Karl to be focus of attention over next several days

Satellite image showing TS Karl which is currently sheared quite a bit along with a new tropical wave emerging from the coast of Africa. Click for full size image.

Satellite image showing TS Karl which is currently sheared quite a bit along with a new tropical wave emerging from the coast of Africa. Click for full size image.

The main area to watch this weekend and in to next week will obviously be tropical storm Karl. While the odds are in favor of it turning away from the United States at some point, there is nothing that tells me this is a sure thing.

Right now, Karl is dealing with strong upper level winds and a dryer than normal mid-level portion of the atmosphere. Despite these inhibiting factors, deep thunderstorms are trying to develop in association with the vigorous low level center. Each time a burst of convection manages to pop up, the strong winds blowing against the storm quickly removes the clouds and pushes them back to the east. This bursting pattern as we call it will not lead to any appreciable strengthening but will keep the storm moving west and even south of west this weekend.

As we get in to early next week, both the intensity and the steering of Karl will become very important. The global models seem to be waffling back and forth between making this a hurricane and doing very little with it at all. Other intensity guidance suggests some strengthening next week but the extent of that is still an unknown. Water temps are plenty warm but the upper level winds are questionable. The recent uptick in shear across the Atlantic could remain in place, keeping Karl weak. If the pattern changes and the shear relaxes then it’s likely that Karl will become a hurricane.

As of now, it looks like the Lesser Antilles will not have any direct impacts from Karl. It should track well to the north of the Caribbean and be positioned somewhere between Bermuda and Puerto Rico in about five days. After that, it’s a question of whether or not a trough of low pressure passing by to the north of Karl will be enough to lure it out and drag it back in to the open Atlantic. It stands to reason that the weaker Karl is in to next week, the further south and west it will track. Then, as the trough goes by it misses Karl and we’re left with wondering what happens next. Seems like we’ve done this before once or twice, eh? So for now, we shall watch and just keep track of it with no issues for land areas seen anytime soon.

Meanwhile the weakening low pressure area that was once TS Julia continues off the Carolina coast. I see no reason to be concerned with this making any dramatic comeback but it’s out there, sheared to bits, but something to at least keep an eye on this weekend.

The only other area of interest is a tropical wave coming off of Africa now. It too could develop in the deep tropics as it moves generally westward. Interests in the Cape Verde Islands should be prepared for passing squalls and gusty winds as the tropical wave energy passes by this weekend.

I’ll have a video discussion posted here and to our YouTube channel as well as our app by later this afternoon.

M. Sudduth 9AM ET Sept 17

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Tropical wave in cental Atlantic a sign of what’s ahead

Tropical Weather Outlook map from the NHC showing area of interest in the central Atlantic

Tropical Weather Outlook map from the NHC showing area of interest in the central Atlantic

Not much going on in the tropics since Arthur earlier this month. This is typical for July which is usually a very quiet month in the Atlantic Basin.

In fact, we did not have any tropical waves to flare up worth mentioning until yesterday when the NHC issued an outlook for one in the central Atlantic. It rolled off of Africa a few days ago and has a low pressure area associated with it at the surface. Water temps are warm and overall, environmental conditions are generally favorable for development right now. However, this is likely only temporary as it looks as though conditions will not be so great for development as the week wears on. It’s just too early in the season yet for robust Cape Verde tropical waves to get going this far east. We’re still looking at another month or so before that happens.

The presence of this system does remind us of what could lie ahead. As I mentioned, July is usually not very active, especially in the deep tropics. Once we get in to mid to late August, conditions change and we begin to see more and more active tropical waves moving west from Africa. At that point, it will come down to upper level winds and, perhaps more importantly, instability in the atmosphere. If the mid-levels of the atmosphere are too dry with lower humidity value than usual, then the tropical waves will struggle to develop deep convection and will remain weak. On the other hand, if moisture levels are where they should be or are above average, then we would likely see a very busy August and September.

I believe that much will depend on the situation with the El Nino which was forecast to be coming on quite strong by August. As it turns out, there is barely any El Nino to talk about, especially in the central regions of the tropical Pacific. It just never made it and what warming there was has all but vanished. However, the water just west of South America, extending westward for several hundred miles, is still quite warm compared to normal. This could have just enough negative influence on the Atlantic side to help keep the peak months of August-October quieter than normal.

One thing I will be watching for is how much, if any, cooling takes place in this region of the Pacific. There are indications that we could see a considerable drop off in the surface temperatures of this area and if this happens, I suppose it could remove at least a portion of the negative influence for the Atlantic Basin. It’s just so complicated and hard to tell if one puzzle piece really makes that big of a difference considering how the other pieces fit together and interact with each other.

