Could be a wobble, an error, any of dozens of kinds of anomaly.
That’s why I post the disclaimer. I never post a landfall prediction more than 24 hours before the ETA. I start posting landfall PROJECTIONS as soon as possible after I become aware of a storm and can clear the decks of other activity long enough to download the positions and plot them. Huge difference between a prediction and a projection.
A projection says “this is where it’s pointed right now”, and cannot be argued with on any rational basis.
A prediction says “this is where I think it’s going to go next”. I’ve seen way too many hurricanes to ever make predictions more than 24 hours out, and even then, I usually hedge my bets.
There’s no telling what Dean will do before it’s all said and done.
However, projections based on what Dean has done so far are useful for two reasons.
One, it gives us a timeframe to begin with. Odds of a US strike before midweek next week are very low, based on current behavior. That allows me to get things done early next week, freeing up the late week and weekend for full attention to Dean, if Dean hasn’t changed course or speed by then.
Two, it gives us a baseline to plot changes against. You can’t have a wobble with only one position plot. No wobble with two position plots. No wobble with three position plots. You have to have four position plots to note a wobble. You really need five before you can start putting any confidence in a wobble.
You have to have at least three position plots to posit a course change. Four to place any reliability on a course change.
You have to have at least two data points to say it is strengthening or weakening.
Even though we know that Dean is liable to do anything between now and the time it dies in the North Atlantic (Pacific?), we have to start plotting data somewhere, to build a trend to measure future changes against.
If I lived anywhere in the Gulf of Mexico, I’d be making sure I had wood screws, canned food, batteries, battery driven comms, lights that don’t need a grid to work, and bottled water onhand right now. (I’m a thousand miles from the Gulf, I always have this and mich more preparations ready at all times, and in my opinion, starting preps for hurricane season right now is several months late, but if someone hasn’t, now’s a better time to start than Wednesday, when the store shelves around ground zero will be barem and the evac freeways already clogged.)
If I lived between Brownsville and Corpus Christi, Texas, I’d be making sure my plywood was in good shape, and un-burying the plywood stockpile and my ladder, and charging the batteries for my cordless drill.
It’s too early to commit, but it’s not too early to lean forward, especially for Brownsville and points north, all the way over to Mississippi.