Leslie Could Track Close to Bermuda Late Next Week
TS Leslie remains just below hurricane intensity as a fairly constant northerly shear pattern is in place, keeping the deep convection from wrapping around the low level center. It is quite remarkable how hostile the deep tropics have been again this season which in turn has meant that we’ve had no major hurricanes as of yet (no category three or higher hurricanes). However, the global models all show Leslie moving in to a more favorable environment over the next several days and it should become a fairly strong hurricane at that time. Ocean temps are warm and the wind shear is forecast to relax considerably.
The steering pattern is complex and could have some big implications for Bermuda as the coming week unfolds. Right now, the storm is moving along to the northwest at a fairly good pace, 15 mph. This will soon change as the flow in the atmosphere changes and Leslie gets stuck in the middle of this pattern change. There is a chance it could just meander out in the Atlantic for a couple of days. How close this happens to Bermuda remains to be seen but there is a chance that Leslie could impact the island beyond the NHC five day forecast period. Interests in Bermuda should just keep an eye on the future predictions for Leslie this coming week.
Surfers should also keep an eye as well since the farther west Leslie tracks and the stronger it gets, the more long period swell action the East Coast will see. We’ll know more about what to expect later this week but it looks like there will be some increase in the surf along parts of the East Coast by next weekend.
The remainder of the Atlantic is quiet in terms of any other issues to be concerned about. I think we are heading for a lull in the action once Leslie moves out but that could take a while as mentioned above.
I will have more here tomorrow morning.
Kirk and Leslie both headed out to sea
It’s back. The seemingly permanent weakness or hole in the Atlantic ridge that has turned numerous hurricanes away from the United States since 2008. Obviously Isaac was able to sneak in underneath; as did Irene last year. But Leslie? It will not. The pattern is such that there will be a trough too far east over North America for Leslie to make it much past 60 W longitude.
With the forecast calling for Leslie to become a hurricane, it should still produce a few days of nice long period swells for surfers to enjoy. Any increase would be nice I suppose. But that should be the extent of it as the global models are firm now in showing a turn away from the U.S. with the track.
Kirk is also heading out farther in to the North Atlantic and will lose its tropical characteristics within a day or two as waters underneath its circulation gradually cool.
The rest of the tropics are quiet and even in the east Pacific there are no areas of concern this weekend.
I am back at home in North Carolina and will resume the daily video blog for our app. On Monday, I will have a longer write-up about Isaac as well as announce plans for our first DVD since 2008. Have a great weekend!
As the remnants of Isaac dump rain across a good deal of the mid-Mississippi Valley, causing even more problems along the Mississippi River downstream, we now begin to focus more on TS Leslie and its future over the next week to 10 days.
The NHC track has indicated a turn to the north near 60 degrees west longitude; just west of there to be exact. However, I think this is going to change in the coming days as indications are that there will be stronger Atlantic ridging to keep Leslie moving more west than north. How far west and for how long remains to be seen and it is entirely possible that a trough of low pressure in the steering currents of the atmosphere will come in and dig east and south just enough to scoop Leslie up and turn it out to sea.
GFS 500mb Chart Showing Leslie SW of Bermuda in 8 Days
If we look at the 6Z GFS model at 500mb, about the middle steering layer, we see Leslie very well as that dark red ball to the southwest of Bermuda and that 588 “oval”. That is a height line which is kind of like a contour line on a topographic map. This shows that the Atlantic ridge is quite strong and won’t allow Leslie to turn north in to. Leslie is akin to a small water balloon while the ridge is akin to a huge, more dense water balloon. The storm has to go around the ridge and look for a weakness. We heard this a lot about Isaac and when it might turn north. The ridge turned out to be stronger than originally forecast by the global models and Isaac moved much farther west in to the Gulf as we all know now.
Since Leslie is forecast to be a hurricane, and likely a strong one too, its proximity to the United States around day 8 and beyond means an increase in long period swells is coming. For surfers this is great news. For swimmers, especially those with little experience in the ocean, this can mean dangerous surf conditions are in store. We’ll address that as needed down the road. Right now, the upcoming holiday weekend will be JUST FINE and there are no worries about Leslie anywhere. But later next week, we will need to watch and see how much that Bermuda High expands and thus how much of a correction west the models indicate.
