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It's true that some of the models keep hinting at an "end of cycle" development near or around Yucatan. Could happen but so far such little model consistancy. MJO "is" coming around and seemingly influential in Carlotta's development. In fact I am kind of surmising that those lower pressures that you noticed at the 850mb level are ( or will be ) the extention of the broad mid to low level circulation of Carlotta after (1st??) landfall on the Mexican coast in a few days. Seems to me that heights will remain low down in the Southwestern and Western Caribbean. Couple this with what the Euro appears to show as a weak wave at about 180-216 hour migrating westward across the south central Caribbean and who knows? Unspecific to the near term, I am a little taken aback at how conditions across the Atlantic have evolved over the recent couple of weeks. It is of course to be expected over time that SST's would warm, that the 200mb westerly shear should weaken, and subtle changes to overall steering flow would occur. Models would seem to indicate a significant long wave shift with the trough appearing to be setting up near the central plains. In perhaps 126 hours, the outright westerlies seem to quickly transform into a East Coast TUTT with a couple shear zones traversing across the Caribbean, yet only to quickly evolve further with evidence of significant ridging in the E. Atlantic. Even after the long range appears to drop a deep trough down the E. U.S. Seaboard, stronger ridging pushing in from the deep tropics looks to quickly bridge across the Antilles to a building ridge over the Southeast. Looks to me like a significant amount of relative short term transitional changes will be occuring in the upper atmosphere. For the mid levels, even more interesting to me would be the changes that the GFS are indicating at the 500mb level. Regardless whether talking about the W. Caribbean or mid-Atlantic, recent steering at even the lower latitudes have been practically southerly or southwesterly. For the Easterlies to slowly transition would be typical. However for the first time this season, 72hr. GFS depicts a solid 594 ridge building westward in the E. Atlantic. Over time, not only does ridging establish itself across the Atlantic and Caribbean, but would appear to me that significant ridging will establish itself around 60W and further south than last year. Around 300 hour, solid ridging would appear to have extended from Africa westward all the way to the southern Plains. These long term forcast maps cannot be used for reliable day to day guidance, but assuming general consistantcy, can be usefull to anticipate overall large scale pattern evolution. Then...., we have sea surface temps! Looking at NOAA/NCEP maps, it seems to me that a good deal of "Atlantic real estate" appears to be a good deal warmer than 1-2 weeks ago. No doubt nearly all the Caribbean and Gulf are at 28C, but to be sure I wanted to check out the most recent anomolies. It would appear that a good deal of the Central/Western Atlantic is a degree warmer than normal with the W. Gulf up to 2 degrees warmer. Colder than normal water exists off the African coast and much warmer than normal SST's oddly exist in the far North Atlantic and Canadian maritimes. Finally, you throw in the anticipated impacts of a late summer El Nino and "now" try to look ahead into the crystal ball and attempt to figure it all out. What does it all mean? I'm rather stumped. I typically feel a strong "sense" of how the season will play out; maybe a WRONG (LOL) sense, but a feeling nonetheless. My only sense of the season that I am sticking too, is with regard to areas of formation and general motion. I still think there will be few long tracks and area's of origin to occur in the Gulf, Caribbean, and perhaps within 10 degree's east of the Caribbean. Perhaps a good bit more activity impacting land than in recent years. I don't think El Nino will have a significant impact to the Atlantic season outside of perhaps supressing a bit of the season's late Oct./Nov. systems from forming. |