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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Quoting CaneWarning:


Tampa was even told we'd get over an inch today.

over to the west side of defuniak...just clouds and sun
Member Since: July 7, 2008 Posts: 0 Comments: 473
Quoting IKE:


This Afternoon: Showers and thunderstorms likely. Mostly cloudy, with a high near 92. Heat index values as high as 103. Southeast wind around 7 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Radar....



Well, that left a 40% chance of no rain. Happened where I live. We had an 80% chance of rain, and it didn't rain. We landed in that 20%!
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Quoting atmoaggie:

I was wondering when the RSO obs would show up. Thanks.
You get the messages too?


Neat, SRSO till almost 7:30.
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Quoting CatastrophicDL:
Anyone seen Patrap today? I'm missing his posts & pics.
He was on quite a bit this morning but I think he said he had to go out.
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Quoting atmoaggie:

Oh, I thought you guys were talking about what happens when you close your eyes. Cause that is what I see every time I do. Land, oceans, lats, lons...every time.


Hah! LOL!
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here in hollywood no rain sunny and beautiful
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Quoting WaterWitch11:


i don't know if anyone answered you but just hit the SHOW button in the frame to the right of their name

now if you can tell me how to get pictures in! YES i know copy and paste but go figure it does work for me


now that I re-read your question I see that I was of no help. sorry about that
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I've noticed it to the right/east also. The forcast track had it crossing the 20th latitude at 58.4 it seems now to cross at 57.4. Being picky-yes; being trivial-perhaps; In Bermuda and concerned with any move to the East- YUP.
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Post #601 thats a good one.
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614. Prgal
Quoting kmanislander:


You can solve that by deciding the length of loop you want to run but with a long loop obviously the track will then be an averaged track. With a long loop, line up the first couple of "rolls" with the last couple and ignore the ones in between that deviate in and out.

Very technical as you will see LOL

A bit technical but can be done, ty!
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ttttt
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Anyone seen Patrap today? I'm missing his posts & pics.
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Quoting Prgal:

The only problem I see with the technique is that its going to vary depending on the origin point. Is it a temporary wobble? Is it a trend? I have no idea!


You can solve that by deciding the length of loop you want to run but with a long loop obviously the track will then be an averaged track. With a long loop, line up the first couple of "rolls" with the last couple and ignore the ones in between that deviate in and out.

Very technical as you will see LOL
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609. IKE
Quoting CaneWarning:


Tampa was even told we'd get over an inch today.


This Afternoon: Showers and thunderstorms likely. Mostly cloudy, with a high near 92. Heat index values as high as 103. Southeast wind around 7 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Radar....

Member Since: June 9, 2005 Posts: 23 Comments: 37858
According to BenBIogger's handy chart it's going 306 degrees or NWbW.
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Quoting bam412:
so if we found a way to disrupt the circulation of this storm using chemicals/bombs etc, would we call the mission Operation Kill Bill?


No, no, Operation Tempest Storm!

Tempest Storm was a famous American stripper in the mid 1900's and performed for over 50 years.

And if anything was to be developed to try and alter these storms I think you'd need something that would "strip" the circulation, wind walls, so it might be apropos!
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Quoting nrtiwlnvragn:


At first I did also, but after a refresh they are there. Don't know why.

Oh, I thought you guys were talking about what happens when you close your eyes. Cause that is what I see every time I do. Land, oceans, lats, lons...every time.
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Quoting TexasHurricane:
Since I am new here to this blog this year, can you tell me why some post show and some don't? I can see some and then there are those that show just the username and not the post...


i don't know if anyone answered you but just hit the SHOW button in the frame to the right of their name

now if you can tell me how to get pictures in! YES i know copy and paste but go figure it does work for me
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Quoting philliesrock:
1-minute satellite updates for Bill...pretty cool stuff:

Link





Beautiful Image...
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Quoting philliesrock:
1-minute satellite updates for Bill...pretty cool stuff:

Link

I was wondering when the RSO obs would show up. Thanks.
You get the messages too?
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Quoting ftpiercecane:


You are right about that Ike, the local mets were calling for a rain filled day here but so far not a drop. Looks like good golf weather.

Meanwhile around here.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting Prgal:

I tried it in this loop http://www.ssd.noaa.gov/goes/flt/t2/flash-rb.html
It ended around 305 degrees using the image in post 530.
I tried it too and yes you are right. Looks like NNW.
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Quoting Prgal:

The only problem I see with the technique is that its going to vary depending on the origin point. Is it a temporary wobble? Is it a trend? I have no idea!


I think thats why he said short term?
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597. Prgal
Quoting IKE:


Hang on....let me measure it....


LMAO!!!
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Quoting reedzone:


I see nothing but land, ocean and latitude, longitude lines :)
Quoting IKE:


Hang on....let me measure it....



