Bill intensifies to Category 4; globe has 5th warmest July on record

By: Dr. Jeff Masters , 3:28 PM GMT on August 19, 2009

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Category 4 Hurricane Bill is now the the fourth strongest tropical cyclone to appear on the planet so far this year, and may grow even stronger. Visible and infrared satellite imagery continue to show an impressive, well-organized, hurricane, with plenty of low-level spiral banding and upper-level outflow well-established on all sides except the west. On Bill's west side, upper-level winds from the west are creating a modest 10 knots of wind shear, which is giving the hurricane a bit of a squashed appearance there.

Wind shear is forecast to remain low to moderate, 5-15 knots, for the next four days. Sea Surface Temperatures (SSTs) will rise steadily from 28.5°C today to 29°C on Friday. Total ocean heat content is at a maximum today, and will gradually decline over the next four days. Bill should be able to take advantage of these favorable conditions a remain a major hurricane the next three days.


Figure 1. Visible satellite image from NASA's Aqua spacecraft at 12:40pm EDT Tuesday August 18, 2009. Image credit: NASA GSFC.

Water vapor satellite loops show a small "short-wave" trough of low pressure to the north-northwest of Bill, and this trough has turned Bill on a more northwesterly track over the past two days. Bill will miss the Lesser Antilles Islands, and the main impact of the hurricane on these islands will be high waves. The short wave trough (so called because it has a relatively small amplitude and wavelength) is not strong enough to turn Bill due north, and Bill is also expected to miss Bermuda. High waves and sustained winds of 20 - 30 mph are the worst that Bermuda is likely to get from Bill.


Figure 2. Visible satellite image of Bill's eye zoomed in, taken from NASA's Aqua spacecraft at 12:40pm EDT Tuesday August 18, 2009. Image credit: NASA GSFC.

An unusually strong "long wave" trough of low pressure (called long wave because of its large amplitude and wavelength) is expected to develop along the U.S. East Coast late this week. This trough will turn Bill to the north, and also bring high levels of wind shear in the 40 - 65 knot range on Sunday. Exactly where this turn occurs is still not clear. The models continue to be in two camps: an eastern camp (GFS, GFDL, HWRF, and ECMWF) that takes Bill 300 - 500 miles east of Cape Cod, and a more western camp (NOGAPS, UKMET) that bring Bill within 150 - 200 miles of Cape Cod. Both sets of models bring Bill ashore over the Canadian provinces of Newfoundland or Nova Scotia. Bill will be weakening rapidly as it makes landfall, and is likely to be a Category 1 hurricane if it hits Nova Scotia, or strong tropical storm if it hits Newfoundland.

Bill's big waves
Large swells from Bill will begin impacting the U.S. East coast from Florida to Maine beginning Friday night or Saturday morning. Seas will build to 5 - 10 feet in the offshore waters from central Florida northwards to South Carolina, and to 10 - 15 feet from North Carolina to Cape Cod. Near shore, waves will be about 40% less. This will cause a significant coastal erosion event along some portions of the coast. The latest run of the NOAA Wavewatch III model suggests that significant wave heights near Bill's center will reach 50 feet on Sunday. Since maximum wave height is typically about a factor of 1.9 greater than the significant wave height (which is the average trough-to-crest height of the top 1/3 largest waves), a few huge waves near Bill's center may reach 95 feet high.

Possible impacts to New England
The current set of computer model runs predicts that the center of Bill will pass Cape Cod, Massachusetts Sunday afternoon or evening. Tropical storm-force sustained winds of 39 mph or greater currently extend out 185 miles to the west of Bill's center, so that if Bill maintains its current wind distribution, Cape Cod could see sustained winds of about 40 mph Sunday night if the models predicting a more westerly path are correct. However, Bill will not keep this same radius of winds. The hurricane will weaken considerably beginning Sunday morning, once the storm gets caught up in the approaching long wave trough. High wind shear of 40 - 65 knots due to strong southwesterly winds aloft will act to compress the hurricane in the east-west direction, keeping the hurricane's strongest winds away from Cape Cod. The highest winds are likely to be no more than 30 mph on Cape Cod from Bill, if the storm follows the track of the western camp of models nearest to the Massachusetts. A few rain squalls may affect coastal Massachusetts, but the main impact of Bill on New England is likely to be coastal erosion from high waves.

