Hurricane Watch for Nova Scotia

As Hurricane Earl advances the Canadian Hurricane Centre has issued a Hurricane Watch for Yarmouth, Queens, Shelburne and Digby Counties in Nova Scotia. The remainder of the province with the exception of Cape Breton Island, is under a Tropical Storm Watch. In New Brunswick, a Tropical Storm Watch has been issued for Gand Manan and Coastal Charlotte County, Saint John and County, and Moncton and Southeast New Brunswick.

Earl has weakened slightly and is now proceeding due north at about 16 knots. The conditions of warm, humid air and high sea surface temperatures suggest Earl will make a Canadian landfall as a hurricane with tropical characteristics and not become an extra-tropical storm until after it passes into the Gulf of St. Lawrence.

The probabilities of Earl reaching Canadian locations as a Cat 1 hurricane in the next 48 hours, as provided by the NHC are as follows:

Yarmouth NS - 43%
Halifax NS - 16%
St John NB - 27%
Moncton NB - 21%

TS Fiona is tracking as previously discussed and is unusually persistent, having survived despite the higher wind shears.

Gaston has died and is now declared a remnant. That doesn't mean it can't regenerate later, but for now it no longer presents a threat.

A new tropical wave is being closely watched off the coast of Africa.

More later.

Hurricane Earl, Tropical Storm Fiona and Tropical Depression Gaston - 021400Z

Hurricane Earl, an intense category 4 cyclone, is now about 300 miles south of Cape Hatteras. The storm is moving north at about 16 knots (30 kmh/18 mph). It is packing sustained winds of 125 knots (232 kmh/144 mph). The centre of Earl is expected to be abeam the North Carolina Outer Banks by tonight. Sometime in the next 8 hours Earl should peak in intensity. The ocean buoy at Diamond Shoals is showing a significant increase in wave height, dropping sea level pressure and increasing ENE winds.

The NHC has issued Hurricane Warnings for North Carolina from Bogue Inlet northeastward to the NC/Virginia border with Hurricane Watch and Tropical Storm Warnings or watches along a majority of the US east coast. (Click the link for details).

The Canadian Hurricane Centre has issued a Tropical Storm Watch for Yarmouth, Shelburne and Queens Counties in Nova Scotia. (Port Maitland to Medway Harbour)

Earl is now moving around the western edge of the subtropical ridge and will encounter the base of the Westerlies in about 24 hours. An upper trough moving out of the Great Lakes will interact with this cyclone causing it to accelerate its speed of advance as it begins to track more toward the northeast.

For the Canadian Maritimes the problem is high air temperatures over the region and sea surface temperatures that are as much as 4 degrees Celsius higher than normal. There is a possibility that Earl will retain its tropical features as it approaches the Nova Scotia coast. Earl will likely arrive at the Canadian Maritime coast early Saturday morning, somewhere between the New Brunswick Fundy shore and the South Shore of Nova Scotia.

TS Fiona is tracking north-northwest at 15 knots. This storm is challenged by a lot of northerly wind shear. While it still has sustained wind speeds of 45 knots (83 kmh/52 mph) it is expected to weaken in the next 36 hours and dissipate by late Sunday.

A Tropical Storm Warning is in effect for Bermuda as Fiona's current track takes the cyclone directly through that island late Friday or early Saturday morning.

Tropical Depression Gaston is one to watch after Earl passes. It was downgraded as a result of the lower intensity winds estimated in its centre. However, it is in a position where conditions will exist to allow strengthening in the next 96 hours although that will be fairly slow. Gaston is moving slowly towards the west at about 6 knots (11 kmh/7 mph). This slow advance will give Gaston time to develop once the upper air conditions change.

Hurricane Earl, Tropical Storm Fiona and Tropical Storm Gaston - 012100Z

Hurricane Earl is tracking towards the northwest at about 15 knots. At present the outer edges of the wind field are just east of Abaco in the Bahamas. Maximum sustained winds are about 115 knots (213 kmh/132 mph). Hurricane warnings have been issued for the North Carolina coast. Conditions suggest that Earl will restrengthen to category 4, possibly by later today. The coastal area under a Hurricane Warning can expect a destructive storm surge in the range of 3 to 5 feet above ground level. The swells being generated ahead of Earl have already started to reach the Bahamas as can be seen on this Abaco webcam. Large swells will begin to hit the US east coast shortly.

As Earl reaches the edge of the subtropical ridge it should start recurving more to the north-northwest and then north, possibly as early as tonight. As Earl encounters the Westerlies it should start to turn out towards the east by Friday morning. All the models seem to support this and the NHC is issuing that guidance. Earl should weaken in intensity but increase the speed of its advance as it encounters greater wind shear. If there's a problem it is the record warm waters it will encounter as it leaves the tropics. The Gulf Stream is certainly warmer than it has ever been and it is providing enough sea surface temperature to support a hurricane.

Models produce a small westward adjustment of Earl's track. That continues to suggest that Earl will make landfall somewhere between Maine and the South Shore of Nova Scotia, most likely with Tropical Storm force. (This could create a massive surge in the Bay of Fundy.)

TS Fiona is a small Tropical Storm with sustained winds of 50 knots (93 kmh/58 mph). The cyclone is showing tropical storm force winds with a radius of only 100 miles around it.

Fiona is tracking towards the northwest at about 17 knots. That's still pretty fast and most models suggest that Fiona will continue in that direction but begin to slow significantly. Intensity at this point is a touch call, however, the cyclone should be influenced by Earl in the next two days which should put the cyclone into the decay stage.

TS Gaston is in the centre of the tropical Atlantic moving slightly north of westward at 13 knots. Initial intensity is sustained winds of 35 knots (65 kmh/40 mph). Gaston will encounter a couple of conditions which will challenge development: There is a considerable amount of dry air to the west and north of it; and, the weakening subtropical ridge will cause it to slow. Most models show Gaston becoming a hurricane within the next 5 days.


As always, click any image to enlarge.

Added: A look at the Atlantic this evening with the named storms identified.