6:15 AM EDT Update Thursday, 2 September 2010

Hurricane Earl has probably peaked earlier this morning, but remains a strong category 4 storm. It is forecast to come very close (40-60 miles) of the outer banks, still as a major hurricane. Any deviation to the west would bring the worst of it onshore. Those in the warning areas should pay attention to local media and officials about any evacuations or recommendations.

Today should be spent in final preparations and leaving as conditions will begin to deteriorate in North Carolina in the late afternoon or evening. Closest approach to North Carolina would likely bit in pre-dawn hours tomorrow.

After passing near/over North Carolina, Earl is forecast to stay offshore the mid Atlantic, but Nantucket has a chance to get part of the western eyewall. Because of this hurricane watches are in effect now (in addition to the other warnings/watches) from north of the NC/VA Border to Cape Henlopen in Delaware. And now also from westport to Plymouth, MA (along with cape code/Martha's Vineyard and Nantucket) Those in Martha's Vineyard and Nantucket would be wise to begin preparations now.



Wind fields tend to expand when the storms get further north, so there is a good chance a large area in the northeast may experience some strong winds.

Beyond that, Extreme Northeast Maine may be a landfall, and Canada will either way, and it is likely Earl still will be a hurricane when it does.

Fiona is on the out to sea path, but has a chance to come close to Bermuda (on the west side). Therefore Bermuda is under a Tropical Storm watch for FIona.

Gaston is remaining weak this morning, but expected to continue to track west. Gaston is moving much slower than the other storms, and may not reach closer to the Leeward islands until mid-late next week. Odds favor Gaston not going out to sea, so it will be one to watch then.

Beyond Gaston is another wave (not being tracked as a proper invest yet) that has a 10% chance to develop over the next 48 hours, but more of one later on.

Mid-Atlantic/Carolina Links Southeast Composite Radar Loop (Latest Static)

Wilmington, NC Radar Long Range Radar Loop ( Latest Static)

Morehead City, NC Radar Long Range Radar Loop ( Latest Static)

Norfolk/Wakefield, VA Radar Long Range Radar Loop ( Latest Static)

Area Forecast Discussions: Wilmington, NC - Morehead City, NC - Norfolk/Virginia Beach/Hampton Roads, VA
Southeast Composite Radar Loop (Latest Static)
Northeast Composite Radar Loop (Latest Static)
Northeast US Radar Links Northeast Composite Radar Loop (Latest Static)

Dover, DE Radar Long Range Radar Loop ( Latest Static)

Mt. Holly, NJ Radar Long Range Radar Loop ( Latest Static)

Upton/NYC/Long Island, NY Radar Long Range Radar Loop ( Latest Static)

Boston/Cape Cod, MA Radar Long Range Radar Loop ( Latest Static)

Portland, ME Radar Long Range Radar Loop ( Latest Static)

Carabou, ME Radar Long Range Radar Loop ( Latest Static)
Flhurricane Recording of Radar (and more) of Earl US Approach
Keep up with where Mark Sudduth (Hurricanetrack.com) is as he drives around the Outer Banks of North Carolina

Media:
WECT 6TV - Wilmington, NC
WITN 7 - Eastern North Carolina TV (NBC)
WCTI 12 - Eastern North Carolina (ABC)
WNCT TV 9 - Eastern North Carolina (CBS)
Wavy 10 (NBC) - Hampton Roads/VA Beach, VA TV
WTKR 3 (CBS) - Hampton Roads/VA Beach, VA
WVEC 13 (ABC) - Hampton Roads/VA Beach, VA


Papers:
Outer Banks Sentinel
Wilmington Star News Online
Hampton Roads Pilot

Keep up with where Mark Sudduth (Hurricanetrack.com) is as he drives around the Outer Banks of North Carolina

Canadian Hurricane Centre

Flhurricane Recording of French Antilles radar for FIona Approach
StormCarib Reports from the Caribbean Islands

