Category 4 Earl headed for a close brush with North Carolina

By: Dr. Jeff Masters , 3:16 PM GMT on August 31, 2010

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Powerful Category 4 Hurricane Earl is pulling away from Puerto Rico and the northern Lesser Antilles Islands, and is eyeing its next potential landfall--North Carolina's Outer Banks. Earl brought heavy rain and high winds to Puerto Rico and much of the northern Lesser Antilles yesterday, though it appears that the islands were spared major damage. One exception may be Anegada in the British Virgin Islands, population 200. The eye of Earl passed just north of Anegada at noon yesterday, and Earl's south eyewall probably brought sustained winds of 100 mph to the island. Second hardest hit was probably Anguilla. Amateur weather observer Steve Donahue at anguilla-weather.com estimated gusts of 100 mph on Anguilla; his anemometer broke at 88 mph. Winds in St. Thomas in the U.S. Virgin Islands remained above tropical storm force (39 mph) for five hours yesterday afternoon, peaking at 52 mph, gusting to 62 mph, at 4:49 pm. Heavy rains hit Puerto Rico, where radar-estimated rainfall amounts of up to 5 - 7" occurred. Earl brought waves of sixteen feet to San Juan, and waves at buoy 41043 offshore of Puerto Rico reached 31 feet early this morning.


Figure 1. Morning satellite image of Earl, taken at 10:30am EDT 8/31/10. Image credit: NASA/GSFC.


Figure 2. Radar estimated rainfall for Earl from the San Juan, Puerto Rico radar. Isolated regions of 5 - 7 " of rain occurred in three locations on Puerto Rico. The rays fanning out to east from the radar location marked with a "+" are due to mountains blocking the view of the radar.

Intensity forecast for Earl
Wind shear as diagnosed by the latest SHIPS model forecast shows a moderate 10 - 20 knots of wind shear over Earl, due to upper level winds out of the southwest from a trough of low pressure to Earl's west. This moderate shear is predicted to continue through Friday, but should not appreciably affect Earl, since the hurricane is so large and strong. Ocean temperatures are a near-record 29.5 - 30°C, and very warm waters extend to great depth, resulting in a total ocean heat content favorable for intensification. Earl is undergoing an eyewall replacement cycle, which may diminish its winds by 10 -20 mph for a day or so. However, the storm will probably regain strength after completing this cycle, and it is likely Earl will be a major Category 3 or 4 hurricane at its closest approach to North Carolina Thursday night and Friday morning. By Friday night, 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 night, when it could potentially make landfall in Massachusetts. Earl is more likely to be a Category 1 hurricane on Saturday morning, when it could potentially make landfall in Maine or Nova Scotia, Canada.


Figure 3. Swath of surface winds from Earl predicted by the 2am EDT Tuesday, August 31, 2010 runs of NOAA's GFDL model (left) and HWRF model (right). Hurricane force winds (yellow colors, above 64 knots) are predicted to stay off the coast. Tropical storm force winds (light green colors, above 34 knots) are predicted to affect coastal North Carolina, Massachusetts, and Eastern Maine. Winds between 58 mph - 73 mph (dark green colors) are predicted to small portions of the coast. Image credit: Morris Bender, NOAA/GFDL.

Track forecast for Earl
The latest set of computer models runs from 2am EDT (6Z) this morning push Earl's projected track a little closer to the U.S. East Coast, and we now have two of our six reliable models predicting a U.S. landfall. The latest NOGAPS run shows Earl hitting the Outer Banks of North Carolina late Thursday night, then striking Southeast Massachusetts late Friday night, and Eastern Maine on Saturday morning. The HWRF model predicts a strike on Eastern Maine Saturday morning, but keeps Earl offshore from North Carolina and Massachusetts. None of the other computer models show Earl hitting the U.S., but several models bring Earl within 100 - 200 miles of North Carolina's Outer Banks and Southeast Massachusetts. It is likely that Earl will being a 12-hour period of heavy rain and tropical storm force winds of 39+ mph to North Carolina's Outer Banks, beginning on Thursday evening. NHC is giving Cape Hatteras a 12% chance of receiving hurricane force winds. By Friday evening, western Long Island, Rhode Island, and Southeast Massachusetts can expect a 6 - 8 hour period of heavy rain and tropical storm force winds of 39+ mph. NHC is giving Nantucket a 11% chance of receiving hurricane force winds. These odds are 4% for Boston, 6% for Providence, 5% for Eastport, Maine, and 11% for Yarmouth, Nova Scotia. 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. Keep in mind that the average error in position for a 3-day NHC forecast is 185 miles, which is about how far offshore Earl is predicted to be from Cape Hatteras three days from now. The average error in a 4-day forecast is 255 miles, which is about the distance Earl is expected to be from the coast of New England four days from now.

