Bill is gone; Invest 92 pops up

By: Dr. Jeff Masters , 2:08 PM GMT on August 24, 2009

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Hurricane Bill is no more. The hurricane swept past Canada's Nova Scotia province Sunday afternoon, then made landfall early this morning in southeastern Newfoundland as a borderline tropical storm/Category 1 hurricane. Bill's waves claimed two lives over the weekend, a 54-year old swimmer that drowned in Florida, and a 7-year old girl in Maine that got swept into the sea by a big wave. The first death of the 2009 Atlantic hurricane season occurred on August 16, when a swimmer drowned in the rough surf from Tropical Storm Claudette at Pananma City Beach, FL.

Nova Scotia misses a direct hit
The center of Bill scooted parallel to the coast of Nova Scotia Sunday afternoon, and never quite came onshore. Since the storm's forward speed was so rapid--about 35 mph--this resulted in a highly asymmetric wind distribution. Since the top winds of a hurricane include the forward motion of the storm, Bill's top winds of 85 mph observed in the offshore, right front quadrant of the storm meant that the winds on the weak side of the storm, over Nova Scotia, were 85 mph minus 35 mph, or just 50 mph. Winds along most of the coast stayed below 39 mph, the borderline for tropical storm-force winds. The strongest winds measured in Canada were at Sable Island, which lies 150 miles offshore of Nova Scotia. Winds on the island hit 61 mph, gusting to 77 mph, between 4 - 5 pm ADT Sunday afternoon. A few islands along the Nova Scotia coast, such as Beaver Island and Hart Island, reported sustained winds of 39 - 40 mph. The big story for Nova Scotia was the waves from Bill. Buoy 44258 at the mouth of Halifax Harbor recorded significant wave heights of 29.5 feet and maximum wave heights of 49 feet as Bill passed 50 miles offshore. The buoy recorded top sustained winds of 35 mph, gusting to 51 mph. The waves combined with a 1.5 - 3 foot storm surge flooded many coastal roads. Buoy 44150, about 160 miles offshore of of the southwest tip of Nova Scotia, was in the east eyewall of Bill between 10 - 11 am ADT, and reported sustained winds of 62 mph, gusting to 85 mph, with significant wave heights of 44 feet. The buoy recorded a maximum wave height of 87 feet, according to Environment Canada. The highest official rain report on Nova Scotia was 2.6" (65 mm) at Yarmouth. Rainfall cause some localized flooding and road damage. Bill's winds cut power to about 40,000 people at the height of the storm. At Peggys Cove, three men were hit by a giant wave but were not hurt. A gift shop and attached home in the village were swept off of their foundation.

Newfoundland gets hit, but damage is minor
The southeast corner of Newfoundland took a direct hit from Bill. The storm made landfall early this morning as a borderline tropical storm/Category 1 hurricane. Top winds on the island were measured at Cape Race, which recorded sustained winds of 58 mph, gusting to 76 mph, between 1:30 and 2:30 am NDT. A storm surge of 1.2 meters (4 feet) was estimated by Environment Canada for Placentia Bay where Bill made landfall. Damage was minor on Newfoundland, with no major flooding reported. Bill dumped up to three inches of rain on Newfoundland.


Figure 1. The eye of Hurricane Bill on August 19 at 2157 UTC, from a NOAA P-3 Hurricane Hunter aircraft flying at 10,000 feet. Photo credit: Jack Parrish of NOAA's Aircraft Operations Center.

Kelvin-Helmholtz instability waves in the eye of Bill
Flight Director Jack Parrish of NOAA's Aircraft Operations Center snapped a cool photo in the eye of Hurricane Bill on Friday, showing the existence of a Kelvin-Helmholtz instability wave (Figure 1). The photo was taken on August 19 at 2157 UTC, from a NOAA P-3 Hurricane Hunter aircraft flying at 10,000 feet. The photo is taken looking WNW towards the eyewall. The towering clouds of the eyewall extend up to 50,000 - 55,000 feet in the photo, and the ocean surface is not visible, due to stratocumulus clouds covering the bottom of the eye. The center of the photo shows that the top of one of these stratocumulus clouds has a feature that looks like a breaking wave in the ocean. Well, that is an example of a breaking wave in the atmosphere known as a Kelvin-Helmholtz instability wave. The atmosphere behaves as a fluid, and thus has wave-like motions. When there is a sudden change of wind speed along the top of a cloud (wind shear), the flow can become unstable and cause breaking waves to form. One can see Kelvin-Helmholtz in the sky several times per year, and several alert wunderphotographers have uploaded photos of these waves over the years. However, it is uncommon to see these waves in the stratocumulus clouds covering the eye of a hurricane.