Caribbean Weather Observations

Caribbean Broadcast Corporation (TV/Radio from Antilles)

San Juan, PR Radar Long Range Radar Loop ( Latest Static)


Earl Event Related Links

Animated Skeetobite Model Plot of Earl
SFWMD Model Plot (Animated Model Plot) SFWMD Hurricane Page (More Tracking Information)
Clark Evans Track Model Plot of Earl (Animated!)
Clark Evans Intensity Model Plot of Earl (Animated!)
Clark Evans Top 10 Analog Storms for Earl
More model runs on from Jonathan Vigh's page
NRL Info on Earl -- RAMMB Info

Floater Satellite Images: Visible (Loop), IR [Loop), WV (Loop), Dvorak (Loop), AVN (Loop), RGB (Loop), Rainbow (Loop)

Fiona Event Related Links

Animated Skeetobite Model Plot of Fiona
SFWMD Model Plot (Animated Model Plot) SFWMD Hurricane Page (More Tracking Information)
Clark Evans Track Model Plot of Fiona (Animated!)
Clark Evans Intensity Model Plot of Fiona (Animated!)
Clark Evans Top 10 Analog Storms for Fiona
More model runs on from Jonathan Vigh's page
NRL Info on Fiona -- RAMMB Info

Floater Satellite Images: Visible (Loop), IR [Loop), WV (Loop), Dvorak (Loop), AVN (Loop), RGB (Loop), Rainbow (Loop)

Gaston Event Related Links

Animated Skeetobite Model Plot of Gaston
SFWMD Model Plot (Animated Model Plot) SFWMD Hurricane Page (More Tracking Information)
Clark Evans Track Model Plot of Gaston (Animated!)
Clark Evans Intensity Model Plot of Gaston (Animated!)
Clark Evans Top 10 Analog Storms for Gaston
More model runs on from Jonathan Vigh's page
NRL Info on Gaston -- RAMMB Info

Floater Satellite Images: Visible (Loop), IR [Loop), WV (Loop), Dvorak (Loop), AVN (Loop), RGB (Loop), Rainbow (Loop)



8:30PM EDT Update Wednesday 1 September 2010
Recon airfract has found a lower pressure in Earl of 932mb, which indicates Earl is continuing to strengthen.

Those still on the outer banks are highly recommended not to take the risk of a major storm approaching your area and leave.

Odds favor the center of it staying offshore, but the large size will still pound hurricane force winds along parts of the coast.






6:00PM EDT Update Wednesday 1 September 2010
Earl has continued to strengthen with maximum sustained winds reaching 135MPH and Tropical Depression 9 has become Gaston, the 7th tropical storm of the season.



Meanwhile Fiona is struggling and may not survive to the weekend. Since Gaston remains far from land, all eyes remain on Earl with Tropical Storm and Hurricane Watches and Warnings stretching from North Carolina to the New Hampshire border.

There is another wave just off Africa (east of Gaston) that we'll need to watch next week also.

10:30AM EDT Update Wednesday 1 September 2010
The wave in the Central Atlantic looks to be upgraded to Tropical Depression 9 at 11AM.

Hurricane Earl was re-upgraded to Category 4 status, and Earl is forecast to remain a major as it goes right next to the outer banks of north Carolina. With a storm of this size, I would not stay on the outer banks if you are there.


8AM EDT Update Wednesday 1 September 2010
Fiona has strengthened a bit since influence from Earl has been decreasing, it is now up to 60MPH Winds.

Chances for Development of the wave in the central Atlantic (98L) have gone up to 80%. This system would be named Gaston, and odds favor the more westerly track.

See original update for Earl information:



Original Update

Hurricane Earl has weakened a bit overnight due to dry air and small amounts of shear, but it is still a major hurricane. Earl is forecast to be at it's closest point to the outer banks of North Carolina Thursday night into Friday morning.

The majority of models keep Earl just offshore, but close enough to cause problems. A few, such as the NOGAPS take it inland into North Carolina. Those in the warning area, In short, prepare for the worst and hope for the best, and you should be looking at local advisories, officials, and Media.