Elsewhere, Kirk is a solid hurricane but is of no concern to land areas at this time.
In the eastern Pacific, hurricane Ileana will turn west under a strong ridge of high pressure and move away from the Mexican coastline while we monitor another large area of disturbed weather farther south and east of Ileana for possible development.
I am currently heading home from our Isaac mission and will have regular blog posts throughout the weekend ahead.
A Very Busy Atlantic Basin
Isaac is now well inland over Louisiana but it is still causing significant problems for the areas that have dealt with its rain, wind and storm surge over the last few days. There have also been tornadic storms accompanying some of the rain bands as well. It will take a few more days for the remnants of Isaac to finally clear the pattern and it will likely do so by dumping a lot more rain over a wide swath of the eastern U.S. In fact, interests along the entire cone of Isaac’s forecast track need to be on alert for rapidly changing weather conditions over the coming holiday weekend. This is especially true in the mountainous areas that Isaac’s moisture will pass over as it heads east and even south of east.
Elsewhere we have hurricane Kirk and TS Leslie to keep us busy over the coming days. Kirk is of no threat to land areas right now and Leslie will probably turn north within 10 degrees of 60 W longitude, but you never know this time of year.
The next 30 days are the most active of the hurricane season climatologically speaking. This season has proven to be quite a bit more active than earlier thought by forecasters and I think the increase that NOAA indicated in their August update is coming to fruition. Isaac proved once again that much needs to be done to help the general public realize that hurricanes are not points on a map nor do they follow some set of rules laid out by man. Their effects can be far-reaching and extend well beyond the wind seed or category assigned to them. As September arrives, keep preparedness and education on your mind – you never know when that can pay off in helping you to deal with the likes of Isaac.
I am on the road heading back home from the MS Gulf Coast after a very successful field mission with Mike Watkins and Kerry Mallory. Once again, we met a great group of very kind and helpful people, some even in the middle of the wind and rain who just wanted to help us with directions. It is amazing how the Internet connects us now, no doubt about that.
I’ll have regular blog posts again, perhaps many per day. That being said, I plan to write one addressing our iPhone app and what went right, what went wrong and how we plan to make it the success that I know it will be.
I’ll post more here tomorrow.
5 Day Rainfall Forecast from HPC
The field mission to cover Ike along the Gulf Coast is nearing its end. I will write up a more thorough look back at what all we accomplished, and what still needs to be done, in a later post.
Right now, Isaac continues to dump heavy rain on portions of the lower Mississippi Valley. This huge envelope of tropical moisture will spread northward and eventually turn northeast, bringing heavy rain to a large chuck of the eastern United States. Just look at the HPC rainfall forecast and you’ll see what could be coming over the next five days as Isaac leaves the coast and finally moves inland.
For areas that have not seen heavy rain in quite some time, keep in mind the risk of flooding and take the necessary precautions. It mostly has to do with common sense. Follow that, and you will be safe.
As for Mississippi and Louisiana, Isaac will live on long after it moves away from the region. The clean up and recovery phase, something all too familiar in this area of the country, will commence. Some locations were hit harder than others. News reports are full of more sad stories of flooding and loss but the effects, as we well know, could have been far worse. They were far worse exactly seven years ago today.
The rest of the tropics remain busy as we round out August. Kirk is no threat to land and 98L will almost certainly be a depression tomorrow. We’ll watch it and see what its future holds. At least the coming weekend will be nice for coastal areas with no threats from the tropics to worry about.
We had a very successful field mission and I look forward to sharing much of what we learned, the data we captured and some incredible video with you over the coming days. Mike, Kerry and I would like to thank all of the people who watched our live streams and for the support that we received from the great people of Mississippi once again. While it’s tough to see you all have to deal with this on a regular basis, we appreciate you extending a helping hand to us as we do our work to better understand and report about these incredible weather events. I’ll have regular blog posts again beginning tomorrow afternoon.