Hurricane Earl takes direct aim at the Maritimes

Hurricane Earl is weakening as it runs into cooler water and feels the effect of the mid-latitude Westerlies. Intensity on the surface is about 75 knots (139 kmh/86 mph). The cyclone is tracking in a direction of north northeast at 18 knots (33 kmh/21 mph) as generally predicted by models and the NHC. Earl is expected to pass Cape Code as a hurricane and continue to weaken.

Earl will most likely make landfall as a strong tropical storm somewhere between the Maine/New Brunswick border and the southeast coast of Nova Scotia sometime on Saturday morning.

The Canadian Hurricane Centre has issued Tropical Storm Warnings for most areas of mainland Nova Scotia and all of Prince Edward Island. Hurricane watches are in effect for Halifax, Lunenburg, Queens, Shelburne, Yarmouth and Digby counties of Nova Scotia.

Tropical Storm Watches are in effect for the remainder of Mainland Nova Scotia, Cape Breton Island, Southeast New Brunswick and Iles de la Madeleine.

Two items are worthy of mention. The winds on the east side of Earl will be markedly greater than the western semi-circle due to its direction of advance. Depending on the time Earl arrives and the direction of its approach to land, the storm surge in the Bay of Fundy could be significant and dangerous, however, expected time of landfall (at low tide) and the Neap tide cycle may mitigate the danger.

TS Fiona is still active and has survived despite considerable wind shear. Tracking north northeast at about 11 knots (20 kmh/13 mph) with weakening wind speeds of an estimated 40 knots (74 kmh/46 mph), Fiona is about 18 hours away from making a direct pass over Bermuda.


Busy weekend for some.

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.

Hurricane Earl and Tropical Storm Fiona - 312230Z

The above video provides a graphic image of the size and power of Hurricane Earl. It comes in toward the end of the clip. About half way through you can see the edge of Hurricane Danielle making a recurve out toward the North Atlantic.

Earl is undergoing an eyewall replacement cycle which has a tendency to reduce the intensity somewhat. The cyclone is getting some significant wind shear although it is powerful enough that it may not be weakened as a result. All of the models show a weakening of the wind shear generating upper low as Earl moves by.

As forecast, Earl has begun to recurve to the northwest. It is currently tracking about 305 degrees true, advancing at roughly 12 knots. Wind speeds at the surface are estimated at 115 knots (213 kmh/132 mph). Hurricane watches have been issued for the US east coast from north of Surf City, North Carolina to the NC/Virginia border. Tropical Storm warnings have been issued for the Turks and Caicos Islands.


TS Fiona tracking just north of west at a phenomenal 21 knots (39 kmh/24 mph) is expected to start experiencing some fairly significant wind shear which will probably prevent it intensifying beyond a tropical storm. This cyclone is expected to turn northward and decelerate in the very near term. The influence of Earl will likely cause Fiona to dissipate sometime in the next 36 to 48 hours.



Below is a shot from the GOES13 project which captured the North Atlantic at a busy moment. To the north is Hurricane Danielle, Hurricane Earl to the south and further to the east is the rapidly approaching TS Fiona.


Click on any image to enlarge.

Hurricane Earl and Tropical Storm Fiona - 310001Z

Hurricane Earl intensified this afternoon and became a category 4 cyclone. In short, this system is big and powerful. It is tracking through minimal wind shear and very warm sea surface temperatures which will likely see it intensify even further over the next 48 hours. It is still tracking slightly north of west at about 13 knots (24 kmh/15 mph).


While the storm is still expected to recurve northward, its continued forward speed to the west has shifted the forecast track somewhat west. This brings the forecast even closer to the US eastern seaboard and should give Nova Scotia some moment of pause. While it is still far too early to forecast a landfall, most models have this cyclone reaching as far west as Maine or as far east as seaward of Nova Scotia as a possible category 2 hurricane.


Invest 97L was upgraded to a tropical storm and is now TS Fiona with rain bands starting to appear in wind fields of about 35 knots. Whether Fiona intensifies or not is difficult to say. It is tracking almost due west at 21 knots (39 kmh/24 mph) which means it is moving closer to Earl.



I know the immediate response to this is to expect that the two cyclones will merge to form an even bigger storm, however, that's not what happens. Earl is generating strong upper outflow winds which will create strong wind shear in Fiona's path. With that happening, and with Earl robbing Fiona of moist air, there is a fairly decent chance that Fiona will lose its energy and dissipate. If... it keeps moving at its current speed. If it slows down Fiona could become a whole different story.