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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524. Prgal
Quoting reedzone:


Nope, still WNW.. Even the NHC discussion says it's moving WNW.

At 11am...that was 4 hours ago. Maybe it started the turn, I dont know. That or my loops are broken...and Ike's too.
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Quoting StSimonsIslandGAGuy:
Bill is about the most "classic" looking hurricane since Isabel. We are very lucky it is forecast to thread the needle and pass well west of Bermuda and not bring destructive winds to the east coast. A little concerned about Nova Scotia, hope it doesn't turn into a Halifax howler!



Yea the north-east and the south-east side is a classic signature of a strong hurricane. The west side is not the best, probably telling us it will weaken over the next few days as it approaches high shear from the trough.

I saved a image of Bill because of its excellent structure to see later on before it weakens over the next 2days.
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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.
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486. Stormchaser2007 6:51 PM GMT on August 19, 2009
Apparently the NHC thinks the HH have been getting some good data.


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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 had the same question. Just go to the top(filter) drop down box and click "show all".
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Quoting Prgal:

I see the NW turn also. Those are great news, not for Bermunda tho.


Nope, still WNW.. Even the NHC discussion says it's moving WNW.
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517. Prgal
Quoting reedzone:
Bill is still moving West-Northwest.. Not north or west, or NNW.. Just WNW.

Maybe, but its evident that he is missing the forcast points and taking the east side of them. We will see.
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Quoting bcn:
Sorry, if I follow this NOAA link and selecting "Trop Pts", it displays a Cat1 after Nova Scotia ?


I see it that way too.... doesn't look good for Nova Scotia
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515. Prgal
Quoting IKE:


Could be...taken a turn more northwesterly.

I see the NW turn also. Those are great news, not for Bermunda tho.
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Quoting atmoaggie:

Huh. The last memo I saw says:
"First there will be a comet that falls from the sky,
followed by meteor showers and tidal waves,
followed by fault lines that cannot sit still,
followed by millions of dumbfounded dip-$#!ts.
And some say the end is near.


Huh. Because mine begins with an earthquake:

"The Earth will shake
In two will break
And death all around
Will be your dowry"

;)

Quoting CScyclone:
SOMEBODY PLEASE TELL ME what exactly the ensemble models are... because they are pushed extremely far west, a few of them are predicting land fall in conn/mass.


The GFS ensemble runs are what you get when you run the GFS under a variety of slightly tweaked initial conditions. It gives you a good idea of how unpredictability can throw things off in different directions.

And yes, they've gotten worse, and they're not pretty
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Quoting WatchingThisOne:


Yes atmoaggie - thank you. I read both of those. I'm pretty sure you understand what I am getting at.


The data could have been during an eye wall cycle and winds might not be as high during these cycles.
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Quoting lurkn4yrs:


scott1968---

Fine.. To funny.. Just trying to make sense of some people but.... (not working)


Yeah good luck with that. I just usually lurk to read a few of the bloggers post that I feel know what they are talking about. I read the rest of the junk for entertainment purposes only. lol
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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...
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He is a friendly fella... Dont you gouys see...
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Bill is still moving West-Northwest.. Not north or west, or NNW.. Just WNW.
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Quoting nrtiwlnvragn:
Initial 18Z update

AL 03 2009081918 BEST 0 193N 569W 115 947 HU


Maintains intensity at 115 kt. Movement is 305 deg at 20 mph.
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Stop quoting trolls who want it to hit Florida or enter the GOM.

Quoting JeffMasters:


A hurricane can break through a short wave trough or upper-level cold low, although the passage will weaken it. A hurricane cannot break through a major long wave trough like the one approaching Bill this weekend. In some cases, a long wave trough will move too quickly or not extend far enough south to fully recurve a hurricane, leaving the hurricane behind after the trough passes. That will not be the case with this weekend's trough, which is unusually strong will reach unusually far south for this time of year.