Figure 2. Water vapor satellite image for 8:15 am EDT 8/24/09. A tropical wave is approaching the Northern Lesser Antilles Islands, but is running into high wind shear from an upper-level cold low to the west of it. Image credit: NOAA/SSD.

Tropical wave approaching Lesser Antilles becomes Invest 92
A tropical wave with a moderate amount of shower activity is moving west-northwest at 20 - 25 mph and is approaching the northern Lesser Antilles Islands. This wave was designated "Invest 92" (92L) by NHC this morning. The wave is under about 20 - 30 knots of wind shear due the strong upper-level winds from the west. These winds are being created by the counter-clockwise flow of air around an upper-level cold-cored low north of Puerto Rico (Figure 2). This low is expected to move west-southwest and slowly weaken over the next two days, allowing shear to drop to the moderate 10 - 20 knot range beginning Tuesday night, according to the SHIPS model. By Wednesday, the upper low is predicted to be weak enough and far enough away from 92L that it will have a chance to develop. Most of the models show some degree of development of 92L by Thursday, when it is expected to be a few hundred miles off the coast of South Carolina. This wave could turn northward and give a wet weekend to New England, though it is too early to be confident of this. NHC is giving 92L a low (less than 30% chance) of developing into a tropical depression by Wednesday morning. The upper-level low will create plenty of wind shear and dump cold, dry air into 92L over the next two days, so Wednesday is probably the earliest we can expect the system to begin organizing into a tropical depression.

Several models predict the development of a tropical wave coming off the coast of Africa late this week.

I'll have an update Tuesday.

Jeff Masters

Beach Wall wave 1 (BeachBecky)
Waves from Hurricane Bill crashing on the sea wall during high tide in Lynn, MA
Beach Wall wave 1
Hurricane Bill Waves Day 2 # 9 (RIWXPhoto)
Hurricane Bill Waves Day 2 # 9
Kelvin-Helmholtz Instabilities (btangy)
Kelvin-Helmholtz Instabilities to the S of Boston. Wavy like pattern in clouds is caused by a difference in winds between the cloud layer and the layer just above (called wind shear). The manifestation of this at the top of the altostratus deck is quite a beautiful and rare sight!
Kelvin-Helmholtz Instabilities

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Just stopping in for a bit this morning. Still expecting gradual development of 92L during the next day or so. Also expecting EPAC development of 93L, and the 00Z ECMWF had a storm forming as it moves into the CATL a bit later in the period.
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Blog very quiet right now.....I see not much change with 92L, and 93L is about to move over land. I still say Hawaii should not take their eye of Hilda yet. Even the CPHC says it is too early to say whether or not the NGFDL and the NOGAPS could be right. If they were Hawaii would be looking at a Cat. 1/2 landfalling Hurricane from Hilda (if those tracks verified) I'll be back later today.
Member Since: June 29, 2009 Posts: 13 Comments: 5315
thanks so much for the links, I am one that is always asking for links now I have months worth of trying to figure it all out now. Watch my brain grow!
Quoting TampaSpin:
Anyone that needs nearly anything as for as Models can find it on the Home page of WeatherUnderground. You can also try StormJunkie.com as he has a tab with all kinds of links. I also have a tab on my site that has nearly everything you need as Links to find nearly everything....

StormJunkie.com under the tab quick links

TampaSpinsWeather.webs.com under the tab weather links

Hope this helps some as many ask about where to find things.
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Whoa...I miss 1 day from this blog and I miss a lot. Space shuttle, 92L, 93L, another one in the MDR next week.
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Morning All -

ECMWF shows 92l going up the east coast and now has a CATL low at the end of its run, getting VERY interesting out there....