The Hurricane Watches for North Carolina may be upgraded to Hurricane Warnings later today.

Those north of there along the coast will want to watch Earl closely for any changes or additional watches and warnings. Especially in Eastern Massachusetts/Cape Cod.

Those in Canada in the forecast track zone should begin to prepare as well.



Tropical Storm FIona is being caught up in the northerly flow from Earl, and currently is just offshore North and East of the Leeward islands, the official forecast takes it northward and eventually stalls near Bermuda, but there is some uncertainty with the forecast so the next day or two is critical for the eventual path of FIona. Fiona will likely stay weak, unless effects from Earl drop off quicker than expected or a center relocation southward happens. Fiona is still very much worth watching.

Tropical Storm warnings and Watches are up for the Leewards for Fiona.

Out east of both is the wave 98L, which now has a 50/50 shot at development over the next few days. Odds favor this going generally westward, so those in the Leewards, again, will have to watch it closely.

Another system just over the west side off Africa also has a chance to develop into next week, and odds favor it moving more westward (Ie not out to sea) as well.

Although the tropical Atlantic has become quite active in the past couple of weeks, a weakness between the Azores/Bermuda High and a Continental High over the Northeast has kept Tropical Storm Colin and Hurricane Danielle well out to sea and away from the east coast. The pattern is slowly changing and Hurricane Earl, while staying primarily at sea, is going to sideswipe the coast from North Carolina to Massachusetts before he moves inland over Nova Scotia.

At 5PM, Hurricane Earl was centered about 235 miles east of Great Abaco Island in the Bahamas. Earl was moving to the northwest at 17mph with sustained winds of 135mph and gusts to about 165mph - a Category IV major Hurricane. Hurricane Earl will continue to move northwest and then north as it comes under the influence of a trough of low pressure moving through the midwest that will eventually shove the storm off to the north northeast at an increased rate of forward speed while wind shear and cooler waters will slowly weaken the hurricane as it moves north northeast just offshore. A convergence zone could develop between the trough and the Hurricane and add some strong thunderstorms into the mix for western New England. Hurricane Earl should pass about 350 miles to the east northeast of east central Florida around midnight tonight. Earl should pass close to the Outer Banks of North Carolina in the early hours just after midnight on Friday morning and head north northeast - passing about 160 miles southeast of Springfield, Massachusetts, and 25 miles southeast of Chatham, Massachusetts, around midnight Friday night with tropical storm force winds extending about 125 miles to the northwest of the center at that time. Just a small shift to the west in the forecast track could bring hurricane and tropical storm conditions to a greater portion of the coast from North Carolina to southern New England. The following Warning and Watches are currently in effect:

Updated at 02/15Z, 11AM EDT:
A HURRICANE WARNING IS IN EFFECT FOR...
* BOGUE INLET NORTH CAROLINA NORTHEASTWARD TO THE NORTH
CAROLINA/VIRGINIA BORDER INCLUDING THE PAMLICO AND ALBEMARLE
SOUNDS.
* WESTPORT MASSACHUSETTS EASTWARD AROUND CAPE COD TO HULL INCLUDING
MARTHAS VINEYARD AND NANTUCKET ISLAND

A HURRICANE WATCH IS IN EFFECT FOR...
* NORTH OF THE NORTH CAROLINA/VIRGINIA BORDER TO CAPE HENLOPEN
DELAWARE.

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CAPE FEAR TO WEST OF BOGUE INLET NORTH CAROLINA.
* NORTH OF THE NORTH CAROLINA/VIRGINIA BORDER TO SANDY HOOK NEW
JERSEY...INCLUDING DELAWARE BAY SOUTH OF SLAUGHTER BEACH AND THE
CHESAPEAKE BAY SOUTH OF NEW POINT COMFORT.
* THE EASTERN PORTION OF LONG ISLAND NEW YORK FROM FIRE ISLAND INLET
TO PORT JEFFERSON HARBOR.
* NEW HAVEN CONNECTICUT TO WEST OF WESTPORT MASSACHUSETTS...
INCLUDING BLOCK ISLAND.

