Category 3 Hurricane Earl pounding northern Lesser Antilles and Puerto Rico

By: Dr. Jeff Masters , 2:40 PM GMT on August 30, 2010

Share this Blog
5
+

An intensifying Hurricane Earl is pounding Puerto Rico and northern Lesser Antilles Islands with heavy rain and high winds this morning. The eye of Earl passed just north of Anguilla at 9am EDT, and Juliana airport on neighboring St. Martin Island recorded sustained winds of 47 mph, gusting to 68 mph at 8am EDT before going silent. An Air Force Hurricane Hunter aircraft currently in Earl just found a central pressure of 960 mb at 9:42 am EDT. This is a significant drop of 25 mb in 25 hours. Top flight level winds at 10,000 feet seen by the Air Force aircraft were 128 mph. Using the usual rule of thumb that the surface winds are 90% of the 10,000 foot flight level winds gives one surface winds of 115 mph, which is right at the border of Cat 2/ Cat 3 strength. Top winds seen at the surface by the Air Force's SFMR instrument were lower, 104 mph. Recent satellite imagery shows that Earl is not perfectly symmetrical--there is still fewer heavy thunderstorms on the hurricane's north side, suggesting that upper-level northerly winds are bringing 5 - 10 knots of wind shear to the storm.


Figure 1. Radar image of Earl taken at 7am EDT 8/30/10 from the St. Maarten radar. Image credit: Meteorological Service of the Netherlands Antilles and Aruba.

Outlook for the Caribbean islands today
Latest radar animations out of Puerto Rico and St. Marten show that the eye of Earl is on track to pass just to the northeast of the islands of Anguilla, St. Maarten, and The Settlement in the British Virgin Islands today. The periphery of Earl's southern eyewall will probably bring Category 1 hurricane conditions to some of these islands today. NHC is giving its highest odds for hurricane-force winds to Saint Maarten--a 99% chance. These odds are 4% for St. Thomas in the Virgin Islands, and 2% for San Juan, Puerto Rico. The main threat to Puerto Rico will be heavy rains--up to eight inches in isolated areas. Earl's rains, in addition to causing flooding and dangerous landslides, will also help alleviate drought conditions that have affected many of the islands this year.

Intensity forecast for Earl
Wind shear as diagnosed by the latest SHIPS model forecast is nearly non-existent over Earl--just 3 knots--put is probably higher than that, based on the fact that the northern portion of Earl cloud pattern is ragged. Further evidence of this is the fact that Earl's eyewall had a gap in its west side, according to the latest report from the Hurricane Hunters. Ocean temperatures are a near-record 30°C, and very warm waters extend to great depth, resulting in a total ocean heat content highly favorable for rapid intensification. These nearly ideal conditions for intensification should bring Earl to Category 4 strength by Tuesday morning, and Category 5 is not out of the question. Earl should be able to maintain major hurricane status through Thursday, when it will make its closest approach to North Carolina. Sea surface temperatures are very warm, 29°C, along the U.S. East Coast, and wind shear is expected to remain low through Thursday. By Friday, when Earl will be making its closest approach to New England, wind shear will rise to a high 20 - 30 knots and ocean temperatures will plunge to 20°C, resulting in considerable weakening. Earl will still probably be a Category 2 hurricane on Friday, when it could potentially make landfall in Massachusetts or Nova Scotia, Canada.


Figure 2. Swath of surface winds from Earl predicted by the 2am EDT Monday August 30, 2010 run of NOAA's GFDL model. Hurricane force winds (yellow colors, 64 kt and above) are predicted to stay off the coast and tropical storm force winds (light green colors, 34 knots and above) are predicted to stay off the U.S. coast, but affect the coast of Canada. Image credit: Morris Bender, NOAA/GFDL.