ECMWF

Also shows 93l becoming a storm in the Pacific!
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Quoting HadesGodWyvern:


right overland U.K. in the coming hours


I can already feel it. Instead of a rather humid day, their a chill in the air. Winds are about 10 mph sustained, with cloud and a few small showers.
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1488. HadesGodWyvern (Mod)


right overland U.K. in the coming hours
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Quoting HadesGodWyvern:
Central Pacific Hurricane Center
Tropical Cyclone Advisory #12
TROPICAL CYCLONE HILDA (EP112009)
9:00 AM UTC August 25 2009
=============================

At 6:00 AM UTC, Tropical Storm Hilda (1001 hPa) located at 14.8N 147.9W or 510 southeast of Hilo Hawaii has sustained winds of 50 knots with a gust of 60 knots. The cyclone is reported as moving west at 8 knots.

Gale/Storm-force Winds
==================
65 NM from the center

Forecast and Intensity
======================
12 HRS: - 14.7N 149.1W - 55 knots (Tropical Storm)
24 HRS: - 14.6N 150.6W - 55 knots (Tropical Storm)
48 HRS: - 14.2N 153.4W - 60 knots (Tropical Storm)
72 HRS: - 14.3N 156.2W - 65 knots (SSHS-1 Cyclone)


ooh a Hurricane in Cpac.
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1486. HadesGodWyvern (Mod)
India Meteorological Department
8:30 AM IST August 25 2009
===============================

A low pressure area has formed over northwest Bay of Bengal and adjoining coastal Orissa.
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1485. HadesGodWyvern (Mod)
Central Pacific Hurricane Center
Tropical Cyclone Advisory #12
TROPICAL CYCLONE HILDA (EP112009)
9:00 AM UTC August 25 2009
=============================

At 6:00 AM UTC, Tropical Storm Hilda (1001 hPa) located at 14.8N 147.9W or 510 southeast of Hilo Hawaii has sustained winds of 50 knots with a gust of 60 knots. The cyclone is reported as moving west at 8 knots.

Gale/Storm-force Winds
==================
65 NM from the center

Forecast and Intensity
======================
12 HRS: - 14.7N 149.1W - 55 knots (Tropical Storm)
24 HRS: - 14.6N 150.6W - 55 knots (Tropical Storm)
48 HRS: - 14.2N 153.4W - 60 knots (Tropical Storm)
72 HRS: - 14.3N 156.2W - 65 knots (SSHS-1 Cyclone)
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1484. HadesGodWyvern (Mod)
National Hurricane Center
Tropical Cyclone Advisory #3
TROPICAL CYCLONE IGNACIO (EP122009)
9:00 AM UTC August 25 2009
=============================

At 6:00 AM UTC, Tropical Storm Ignacio (1004 hPa) located at 18.1N 118.5W or 565 west-southwest of Southern Tip of Baja California Peninsula has sustained winds of 35 knots with gusts of 45 knots. The cyclone is reported as moving west-northwest at 10 knots.

Gale-force Winds
================
45 NM from the center

Forecast and Intensity
======================
12 HRS: - 18.7N 119.9W - 40 knots (Tropical Storm)
24 HRS: - 19.7N 122.0W - 45 knots (Tropical Storm)
48 HRS: - 23.0N 125.0W - 40 knots (Tropical Storm)
72 HRS: - 26.5N 128.5W - 30 knots (Tropical Depression)
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Great Bill is headed straight for me *crys*
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Great picture though.
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No wait, scratch that, NASA sayed that the launch was scrubbed today as a result of thunderstorm activity. Another try is scheduled tomorrow same time.
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Tomorrow at eleven 1:10 EDT or did it already happen? ONe of NASA's sites states that the launch will be tomorrow, yet anther states that it will be today. Can I get help on this?
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:(
Member Since: October 13, 2005 Posts: 4 Comments: 2156
This blog site seems too quiet, Ill start a conversation and Ill be available untill 3 a.m. Mountain Time. Ill be back with the tropical invest, and what everyone is refering to as a NASA mission. BRB
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Quoting msphar:
92L is already beyond my area of concern. Hence my focus on the MDR. I hope 92L doesn't grow but that is not where my concerns lie.


