ECMWF Scorecard – 1 Hit / 1 Miss / 1 Uncertain

Last week, we discussed how the tropics were coming alive with the formation of Gustav and Hanna along with several other strong disturbances coming off the west coast of Africa. Since then, we’ve seen the formation of major Hurricane Ike in the central Atlantic and Tropical Storm Josephine west of the Cape Verde Islands. As far as where these storms would go, my focus last week was on the European model (ECMWF), one of a few models that goes out to 10 days in the future. (The other model that goes out to 10 days or more being the American model (GFS) which didn’t really show Gustav or Hanna well as of last Friday.) A week has passed, so let’s see how the European model did with last Thursday’s predictions. First we’ll look at Gustav.

Last Thursday morning’s run of the ECMWF predicted that Gustav would cross the western tip of Cuba on Sunday morning and make landfall along the mid- Louisiana coast in Terrebonne Parish on Tuesday morning, as indicated by the map below valid Tuesday, September 2^nd at 7AM CDT:

I’d say that the European did very well with its 5-day forecast of Gustav. On the map above, note that the ECMWF has Hanna near the eastern Bahamas last Tuesday. That’s not far from where Hanna was on September 2^nd. From that point, Hanna drifted southward to just north of Haiti on Wednesday, then turned north and is currently heading for a landfall along the North Carolina coast tonight (Friday, September 5^th). Let’s see where the ECMWF model predicted that Hanna would make landfall:

Wrong! The ECMWF had predicted that Hanna would make landfall in southeast Louisiana tomorrow, September 6^th, not far from where Gustav struck the coast. That’s definitely a bust. So the European is 1 for 2 in the landfall predictions. Note where Ike is on the map above, trailing Hanna by 4-5 days. In fact, that’s not too far from where Ike will be tomorrow morning at least as far as its longitude is concerned. But the ECMWF has Ike up near 25N latitude and it’s actually going to be closer to 22N latitude by Saturday morning. About 200 miles too far north for the prediction of Ike from 7 days out. Not bad, really. But where was the ECMWF predicting that Ike would be in 10 days? The map below is the 10-day ECMWF forecast from last Thursday, August 28^th valid for Sunday morning, September 7^th.

On the map above, Ike is forecast to be well to the east-northeast of the Bahamas on Sunday. The current forecast is for Ike to be over the eastern Bahamas on Sunday morning. So the ECMWF is about 800 miles off – too slow and too far north. Now you may be asking, where is the current ECMWF forecasting Ike to make final landfall? I’m glad you asked.

For the past several days, the ECMWF has been forecasting Ike to take a track directly toward Miami, come to a dead stop, then turn north and head toward eastern North Carolina. But as you can see below, the most recent run of the ECMWF (7PM CDT Thursday, Sept. 4^th) takes Ike inland into the central Louisiana coast next Friday afternoon, September 12^th:

That’s quite a switch. Though the ECMWF is the only model indicating a landfall in Louisiana, other tropical models continue shifting Ike’s northwesterly turn later and later with each run. The latest model runs as of 7am CDT this morning take Ike near the southern tip of Florida on Thursday morning then northward over or just west of the western Florida Peninsula Tuesday afternoon and Wednesday, then inland into the eastern Florida Panhandle on Thursday of next week.

We’re not really sure just when Ike is going to make the northwest and northward turn early next week. Though the threat does look to be shifting farther west, Ike could still make final landfall anywhere from the Carolinas to the western Florida Panhandle. And then there’s that European model that seems to have an affinity for Louisiana landfalls.

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