Elsewhere in the tropics
The remains of Tropical Storm Ana are bringing scattered heavy rain showers to the Bahamas and Florida today. The remains are disorganized, and are not likely to re-develop. The only model calling for a new tropical cyclone to develop in the Atlantic over the next seven days is the GFS model, which predicts development off the coast of Africa about 7 days from now.

Fifth warmest July on record globally; a cold July in the U.S.
The globe recorded its fifth warmest July since record keeping began in 1880, according to NOAA's National Climatic Data Center. NOAA rated the period January - July 2009 as the sixth warmest such period on record. NASA's Goddard Institute for Space Studies rated July 2009 as the 2nd warmest July on record, behind July of 1998. For the second month in a row, global ocean Sea Surface Temperatures (SSTs) in July were the warmest on record, 0.59°C (1.06°F) above the 20th century average. This broke the previous July record set in 1998. The record July SSTs were due in part to an ongoing El Niño event in the Eastern Pacific, which has substantially warmed a large stretch of the tropical Eastern Pacific Ocean. As El Niño conditions mature during the coming months, near-record global ocean and land temperatures will probably continue. Now that El Niño conditions have been well-established for three months, the atmosphere has begun to heat up in response. It typically takes up to seven months for the atmosphere to heat up in response to ocean heating from an El Niño. This may explain why June of 2009, which independent assessments by NOAA, NASA, and the UK Hadley center agreed was the 2nd or 3rd warmest June on record at the surface, recorded only average satellite-measured temperatures in the lower atmosphere. In contrast, the July satellite-measured temperatures in the lower atmosphere were the 2nd or 3rd warmest on record, in agreement with the assessments that surface temperatures were the 2nd to 5th warmest on record.


Figure 3. Departure of temperature from average for July 2009. Image credit: NOAA/NCDC.

A cold July for the U.S.
For the contiguous U.S., the average July temperature of 23.1°C (73.5°F) was the coolest since 1994, and July temperatures were the 27th coolest in the 115-year record, according to the National Climatic Data Center. Ohio, Illinois, Indiana, Pennsylvania, Iowa, and West Virginia experienced their coolest ever July. Kentucky, Missouri, Michigan, and Wisconsin recorded their second coolest July in history. A strong trough of low pressure parked itself over the eastern portion of the U.S. in July, funneling down plenty of cold air from Canada. In the western U.S., a ridge of high pressure dominated, bringing unusually hot conditions. Arizona recorded its 3rd warmest July on record, and Seattle, Washington recorded its hottest day in history on July 28, notching a 103°F reading. This was 3°F above the previous record set in 1994.

U.S. precipitation was near average in July, with the month ranking 40th wettest in the 115-year record. U.S. tornado activity was above average in July, according to NOAA's Storm Prediction Center. However, no tornado deaths occurred in July.

At the end of July, 14% of the contiguous United States was in moderate-to-exceptional drought. This is a drop from the 19% figure observed at the beginning of the year. These extreme drought regions were exclusively in South and Central Texas.

I'll have an update Thursday morning.

Jeff Masters

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Our local met here in NC just said "life threatening rip currents" over the weekend, coastal flooding and some beach erosion for the outer banks...even though the center will be a couple hundred miles away!
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1722. IKE
Quoting Orcasystems:


I don't even want to know how I should take that remark


lol
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Im with you IKE I had 70 myself. Anywhere past that your going to be trying to throw a rock around a corner!
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Rare...remember the week of tomato soup?? I think this year will be clam chowder
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Quoting PcolaDan:

Be afraid, be VERY afraid.


