Clark
Meteorologist
Reged: Wed
Posts: 1710
|
TD 12 Develops, Could TD 13 be far behind?
Tue Aug 23 2005 01:32 AM
|
|
|
(Note: this is an edited version of the intial blog posting from early this morning, adding updated information about newly-developed TD 12 and invest 97L.)
There's an old saying -- fool me once, shame on you, fool me twice, shame on me. After missing the signs with Bret early on in the season, Gert was fairly well-predicted. But, alas, the third time wasn't the charm, as an area of low pressure spun up over Mexico -- much like Gert -- Sunday night and, into Monday morning, reformed out over the extreme southern Bay of Campeche. Once over water, it rapidly organized into a tropical depression and tropical storm, much like Bret and Gert did earlier in the season, and is moving onshore at this time as a moderate tropical storm in central Mexico. While all three of these storms were just tropical storms at landfall, given recon data and their satellite appearances, there is no question that they each were bonafide tropical cyclones. Perhaps we'll see some research into what factors contributed to such development this season later on down the line -- it's truthfully a matter of miles as to whether any of these actually would develop -- but for now, Jose makes three.
If this continues and troughs begin to slide into the Gulf of Mexico, things could get interesting later this season, but that's mere speculation at this point. As for the future with Jose, it should rapidly weaken once it has moved entirely inland and dissipate sometime on Tuesday. Some of the mid-level energy may continue across central Mexico and emerge in the Eastern Pacific in a couple of days, where some of the dynamical models are trying to spin up a system down the line. We'll watch it for any signs of development there, but it most likely will not be Jose yet again.
Elsewhere in the basin, there are two features of interest: invest 97L out in the east-central Atlantic and newly-classified TD 12 near the Bahamas. As the latter is closer to shore, I'll tackle that one first. It's questionable as to whether this is the actual feature that was TD 10 a week ago in the central Atlantic, but the NHC and the other tropical agengies are going with a new system. Nevertheless, whatever is there has managed to persist for quite some time, despite minor interaction with land and now interaction with a mid- to upper-level low pressure system near 25N/71.5W. This is aiding in convective development to the SE of the low pressure area, where the winds are divergent aloft and an area of low pressure at the surface has developed. A building ridge to the north of the system should keep it moving west-northwest at a slow rate of speed over the next few days, primarily through the Bahama chain, but where it goes once it approaches Florida depends on the strength and extent of the upper-level ridge. Right now, there is probably enough of a weakness to stall the system or cause it to move further to the north; but, will this be there in 3-4 days? That's the key. Most of the statistical-dynamical models suggest that it should keep moving further towards the west, while the global dynamical models are split on its evolution. Given the favorable environment and projected steering flow, a burgeoning tropical storm as it heads towards the SE Florida coastline is looking like a possibility at this point, with a turn more towards the north -- somewhere between the west coast of Florida and New Orleans -- likely as it heads into the Gulf in a few days. Interests in Florida should keep an eye on this one -- at the least, enhanced rainfall (which for some areas is welcome and for others is not, all based off of the fluctuations of the sea breeze this summer) is a good bet as it approaches the state -- with a threat likely for the Gulf coast from New Orleans west in the next 5 days or so. Stay tuned to the blogs & the CFHC for more over the next few days on TD 12/Katrina.
Invest 97L has broken free of the ITCZ, something that bodes well for its development as well as for keeping it out to sea. A broad yet well-organized (per microwave imagery) area of low pressure (~1008-1010mb) was located near 17N/36W last night, but has since given indications of reforming closer to a mid-level center and underneath the organized convection at about 17N/35W. General motion is currently towards the west underneath an upper-level ridge. This is producing a favorable upper-level pattern for the system, but the subsidence aloft and dry air in the mid-levels is helping to keep development in check for the time being; the broad expanse of the system is keeping development to a slow pace. As noted above, convection is beginning to fire and sustain itself along the periphery of the area of low pressure, primarily in the eastern and southwestern parts of the system. As the center begins to become better defined underneath the convection --i.e. if current trends continue and the convection builds near to the center of the system -- it is possible to see a TD out of this one by the end of the day Tuesday or early on Wednesday. Given the expanse of the ridge, this one may continue west for awhile, but should ultimately be a fish spinner, probably near or east of Bermuda depending on how fast (if at all) it develops. Pretty good bet this brings us Lee in the next three days, I believe, given that developing TD 12 in the Bahamas has likely beaten it to the punch for the "K" name.
Model guidance -- specifically the long-range GFS -- keeps trying to develop more storms after these features, all the way through Labor Day. Given the gradually improving conditions in the eastern Atlantic and the wave train setting up over Africa, I feel that it is a good bet that at least one of the future waves will develop, with the potential for more. Always going to have to look for close-in development as well, particularly if yet another wave sneaks into the Bay of Campeche, but that will likely become a bigger threat later in September as Cape Verde season dies down in about a month.
In the East Pacific, Hilary didn't quite reach major hurricane status as forecast, but still prompted the issuance of tropical storm warnings for a portion of the SW Mexico coast on Sunday. It's heading out to sea now, likely to turn back towards the west as it begins to spin down over cooler waters in a couple of days, and behind it conditions appear rather benign in the basin (other than the feature noted at the outset) for the next few days. And finally, while it doesn't belong here so much, the West Pacific has an interesting case of two tropical cyclones with subtropical origins interacting with each other southeast of Japan. The first, Mawar, briefly reached super typhoon status over the weekend and is now headed for central Japan; the second, Guchol, was not quite captured by Mawar -- just a little too far apart and too much of an influence from the mid-latitude pattern -- and is headed out to sea. Nevertheless, an interesting occurence to watch.
It's getting active out there and with the threat to Florida & the SE US growing by the day, stay tuned for future updates from myself, Ed, Jason, HF, and the others here at flhurricane.com.
--------------------
Current Tropical Model Output Plots
(or view them on the main page for any active Atlantic storms!)
|
|
Previous
Index
Next
Flat
Edit
Reply
Quote