Track forecast for Earl
Once Earl passes the Lesser Antilles, steering currents favor a northwesterly course towards North Carolina. History suggests that a storm in Earl's current location has a 25% chance of making landfall on the U.S. East Coast, and Earl's chances of making a U.S. landfall are probably close to that. None of the computer models show Earl hitting the U.S., but the storm will likely come uncomfortably close to North Carolina's Outer Banks and to Massachusetts. The latest set of model runs (2am EDT, or 6Z) project Earl will miss North Carolina by 200 - 300 miles on Thursday, and Massachusetts by a similar distance on Friday. Keep in mind that the average error in a 4 - 5 day NHC forecast is 200 - 300 miles, so the East Coast cannot breathe easily yet. The Outer Banks of North Carolina and Cape Cod, Massachusetts are both at the edge of the cone of uncertainty. NHC is giving Cape Hatteras a 9% chance of receiving hurricane force winds. These odds are 14% for Nantucket, 4% for Boston, and 2% for New York City. The main determinant of whether Earl hits the U.S. or not is a strong trough of low pressure predicted to move off the U.S. East Coast Friday. This trough, if it develops as predicted, should be strong enough to recurve Earl out to sea late in the week, with the storm just missing landfall in the U.S., but possibly making landfall in Nova Scotia, Canada.

Regardless of Earl's exact track, the U.S. East Coast can expect a long period of high waves beginning on Thursday. Significant beach erosion and dangerous rip current will be the rule, due to waves that will reach 10 - 15 feet in offshore waters (Figure 3.)


Figure 3. Wave forecast for 8am Friday, September 3, 2010, as produced by the 8pm EDT August 29 run of NOAA's Wavewatch III model. The model is predicting waves of 4 - 5 meters (13 - 16 feet) in the offshore waters from North Carolina to New Jersey.

Hurricane History for the northern Lesser Antilles
The last Cape Verdes-type hurricane to affect the Barbuda and the surrounding northern Lesser Antilles Islands was Hurricane Debby of 2000, which passed over the islands on August 28 as a Category 1 hurricane. Damage was less than $1 million, and no fatalities were reported. The last hurricane of any kind to pass through the northern Lesser Antilles Islands was Category 4 Hurricane Omar, on October 16, 2008. Omar took an unusual track, moving towards the northeast, and the storm's eyewall missed all of the islands. Omar did $80 million in damage to the Caribbean, mainly on the islands of Antigua, Barbuda, Dominica, the SSS Islands (Saba, St. Eustatius, and St. Maarten), and the U.S. Virgin Islands. No direct deaths were attributed to Omar, and the name Omar was not retired from the 6-year rotating list of hurricane names.

Links to track Earl
Wundermap of the northern Lesser Antilles Islands
Long range radar out of San Juan, Puerto Rico
Visible rapid scan satellite loop

97L
The tropical wave (Invest 97L) now 1000 miles east of the Lesser Antilles Islands has a well-defined surface circulation and enough heavy thunderstorms to be classified as a tropical depression, if it can maintain that state for another six or so hours. Satellite loops show the surface circulation clearly, but also that heavy thunderstorm activity has been slow to build. The storm is experiencing low wind shear of less than 5 knots, and is over warm 29°C waters. The main impediment to development continues to be dry air associated with the Saharan Air Layer (SAL) surrounding the storm. The latest SHIPS model forecast calls for shear to stay in the low range, 5 - 10 knots, through Tuesday, and this should allow 97L to organize into a tropical depression today or Tuesday. NHC is giving 97L a 90% chance of developing into a tropical depression by Wednesday.

97L is moving quickly to the west, at about 20 mph. This means it is catching up to Earl, which has slowed down to 14 mph. By Tuesday night, Earl is expected to be a large and powerful major hurricane with a well-developed upper-level outflow channel heading clockwise out from Earl's center at high altitudes. These strong upper-level winds will bring high levels of wind shear, 20 - 30 knots, to 97L, and probably arrest the storm's development. The most likely scenario depicted in the computer models is for 97L to be drawn into the low pressure wake of Earl and pass to the northeast of the Lesser Antilles. Earl would then eventually destroy 97L through high wind shear, and by robbing the storm of its moisture. An alternative scenario is that 97L will stay far enough away from Earl that it will be able to pass through the northern Lesser Antilles islands as a tropical storm on Wednesday and Thursday, then bend northwestwards to potentially threaten the Bahamas and U.S. East Coast. There is a very high degree of uncertainty on what may happen to 97L. History suggests that a storm in 97L's current location has a 25% chance of making landfall on the U.S. East Coast.