In that case, the GFS continues to hint at the possibility of tropical cyclogenesis with a tropical wave in the EATL a week or so from now.
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1476. msphar
92L is already beyond my area of concern. Hence my focus on the MDR. I hope 92L doesn't grow but that is not where my concerns lie.
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Quoting msphar:
So is there any thing of interest weatherwise out to the East of the islands ? Looks to my inexpert eyes that things will be quiet for the next several days out in the MDR. This season will be hardpressed to meet the forecast of the season predictions made by the pros unless things pick up a bit.


Only threat is 92L.
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1474. msphar
So is there any thing of interest weatherwise out to the East of the islands ? Looks to my inexpert eyes that things will be quiet for the next several days out in the MDR. This season will be hardpressed to meet the forecast of the season predictions made by the pros unless things pick up a bit.
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1473. boyzNme
Quoting LightningCharmer:
You're welcome.


I have never listened to NasaTV and I look forward to another attempt tomorrow night. Here's hoping it is nice & clear so we can see it from SFL!! Many thanks for the link and to Codaflow for the insight.
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1472. 7544
new cmc goes a little further west with 92l is the front due to stall out over cent fla
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Quoting boyzNme:
Shuttle launch just scrubbed due to weather. They are going to try again tomorrow. I don't understand all of their jargon, but they are going for "24, 0105". I guess they mean 24 hours from now. NasaTV will start broadcasting tomorrow nights launch at 830pm and they just confirmed that launch will be rescheduled to 1:10AM Wed. I don't know who gave the link for NasaTv, but thanks!
You're welcome. Someone else may have provided a link as well.

Blogger, Codaflow, works in the NASA pressroom at the Cape, and was providing good information.
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dang Shuttle launch scrubbed due to weather.i was looking forward to seeing it go up from my house,although it is only a red dot as i live way away from the Cape.
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1469. snotly
silly earthlings.
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1468. boyzNme
Shuttle launch just scrubbed due to weather. They are going to try again tomorrow. I don't understand all of their jargon, but they are going for "24, 0105". I guess they mean 24 hours from now. NasaTV will start broadcasting tomorrow nights launch at 830pm and they just confirmed that launch will be rescheduled to 1:10AM Wed. I don't know who gave the link for NasaTv, but thanks!
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01:10:22 EDT rescheduled launch time tomorrow.
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Launch scrubbed due to weather. Trying again tomorrow.
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1465. whitewabit (Mod)
Just scrubed the launch...
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Red on flight-precip, cumulus, anvil, etc. Scrub for today.
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Scrubbed. Thanks Bill.
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Green on ceilings and visabilities. Lightning from phase-two to phase-one.
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Weather should be clearing up 7 minutes prior to launch. Sounds as though they can't tell whether they lost some helium. Possible instrumentation problem?
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well looks like a scrub .. 24 hour turn around..an here we go again.....
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Quoting bingcrosby:
Weather seems to be improving slightly near the shuttle. Just a matter of timing.


Whoooeeee. This one is gonna be close. Very dynamic weather situation. I'm crossing my fingers.
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Weather seems to be improving slightly near the shuttle. Just a matter of timing.
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1457. JRRP
see you later...
Link
Member Since: August 16, 2007 Posts: 0 Comments: 6213
Launch trend is improving
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1455. KEEPEROFTHEGATE (Mod)
iam out as well later all
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1454. JLPR
well since not much is going on here
im going to bed too
lets see how 92L looks tomorrow =P
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HI all, I will be here to talk in about two hours. I am currently busy, but I would like to talk about the atlantic invest at around 1a.m. MST. Thanks, I had better not hog the comments.
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Quoting Coldwaterlover:
I think 93L has a better chance of becoming 93E or a storm on the other side if it can hold together over the mountains of South America.
pssst...don't look now, but thats Central America.
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I think 93L has a better chance of becoming 93E or a storm on the other side if it can hold together over the mountains of South America.
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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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