Category 4 Earl headed for a close brush with North Carolina

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

Share this Blog
5
+

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

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: 1533 - 1483

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 | 33Blog Index

It would totally suck if the OBX got nailed with Earl. To my knowledge they've never been hit by a high-end Cat 3 b4 ever, the damage would be incredible.
Member Since: Posts: Comments:
1532. Engine2
Quoting Capeskies:
Does anyone have a link to the latest NOGAPS model run?
http://raleighwx.easternuswx.com/models/nogaps/12znogaps500mbHGHTNAnogapsLoop.html
Member Since: Posts: Comments:
1531. KEEPEROFTHEGATE (Mod)
Member Since: Posts: Comments:
Quoting naitsabes:
yeah, but those guys do not know what they are talking about, the models are all wrong too; in addition, this storm is comming to Florida, I feel it, that is what you'll hear from many on the blog
Must be arthritis that you must be feeling. LOL
Member Since: Posts: Comments:
Does anyone have a link to the latest NOGAPS model run?
Member Since: Posts: Comments:
Quoting JRnOldsmar:
floodman - sorry here is the link...

Link


Thanks, by the way...whew, I was worried there for a minute
Member Since: August 2, 2006 Posts: 10 Comments: 9922
Hello my name is Earl....

I'm a west end boy...LOL
Member Since: Posts: Comments:
Quoting Zeec94:
Hurricane Watches in Effect from VA Beach, Virginia to the South Edge of North Carolina.


Not quite. Hurricane watches for NC coast from Onslow County northward. Tropical Storm watch from Cape Fear to Onslow County line. Nothing for NC from Cape Fear to SC line.
Member Since: Posts: Comments:
ok all this hype about the big west adjustment....lol
Member Since: Posts: Comments:
Hmm 98L looks like either we will have a red alert at 8pm or we have a red alert at 8pm and TD9 by 11pm
Member Since: Posts: Comments:
Quoting Floodman:


You would be well advised to do so; just the basic hurricane preparedness stuff: water, extra batteries, fill the gas tanks, that sort of thing...always better safe than sorry LOL
Apology excepted.Yep local mets are already talking about Earl.
Member Since: Posts: Comments:
Quoting Welling2000:
Washingtonian,

Flood's not being rude. He's being shocked about the Gulf Loop Current mention. Whatever could make you think he's being rude?


Thank you, Welling...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
1515. angiest
Quoting 954FtLCane:

that was not hundreds of miles, Charley was a jog....uggggg....really ..really.... come on y'all nuff of the westcasting, wishcasting, upcasting........uggggggggggggggggggggggg


The point being Charleston isn't in the clear until Earl has passed them. Until them they need to keep an eye on things.
Member Since: Posts: Comments:
ESTIMATED MINIMUM CENTRAL PRESSURE 940 MB
EYE DIAMETER 30 NM
MAX SUSTAINED WINDS 115 KT WITH GUSTS TO 140 KT.
64 KT....... 80NE 80SE 30SW 60NW.
50 KT.......120NE 120SE 60SW 90NW.
34 KT.......175NE 175SE 90SW 175NW.
12 FT SEAS..470NE 240SE 180SW 420NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

Hurricance Force windfield max. >60 + 80=140nm
Trop Storm force windfield max. >175 +175=350 nm
Member Since: Posts: Comments:
Quoting angiest:


Who was supposed to get Charley again?

that was not hundreds of miles, Charley was a jog....uggggg....really ..really.... come on y'all nuff of the westcasting, wishcasting, upcasting........uggggggggggggggggggggggg
Member Since: Posts: Comments:
1512. angiest
Quoting AstroHurricane001:
Noticed something interesting while collecting images for my own blog:



If you trace the tightly packed upper-level steering winds pushing to the east over Earl, they lead back to where Ike made landfall.


