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there's a 'too weak' out on 90L from ssd. i concur... not very well organized at all. there are a few issues that should keep the development slow as is typical with these late-season caribbean features, and of course there is the chance that it can't manage to develop at all. on the west side of the system the northerly flow in the wake of wilma has plunged all the way down to the western side of panama. there's a sharp convergence line, with the tropical easterlies asserting themselves and pushing the line a little west.. all the while the weak contra-flow often on the pacific side of panama is curled up over the eastern side of the country. end result is a broad gyre at low latitude. it would definitely fester if the upper environment was good and it were focused a little further north, but there is the issue of some nw shear that has swept around underneath the large upper ridge that wilma left, making an elongated cyclonic turning across much of the caribbean. the intrusion of this semi-hostile upper air flow should keep the surface system from focusing easily. as models forecast the disturbed weather to persist for days, it may win out in the long run... but don't expect a classifiable system tomorrow and probably not on thursday either. system further east really has the same type of prospects. it is taking a trajectory and progged path similar to the one alpha took days back. not quite as organized at this point, and not under quite the same upper environment.. but as the cyclonic flow over the caribbean contracts there is some ridging/diffluence aloft trying to establish near the wave. its signature has increased slowly through tuesday, and most models track this feature though none are very aggressive with it. i'd say in the long run it has similar chances to what alpha had. like the 90L invest it won't organize very quickly. thought i'd pick up on the rant from earlier about the saffir simpson scale. putting a category 6 on would be kind of stupid. there would be so few category sixes as to make pointless the classification... case and point there are so few fives. since we had a banner crop this year it seems like they're more plentiful, and we had isabel and ivan during the previous two years. prior to that there were two in the 1990s, three in the 1980s, and three in the 1970s. pretty doggone rare. there are seldom few examples of pressure below 900mb, which is where the next logical cutoff would be. we somehow managed two this year, and almost 3. re-doing the saffir simpson scale would be sort of pointless also. it describes the effects you can expect with a particular intensity range... not matched too generically. the forecasts issued by the hurricane center and locally calibrated give a pretty good assessment of what to expect from a storm. storms are going to be rated by their most intense characteristics... thus you'll always get storms like charley and andrew more intense than wilma and ivan were at landfall... though the latter had potential for much more widespread wind damage. katrina illustrated very well how surge doesn't necessarily match up with the saffir simpson expectations. it hit at a 4, secondary on ms at a 3.. and the surge was well above what camille or the labor day storm managed. a more useful thing to do would be to split the categories by effect.. i.e. katrina in ms had cat 3 winds but a cat 4 pressure and cat 5 surge. adjust accordingly. yes, you can weather the cat 3 storm winds in your home if it's well constructed. no, if you're not more than 25' above sea level you're screwed. the idea of using rainfall is a little spurious. case and point tropical storm allison and alberto in 1994. stan is giving katrina a run for deadliest storm this year, and it was nowhere near as strong. something else they could probably do better with is inland wind decay. hurricane force winds really don't make it far inland unless a hurricane is booking. the hurricane center really only does coastal areas. local weather service offices don't always come up with congruent ideas on how the inland wind impacts will come, and often they overdo them. wish the nhc would put out inland wind decay forecasts. 'nother thing i kinda wish the hurricane center would consider is lengthening the watch/warning times. they've taken the plunge and shown good skill with 4-5 day tracks in many cases. the old criteria of 36hr warning and 48hr watch sort of sells their forecast ability short. there should be a longer term alert they can put out, i.e. something from 72hr to tell people 'get you stuff together, get vulnerable things secured and persons ready to go'. probably economics keeping them from doing that, and the risk of making people complacent with storm alerts.. but i tell ya, after new orleans... the benefit may outweigh the risk in the long-run. that's a hell of a lot. guess i'll just shut up before i write a book. y'all take it easy. HF 0524z26october |