Statement as of 5:00 am EDT on August 27, 2006
big changes in both the initial intensity and forecast track were required...unfortunately...for this advisory. Latest recon data indicate Ernesto is likely undergoing rapid intensification. An eye is forming and maximum 850 mb flight-level winds of 78 kt were recently observed in the northeast quadrant...which equals about 62 kt surface winds...so Ernesto is very near hurricane strength. The eye is so small...however...that the flight crew have been unable to properly assess the minimum surface pressure. The satellite appearance has become quite impressive with little or no vertical shear noted on the system now...and cirrus outflow expanding outward in all quadrants.
The initial motion estimate is an uncertain 295/08...based on a 12-hour average motion. The center has been reforming closer to the strong convective bursts with cloud tops as cold as -85c. It is possible that additional reformation of the low-level center closer to the center of the round convective cloud mass could bring Ernesto over or very close to the southwestern tip of Haiti later today. For that reason...a Hurricane Warning has been issued for southwestern Haiti. Now for the rest of the bad news...the official forecast track has been shifted significantly to the right or east of the previous track...especially at 96 and 120 hours..and now takes Ernesto across the Florida Peninsula. The consensus of the available model guidance now indicates that a strong shortwave trough currently over the central and southern rockies will dig east-southeastward into the western and central Gulf of Mexico... causing the subtropical ridge situated over Florida and the southeastern U.S. To gradually erode eastward. The GFS and NOGAPS models appear to be eroding the ridge to quickly and have Ernesto over southeastern Florida in 84 hours. The rest of the model guidance takes the cyclone farther westward over or west of the lower Florida Keys. However...all of the global and regional models now agree on recurvature over the eastern Gulf of Mexico around 96 hours...and take Ernesto northeastward across the central or northern Florida Peninsula by 120 hours. The official track is similar to but a little west of the consensus models. The intensity forecast was as equally difficult to prepare as the track forecast was...and it highly dependent on the exact track that Ernesto takes due to land interaction with Haiti and Cuba. Excluding land interaction...the environmental and ocean conditions current and forecast to be affecting Ernesto are highly conducive for rapid intensification in the near term...and for the potential development of a major hurricane in the longer term. Water vapor imagery and 00z upper-air data indicate the vertical shear is rapidly decreasing while the outflow is rapidly expanding. In fact ...Outflow channels have now developed to the north and south of Ernesto...with a third channel possibly developing to the west and into an upper-low moving rapidly westward toward the Yucatan. This very favorable low-shear and enhanced outflow pattern is forecast by all of the global models to persist right up until landfall along the Florida West Coast. If Ernesto doesn't linger over Cuba for more than 24 hours...then major hurricane strength seems likely by 96-108 hours. The official intensity forecast is similar to but higher than the SHIPS...GFDL...and FSU superensemble intensity model forecasts.
Forecast positions and Max winds
initial 27/0900z 17.0n 73.1w 60 kt
12hr VT 27/1800z 17.8n 74.5w 70 kt
24hr VT 28/0600z 19.3n 76.3w 85 kt
36hr VT 28/1800z 20.6n 78.1w 85 kt
48hr VT 29/0600z 22.1n 80.2w 70 kt...inland
72hr VT 30/0600z 24.4n 83.1w 80 kt
96hr VT 31/0600z 26.5n 84.0w 100 kt
120hr VT 01/0600z 30.0n 81.5w 70 kt...inland
$$
forecaster Stewart
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Resume dirtboy comments: Everyone in South Florida needs to pay VERY close attention to this storm now, because it's only about three days out according to current forecasts. There is a good chance it might shift away or get chewed up over eastern Cuba, but you cannot count on that happening. IMO it is time to start thinking about what you're gonna do if this storm blows up and tracks as forecast.
It looks like the Tampa Bay area is in the storm's sights. I don't think they have had a major storm in a long time. Of course a lot can change over a few days.