Jeff Masters


The storm is almost north of PR already. Bill will be way off to the north-east of Florida by Friday night.
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Quoting IKE:


Could be...taken a turn more northwesterly.

It could also be that it is moving more quickly than forecasted
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This was also freaky with Wilma as well

Number 2 in eye
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501. IKE
Quoting weathermanwannabe:


Hey Ike....Really bad news for Bermuda if that trend continues..


Could be...taken a turn more northwesterly.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting atmoaggie:

See 448 and 435.


Yes atmoaggie - thank you. I read both of those. I'm pretty sure you understand what I am getting at.
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Quoting WatchingThisOne:


That is exactly what I am trying to figure out.


The SFMR is off, way off. No way it a Category 1 with a Category 4 pressure.
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497. Prgal
Quoting Stormchaser2007:
Apparently the NHC thinks the HH have been getting some good data.

000
WTNT43 KNHC 191445
TCDAT3
HURRICANE BILL DISCUSSION NUMBER 17
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009
1100 AM AST WED AUG 19 2009

A NOAA P-3 PLANE ON A RESEARCH MISSION HAS BEEN PROVIDING EXCELLENT
DATA FROM BILL DURING THE PAST SEVERAL HOURS.

I think they meant the plane. The P-3 plane is not the one they usually use if I am not mistaken.
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Quoting klaatuborada:
Hey Dakster - you're right, it's funny how technology has advanced in the past 18 years. But even funnier is that weather prediction accuracy is about the same! ha ha! Well, at least here on the Cod, we're sticking out in the Atlantic, Gulf Stream to our South mixing up with the North Atlantic Current to the North, hard to predict anything here. It can be raining in Plymouth, 1 hour away over the bridge on the mainland, and glorious here, and vice versa. We've had blizzards dumping 4-5 feet of snow on us, but over the bridge, nothing. As I said, we're lucky if the weather forecasts for the Cape are 40% accurate. Don't go by Boston weather, or Providence RI, we're our own little weather anomoly.

Bill's going to turn more to the North now. I've been praying.


You must be in your own little micro-climate. I, too, hope for the best. At the moment I am very confident that SE FL is out of any danger.

Ohh, and I get the same thing here only it is my back and front yard. (no snow though) I can be raining in the front yard, but not the back yard and vice versa.
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495. bcn
Sorry, if I follow this NOAA link and selecting "Trop Pts", it displays a Cat1 after Nova Scotia ?
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Quoting adjusterx:


Put one more eye in there and he'll look like a bowling ball.


Hurricane Wilma after crossing Florida had 2 eyes, it was freaky
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Quoting IKE:
Bill is going east of the tropical forecast points....


Hey Ike....Really bad news for Bermuda if that trend continues..
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Quoting TexasHurricane:


Yeah, I see that...What is that about?


Two separate time sequences were used. Thus two eyes.
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491. IKE
Bill is going east of the tropical forecast points....
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting K8eCane:


and now at 20 mph?


Not sure.. but if that's true, the faster it moves, the more "west" it gets.. Is this what the models are trying to show? A faster storm? Interesting stuff.
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Quoting CaicosRetiredSailor:


?????
two eyes are better than one...


Put one more eye in there and he'll look like a bowling ball.
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scott1968---

Fine.. To funny.. Just trying to make sense of some people but.... (not working)
Member Since: August 15, 2009 Posts: 0 Comments: 90
Quoting CaicosRetiredSailor:


?????
two eyes are better than one...


Yeah, I see that...What is that about?
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Apparently the NHC thinks the HH have been getting some good data.

000
WTNT43 KNHC 191445
TCDAT3
HURRICANE BILL DISCUSSION NUMBER 17
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL032009
1100 AM AST WED AUG 19 2009

A NOAA P-3 PLANE ON A RESEARCH MISSION HAS BEEN PROVIDING EXCELLENT
DATA FROM BILL DURING THE PAST SEVERAL HOURS.
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"It is amazing how far we have come in 18 years. That official plotting chart looks ancient. Of course, the "internet" was in its infancy and most of us that were computer savvy were logging on to Prodigy, CompuServe, AOL, or locally run BBS's through 14.4k modems."

