that is too far out to determine at this time.

(fig 4. Our next area to watch for cyclone development over next weekend.)

I'll have an update as soon as conditions and changes warrant it.

CybrTed

Tropical Storm Bret intensifying, not a threat to land 7/18/11

By: CybrTeddy, 7:51 PM GMT on July 18, 2011

Good afternoon and welcome to my tropical weather update for Monday, July 18th, 2011. Our main feature is Tropical Storm Bret out near by Florida which developed from a stalled out trough. Bret is located at 28.1°N 77.3°W with maximum sustained winds of 50 mph, though the latest recon indicates a stronger system around 65-70 mph. Bret is moving NNE at 6 mph and this general motion should continue with an increase in speed. Satellite shows Bret has become better organized today, with an eye-like feature on radar and on IR and Visible. This could become a hurricane sometime today. Recon is showing the pressures have decreased to 996 mb, and further strengthening is likely.

(fig 1. Tropical Storm Bret as of 19:45 UTC)

Bret is not a threat to land with the exception of unlikely Bermuda and less likely the outskirts of North Carolina. The latest models indicate that Bret will be pushed NNE out to sea due to a building ridge and a mid-level trough off the coast that is causing a NNE movement. This movement should continue over the next few days with a gradual acceleration. Bret is faced with dry air to its north which is restricting banding features on all but the eastern side. However, it is possible that Bret could become a Category 1 hurricane before weakening.

What else is out looking for in the Atlantic.
The ECMWF has been hinting on and off that a tropical cyclone could develop from a tropical wave nearby the Cape Verde islands once it begins to approach Florida, this is supported by the CMC but both turn it out to sea and the ECMWF 12z run dropped the system altogether. However folks, everything is looking likely that once we get into August things will be busy, on pair with last year. It is likely that next month we will see a Major hurricane, perhaps two, and some might even threaten the USA. The pattern in place is one that reflects seasons like 2008, you have a cool tongue of sorts situated off the coast of the US that is reflective of previous destructive seasons. There is persistent ridging that was similar to what was in place last year, but that could mean if its still around it will place storms farther East more westward if a trough is not there to pull it out to sea.

As such, keep your eyes peaked the next few weeks.

I will have a special update if Bret becomes a Hurricane.

CybrTed

SPECIAL UPDATE Tropical Depression two forms 7/17/11

By: CybrTeddy, 8:41 PM GMT on July 17, 2011

Good afternoon and welcome to my SPECIAL Tropical Weather update for Thursday, June 17th 2011. Well folks, 98L has become Tropical Depression #2, a lot earlier than I was expecting. Tropical Depression #2 is located at 27.5°N 78.2°W, maximum sustain winds are at 35 mph and pressure is at 1010 mb. The depression is currently moving south at 2 mph, and is expected to turn around and head north.

BULLETIN
TROPICAL DEPRESSION TWO ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL022011
500 PM EDT SUN JUL 17 2011

...TROPICAL DEPRESSION FORMS JUST NORTH OF THE NORTHWEST BAHAMAS...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...27.5N 78.2W
ABOUT 100 MI...165 KM NW OF GREAT ABACO ISLAND
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...S OR 180 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...1010 MB...29.83 INCHES



(fig 1. Latest image of Tropical Depression #2)

My predictions at this time remain unchanged, though now I think TD2 has a good chance of peaking out at 65 mph if it begins to work at it. Satellite as posted shows convection building over the center of circulation in an organized manner and the recon is still out there. A Tropical Storm Watch is in effect for the Grand Bahama Island and surrounding islands. This watch will likely be upgraded to a warning.


(fig 2. Forecast track of TD2.)

CybrTed

98L becoming better organized off Florida 7/17/11

By: CybrTeddy, 4:54 PM GMT on July 17, 2011

Good afternoon and welcome to my Tropical Weather update for Sunday, July 17th, 2011. Right now our main area of interest continues to be 98L, which overnight has become much better organized and appears poised to become Tropical Depression #2. 98L is a trough split cyclone that developed from a positively tilted trough which stalled out in the Tropical Atlantic. Now what sometimes happens is that these troughs can sometimes split out a low pressure center, usually in the area where 98L is developing now. Satellite shows that 98L is either fully detached or mostly detached from the trough it split from and is beginning to undergo cyclongenesis. Obs from the surrounding areas show pressures in the 1010-1012 range, fairly high but I was expecting this system to have high pressures due to the higher pressure around the system.

(fig 1. View of Invest 98L)

(fig 2. Latest ASCAT pass of 98L revealing a circulation.)