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* NORTH OF HULL MASSACHUSETTS TO EASTPORT MAINE.
* THE COAST OF NOVA SCOTIA FROM PORT MAITLAND TO MEDWAY HARBOUR.
* THE COAST OF LONG ISLAND WEST OF FIRE ISLAND INLET AND PORT
JEFFERSON HARBOR.

Folks along the east coast from North Carolina to Nova Scotia need to closely monitor the progress and track adjustments of Hurricane Earl and be prepared to follow the instructions of local Emergency Management personnel.

Tropical Storm Fiona was located 145 miles northeast of St. Thomas at 5PM moving to the northwest at 20mph with sustained winds of 60mph. Fiona should begin to move more to the north and remain at sea and slowly weaken, dissipating in four or five days just south of Bermuda.

Tropical Storm Gaston is a new tropical cyclone located over 1,600 miles east of the Lesser Antilles moving west at 15mph with sustained winds of 40mph gusting to 50mph. Gaston should maintain more of a southerly track as a strong high pressure ridge re-establishes itself over the Atlantic basin. Gaston should move west to west northwest and increase to hurricane strength by Sunday. Probably a system that will need to be monitored closely next week.

Yet another strong tropical wave exited the west African coast today (Wednesday) and it should intensify to a Tropical Depression by Friday or Saturday. The next name on the list is Hermine. Busy, busy! If a storm is heading your way - are you ready?
ED

General Characteristics:
The tropical Atlantic seems to be performing as expected, but there are some anomalies. A high pressure ridge off the southeast coast of the United States has shoved uncommonly dry air southward into the central Bahamas. Dry air associated with the Saharan Air Layer (SAL) has been a semi-permanent feature in the tropical eastern Atlantic this season and tropical waves that exit the west African continent have been stifled by that feature. An abundance of early season upper level lows and their associated shear zones have finally tailed off and the Basin has become a little more favorable for tropical cyclone development.

Hurricane Earl:
Although currently maintained as a Category IV storm, Earl is wrapping up an Eyewall Replacement Cycle and the sustained winds probably dipped to about 105 knots during the cycle, or Category III – still a Major Hurricane. At 31/15Z, Earl was located about 205 miles east of Grand Turk Island, still moving to the west northwest at a slower forward speed of 10 knots. Tropical Storm Warnings are posted for the Turks & Caicos Islands and a Tropical Storm Watch is in effect for the southeastern Bahamas. Earl will soon have to contend with some mighty dry air to his northwest and I’d anticipate a gradual weakening of the hurricane as the storm pushes northwestward. Earl should pass about 250 to 300 miles (probably closer to 300 miles) east of east central Florida on Thursday morning, be located just off the Outer Banks of North Carolina early Thursday morning and offshore Cape Cod early Saturday morning with landfall in Nova Scotia early Saturday afternoon – IF he can survive the dry air and increasing windshear. High waves with some coastal flooding and dangerous rip currents from the Bahamas and Florida northward into the Canadian Maritimes as the hurricane passes close to shore. Just a slight track adjustment to the west could bring dangerous hurricane conditions onshore, so folks from eastern North Carolina to eastern Massachusetts should monitor Hurricane Earl for any forecast changes. Its possible that Tropical Storm Watches could be initiated for some of those locations later today or this evening.

Tropical Storm Fiona:
At 31/15Z, TS Fiona was located about 440 miles east of the Leeward Islands moving west to west northwest at 20 knots. Sustained winds are still at 35 knots and not much change is expected with dry air still limiting structural integrity. Fiona should eventually move northwest into a weakness in the Atlantic ridge that will have been enhanced by the northward progression of Hurricane Earl. Fiona should pass just to the northeast of the northern Leeward Islands and remain well offshore of the eastern CONUS. Tropical Storm Warnings and Watches are posted for various locations in the Leeward Islands and these notifications will change as Fiona gets closer to the Islands.