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 currents will be the rule, due to waves that will reach 10 - 15 feet in offshore waters. Waves from Hurricane Danielle killed two swimmers in the U.S. over the weekend and forced hundreds of water rescues along the U.S. East Coast. Earl's waves will be worse, and will likely cause millions of dollars in beach erosion damage.

Fiona
Tropical Storm Fiona is speeding west-northwest towards Hurricane Earl, but is unlikely to bring tropical storm force winds to the Lesser Antilles. Satellite loops show that heavy thunderstorm activity has increased in some of the outer bands this morning, but remains limited near the center. Wind shear is currently moderate, 10 - 15 knots, and the main impediment to development continues to be dry air associated with the Saharan Air Layer (SAL) surrounding the storm.

Forecast for Fiona
Fiona is moving quickly to the west-northwest, at about 24 mph. This means it is catching up to Earl, which is moving at 15 mph. By tonight, Fiona will be beneath Earl's upper-level outflow channel. Strong upper-level winds from Earl's upper-level outflow and a ridge of high pressure to the northwest of Fiona will bring high levels of wind shear, 20 - 30 knots, to Fiona tonight through Friday, and probably arrest the storm's development. The scenario now called for by all the models is for Fiona to be drawn into the low pressure wake of Earl and turn to the northwest. Fiona will pass to the northeast of the Lesser Antilles, and will probably not bring tropical storm force winds to the islands. Fiona should then continue to the northwest and then turn north, passing very close to Bermuda on Saturday morning. It is possible Earl could destroy Fiona through high wind shear before Saturday.


Figure 4. Morning satellite image of Fiona. High level cirrus clouds flowing out from the center of Earl as part of its upper level outflow can be seen starting to impinge upon the western side of Fiona's circulation.

Danielle is dead
Tropical Storm Danielle has succumbed to the cold North Atlantic waters, and is no longer a tropical storm.

98L
A new tropical wave (Invest 98L) moved off the coast of Africa yesterday, and is centered a few hundred miles south of the Cape Verdes Islands. Strong easterly winds from the African Monsoon are creating a moderate 10 - 20 knots of shear, and the disturbance is currently disorganized. A large area of dry air lies to the north and west of 98L, and this will interfere with development. The latest SHIPS model forecast predicts shear will remain moderate, 10 - 20 knots, for the next five days, and some slow development of 98L is possible as it moves westward at 15 mph. NHC is giving a 10% chance of this system developing into a tropical depression by Thursday, and none of the computer models develop it.


Figure 5. Morning satellite image of 98L.

A rare triple threat in the Western Pacific
Over in the Western Pacific, we have an unusual triple feature--three named storms all within 700 miles of each other. A 3-way interaction between these storms is occurring, making for a very tough forecast situation. The storm of most concern is Typhoon Kompasu, which hit Okinawa today as a Category 2 typhoon. Kompasu is expected to recurve northeastward and hit North Korea on Thursday as a Category 2 typhoon. It is unusual for a powerful typhoon to thread the tight Yellow Sea and hit North Korea, and I don't know how prepared they are for strong typhoons. Kompasu is expected to hit the most populous region of North Korea, but the country is pretty mountainous, and a significant storm surge disaster is probably unlikely. In the South China Sea, Tropical Storm Lionrock and Tropical Storm Namtheun are moving through the straights between Taiwan and China towards each other. Neither are predicted to develop into typhoons, but heavy rains are occurring in Guangdong and Fujian Provinces, further exacerbating the flood conditions China has suffered this summer.


Figure 6. An unusual triple feature over the Western Pacific--three simultaneous named storms all within 700 miles of each other. Image credit: NOAA/SSD.

"Hurricane Haven" airing again this afternoon
Tune into another airing of my live Internet radio show, "Hurricane Haven", at 4pm EDT today. Listeners will be able to call in and ask questions. The call in number is 415-983-2634, or you can post a question to broadcast@wunderground.com. Be sure to include "Hurricane Haven question" in the subject line.

Today's show will be about 45 minutes, and you can tune in at http://www.wunderground.com/wxradio/wubroadcast.h tml. The show will be recorded and stored as a podcast.