Run down of the models & my predictions.
The models have done, very poorly with this system. None of the models have and still don't initialize a closed low where 98L currently is, this is a major factor for development/no development, so they get a failing grade for predicting genesis. Now, what they are all indicating is that the ridge to the north will begin to erode and cause 98L/''Brett'' to lift north and whatever intensity it may be and head towards South or North Carolina, then heading out to sea. This is a reasonable scenario to me, and is supported by most of the models. However at this time 98L continues to drift SW, the longer it drifts SW the more likely it could shift to a different path. Intensity is just as tricky to predict, right now 98L's LLC is sheared, you can tell that by visible that the circulation is on the northern edge of the convection. Shear is at a marginal 20 knots, but will decrease to 5 knots as the days go on. 98L is over 30C waters, something very dangerous but I do not think 98L will become a powerful system due to shear will probably still be effecting the system, and it is very rare to get a powerful trough split cyclone - last one as it was, was TD5 from last year.

(fig 3. Latest spaghetti model runs.)

(fig 4. Latest intensity predictions.)

I will have a special update today if the recon currently en-route finds a Tropical Depression or Tropical Storm Bret.

CybrTed

98L off the coast of Florida a possible threat 7/16/11

By: CybrTeddy, 5:58 PM GMT on July 16, 2011

Good afternoon and welcome to my tropical update for Saturday, July 16th, 2011. Today's update will focus a surface trough associated with a weakening front off of Florida that the National Hurricane Center/NRL has just dubbed Invest 98L. 98L is currently located at 300N, 791W with a fairly high surface pressure of 1014 mb. This is because 98L is embedded within a high pressure area, causing surface pressures to seem high. In truth, if it wasn't it would probably be around 1010 or 1009 mb. Maximum sustained winds aren't impressive either with 25 mph winds, and upper level conditions are marginal at best. 98L also has no model support for tropical development, but the models have been hinting at this setup for a few days now.

(fig 1. NRL image of nearly declared invest 98L)

Model indications and personal forecast.
There really isn't anything strong from the models, but they all show increased vort associated with 98L and lower surface pressures. This is going to be drifting perhaps nearly stationary over the Gulf Stream, which is well above average for this time of year. The latest ASCAT run and obs from Florida and surrounding areas indicate there is a developing surface low, but very limited convection.

(fig 2. SST images as of current.)

Often, with trough split disturbances developing once they begin to split from the trough they look quite sad in satellite presentation and a lot of them just die out without further development, we'll see if that's the case. The GFS sends this into Florida by about 72 hours, so its going to have more than likely enough time over water if its going to try to do something, which is where it gets iffy. One problem is also that the fact this has a closed low, none of the models with the exception of the non-tropical NAM which does attempt to develop this showed that in the initial conditions, which means we're going to have to take the models with a grain of salt this time around which is exactly what the NHC is doing. The NHC right now has planned for a recon into the system tomorrow.

(fig 3. GFS showing a low off the Florida coast by 72 hours)

CybrTed

Watching several areas for Tropical development - none a threat 7/14/11

By: CybrTeddy, 6:58 PM GMT on July 14, 2011

Good afternoon everyone and welcome to my tropical weather update for Thursday, July 14th, 2011. Right now there's a few areas worth watching, as expected yesterday Invest 97L moved inland with no development, but one area worth watching is the SW Caribbean. As of this blog post, the NHC has hatched a yellow circle in the SW Caribbean with a 10%, citing that development if any will be slow to occur. CIMSS 850 mb vort reveals some cyclonic turning associated with this system. This area of cloudiness and thunderstorms is moving stationary - slowly westward at about 0-1 knots, so it will be over water through the next few days. Will it have enough time though? That is the question. Once again, it appears very likely this system will be forced westward by the strong ridge stationed over the central United States.

Another area we are watching is off the coast of the United States. A positively inverted trough has moved off the coast of the United States and is generating some cloudiness and thunderstorms. It is possible as this trough moves forward in the timeline it could get stuck between the two ridges and the southern portion of the trough to get 'split' off and perhaps undergo cyclongenesis. I do not think this will happen though as trough splits are often very delicate situations, which is why they're not all that common and the last one to happen was TD5 in August 2010.

(fig 1. The Tropical Atlantic as of this blog post.)

Run down of the models.
The GFS is at this time the only model showing cyclongensis of any sort. The 12z GFS run was very interesting.
Our SW Caribbean system spins up into a 1005 mb low, probably a TD or minimal TS. This system moves into the EPAC without any further development in the Atlantic side while becoming a strong system in the EPAC. But what the model does show is that we're soon going to have to look towards the CATL for development, in the very long range it shows a tropical cyclone developing from a tropical wave - our first Cape Verde system of the year. Will this happen? No, it will not given its 384 hours out but it does show that a pattern shift is happening and we must be cautious as things will be getting very active soon.


As always, I will keep you updated.