Invest 98L:
Located southwest of the Cape Verde Islands near 12N 30W at 31/12Z, Invest 98L was moving to the west northwest at 15 knots with sustained winds of 25 knots. On Monday night, dry air to the north fully exposed a very well developed circulation center. The system should continue moving to the west to west northwest for the remainder of the week, but additional development will be on the slow side until about Friday – due to the proximity of the SAL to its north. Development chances should improve toward the end of the week.

Africa:
At 31/12Z, two well-developed tropical waves over Africa were located at 15N 4W and 15N 10E. The waves are a bit too far to the north and they will eventually exit the west African coast right into the teeth of the SAL, i.e., development not very likely.

Except for a convective flare-up in the southwestern Gulf of Mexico, the remainder of the Gulf and the entire Caribbean Sea have no tropical activity.
ED

I’ll start this off with a segment from the original ‘Statistics’ Blog back on August 13, 2006, when the season was running a little slow, when there had been a storm in June, July and August at that time, and when CSU had anticipated a total of 15 named storms for that season:

“I started to wonder what Climatology would think about this season if the next storm this year was not named until after August 25th - and the answers are interesting (if you like numbers). In the past 126 seasons, 74 of them did not have the 4th named storm until after August 25th. Nothing unusual there - seems like a common event, but what do the season totals look like when that happens?

Another interesting answer. The average season total is 8/5/2, with the highest seasons at 14/6/4 (1953) and 13/10/8 (1950). This means that in order for Colorado State (Dr Gray et al) to hit its revised forecast of 15 named storms this season, the next named storm must occur before August 26th...OR...the Atlantic basin must set a new record for season activity after August 25th.”

So here we are with another close to average starting season playing against an ultra-high seasonal forecast – and with the dialogue that a disparity of those numbers often generates. The problem is not so much in the season itself – so far its about average and it will probably end up that way. It is interesting to note that this year its not just the Atlantic basin that seems a little on the slow side – it’s the entire Northern Hemisphere with limited activity so far in EASTPAC and WESTPAC tropical cyclone areas.

As of August 20th, with regard to calendar days, the season is 44% complete. From the climatological standpoint of the total number of storms (on average) by August 20th vs the total number of storms overall, the season is 42% complete. Splitting the difference infers that there is 57% of the season remaining.

If, at the beginning of the season, your forecast was for 18 named storms this year (similar to the forecasts from CSU, TSR, WSI and NOAA), you now have 57% of the remaining season to achieve 83% of your forecasted total. With a forecast of 14 named storms, you have 57% of what remains of the season to develop about 78% of your storm total. While it is true that these statistics are results compared against an average season, it is also true that the season seldom extends beyond November 30th.

For reference purposes the 2006 season ended up at 9/4/2.
ED

I’ve observed some comments about the lack of tropical cyclone activity so far this season when compared against the high pre-season storm total forecasts. While I was one of the few that felt that this season would not be hyperactive (and I haven’t changed my thoughts on that), the season is far from over – in fact it has barely begun.

In the past (1880-2009), by July 25th only 13.3% of the total number of storms (1 May – 30 Nov) had been observed. That means the season still has about 87% to go, thus it is premature to suggest that the season is over. However, it is not premature to suggest that a hyperactive season of 18 or more named storms may not occur. Conditions in the Atlantic Basin are still quite hostile with significant areas of subtropical windshear, evidence of an active Saharan Air Layer (although it looks like it could finally be starting to wane), and a equatorial easterly low-level tradewind that continues to dive to the west southwest off the west African continent. Until these negative factors modify, the likelihood of having a new storm every week is pretty slim.