LOL nice!
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Quoting IKE:


Where's that heavy rain for Miami? It's up here in the panhandle...thunderstorm and 77 outside...here's the Miami radar...they blew that forecast big-time...



Tampa was even told we'd get over an inch today.
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Quoting reedzone:


I see nothing but land, ocean and latitude, longitude lines :)


At first I did also, but after a refresh they are there. Don't know why.
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593. Prgal
Quoting kmanislander:


The great thing about the " sheet of paper model " is that it never goes down with technical problems !!

The only problem I see with the technique is that its going to vary depending on the origin point. Is it a temporary wobble? Is it a trend? I have no idea!
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Quoting IKE:


Where's that heavy rain for Miami? It's up here in the panhandle...thunderstorm and 77 outside...here's the Miami radar...they blew that forecast big-time...



You are right about that Ike, the local mets were calling for a rain filled day here but so far not a drop. Looks like good golf weather.
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Quoting klaatuborada:
I know models are great, and I don't want to stir up anything, but the way I look at hurricanes is that at some point, they become a "living" thing. They have their own birth, development, path and eventually death, and that can't always be caught in a model. It's that nature part we can't predict, and rightly so.

Do love watching and studying it though, but makes it tough for those who want to be able to have total prior knowledge of what it's going to do. We've gotten better at our guessing, but each storm has it's own "personality" that throws that monkey-wrench into the game. Thus my earlier comment re: Schrodinger's Theory of Quantum Physics as Al Osborne used in in Rogue wave theory, and how it might be applicable in weather forecasting.


What's the difference between developing a 'theory' and developing a 'model' to help people predict states of nature?
::
GP
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Quoting reedzone:


It was a very small shift, in the same area in Canada, but bends a bit about 30 miles west near Cape Cod. Not really a big shift at all.


Unless you live there! LOL!
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1-minute satellite updates for Bill...pretty cool stuff:

Link
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Closest buoy readings to Bill that I have found.

41044 - MARITIME-buoy
Wednesday Aug. 19 - 18:50 UTCAir Temperature: 81°F
Dewpoint: 77°F
Wind: ENE at 36 mph
gusting to 45
Pressure: 1007.4 mb
Sea Surface Temp: 82.9°F
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586. IKE
Quoting reedzone:


It was a very small shift, in the same area in Canada, but bends a bit about 30 miles west near Cape Cod. Not really a big shift at all.


Hang on....let me measure it....

Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting nrtiwlnvragn:
18Z Models update



I see nothing but land, ocean and latitude, longitude lines :)

Nevermind!!!! I should have waited a bit longer for it to load lol.
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Quoting reedzone:


It's what the latest model runs are showing, things can change though. Just keep an eye on Bill.


My eyes have been on him since his start. Thanks! Predictably unpredictable.
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Quoting scott1968:


I was never going to openly admit that as well but what the heck. I'm in that number.


The great thing about the " sheet of paper model " is that it never goes down with technical problems !!
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Quoting IKE:


Looks the same to me...

00Z ECMWF...

12Z ECMWF...


It was a very small shift, in the same area in Canada, but bends a bit about 30 miles west near Cape Cod. Not really a big shift at all.
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18Z Models update

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Quoting scott1968:


I was never going to openly admit that as well but what the heck. I'm in that number.


Me too...I'll bet there are a number of us that do
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Quoting CloudGatherer:
The SFMR wind speeds, being the anomalous datum, were essentially ignored in setting the intensity. And I understand that.

But what I don't get is how the SFMR and the dropsondes could continue to miss the strongest winds over a three-day span. At what point does it become more likely that the actual readings, taken on the spot, are a better reflection of Bill's peak windspeeds?


In my mind, always. Dvorak T#s, and others, do have positive biases, at times. SFMR, too, but is usually only untrustworthy over very shallow waters.
Could be that advisory/discussion was a little bit liberal with the peak winds.
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576. Prgal
Quoting rwdobson:
Don't forget to use a protractor to give you the exact heading...all these tools from 4th grade come in handy.

LOL! I dont have one so my perception of it being in 305 degrees has a high error probability (or however its called) lol!
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Quoting nrtiwlnvragn:


It takes an understanding of each type of measurement and its limitations. For example dropsonde, in strong hurricanes you don't typicall use the surface splash wind, it is too turbulent (waves etc). Flight level also has considerations.


Thank you for those graphics; they're both quite useful. And I think the MBL guidance answers the question. Although the surface-level winds recorded have been relatively low, several dropsondes have found MBLs in the 115kt range.
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so if we found a way to disrupt the circulation of this storm using chemicals/bombs etc, would we call the mission Operation Kill Bill?
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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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