Figure 4. Morning satellite image of 97L.

Danielle
Hurricane Danielle is on its way to oblivion over the cold North Atlantic waters, and is only of concern to shipping interests.

Elsewhere in the Tropics
Over in the Western Pacific, tropical cyclone activity is ramping up, with two named storms expected to affect land this week. As is typical in a La Niña year, these storms have developed close to mainland Asia, and don't have a lot of time over water to intensify into strong typhoons. The storm of most concern is Typhoon Kompasu, which is expected to hit Okinawa today and recurve northward into Korea on Thursday. It now appears the Kompasu will not have major impacts on China's largest city, Shanghai. In the South China Sea, the fearsome sounding Tropical Storm Lionrock is forecast to hit the Chinese coast near Hong Kong on Tuesday, but is not predicted to develop into a typhoon.

The GFS model is predicting formation of a tropical depression off the coast of Africa about seven days from now.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 931 - 881

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43Blog Index

Quoting GBguy88:


Used to be in Navarre, Holley by the Sea. Pensacola now.


We're practically neighbors! Hopefully we can keep things out of the GOM this year but there's a long time to go with September and October ahead of us.
Member Since: Posts: Comments:
I think the ECMWF has been the best so far this year.
Member Since: June 29, 2007 Posts: 0 Comments: 1136
I'm out of here... will be back to plot the next HH run


AOI

AOI

AOI

AOI

AOI

AOI

TS BUSTED FORECAST ALIBI
Member Since: Posts: Comments:
I said last week that 97L was to be Fiona, and I'm sticking to it.
Member Since: Posts: Comments:
Quoting RecordSeason:
In the past several hours, the eye-wall presentation on radar has gone from green with spotty yellow, to yellow with a stripe of red,w ith just one green patch remaining on the NW side of the eyewall.

Additionally, all of the dry air has once again gotten out of the western eye wall.


Some of that is because its getting closer to the radar center.
Member Since: Posts: Comments:
Quoting angiest:


Colin was going to be a cat 3.


most of the models wanted Alex to go to Texas

they have been off by a pretty good amount all year long

they did nail Danielle though
Member Since: Posts: Comments:
Member Since: Posts: Comments:
Regardless of which model said what, I'd be getting ready if I lived in the Outer Banks, or anywhere along the mid-Atlantic coast for that matter. Even if the storm passes fairly well to the east, there is still the potential for some strong gusts and a measurable amount of water rise.
Member Since: Posts: Comments:
Radar is trying to show mesocyclones in the eyewall...
Member Since: August 26, 2006 Posts: 16 Comments: 4766
918. xcool


update Steering Layer 300-850mb
Member Since: Posts: Comments:
Quoting Floodman:


No need to panic...go to storm's blog, here and have a look at the latest...


Good idea!! lol ;)
Member Since: Posts: Comments:
Quoting RitaEvac:
"no model support" lmao, hell the models said Earl was going to go east of Bermuda at first, that haven't got Earl right the whole damn time! 97L model support was to head NW into never never land as soon as it came off Africa. Go stare at your models.


sometimes i think they should make models illegal until math gets to be so precise as to ratify a better percentage scenario in order to avoid all this "model worshiping"
Member Since: Posts: Comments:
Quoting connie1976:
hey Storm!! I'm getting a littly panicky.... Can I safely say that Earl will most likely miss South Florida? Thanks!! :)


No need to panic...go to storm's blog, here and have a look at the latest...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
Quoting RitaEvac:
"no model support" lmao, hell the models said Earl was going to go east of Bermuda at first, that haven't got Earl right the whole damn time! 97L model support was to head NW into never never land as soon as it came off Africa. Go stare at your models.