For me, the tropical wave that the NHC is talking about this morning is a sign that we are approaching the peak months of August-October. Thus it is a good time to remind you to be aware and prepared. Arthur was an interesting event in that it was so early in the season and it did not fall apart at landfall – instead, it continued to strengthen despite its close proximity to the North Carolina coast. If that is the way things will go this season, it won’t matter much if tropical waves develop far out in the Atlantic. What matters are the ones that would do so close to land, leaving little time to react. We’ll see how things shape up over the coming weeks but August is just around the corner and from there on, at least from a climatological perspective, the season should become more active. Time will tell just how active, that is the only certainty at this point.

I’ll have another blog post here tomorrow morning.

M. Sudduth 10:24 AM ET July 21

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July likely to end without much to talk about

East Atlantic tropical wave with low chance of development

East Atlantic tropical wave with low chance of development

Even though the NHC does have an area outlined in yellow today off the coast of Africa, I think that July will finish up without much to really be concerned about.

There is a formidable tropical wave located just off the African coast today and the GFS model in particular has been suggesting that this would develop. However, conditions in the tropical Atlantic are marginal at best with plenty of mid-level dry air present and a distinct lack of upward motion. As such, I think that this tropical wave will have a tough time developing much in the coming days. It is still July and climatology is a big part of the equation. There is a reason why we do not see much development in the tropical Atlantic this time of year – give it a couple of more weeks and things will change.

In the east Pacific, the NHC is monitoring invest area 98-E for slow development over the next several days. In this case, conditions are fairly favorable but what ever comes of it will move away from Mexico and not pose any threat for folks there.

In other news, our app, Hurricane Impact, is almost ready for Android devices. I am going to be testing it myself later today and will have a good idea of when we can expect it to hit the Google Play store. The app will feature the same features as our iOS version: daily video blog, HurricaneTrack.com blog, live Surge Cam, live weather data feed, field mission video blogs, our own tracking maps along with Twitter and Facebook integrated in to the app. It will also feature content from Mike Watkins of Hurricane Analytics which will be a new addition to our iOS version as well in the coming weeks. We are excited to have both platforms covered and know that the Android users out there will be equally excited. As soon as I know the release date, I’ll post a special blog with the announcement.

Enjoy the quiet pattern while it lasts. August is approaching and a month from now, I would venture to guess that we’ll have a lot to talk about.

M. Sudduth

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NHC monitoring tropical wave in western Caribbean Sea

This tropical wave may develop next week in the Bay of Campeche

This tropical wave may develop next week in the Bay of Campeche

Just when it looked like things would remain quiet for a while, things change. The NHC is watching an area of showers and thunderstorms, associated with a tropical wave, as it moves slowly through the western Caribbean.

As of this morning, the NHC was giving the area a 20% chance of developing over the next 48 hours. In looking at satellite images of the region, there is definitely an increase in deep convection associated with the system.

Water temps in the area are plenty warm but vertical wind shear, the difference in wind speed with height, is running above average right now. This means that upper level conditions are not quite there yet to allow for much development. However, the NHC notes that conditions may improve over the next few days as the tropical wave moves over Central America.

Global computer models are not too ambitious about development though the GFS in particular does show a well defined low pressure area in the southern Bay of Campeche within three to four days. It is not unusual for tropical waves to develop in this region fairly quickly. There is something about the make-up of the area that seems to foster small but quick growing tropical cyclones.

Right now the main impact will be heavy rains spreading across the western Caribbean in to Central America. Early next week, it is possible that we will see a tropical storm form in the Bay of Campeche and so interests in that region should pay close attention to this developing situation.

The weather pattern at present does not favor this system coming north enough to affect the United States. This looks to be an issue for areas along the southern Yucatan and in to the Bay of Campeche next week.

I’ll post more in this system tomorrow morning.

M. Sudduth

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Tropical wave headed for Lesser Antilles, not expected to develop

Vigorous Tropical Wave That Will Affect the Lesser Antilles in a Few Days

Vigorous Tropical Wave That Will Affect the Lesser Antilles in a Few Days

The tropics are busy, sure, but with no threats to land, there is probably not much interest in what’s going on out there. However, we do have a tropical wave that has flared up in recent days that is bound for the Caribbean Sea.

While none of the global models develop this wave to any significance, it will likely bring a period of squally weather to portions of the Lesser Antilles in the coming days. This is probably one of the last of the vigorous tropical waves that we will see for a while as the season is progressing towards favoring the western parts of the Atlantic Basin rather than the region between Africa and the Islands.

Meanwhile, hurricane Nadine continues to move away from the U.S. and could be an issue for the Azores Islands several days down the road. In fact, the global models suggest that it will linger in the Atlantic for perhaps another 10 days. Sometimes these systems get stuck in the current pattern and can hang on for days on end.

The east Pacific has TS Kristy which is falling apart off the Baja and TD #12-E which is not expected to impact land as it strengthens some and moves generally northwest with time.

I’ll have more here tomorrow. Be sure to catch the video blog for today which has been uploaded to our iPhone app.

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