I may have a short update this afternoon, once the latest models runs are available.
Jeff Masters

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1033. CJ5
Fiona needs a shape change..quickly..lol
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1031. surfmom
Quoting StormJunkie:


Aye...Don't come messin' with the night shift ;)

One of the best times to be in here when there's an active storm out there. Some very intelligent folks, and lot's of opportunities to learn.


Thank YOU!!! I shuddered when he typed that and thought "be patient -- he just doesn't know...."

those waves heights by the PR buoy are frightening
though I'm sure the Big Wave Boys are waxing their boards

Earl seems a lot like IKE in disposition - Nasty & Needs careful watching -

back2wrk lurk
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I think that if you're looking for info about tropical weather and how it may effect you the smart thing to do is to listen to the following in this order:
1. NHC
2. Your local authorities
3. Dr. Masters
4. Anyone else of your choice on the Internet, be it weatherguy03, JB, Levi, StormW, me(lol), etc.
.
.
Use #3 and #4 to supplement what the NHC says. To me, this is just plain old fashioned good advice. Not knocking anybody, not even JB.
.
.
To each his own though, and if you want to trust your life/family/property to some guy on the Internet over the NHC, you can do that.
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Quoting Krycek1984:


Agreed...that is usually when I participate to avoid all this crap.

On a more tropical issue, is Earl really that far off forecast points? I see a lot of panic about it but I don't see many diagrams or graphics to support it. It would be interesting to see how its current track is comparing to its forecast track.
he is usually not far off the points because the nhc changes the points every 6 hours. if they never changed the cone, he would be hundreds of miles off the first cone of uncertainty
Member Since: June 29, 2007 Posts: 0 Comments: 1136
Earl



Trying refire more T'storms near the center..

Fiona



Trying to hang on!
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42 knt surface winds found in Fiona per recon
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1016. HadesGodWyvern (Mod)
Japan Meteorological Agency
Tropical Cyclone Advisory #39
TROPICAL STORM LIONROCK (T1006)
3:00 AM JST September 1 2010
================================

SUBJECT: Category One Typhoon In South China Sea

At 18:00 PM UTC, Tropical Storm Lionrock (990 hPa) located at 21.4N 119.0E has 10 minute sustained winds of 45 knots with gusts of 65 knots. The cyclone is reported as moving east northeast at 9 knots

Dvorak Intensity: T3.5

Gale Force Winds
================
140 NM from the center in southeast quadrant
100 NM from the center in northwest quadrant

Forecast and Intensity
========================
24 HRS: 23.3N 118.0E - 50 knots (CAT 2/Severe Tropical Storm)
48 HRS: 23.2N 115.0E - 35 knots (CAT 1/Tropical Storm)
72 HRS: 23.0N 112.0E - Tropical Depression
Member Since: Posts: Comments:
Quoting StormJunkie:


Aye...Don't come messin' with the night shift ;)

One of the best times to be in here when there's an active storm out there. Some very intelligent folks, and lot's of opportunities to learn.


Agreed...that is usually when I participate to avoid all this crap.

On a more tropical issue, is Earl really that far off forecast points? I see a lot of panic about it but I don't see many diagrams or graphics to support it. It would be interesting to see how its current track is comparing to its forecast track.
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Westward shift coming once again. NhC just needs 2 widen the cone some.
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looks as though NGFDL has changed.
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1006. IKE
Quoting hurricaneman123:


Earl looks like a disorganized CAT 3


He is looking a little sick this afternoon.
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Quoting Krycek1984:


How is it annoying? This whole blog has to go through a conversation about StormW, his credentials, and his personal life every day, it seems. It distracts from the issue at hand, which is tropical weather. If you want to wax poetic on the credibility of a certain blogger at least do it on the "night shift" when the blog isn't so active. It's just plain ignorance that we have to have this conversation every day...I wish more people would attempt to "police" the blog by pointing out the drama and stupidity so that less people get caught up in it!!!!


