The section I wrote below was issued via the email distribution list this afternoon. Granted my ideas on windspeed intensity may not pan out as I think it is doubtful this storm will ever regain hurricane status again. But in the same breath I think back to Ivan in 2004, and how the models were trying to tell us something about the eventual track, but no one could figure it out until we noticed the circulation center had actually maintained it's structure, crossed back over Florida, reemerged in the Gulf and almost made it back to hurricane strength believe it or not before hitting Texas as a medium-range tropical storm. I wonder if the East Coast stall scenario playing out on the maps is an indication that this will turn into a massive rainmaker.
Written at 3:30 PM 8/28
UPDATED ANALYSIS OF ERNESTO’S FUTURE TRACK, LANDFALL AND INTENSITY
Ever-changing Ernesto has been confounding forecasters, including me, since the first 5 day projection was issued. It’s a good thing we all have instant access to technology and have been able to monitor the movement of this storm. It seems that each time a forecast was issued, the storm was already in the process of undoing that forecast. Obviously my predictions issued on Saturday have proven to be way off, but at least it is a relief to storm weary residents of the Gulf that what I projected did not come true.
My main concern for the future of this storm is the computer models continue to have a difficult time initializing the storm, mainly because the center of circulation keeps reforming in different places. Since the major models commence a data run every 6 hours, the storm has changed so much that by the time an updated forecast track is ready to be issued, the information already seems inaccurate. This is not a knock on forecasters, mind you, it is just one of the many reminders that even the most powerful computers in the world may never be able to uncover the nuances and inner complexities of tropical systems.
That leads me to the big issue…which is almost like a repeat of the winter storm rule: “Predict the High and you predict the storm.” I can’t take credit for the rule, it was created by a Penn State meteorology professor, but I have applied it to my storm analysis and sometimes it works out. That’s where I’m going to hang my hat with Ernesto. Here’s a scenario I see happening based on the uncertainty we’ve experienced thus far..based on a trend first picked up by the European models which is shown below (valid for 7AM Saturday)
Several models show a large Canadian high moving off the New England coast by end of the week..but not so much that the high provides an easy escape for Ernesto as with Floyd in 99. The problem is that this could become a defacto “blocking high” because it may not move off fast enough. The storm appears to be heading out to sea or at least raking the coast with tropical storm to hurricane force winds for days on end. When it begins to turn northeast, it appears the Mid-Atlantic is spared (when in actuality a nice soaking rain would be just right about now). Instead of racing off to the northeast, the storm slows and gathering strength over the Gulf stream near the Carolinas. Then, as the high slowly fades east, a trough develops along the Mid-Atlantic, the pressure gradient tightens as the storm approaches, and placement of the high sends a large, slowly eroding hurricane back over the NC-MD I-95 corridor similar to Isabels’s path, only just a bit farther north. Hurricane watches and warnings are quickly raised, but the public is given less than 24 hours notice due to the rapid change in the forecast. The end result is a slow-moving, 75 mph hurricane moving along the DelMarVa or even in the southern bay..stuck between two highs..one in the North Atlantic and the other in southeast Canada. (10 PM update: doubtful we'll see winds of that strength now, but we could see the equivalent in rain..5-10")
Post below was written at 5:30 AM 8/28
- Frictional effects can be a double-edged sword.. because once over Cuba, the opposite effect could take place in that once the northern 1/3 to 1/2 of the storm (not the center) crosses over land, the SE quadrant offshore winds will be the last to weaken, and the those winds funneling energy into the storm counter-clockwise could serve as a opposing force. What I mean by this is while I agree Ernesto will be fouled up by the highly mountainous terrain of eastern Cuba, I also think it is possible the storm will not linger over the island as long as is currently being projected. There are some theories (or perhaps it is a verifiable phenomenon of tropical systems) that storm centers can “sense” a source region of warm water and have a tendency to be drawn to the source if it is in close proximity to the center.
Since today is the first official day of school in Baltimore County and elsewhere I cannot post to the site during the day, but will issue an update via the distribution list this afternoon followed by a website update this evening,