If you look at all of the storms since 1880 (all 1,223 of them) you don’t reach the halfway point in the season until September 16th. NHC defines that midpoint date as September 10th, but they only examine the totals during the satellite era (starting in 1966, although the era actually started in mid 1964). Twelve of the most active seasons (75% of the total) and one of the least active seasons (5% of the total) have occurred during the satellite era. Of the 130 seasons from 1880 – 2009, 12% had a seasonal total of 14 or more storms and 14% had a seasonal storm total of 5 or less. Since highly active seasons are just as uncommon as highly inactive seasons, the forecast skill for predicting either extreme is rather poor.

The average number of storms for the entire period (1880-2009) is 9. Using that long-term period, the average date for the first storm was July 3rd, the average date for the second storm was August 1st and the average date for the third storm was August 18th, so currently we are still ahead of the average based on the activity thus far this season. From 1965 – 2009 (that satellite era again) there have been exactly 500 storms in 45 years – and that’s where the current average of 11 named storms per year comes from.

The most active seasons were: 2005 (28), 1933 (21), 1887 and 1995 (19), 1969 (18), 1936, 2003 and 2008 (16), 1916, 2000, 2001, 2004 and 2007 (15), and 1953, 1990 and 1998 (14).

The least active seasons were: 1914 (1), 1930 (2), 1929 (3), 1883, 1884, 1890, 1917, 1925 and 1983 (4), and 1902, 1904, 1905, 1907, 1910, 1919, 1920, 1922, 1939 and 1962 (5).

Its interesting to note that low activity seasons can cluster into periods of multi-year inactivity just like active seasons can cluster into periods of multi-year increased activity – which does lend some support to the notion of a 25 year cycle (or a 20 year cycle, or whatever it turns out to be). In the long-range forecasting weather business, patience prevails.
ED

I’ll start this with a re-post of an article from June12, 2007:

“About a month ago I did a little research from a slightly different angle. Since ENSO conditions are only available from 1950, I decided to check El Nino Region 3.4 anomalies against all of the very active seasons since 1950. I defined an active season as 14 named storms or more (there have been 10 of these) and ENSO neutral conditions as anything from +0.5C to -0.5C. I used the average sea surface temperature anomaly for the three month period of May, June and July (figuring that a three month lag was reasonable between Pacific ENSO conditions and Atlantic activity). The results coincide nicely with the findings of Ostro & Lyons.

1953...14 storms...+0.4 anomaly
1969...17 storms...+0.4 anomaly
1990...14 storms...+0.3 anomaly
1995...19 storms...+0.1 anomaly
1998...14 storms...+0.1 anomaly
2000...14 storms...-0.6 anomaly (weakening La Nina)
2001...15 storms...+0.1 anomaly
2003...15 storms.....0.0 anomaly
2004...15 storms...+0.4 anomaly
2005...28 storms...+0.3 anomaly”

Since that 2007 post, we can add 2007 and 2008 to the list (and they both continued the association of an ENSO neutral SST anomaly in May/June/July with high-activity seasons). Note that it does not mean that ENSO neutral conditions in M/J/J will always yield a high-activity season – it just means that previous high-activity seasons (since 1950) almost always occurred when ENSO neutral conditions (-0.5C to +0.5C) were observed at the beginning of the season.

2007…15 storms…-0.1 anomaly
2008…16 storms…-0.4 anomaly

A few months ago, the April/May/June ENSO SST anomaly was forecast to be 0.0C, but it came in at +0.3C. The May/June/July forecast was -0.5C but so far it looks like it will end up closer to -0.2C. The implication is that the upcoming La Nina event was overforecasted, i.e., too soon and too strong.

There is no previous season since 1950 that matches the current season SST anomaly to date, and the SST anomaly outlook for the remainder of the current season. 1998 is about the closest season for an SST trend except that 1998 started with a stronger El Nino and ended with a strong La Nina. The storm totals in 1998 were 14/10/3. 1970 somewhat matches the expected SST outlook for the remainder of this season and the storm totals in 1970 were 10/5/2, but 1970 did not start with a robust El Nino.
ED