Gulf Stream aiding in comeback for Bonnie? Also, southern Gulf area to watch in coming days

Tropical depression Bonnie as seen in early morning visible satellite very near the NC Outer Banks

Tropical depression Bonnie as seen in early morning visible satellite very near the NC Outer Banks

The NHC will begin issuing advisories again on what was once TS Bonnie, now a tropical depression again very near the North Carolina Outer Banks.

It seems that the close proximity of the warm Gulf Stream has helped to refuel enough organized convection to aid in the recovery of the system. The main threat will be continued heavy rain and some gusty winds, along with locally rough seas (ocean and sound). I do believe the Hurricane Hunters will be flying a mission in to the area later today and we’ll know more about the wind field at that point. Right now, I am not seeing anything to suggest rapid strengthening though it would not be unreasonable to suggest that Bonnie could attain tropical storm intensity before all is said and done.

Unfortunately, the steering currents are still quite weak across the region and thus Bonnie will be aggravatingly slow to move out. It looks like by later tomorrow, the pesky storm system will finally move on out to sea. Until then, if you have plans to visit the Outer Banks or are there now, just keep in mind the fact that occasional bands of heavy rain will impact the area.

Meanwhile, we will soon need to turn our attention to the southern Gulf of Mexico where it looks like we may see yet another system try to develop some time next week.

Almost all of the reliable computer models are suggesting a broad area of low pressure will develop from energy piling in to the western Caribbean over the next few days. Upper level winds won’t be ideal but water temps are certainly warm enough and there is a decent chance that a tropical depression or even a tropical storm could form and head generally towards Florida.

GFS 850mb map showing energy associated with a broad area of low pressure in the Gulf of Mexico in about 5 days

GFS 850mb map showing energy associated with a broad area of low pressure in the Gulf of Mexico in about 5 days

One thing to keep in mind, the models are not indicating a very strong system, at least not yet. As an example, I have posted a pic of the overnight GFS model which shows the winds and vorticity (spin in the atmosphere) at the 5,000 foot level or what we all the 850 millibar level. This gives me an idea of how well organized or compact a given storm might be. The more round and “bundled” the energy, the stronger it is likely to be in the real world. Notice in the image, the energy is spread out over a fairly large area, not concentrated and totally symmetrical. This tells me that what ever develops could be more spread out and thus weaker than say a hurricane would be. Obviously this can change but for now, it looks like a lopsided, sheared system with plenty of heavy rain potential, which should never be underrated. From the wind and surge perspective, so far, there is not much to indicate any major issues. I will obviously continue to monitor the situation and will post regular updates here and via my daily video discussions over the coming days.

Last but not least, a tropical depression is likely to form in the east Pacific well to the southwest of Mexico over the next few days. No matter how strong it becomes, the track will be away from land with no impact what so ever for Mexico.

I’ll have more here early this evening on Bonnie and an update on the potential Gulf system as well.

M. Sudduth 8:55 AM June 2

Quiet time short-lived? Some model support for Gulf development

Substantial MJO pulse forecast by the ECMWF over the next two weeks

Substantial MJO pulse forecast by the ECMWF over the next two weeks

The rest of this week is likely to remain nice and quiet across the Atlantic, Caribbean and Gulf but once we get to next week, things could change. Here’s why…

First of all, the time of year supports Gulf of Mexico or western Caribbean development. We shift away from the Cape Verde region and the waters between there and the Lesser Antilles towards a pattern that favors development much closer to land areas. We might be seeing that come to fruition in the coming days.

The other reason I think development could happen is the progression of a strong MJO or Madden-Julian Oscillation pulse. Think of it as a period of fertility in the tropics. Instead of dry, sinking air, the MJO typically brings with it an increase in convection and a general rising motion in the atmosphere. These things are needed to even have a chance for a tropical storm or hurricane to develop.

According to the GFS and the ECWMF, the MJO is about to amplify significantly in to the phases that would, in theory, support development either in the southeast Pacific or the western Caribbean/Gulf of Mexico regions.  Water temps are plenty warm and so now it’s just a matter of watching to see what happens. So far, both the GFS and the ECMWF show signs of developing a tropical storm in the 8 to 10 day time frame. For what it’s worth, the two models are in remarkable agreement on the timing and the general placement of such development – the southern Gulf of Mexico. I usually don’t pay much attention to model forecasts beyond the 5 to 7 day time frame but when the two (rival) models are in agreement, it is worth watching a little closer.

Right now, nothing to worry about at all. It’s important to remember that we are still very much in hurricane season and it’s not over until it’s over. There are signs beginning to come in to focus that we might have one more system to deal with before all is said and done. Obviously I will keep a close eye on how things shake out over the next week or so.

I’ll have more here on this tomorrow.

M. Sudduth 8:35 AM ET Oct 14

Weak low pressure in northeast Gulf of Mexico bringing rain to FL but nothing more

Weak low pressure in the Gulf is producing rain for Florida but little else in the way of development is expected

Weak low pressure in the Gulf is producing rain for Florida but little else in the way of development is expected

The tropics are fairly quiet as we start the week. About the only area worth watching as of now is a weak low pressure and associated surface trough draped across portions of the northeast Gulf of Mexico.

There was concern late last week that we could see tropical development from this stalled out frontal boundary but it looks as though that won’t happen now. However, very heavy rain has been falling across portions of the Florida peninsula in recent days, causing flooding with the risk of more to come. Computer models generally agree that the low will move over Florida as the week progresses and as such, the chance for widespread rain, heavy at times, will be part of the forecast for the region.

Why won’t this develop in to a tropical storm?