Oh hush. :)
Member Since: Posts: Comments:
Quoting Floodman:


You would be well advised to do so; just the basic hurricane preparedness stuff: water, extra batteries, fill the gas tanks, that sort of thing...always better safe than sorry LOL


Hurricane Prep Tips
Member Since: Posts: Comments:
1509. GetReal
double post...
Member Since: Posts: Comments:
1508. GetReal
Member Since: Posts: Comments:
Quoting CJ5:


Sorry, I responded on up further when corrected. I mean't blind in respect to that graphic. Didn't mean to come off smart arsed.
Thanks, it's all good. I've learned to take a moment before I post when perturbed.
Member Since: Posts: Comments:
1506. KEEPEROFTHEGATE (Mod)
Quoting yoboi:
where is earl going?
north
Member Since: Posts: Comments:
Can anyone tell me if in history of one storm being sucked into another, other than 1991 off NewEngland (perfect storm)? It looked today as though Fiona was going to run right into Earl.
Member Since: Posts: Comments:
Quoting Legion:
You can bet the over/under on named storms and hurricanes before the start of the season.
The bet on the degrees off on the forecast track would be more lucrative and volatile
Member Since: Posts: Comments:
Africa seems to have something aginst the atlantic basin now.It's moving out all these waves over the continent,and future Gaston looks very organized right now.The percentage should be raised at 8:00 to 30-40%.
Member Since: Posts: Comments:
Noticed something interesting while collecting images for my own blog:



If you trace the tightly packed upper-level steering winds pushing to the east over Earl, they lead back to where Ike made landfall.
Member Since: Posts: Comments:
1501. Engine2
18z GFS starting
Member Since: Posts: Comments:
Quoting washingtonian115:
Okay like maybe I was reading it incorrectly then?.And looky here looks like Earl is going to be in my backyard.Better start taking steps now even though I live in D.C


You would be well advised to do so; just the basic hurricane preparedness stuff: water, extra batteries, fill the gas tanks, that sort of thing...always better safe than sorry LOL
Member Since: August 2, 2006 Posts: 10 Comments: 9922
Quoting marmark:
or lose their butts.
That was more like it ...
Member Since: Posts: Comments:
1493. marmark
Quoting Flyairbird:
If internet gambling were legal.....One could make a fortune on betting on Earl..
or lose their butts.
Member Since: Posts: Comments:
Goodbye Fiona?
Member Since: Posts: Comments:
1489. marmark
Quoting SeVaSurfer:


Howards Pub will be busy the next few days. Wish I was down there with them having a few cold ones! They eat these storms for lunch down there!
Love that place! We ate there on our honeymoon!
Member Since: Posts: Comments:
If internet gambling were legal.....One could make a fortune on betting on Earl..
Member Since: Posts: Comments:
1486. angiest
Quoting 954FtLCane:

In the clear, y'all are pretty much safe, stop making a mountain off a a molehill.


Who was supposed to get Charley again?
Member Since: Posts: Comments:
Quoting washingtonian115:
You sound a little rude no?


I apologioze for sounding rude, but an interruption in the thermohaline circulation is catastrophe with global extinction level rammifications; I can assure you that it would be a considerably more newsworthy than this event seems to be. It appears, upon further examination, that the Franklin Eddy, an area of the circulation that typically breaks off the main loop current is what this refers to and that it has more to do with the slowing and early frift of the eddy and not the complete cessation of movement (that's a LOT of kinetic energy to be absorbed).

Again, I apologize for any perceived rudeness, but the question itself was inaccurate
Member Since: August 2, 2006 Posts: 10 Comments: 9922
Storm et'all, has anyone noticed that according to 2pm NHC track forecasts, Fiona and Earl will only be about by my estimate 400 miles from each other as of 2pm on Friday? From my understanding the Fujiwhara effect can start occurring at 900 miles so wouldn't this potentially cause Earl to slow down just as it reaches the OBX and since Earl is the larger of the two systems cause Fiona to turn toward the US East coast as Earl tries to absorb it?
Member Since: Posts: Comments:

Viewing: 1533 - 1483

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 | 33Blog 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.