So, I haven't seen a hurricane thread here since Irene of last year, so perhaps it's time to start one up given that we're only half way-ish through the Atlantic season.
Unless it's quoted as being from another source, all information in my posts is my own personal opinion and I fully admit I'm a complete amateur at looking at this information. I could, and likely probably will be wrong in some, many, or all of my assertions. Any decisions you make personally are your own and the only place you should really turn for official information in life or death situations is the NHC or your own local weather service.I mostly pay attention to the Atlantic basin, but I'll try to keep an eye on the Pacific as well for any interesting developments. My information sources are a bit lacking in that area though, so if anyone notices anything pop up, please say so.
Also, for the most part, I'll forgo graphics in this thread as WUnderground does it so well already, and if you're interested at all, check out Dr. Jeff Master's Blog and their tropical weather section at
http://www.wunderground.com/tropical/ The only thing they don't have there is an easily viewed ECMWF model, but that's due to ECMWF's odd licensing and their refusal to let their models be combined with any others. It's still a good model though, and their site can be found at
http://www.ecmwf.int/ (It is hard to navigate though.)
Atlantic:
So far this season we've seen:
Alberto
Beryl
Chris
Debby
Ernesto
Florence
Helene
Gordon
IsaacJoyce
Joyce has faded away to a gusty breeze, Isaac still stands as a serious threat in the Gulf of Mexico
Isaac however has been a bit of a puzzle the last few days. Currently classified as a tropical storm. The models can't seem to get a track on things as he hasn't wanted to form a well defined center. For a while it almost seemed as if there were multiple cyclones within a larger circulating structure, but that's mostly dissipated and we've got a somewhat strong set of thunderstorms with decent circulation that sit ready to reorganize into something more like a normal cyclone in the next day or so. At the moment, the cone includes Hispanola, Cuba, large portions of Florida, and looks to be headed almost anywhere from Texas to Northwest Florida after that.
There is a high pressure ridge that is currently moving into the Gulf, but it's yet to be determined if Isaac will turn north fast enough to be seriously affected by it. The farther it travels the weaker it will get. An immediate north turn could have Isaac slam into it like a wall and divert sharply northeast or west, however at Isaac's current predicted path, I'm not sure if it will reach the ridge before is spreads out too much. It will have some effect for sure, but it's hard to tell if it will only be a slight curve or a sharp turn, or whether it will find a break in it to funnel through.
The models started last night and this morning wanting to put it up one of the coasts of Florida, but throughout today, the model paths have slowly moved west. The Europeam ECMWF model has been the western most "trusted" model for most of the day and while the other "trusted" model GFS started out a bit east, it has moved over to meet the ECMWF model a bit, although the ECMWF has even drifted more westerly. It remains to be seen if this trend will continue or if we'll wake up tomorrow and see something else entirely on the map. For now, it's just a waiting game unless you live in the islands. Hopefully once Isaac has reorganized itself a bit into the type of storm the models know what to do with, and we have some of that nice data that NOAA went out and got today on their jet overflying the Bahamas, we'll maybe have a bit of a better idea where he's heading. But at the moment, he's drunk, surly, and just daring anyone to look at him funny.
Morning:
The models seem to have(for the most part) shifted east again. The NHC still is keeping pretty much to their forecast from yesterday though. Isaac still hasn't completely organized into something normal looking. It's still looking a bit lumpy on the satellite view, but it is looking better than it did yesterday. I still think the models are going to have some problems with it in it's current situation. It is currently heading west, and while it's against the forecast, it is possible we could see it head west even more. The ridge seems to be opening up which could allow Isaac to funnel through it but if it slips south of the ridge, it could continue west for a bit longer. It still seems a bit iffy where it will finally end up, but at the moment there are probably two options for the immediate future. It makes a, fairly soon-ish turn to the northwest, slipping into the Gulf across Cuba, or it continues west, south of Cuba, threatening Jamaica and possibly western Cuba.
Of these two, the former would probably be better overall. Eastern Cuba and Haiti both have large mountains which would help weaken Isaac. Also, there is a large, deep mass of warm water south of Cuba that Isaac could run into if it continues west. If it crosses Cuba sooner, it'll still run into warm water, but it will be much shallower and wouldn't provide as much potential for intensification.
In any case, Western Florida all the way to Louisiana, Cuba, Hispanola, and Jamaica should all be keeping an eye on this, nobody is safe yet despite what the forecast and models say. Models tend to be intensely unreliable outside of 3 days, and we're still a good 4-5 days from US landfall unless it manages an extreme east path and goes into the Florida Keys or South Florida.
