United States

Update on Leslie

September 06, 2012; 5:22 PM

Hurricane Leslie continues to drift slowly north-northwest to north under a very weak steering environment. Latest observations and model trends indicate that Leslie will end up tracking east of Bermuda sometime Saturday night which is good news for the islands of Bermuda. This track keeps the strongest winds away from the islands.

This farther east location will also have implications farther north into Atlantic Canada.

With the center of Leslie not getting any farther west than 64 degrees longitude between 30 and 35 north latitude it gives us high confidence that the center will indeed pass well east of Halifax, NS, early next week, reducing the threat for a damaging storm greatly over western NS, PEI and New Brunswick.

The latest trends are also better news for Cape Breton, but I would not be celebrating just yet. We still have a few more days to watch this thing.

Update: new ECMWF model has center landfall over south-central Newfoundland Tuesday night.

Yesterday, I was leaning toward a center landfall (strong tropical storm or Category 1 hurricane) over Cape Breton Island, NS. I have not ruled that out, but I will say that the latest set of computer modeling has trended even farther east and averaging a center landfall over southern Newfoundland early Tuesday.

There are a couple reasons for this eastern shift in the forecast tracks.......

1. Initial location and track of Leslie today. It seems that Leslie has very little westward component left in it based on recon.

2. The upper high currently north of Leslie is a little weaker than the modeling had yesterday. This reduced the initial westward component of movement.

3. The strong trough (dip in the jet stream) coming into the Great Lakes and eventually eastern Canada this weekend is moving a little quicker and the energy does not look like it will dig southward around the trof, which would tend to pull Leslie more north instead of north-northeast Monday. Instead, it looks like the energy just lifts northeast around the trough allowing the trough to move more quickly east and in turn allow Leslie to turn more northeast toward Newfoundland and not the Maritimes.

I currently like our track taking the center of Leslie into south-central Newfoundland early Tuesday. We currently have it as a Category 1 hurricane at landfall, but this far north it will already begin the slow transformation toward an extratropical storm, which allows the strongest winds to spread out away from the center.

This track would clearly bring the worst conditions (blinding rain/damaging winds) into the Avalon Peninsula of Newfoundland Tuesday with 30+ foot seas just offshore.

In the meantime, get ready for some fall-like weather during the Saturday-Monday period in eastern Canada. Nice break for the humidity.

-------------

Snow in the mountains early next week.......

By the way, a significant cold front will push into western Canada by early next and we may see some snow (not a lot) in the Canadian Rockies down to 5,000 feet. Best chance for accumulation will be west of the divide.

The views expressed are those of the author and not necessarily those of AccuWeather, Inc. or AccuWeather.com