Colin was going to be a cat 3.
Member Since: August 26, 2006 Posts: 16 Comments: 4766
Quoting GBguy88:


Used to be in Navarre, Holley by the Sea. Pensacola now.


Ok gotcha..
Member Since: Posts: Comments:
Quoting FLPandhandleJG:


Hey thats close to me.. I live in BWB next to Niceville/Destin..


Used to be in Navarre, Holley by the Sea. Pensacola now.
Member Since: Posts: Comments:
"no model support" lmao, hell the models said Earl was going to go east of Bermuda at first, that haven't got Earl right the whole damn time! 97L model support was to head NW into never never land as soon as it came off Africa. Go stare at your models.
Member Since: Posts: Comments:
Quoting hurricaneman123:


isn't that about how close Danielle was to Earl?... and Earl is slowing down


Yes, roughly...unfortunately, it appears that Earl is actually picking up a little forward speed; most likely a wooble sort of thing, but it looks as tnhough he's moving about 2mph faster that the last time I checked...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
FROM:
http://www.stormcarib.com/reports/current/stmartin.shtml

Earl still battering St. Maarten
It' been going on for hours now. I took a little video from inside my house. the wind was too strong to open the door.

http://barcann.livejournal.com/190757.html
Member Since: Posts: Comments:
Quoting GBguy88:


Whenever I start to get bored of the rain we've been having, I ask myself, "Remember what it's like to be in the grip of a severe drought?" And then the rain seems rather pleasant :)


That's a good way to look at I guess, just wish it wasn't over the weekend, not too many boating weekends left this summer! Looks like Labor Day weekend will be nice once this front pushes through and clears the GOM out.
Member Since: Posts: Comments:
907. xcool
Member Since: Posts: Comments:
905. amd
latest Earl center location: 18.9667N 64.0333W
previous Earl center location: 18.8167N 63.7333W

That's a 0.15N 0.30W movement in one hour and 30 minutes time, or a movement of 22 miles. This is an exact WNW movement of 15 mph.

No slowdown, no speedup is occurring. Earl is following the NHC track just about exactly.
Member Since: Posts: Comments:
Quoting jason2010xxxx:


is that a silent clip, jason?
Member Since: Posts: Comments:
hey Storm!! I'm getting a littly panicky.... Can I safely say that Earl will most likely miss South Florida? Thanks!! :)
Member Since: Posts: Comments:
Quoting divdog:
no model support for that scenario.


none of the models took Earl this close to the northern islands when it first formed either
Member Since: Posts: Comments:
South Western Atlantic Bouy (41043)
Location: 20.989 North -65.014 West

Air Temperature: 81° F
Humidity: 77
Wind direction (W Dir): East (75 - 84 Degrees)
Wind Speed (W Spd): 29.2 kts (33.6 mph)
Wind Gust (W Spd): 36.9 kts (42.5 mph)
Dominant Wave Period (DWP): 14 sec
Dominant Wave Height (DWH): 23.95 ft
Dominant Wave Range (DWR): exactly 24.0 ft
Wind Wave Period (WWP): 8 sec
Wind Wave Height (WWH): 11.48 ft
Wind Wave Range (WWR): 10.66 - 12.30 ft
Wave Swell Period (WSP): 14 sec
Wave Swell Height (WSH): 21.33 ft
Wave Swell Range (WSR): 20.51 - 22.15 ft
Atmospheric Pressure (AP): 29.80 in
Member Since: Posts: Comments:
Quoting 69Viking:


Near Hurlburt Field in Fort Walton Beach South of Hwy 98 not far from the Sound.


Hey thats close to me.. I live in BWB next to Niceville/Destin..
Member Since: Posts: Comments:
898. xcool
Goldenblack "Welcome" ":)
Member Since: Posts: Comments:
Quoting *Floodman:




They are about 17 degrees apart; at this longitude, a degree of lattitude ia approximately 68 miles...17 8 68 is 1156; call it 1100 miles. They aren't THAT close!