CybrTed

SPECIAL UPDATE 97L in the Bay of Campeche 7/13/11

By: CybrTeddy, 2:47 PM GMT on July 13, 2011

Good afternoon and welcome to my special update for Wednesday, July 13th, 2011. Once again the Bay of Campeche has proven how well it can spin up systems and we now have a borderline Tropical Depression in the Bay of Campeche. Satellite reveals the circulation is very well defined, with deep convection and spiral banding. This is, with the exception of time and persistence, more than likely a Tropical Depression and if it can keep going overwater for the next 3 hours or so, we may see the NHC classify it as such. However, that's the main problem - how much time it has over water. 97L only has 3-4 hours at most over water, its close to the coast already and its moving at nearly 18 mph. If it was moving at 3-4 mph it would probably become a moderate-strong Tropical Storm before landfall.

(fig 1. 97L churning in the Bay of Campeche)

I do not think that 97L will become Bret, and might not even become Tropical Depression #2 ''officially'' but its either very close or already a Tropical Depression. 97L is without a doubt our most organized invest this season and when it makes landfall, it will either be AL02L or very close to that status. At most, if it gets classified within the next two hours it could make it to a 40 mph Tropical Storm, emphasis on the 'could', but I do not think that will happen. This will more than likely be my only update on 97L unless its classified. In that event, I will post a 2nd special update.

CybrTed

Tropical trouble possible off Africa 7/11/11

By: CybrTeddy, 2:12 PM GMT on July 11, 2011

Good afternoon and welcome to my tropical weather update for Monday, July 11th, 2011. Right now looking at the Atlantic there is hardly much going on, there is a flareup in the monsoonal trough in the SW Caribbean with a small area of rotation. However this vort max is expected to move inland due to a strong ridge that we saw with Arlene still in place and move into Central America with no development anticipated. There is a tropical wave approaching the islands with a 10% chance of development on the NHC site, however satellite already shows it falling apart and development is not expected. Right now, we'll be focusing on two areas to watch over the coming days, the SW Caribbean and for the first time this season - off Africa.

(fig 1. The current view of the tropical Atlantic)

Run down of the models & predictions.
First, I want to talk about what the latest GFS is showing, the 06z run, which is showing an interesting setup. The GFS was showing at first a tropical storm developing in the SW Caribbean and moving inland into Central America. It has since dropped this development, but its showing a period that there will be several strong waves emerging off Africa. The first is currently over Western Africa moving westward. In 84 hours, it shows a very strong wave emerging off Africa and gradually begin to develop into perhaps a tropical depression. The 06z run was much weaker than the 00z model run of this, which showed a tropical storm attempting to form in the Central Atlantic, and at this time however only shows a depression at most. After that, there are two well organized waves that emerge right behind this system.

(fig 2. 06z GFS 120 hrs out - wave off Africa worth watching)

At this time, it is only the GFS showing any sort of development off Africa. Remember, the GFS caught Arlene first a few months ago and if you have a good memory even you'll remember that in 2008, the GFS caught the wave that became Bertha back in July 2008 first. I suspect that this could very possibly happen, if the GFS remains very consistent with this happening and models start jumping on board. The GFS is also showing this happening in a relatively short term, in 84 hours we could be dealing with a system. I'm quite skeptical of this occurring however, until at least the CMC and NOGAPS gets onboard with the GFS for any sort of development. However, this is showing to us that we're in for a very active Cape Verde season which is usually the case for neutral seasons like this.

(fig 3.image of the tropical wave that could be worth watching.)

We'll keep an eye on it.

CybrTed

96L in the Gulf, CATL disturbance 7/7/11

By: CybrTeddy, 2:12 PM GMT on July 07, 2011

Good morning and welcome to my tropical weather update for Thursday, July 7th, 2011. Overall the tropics are fairly active with 96L in the Gulf of Mexico currently located at 24.9N 83.7W, with maximum sustained winds holding at 30 mph, and a CATL disturbance just to the east of Northern South America. At this time, neither area is well organized and both have limited to no model support, though its worth watching.

(fig 1. Invest 96L)

Rundown of the models.
The models aren't very strong on this system, all but the CMC are showing an open wave tracking through the Caribbean and no development coming from 96L. The CMC however, shows 96L becoming a Tropical Depression in the Gulf before making landfall in Florida, skirting the Eastern Coast of the USA while becoming a 999 mb Tropical Storm. This isn't very likely, even if conditions support it.