Afternoon:
Isaac seems to be getting its act together and may have made a bit of a Northwest turn at this point. At the same time, however, it has also ingested some dry air from the west of it. Hurricanes run on heat and moisture, dry air dissipates both of these things and can be a severe hindrance to intensification. It should also, soon pass over Haiti and within 12 hours or so after that, Eastern Cuba. Both of these areas are very mountainous which can cause problems for it. None of these will likely be enough to break apart Isaac completely, but for now it's staggered and will probably have to wait until it's back over the open, warm waters of the gulf to continue intensifying. NHC reports the current maximum sustained wind speed at 60 MPH and several models suggest that it may not ever rise above this again. However, only time will tell.
The models should be able to get a better fix on things now that it looks like a better organized storm. ECMWF still suggests it will head towards the Louisiana-Mississippi border. GFS suggests a more eastern route, clipping the Florida Keys then curving into the Tallahassee area. Several models all collect between Pensacola and Tallahassee, Florida, so it's starting to look bad for the panhandle. We are still 4 days out from a panhandle landfall though, and Isaac has only JUST started it's Northwest turn. Anyone along the Western coast of Florida should be warned though, even without a direct landfall, you'll likely find strong winds and rain even from a close pass of Isaac. It's not currently very strong, but it is very big.
Half-hourly updated satellite loops of the Carribean and Gulf:
http://www.ssd.noaa.gov/goes/east/watl/loop-wv.htmlhttp://www.ssd.noaa.gov/goes/east/watl/loop-vis.htmlThe first shows water vapor in the atmosphere with the black and tan areas being dry air.
The second shows a basic visible picture of the cloud tops.
August 25th, 2012
11:15 AM EDT
Isaac seems to have been hit hard by Haiti, but Haiti has also taken a beating from Isaac as well. Flooding tends to be a real problem there and since there are still an estimated 300,000 people who are living in tents after the earthquake, there is serious danger. The Haitian Government and several NGOs are reported to have been trying to get people sheltered as best they can though.
From this point, Isaac seems tracked to clip part of Cuba and most models suggest it'll swing way west out into the gulf rather than hugging the coast. From there, it's anybody's guess whether it will swing back east or continue on a northwesterly track. The northern gulf coast seems to be the target but Eastern Louisiana and the entire western coast of Florida are still in the cone. It's likely that tropical storm force winds will extend very far from the center, up to 200 miles in the near future, possibly farther at it's next landfall. Intensity modelling is notoriously bad, much worse than the tracking and even that is not great. From here on out, we have a decent idea of where it's going, but how strong it will be when it gets there is an unanswered question. Nobody is expecting a 4 or 5, but I have heard the numbers 2 and 3 thrown around and it's likely to be at least a 1. Personally I think the NHC errs on the side of strength a bit too much, but it's better to have people prepared for something strong and not have it be as bad than it is for them to expect a slight breeze and get knocked over by a tree.
Evening: Still dramatic amount of uncertainty as to Isaac's final landfall location. His strength depends a lot upon how long he spends over open water. He got chewed up pretty well by Cuba today, but tomorrow seems to provide plenty of opportunity to reorganize and strengthen.
Pacific:
As I said, I don't look at the Pacific much, it's literally half a world away from me, but there is some interesting stuff going on over there at the moment. Typhoon Tembin is currently giving southern Taiwan a bit of a beating as a category 3 storm with winds sustained at 125 MPH and gusting to 155. If that wasn't bad enough, it looks as if the track might take it on a quick loop around for a second pass before moving Northeast up the Chinese coast . It looks as if they might be dealing with this storm hovering over them until Tuesday of next week. Taiwan is generally pretty well prepared and they get hit fairly often, but a forcast of 6 days worth of that sort of weather just hovering over or nearby you is never a good thing. Even if the winds aren't a problem, flooding might be from the sustained rain added to the storm surge.
Tembin has dramatically weakened since last night. It is currently a strong Category 1 storm but isn't expected to intensify much more than that. Rain is still a danger, but the winds should be manageable by most of Taiwan. It's still possible it could hang around Taiwan until Tuesday.
August 25th, 2012
Morning:
Tembin seems to be strengthening again slightly, but is still on track to loop and hit Taiwan again in the next couple of days.
One of the reasons of this odd looping path is possibly Typhoon Bolaven just east of Tembin. Bolaven is forecast to be even stronger but it will instead be heading north towards Korea or nearby China on Monday or Tuesday, first crossing the islands between Taiwan and Japan at some point on Sunday. These two storms being so close together has an effect on their steering as nearby storms tend to orbit around each other in what's known as the
Fujiwhara effect. As Bolaven is moving north, it'll probably pull Tembin along with it, dragging it back over Taiwan in that loop mentioned earlier.
Bolaven is approaching the islands between Taiwan and Japan as a very strong Category 4 storm. After passing there it is expected to encounter Korean shores as a Category 2 or 3 storm sometime Monday night or Tuesday morning.