Quoting hurricaneman123:


isn't that about how close Danielle was to Earl?... and Earl is slowing down


but i guess ur right... they're not that close
Member Since: Posts: Comments:
Quoting ILwthrfan:
I have heard a theory, I don't remember whom it was that gave the info out, but it was talked about how when the SST in the atlantic or East coast of the U.S. are well above normal AND the season also experiences a below average season in hurricanes, or "lack of track of hurricanes over a particular area" generally results in significant snowstorms for the east coast over that particular area of residual TCHP content.

Can the same be said about the gulf of mexico and corresponding southern and midwestern states winters? Thank you.
I don't know about that but last year and I noticed this year, the birds are migrating early. That is a clear sign of an early winter. Hopefully not as harsh as last year. It got so cold in the Keys we had a major fish kill of our tropical fish.
Member Since: Posts: Comments:
Quoting FLPandhandleJG:


I agree.. Where u eactly live..


Near Hurlburt Field in Fort Walton Beach South of Hwy 98 not far from the Sound.
Member Since: Posts: Comments:
what source you lookn at? link?
Member Since: Posts: Comments:
Quoting RitaEvac:
Earl speeds up, moves closer to US, 97L slip right underneath to cause terror in the Carribbean
no model support for that scenario.
Member Since: August 22, 2008 Posts: 0 Comments: 755
Quoting Floodman:




They are about 17 degrees apart; at this longitude, a degree of lattitude ia approximately 68 miles...17 8 68 is 1156; call it 1100 miles. They aren't THAT close!


you are correct, I can see Earls outflow being a slight issue for 97L, but I think the timing will work out for 97L due to the fact that Earl is going to be moving northward faster over the next 24-48; while 97L will begin to slow down in that time
Member Since: Posts: Comments:
97L circulation gonna survive, can be sheared all it wants from Earl, that's a hellava circulation spinning there and aint come all this way from Africa to poof out. Vigorous spins like 97L are ones to reckon with.
Member Since: Posts: Comments:
Quoting Floodman:




They are about 17 degrees apart; at this longitude, a degree of lattitude ia approximately 68 miles...17 8 68 is 1156; call it 1100 miles. They aren't THAT close!


But how long before 97L catches up to Earl? If two trains leave Chicago...
Member Since: Posts: Comments:
Quoting Engine2:
Anyone know if Storm was able to finish his blog yet?


Just click his name...and find out
Member Since: Posts: Comments:
Quoting wpbdad:


I think he said this morning he had to take his son to the Doctor and when he got back he would do his blog.
sheri
Member Since: Posts: Comments:
Certainly possible. It'll be interesting to see where it projects it to go if it does allow it to survive Earl. 36 hours ago it was through Florida, 24 hours ago through Cuba, and 12 hours ago following a track similar to Earl's.
Member Since: October 19, 2005 Posts: 0 Comments: 308
Quoting Floodman:




They are about 17 degrees apart; at this longitude, a degree of lattitude ia approximately 68 miles...17 8 68 is 1156; call it 1100 miles. They aren't THAT close!


isn't that about how close Danielle was to Earl?... and Earl is slowing down
Member Since: Posts: Comments:
LOL, thanks....I mean they went back like 80 posts to "prove me wrong"....I am still laughing.

Quoting xcool:
Goldenblack lolol
Member Since: Posts: Comments:
Tropical Storm force winds coming onshore right now on the east coast of Puerto Rico.
Member Since: Posts: Comments:
Quoting GBguy88:


Whenever I start to get bored of the rain we've been having, I ask myself, "Remember what it's like to be in the grip of a severe drought?" And then the rain seems rather pleasant :)


I agree with this in somewhat but u also have to think flooding could be a problem.. I live in low line area.. :(
Member Since: Posts: Comments:

Viewing: 931 - 881

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Mostly Cloudy
59 °F
Mostly Cloudy