Strong northeast flow in the upper levels of the atmosphere will likely keep the low from developing further

Strong northeast flow in the upper levels of the atmosphere will likely keep the low from developing further

Normally, low pressure sitting over water temperatures that are in the upper 80s would be cause for alarm. While the heavy rain threat is enough of a problem, it looks as though that will be the only issue Floridians face with this system. So why won’t it develop in to a tropical depression or a tropical storm? The biggest reason are the upper level winds. Right now, they are blowing over the top of the low from the northeast, pushing the deep thunderstorms or convection away from the low center itself. This does not allow the low to strengthen by way of convection wrapping around itself, allowing pressures to drop and the process to get going.

There might be a small window for the low to become better organized but the forecast from computer models indicates that the strong northeast flow across the region will continue.

The bottom line for interests in Florida, especially the central peninsula and points south to an extent, is that heavy rain is possible over the next couple of days as the low moves across. If you have travel plans, leave extra time for that and slow down during the downpours – tropical showers can be very heavy with blinding rain. Also be aware of any flooding that may take place and keep kids away from swollen ditches, creeks and rivers – remember, water is not the only danger when we’re talking about Florida and flooding.

As for the rest of the tropics? The Atlantic is mostly dead right now with a pattern in place that does not promote upward motion in the atmosphere. I do not see this changing anytime soon and so we will likely end July without any hurricanes to worry about.

In the eastern Pacific, there are two low pressure areas to monitor far from land over open water. None of the computer model guidance suggests that either will become a hurricane nor will they impact land anytime soon.

That’s about it for this Monday. I’ll have a special blog post later this week concerning our new generation of storm surge camera systems and how we plan to utilize them when the next hurricane makes landfall along the U.S. coast.

M. Sudduth 12:10 PM ET July 27

Several areas to talk about

NHC five day outlook indicates several areas to monitor

NHC five day outlook indicates several areas to monitor

The tropics are quite busy with one hurricane and three additional areas to watch in the coming days. Let’s begin with Cristobal…

As of this morning, hurricane Cristobal had winds of 80 mph. Not much change in strength is expected although it could become a little stronger before undergoing transition in to a powerful extratropical storm over the North Atlantic. In fact, interests in the United Kingdom should keep watch over the post-tropical version of Cristobal as it tracks across the Atlantic over the next several days.

In the Gulf of Mexico, the NHC has increased slightly the chance of development for what is now invest 98L. Deep convection developed over night around the northern part of the broad low pressure area. However, upper level winds are quite brisk out of the west and west-southwest and this is helping to push the convection away and not let it organize much around the low. In any case, there is a small window of opportunity for this system to develop further before it moves inland over south Texas later tomorrow.

The biggest impact from 98L will be periods of heavy rain and occasional gusty winds. Local effects such as an increase in waves with any of the heavier thunderstorms will impact boating interests. Hopefully some much needed rainfall will come out of this for parts of south Texas – just as long as it’s not too much of a good thing all at once.

A Hurricane Hunter crew is scheduled to investigate 98L later today if conditions warrant. We’ll know more then about the structure and wind field but again, this is only if the NHC feels the flight is needed.

Farther east in the tropical Atlantic, what was once invest area 97L has now become a non-issue, for now anyway. It appears that the tropical wave energy is likely to to track in to and across the Caribbean Sea over the next several days. Computer models are indicating the chance of development either in the western Caribbean or perhaps the southern Gulf of Mexico early next week. This will be something to keep an eye on but for now, the tropical wave is not organizing but it will bring a brief period of squally weather to parts of the Lesser Antilles as it moves through over the next day or two.

The last area to discuss is a tropical wave forecast to move off the coast of Africa in a day or so. Most computer model guidance suggests that this will develop rather quickly and should become a tropical storm over the far eastern Atlantic. I do not know how many people actually live in the Cape Verde Islands but it appears that they will be impacted by this strong low pressure area and could experience tropical storm conditions as it passes by. Beyond that, it is obviously too soon to even speculate on where it may end up. However, most of the time when something develops that far east, it has no trouble finding a weakness in the high pressure area over the Atlantic and turning north and eventually out in to the open Atlantic.

So there is quite a bit going on as we end August. Things can change quickly this time of year so keep up to date with the latest. I’ll post updates on Twitter as they come in and will have another full blog post either late tonight or certainly by early tomorrow morning.

M. Sudduth 10:00 AM ET Aug 27

Small window for small system to develop in extreme southern Gulf of Mexico

Invest area 90L slowly trying to organize in the extreme southern Gulf of Mexico

Invest area 90L slowly trying to organize in the extreme southern Gulf of Mexico

The only area of interest in the Atlantic Basin is 90L, situated way down deep in the southern Gulf of Mexico.

It is a small weather feature but has a chance, perhaps due in part to its small size, that it could become a tropical depression later today. Upper level winds are not especially favorable but it appears that some deeper convection is developing near the center. Water temps are quite warm and so it won’t take much for it to acquire enough organization to perhaps become the first tropical depression of the 2014 season.

The main issue has been and will continue to be rain. Fortunately, with the area being quite small, the impact to land will be limited. Nevertheless, heavy rain over portions of Central America will be something to contend with as this system festers in the Bay of Campeche.

Most computer guidance suggests that it will eventually move inland over southern Mexico, probably well south of Tampico. Even if it is able to attain tropical depression, or even become a tropical storm, it will not have much time to strengthen before upper level winds become too hostile and land interaction becomes a factor. Again, the main impact will be heavy rain and this can cause loss of life and damage due to mudslides and flash flooding.

Elsewhere, the Atlantic and east Pacific are nice and quiet as we enter the first full weekend of the hurricane season.

I will have an update here early this evening once more data becomes available on 90L – including the chance that recon will fly in to investigate.

M. Sudduth 10:11 AM ET June 6