(yes I found these and I'm having fun with them, it's all Orca's fault)


Those damn things are going to be jumping all around in my dreams.
Member Since: July 14, 2006 Posts: 0 Comments: 1144
Quoting medicroc:

This coming from you just sent me on a quick run to the bathroom


I don't even want to know how I should take that remark
Member Since: October 1, 2007 Posts: 81 Comments: 26511
1716. IKE
Quoting rareaire:
Ike what do you think is the drop dead lat for a safe recurve?


For the USA I would say 70W.

Bermuda is definitely going to get TS force winds, at least.

Member Since: June 9, 2005 Posts: 23 Comments: 37858
1715. centex
It's my understanding the NHC has not been given more money to improve forecast. Please correct me if I'm wrong.
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Bill is weakining a bit. I did not see anyone talk about hitting Cat 5 levels last night for a short. Never the less with Bill entering warmer SST's this weaking is probably short lived.

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Landfall points.... still one model that likes NY
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting Orcasystems:


OMG, another shift left.. that should be enough to get some people just panicking

This coming from Storm just sent me on a quick run to the bathroom
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Ike what do you think is the drop dead lat for a safe recurve?
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Bill

Bill

AOI
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting PcolaDan:

Depending on who you listen to, Ana either went west to the Yucatan, out to the middle of the Gulf, died over Cuba, or went north to Florida. Regardless, this all looks like normal August rains to me.
thanks Pcoladan...I wa sjust wondering...and thanks for that last minute thought there StormW...have a good nights rest...looking forward to your input tomorrow after that post...good night and God Bless to you and everyone.
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What could happen and what probably will happen its all in there!
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Quoting mossyhead:
we need someone to explain to us whats happening to bill.


read storm w's blog he pretty much summed up all the infor for you. And its a very good one today!
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#1693

Not good Storm--will be watching for your blog tomorrow. Thanks for the info
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1705. IKE
Center of Bill looks to be at 20.7N and 58.8W.

Just bumping along

That's the lowdown on Bill.

Member Since: June 9, 2005 Posts: 23 Comments: 37858
SSTs don't really cool below 26 degrees C until Bill would move north of North Carolina. There isn't that much real estate between NC and New England, especially if Bill were trucking.

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Quoting rareaire:
evening conch!


Hey Rare...storm just made a bunch of folks squirt a little :-0
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Models will continue to shift west.
Quoting weathersp:
Though the general trend is still NW... the periodic "jogs/wobbles" will add up in the end. To how much that ammounts to remains to be seen.

I estimate about 40 nautical miles, the current westward wobble, and still going.
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Quoting StormW:
Okay gang...time to turn in.

One last touch on Bill...recent satellite loop imagery would indicate he is beginning to recover from the EWRC. I've been analyzing water loop imagery, and here's my take...that first shortwave that was pulling on him is bye, bye. He is now heading for that second shortwave off the east coast. Looking at it, he could eat that too. I'm thinking once he gets closer to 65W, he should begin to slow his forward speed. I would almost look for another shift left in the guidance models.

I'll have another synopsis in the a.m.



OMG, another shift left.. that should be enough to get some people just panicking
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Four simple rules to live bye.

1. ALWAYS be prepared.
2. TRUST the models 48 hours out only.
3. DON'T focus on the little black line.
4. REFER to rule #1.
evening conch!
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Quoting PcolaDan:

Be afraid, be VERY afraid.


(yes I found these and I'm having fun with them, it's all Orca's fault)
we need someone to explain to us whats happening to bill.
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1696. centex
Side note: the 3 to 5 day cone is not 100% accurate. While they widen it they have not perfected that. 5 day cone violations can and will happen. Not saying in this case but they have a "tight 5 day cone".
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Question for those more knowledgeable. What would be the effect(if any)if the trough that is to kick Bill out to sea tilts strongly negative?
Thanks
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Quoting PcolaDan:

Be afraid, be VERY afraid.