(fig 2. CMC model run with 96L)

My forecast for track and intensity.
In my opinion, neither system is very likely to develop at all. For 96L, it should remain a non-tropical low if it even does try to get organized and bring beneficial rains for Florida. There is a possibility however as indicated by the CMC that if this gets over the warm waters of the Gulf stream we could see Bret from 96L, but that has a very low chance of happening in my opinion. For the CATL wave, right now its currently embedded within the ITCZ, which is helping its divergence and convergence, however it needs to separate from the ITCZ in order for any development to really take place. ITCZ splits are often very dangerous in July, they can sometimes lead to dangerous systems in the Caribbean however I do not think that's going to happen. Right now it will be interacting with the TUTT which will be providing 20-40 knot shear over it once it gets into the Eastern Caribbean which should limit any development. Another problem it has is South America, it needs to make a hard turn to the NW to avoid it completely which at this time doesn't appear likely at all.

(fig 3. 96L's model run tracks, most show it moving inland)

CybrTed

Atlantic is dead asleep - GO ATLANTIS! 7/5/11

By: CybrTeddy, 12:39 AM GMT on July 06, 2011

Good evening and welcome to my short update for July 5th, 2011. There's nothing at all going on in the tropics, though on the EPAC side things are a little active. Looking out in the Atlantic the only thing that might merit some blob watching is a tropical wave near the Bahamas that is generating some showers and thunderstorms. It is interacting with a short wave TUTT to the north that is causing 20-40 knot shear. This moisture should move over Florida by Friday. The CMC and NOGAPS are interesting with this wave, as both show it developing into a cyclone off the coast of the USA in a few days. I don't think this is going to happen, as they haven't been really consistent and the GFS & ECMWF aren't being aggressive at all with development. So, in short the tropics are quiet and no development is expected in the next 108 hours.

(fig 1. Tropical Atlantic as of this hour)

Atlantis - the final shuttle.
You know, the space shuttle has always been to me something of great personal importance. I've had family who lived by and worked on the space shuttle, even knowing the crews. I myself have seen shuttle components, such as all 3 of the Multi-Purpose Logistics Modules (MPLMs), Node-2, Columbus, Kibo, Node 3 all up close, and I've also had the privileged of seeing Space Shuttle Discovery set atop LC39A for its launch back in May 2008. The thing that's struck me the most about the Space Shuttle is not only its size and marvel but how dedicated the people are that work on it. Even now, when faced with a pink slip and an uncertain future, the guys and gals who go out and work on the shuttle still twink Atlantis to perfection, and ensure no slip up. Systems are rechecked and rechecked, and backup systems - and even backup backup systems. For example, on April 29th, 2011 NASA scrubbed the launch of Space Shuttle Endeavour, because a heater on a triple-redundant system failed. They didn't want a unlikely, worse case scenario happening to Mark and his crew.

(The STS-135 patch)

The space shuttle was born out of the competition of the Cold War to launch satellites, build space stations, and service orbiting telescopes. The first launch, STS-1 with Columbia, was something of magnificent joy to everyone who saw it. Now, the shuttle still brings that joy to people who see it. I'll have the personal pleasure to see the final space shuttle flight on Friday (assuming the weather cooperates), and I'll be able to post pictures. Atlantis will carry a stuffed a MPLM stuffed full of food and equipment for one year on the International Space Station. The STS-135 is the 135th, and final space shuttle mission, a 12 day mission that will see one space walk and the MPLM installed on the Node 2 Nadir port. Atlantis will then place the MPLM back into the cargobay and undock with the ISS. When Atlantis lands at Kennedy Space Center (or Edwards Air Force base) it will end an era of cooperation, and dedication. Atlantis docked 9 times to Mir and 12 times to the international Space Station. It was the last shuttle to service the Hubble Space Telescope too. In this sense, given the International Space Station was an international effort its appropriate Atlantis gains the honor being the last space shuttle to soar in space. I'll personally never forget the space shuttle, and all the glorious things it did for us and our country. All the scientific benefits it has granted us have done us well, and done us proud but in every aspect the last 30 years the space shuttle has seemed to been taken for granted by the American public. I can assure you however that history will judge the Space Shuttle as favorably as it did the Apollo program, we'll look back on the shuttle and say 'we really did that? wow!'.


Godspeed Enterprise, Columbia, Challenger, Discovery, Atlantis, and Endeavour.


(STS-1, Young and Crip)

(STS-135, Fergie, Hurley, Sandy, Rex)

High Flight

Oh! I have slipped the surly bonds of earth
And danced the skies on laughter-silvered wings;
Sunward I've climbed, and joined the tumbling mirth
Of sun-split clouds - and done a hundred things
You have not dreamed of - wheeled and soared and swung
High in the sunlit silence. Hov'ring there
I've chased the shouting wind along, and flung
My eager craft through footless halls of air.
Up, up the long delirious, burning blue,
I've topped the windswept heights with easy grace
Where never lark, or even eagle flew -
And, while with silent lifting mind I've trod
The high untresspassed sanctity of space,
Put out my hand and touched the face of God.
Pilot Officer Gillespie Magee
No 412 squadron, RCAF
Killed 11 December 1941


CybrTed


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.