Aye...Don't come messin' with the night shift ;)

One of the best times to be in here when there's an active storm out there. Some very intelligent folks, and lot's of opportunities to learn.
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1004. xcool
Member Since: September 26, 2009 Posts: 2 Comments: 15620
Quoting Surfcropper:
I don't know about the rest of you, but I'd be scared if Hurricane Lionrock came around my neighborhood. Why can't the Atlantic region get more creative with storm names? I say we go Native American one year. Hurricane Running Bear...Tropical Storm Thunder Horse...Hurricane Bleeding Cloud



LOL! That is tooo funny!!! LOL!....Okay..back to lurking!
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Quoting FloridaHeat:


my opinion is you are making that up
No, they said the same thing yesterday.
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997. 2COOL
Quoting medicroc:

Please, to cut down on blog traffic at busy times, when you make a post like this please include source so you don't get a thousand requests for same. Thanks
Not saying anything one way or the other: the weather channel about 30 mins. ago.
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995. xcool
Member Since: September 26, 2009 Posts: 2 Comments: 15620
986
not in a million years
it'll never happen
Member Since: June 29, 2007 Posts: 0 Comments: 1136
Quoting btwntx08:
this does not look like a clean basin sry shows activity out there


nope
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Quoting Grecojdw:


And if someone had said to me the things he is saying about his years of experience and knowledge being all for nothing...I would be highly upset. Ridiculous statement if I say so myself:0


I tend to agree. My earlier post speaks for itself pretty much reguarding that subject.

The sad thing about this blog is that many knowledgable
respectable bloggers get the shaft and recieve no respect
and it gets frustrating at times. I would include myself in
that group as well,so i can speak from expierence.
Member Since: July 3, 2007 Posts: 0 Comments: 524
989. xcool
WHXX01 KWBC 311844
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1844 UTC TUE AUG 31 2010

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE INVEST (AL982010) 20100831 1800 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
100831 1800 100901 0600 100901 1800 100902 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 12.0N 31.0W 12.3N 33.6W 12.8N 36.1W 12.9N 38.3W
BAMD 12.0N 31.0W 12.6N 33.3W 13.3N 35.4W 14.0N 37.1W
BAMM 12.0N 31.0W 12.5N 33.5W 13.0N 35.8W 13.4N 37.7W
LBAR 12.0N 31.0W 12.7N 33.7W 13.6N 36.6W 14.1N 39.3W
SHIP 25KTS 27KTS 31KTS 36KTS
DSHP 25KTS 27KTS 31KTS 36KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
100902 1800 100903 1800 100904 1800 100905 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 13.1N 40.4W 13.6N 44.5W 14.7N 48.8W 16.1N 53.8W
BAMD 14.8N 38.3W 16.8N 41.3W 19.5N 44.5W 21.1N 47.3W
BAMM 13.8N 39.2W 14.8N 42.6W 16.4N 46.5W 18.1N 50.8W
LBAR 14.6N 41.7W 16.6N 45.6W 21.1N 48.4W 25.1N 48.7W
SHIP 39KTS 44KTS 45KTS 48KTS
DSHP 39KTS 44KTS 45KTS 48KTS

...INITIAL CONDITIONS...
LATCUR = 12.0N LONCUR = 31.0W DIRCUR = 295DEG SPDCUR = 16KT
LATM12 = 10.3N LONM12 = 28.0W DIRM12 = 289DEG SPDM12 = 16KT
LATM24 = 9.9N LONM24 = 25.1W
WNDCUR = 25KT RMAXWD = 45NM WNDM12 = 25KT
CENPRS = 1008MB OUTPRS = 1009MB OUTRAD = 180NM SDEPTH = S
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$
NNNN
Member Since: September 26, 2009 Posts: 2 Comments: 15620
Quoting jason2010xxxx:
5pm track has a 'possibly significant' westerly shift. I SAW THAT ON THE NHC PAGE.


Link?
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Dear Earl...

Please take your obstinate male self a little further to the East. I may have to start drinking if you don't. My 77 year old mother, 79 year old father, 1 poodle, 1 dachshund, 3 cats, a sister and brother in law who HAS to have a nap a 3:30 EVERY day may be more than I can bear. They all live at the beach in Delaware and that combined with a pre-menopausal single woman who has a 17 going on 35 year old roommate (AKA teenage daughter)and not been on a date in a year might just push me into the abyss.
<3 Tink
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can we stop the bs here and talk hurricanes.
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Looks like Earl moving nw could be a jog. Good news I'd say. But if that is a weak uul to his sw maybe temporary, definitely lot of dry air coming into west side of storm, looks to be reaching eye.
Member Since: August 18, 2008 Posts: 0 Comments: 3112
Quoting jason2010xxxx:
5pm track has a 'possibly significant' westerly shift. I SAW THAT ON THE NHC PAGE.
Show a link
Member Since: February 27, 2006 Posts: 0 Comments: 482


Earl looks like a disorganized CAT 3
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.