I remember doing this to connect to the proto-wunderground at work...1992 or so...

C: telnet weather.umich.edu



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Quoting bingcrosby:
The continuous slight jogs to the west on the models is disheartening. A pattern possibly?


Please. Can you back this up with lets say hummm DATA!! Show me some model runs and then we can talk.
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483. HadesGodWyvern (Mod)
Japan Meteorological Agency
Tropical Cyclone Advisory #23
TYPHOON VAMCO (T0910)
3:00 AM JST August 20 2009
=========================================

SUBJECT: Category Four Typhoon South-southeast Of Minamitori-sima

At 18:00 PM UTC, Typhoon Vamco (965 hPa) located at 18.2N 157.5E has 10 minute sustained winds of 85 knots with gusts of 120 knots. The typhoon is reported as moving north-northwest slowly

RSMC Dvorak Intensity: T5.5

Storm-Force Winds
================
50 NM from the center

Gale-Force Winds
===============
180 NM from the center in northeastern quadrant
140 NM from the center in southwestern quadrant

Forecast and Intensity
=====================
24 HRS: 19.5N 157.3E - 95 knots (Cat 4/Typhoon)
48 HRS: 21.9N 156.5E - 95 knots (Cat 4/Typhoon)
72 HRS: 25.4N 155.0E - 95 knots (Cat 4/Typhoon)
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Quoting reedzone:
Hurricane Bill is still moving West-Northwest.. Not NNW, North, or West. West-Northwest as it's forecast says.


and now at 20 mph?
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Quoting CScyclone:
SOMEBODY PLEASE TELL ME what exactly the ensemble models are... because they are pushed extremely far west, a few of them are predicting land fall in conn/mass.


Ensemble models just is a bunch of GFS runs, but all include slightly different conditions. This way you get to see the range of possibilities. So some of them are always going to be outside the range of what other models are predicting.
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Quoting lurkn4yrs:
apocalyps2

In a weird way I understand what you're doing I just think you are going about it in an annoying way..

I think some people do need to be feared into actually preparing.. Especially us in S.FLA who have become so use to not getting any storms that people actually think they are being protected by some magical bubble.. That is what happened when Andrew hit no one prepared and were laughing at the storm until it was knocking at their door.. Personally most of the people I know or talk to don't even have the basic hurricane supplies..

You are just over pushing the issue and people are going to do whatever they want regardless.


How you doing? (stupid Joey sounding voice)
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Quoting atmoaggie:

A little early to say EWRC, but the last frame or 2 hint at it.


I believe you are right...
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Quoting WatchingThisOne:


That is exactly what I am trying to figure out.

See 448 and 435.
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Hey Dakster - you're right, it's funny how technology has advanced in the past 18 years. But even funnier is that weather prediction accuracy is about the same! ha ha! Well, at least here on the Cod, we're sticking out in the Atlantic, Gulf Stream to our South mixing up with the North Atlantic Current to the North, hard to predict anything here. It can be raining in Plymouth, 1 hour away over the bridge on the mainland, and glorious here, and vice versa. We've had blizzards dumping 4-5 feet of snow on us, but over the bridge, nothing. As I said, we're lucky if the weather forecasts for the Cape are 40% accurate. Don't go by Boston weather, or Providence RI, we're our own little weather anomoly.

Bill's going to turn more to the North now. I've been praying.
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Link

Can some please help me understand how I read this and still come to the conclusion it's not going to hit the North East? I understand the trough, I just don't see how it's going to move Bill out (like the BAMM model is predicting). BTW- I'm starting a "lurkn4years" fan club...
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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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