(yes I found these and I'm having fun with them, it's all Orca's fault)


Umm I don't need any help getting in trouble.
Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting KATRINABILOXIGIRL:
please don't shoot me for asking this question, but what is that blob moving off of the west coast of Florida? is it what is left of the Ana situation? local met said we will be getting rainy days from the remnants of old Ana...just asking..thanks

Depending on who you listen to, Ana either went west to the Yucatan, out to the middle of the Gulf, died over Cuba, or went north to Florida. Regardless, this all looks like normal August rains to me.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting texascoastres:
People can survive with out electricity. When Galveston Island finally go electricity back 3 to 4 weeks later they still had no water or sewer systems or gas. All had been inundated with storm surge/sludge leaving them contaminated. With authorities not sure how to react. Not to mention being told you can't go home because they did not want people to see the true devestation of the storm. Not meaning the destruction of the property but the the effect it would have on an already emotionally beaten resident to see the human and animal remains left scattered by Ike. Not a pretty picture by no means but reality!


On the good side, they managed to get the Sonic up and running in just a few weeks...
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Quoting theshepherd:


YES thank you i love that one. blast from my childhood.
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Quoting washingaway:
Ike I don't remember you ever using smileys, with pom poms none the less. :)

Be afraid, be VERY afraid.


(yes I found these and I'm having fun with them, it's all Orca's fault)
Member Since: August 22, 2008 Posts: 12 Comments: 6010
1688. 7544
is s that ull still around or it further north now
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please don't shoot me for asking this question, but what is that blob moving off of the west coast of Florida? is it what is left of the Ana situation? local met said we will be getting rainy days from the remnants of old Ana...just asking..thanks
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People can survive with out electricity. When Galveston Island finally go electricity back 3 to 4 weeks later they still had no water or sewer systems or gas. All had been inundated with storm surge/sludge leaving them contaminated. With authorities not sure how to react. Not to mention being told you can't go home because they did not want people to see the true devestation of the storm. Not meaning the destruction of the property but the the effect it would have on an already emotionally beaten resident to see the human and animal remains left scattered by Ike. Not a pretty picture by no means but reality!
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Quoting WeatherCurious:
I am not sure how to ask this question and it is probably a very silly one, but I was wondering why individual thunderstorms form/develop where they do? I mean why is this cloud building up in this section of town and not the next section of town over? Is it hotter or colder at a certain location? Oh and I am not referring to the highs/lows mixing. I have that general idea down. I am referring to individual clouds. Sorry if this is not making sense I tried to make it as clear as possible.


although quite a few current facts do match up with this statement, I am skeptic only because it seems none of the big guns in meteorology will even talk about the remaining possibilities for an east coast landfall. Therefor, although I do have what I believe are realistic scenarios of how this could happen, I really would like a second opinion from somebody I know could be relied on.

As for this statement, we all know it is best to take something like this with a grain of salt until further confirmation.
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1682. centex
If it keeps the w woubles up the track will move S to NY. Sorry about that but we can't depend on 3-5 day forecast being 100% correct.
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Ike I don't remember you ever using smileys, with pom poms none the less. :)
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Quoting sullivanweather:
Looks like the eyewall is open in the northeast quadrant now.

whats happening to cause that?
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Hey,

Bill's cold cloud tops seem to be sacrificing themselves for better ouflow and a more annular appearance. Also, the pressure is dropping a lot again... last time it maintained its winds while dropping in pressure steadily was yesterday evening, and then the winds responded and it was suddenly on the brink of category 4 strength.
Could the same thing happen again? It seems like nothing's really going to stop it from doing so, Bill's looking at his most impressive yet.

And I'm hoping my relatives out in NS are taking Bill seriously, cosidering they are quite literally in the bullseye within day five.
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1678. amd
Quoting medicroc:

I've been on here about 4 years(I actually pay the ten bucks a year that's how much i think of this site!). There are a lot of good people here. Don't get discouraged. Enjoy!


agreed, i also have been a member for 4 years (although i mostly lurk, and only post when something major is going on). This site contains a lot of good information.
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From what the Hunters indicated, Bill was about to undergo an EWRC.
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1675. 7544
Quoting P451:


Thanks.

Ever figure out the problem with your computer? Or does it still choke on the graphics.


doing fine now it must have been the blog and not your graghs
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Quoting PcolaDan:

I'll see your and raise you a


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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.

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