Tis the Season!
Hurricanes (How they form and the curve balls they throw)
The peak month for these self-sustaining heat engines is September closely flanked by August and October. With its name derived from ‘Hurrican’-the Carib god of evil-this cyclonic twisting Goliath requires a combination of conditions to rear its ugly head.
Sea surface temperatures must be at least 27 degrees Celsius and they tend to form five to eight degrees north and south of the equator for rotation to begin from the influence of the Coriolis force. (Remember that phenomenon that causes everything in the Northern Hemisphere to be deflected to the right but has zero effect at the equator?). As well, a warm core of air is needed. What mixes all these ingredients together is a weak weather disturbance, a tropical wave, moving westward from the area of Cape Verde, Africa. This atmospheric support acts as an impetus for thunderstorm formation grouping this newborn storm into a self-perpetual heat engine as latent (hidden) heat is released from the process of condensation, causing more vertical development.
Hurricanes are born as a tropical depression with winds less than 34 knots. The next stage, the tropical storm, sustained winds of 35 to 64 knots occurs and is when the storm is christened with an official name. Today, names alternate between the male and female gender and are predetermined for five years, after that the names are repeated. Some names are retired because of their destructive past. Andrew in 1992 was one of them. By definition, a tropical storm becomes a hurricane when winds exceed 64 knots. (A Hurricane is known as a Typhoon in the Pacific Ocean, Cyclone in the Indian Ocean and a Willy-Willy in Australia).
The most significant clouds are the cumulonimbus (thunderstorm cloud) topping at a whopping 50,000 to 60,000 feet. Reported winds can get as high as 130 to 150 knots, after that wind measuring devices (anemometers) are destroyed. Engineers estimate from structural damage that winds of 170 to 200 knots could occur. Winds drop off quickly to less than 15 knots in the ‘eye’. The diameter of the ‘eye’ is approximately 6 to 25 miles (11 to 45 kms) and in this region there is usually no precipitation and most clouds clear away. The reason for the ‘eye’ is because of subsidence. The air at the center sinks causing warming due to compression, thus a break up of clouds. Temperatures at the core tend to be five degrees warmer as a result. Just to give some indication as to the intensity of these storms, a small hurricane will drop over a period of 24 hours, 20 billion tons of water. They are equivalent in energy to 500,000 Hiroshima size atomic bombs averaging six atomic bombs per second. Typical wave heights get up to 35-40 feet (11-13 meters) although the very intense hurricanes achieve heights of 45-50 feet (15-16 meters) with unconfirmed heights of 60 to 90 feet (20-29 meters).
Typically hurricanes move westward at speeds of 8 to 16 knots and then begin to curve northward. As they track northward they will show signs of fading as colder waters prevail. As well, when they track over land, surface friction tends to take the ‘wind out of their sails.’
However, now and again Mother Nature throws a curve ball, and this is what happened in late October 1991. Hurricane Grace on October 27 moved northward and became extratropical. Extratropical means ‘beyond or outside the area of the tropics.’ Not to be confused with extra, ‘over and above what is normal.’ It was a combination of extenuating circumstances that caused a rebirth of a massive destructive monster, which the National Weather Service described as ‘the perfect storm’. From a weak low-pressure system sitting off Nova Scotia, combining with a cold intrusion of air from the continent and the moisture from Grace, this resultant storm caused millions of dollars of damage along the eastern seaboard. Also dubbed the ‘Halloween Storm,’ it sank a sword-fishing vessel; the Andrea Gail with all hands on board perishing. It became the basis for Sebastian Junger’s novel, The Perfect Storm, and now the movie. Mother Nature threw yet another curve ball because the storm found a warm water source from the Gulf Stream sending it back into Hurricane status. The Halloween storm or ‘Perfect Storm’ was then known as the ‘Unknown Hurricane.’ A decision was made not to give it a name, because the media’s attention was still focused on the enormous damage and thus it was felt it could cause major confusion. The ‘Unnamed Hurricane’ brought a bizarre ending to one of the most massive Atlantic storms on record.
This redevelopment of hurricanes also happened in October, 1954. Hurricane Hazel first struck the Carolinas as a category four. (There are five categories with ‘five’ the most intense packing winds of 135 knots or greater). She merged with a low-pressure center to become a colossal extratropical storm that devastated Toronto, causing 76 deaths.
We have come a long way in forecasting their movement and understanding the complexity of these one eye monsters, and yet only Mother Nature herself knows where the curve balls she throws will land.
Doug Morris is an Air Canada pilot and has worked at the Canadian Hurricane Center in Halifax as a meteorologist.
Tired of your job? What about working on weather reconnaissance flights that fly into the eyes of hurricanes in the name of science and research? Known as Hurricane Hunters, NOAA (National Oceanic and Atmospheric Association) flies two P-3 Orions and the American air force reserve uses C-130 Hercules all laden with meteorological instruments compiling specifics of a storm and data for research.
*************** NEW *********************
Here's the TAF for CYHZ. They have the winds up to 40 knots but straight down runway (14) ....for now. Yeah baby!
BECMG 0316/0318 20012KT
FM040300 20005KT P6SM SCT120 BKN200
BECMG 0404/0406 16012KT OVC006
FM040600 16012KT P6SM OVC006
BECMG 0408/0410 14020G30KT
FM041000 14020G40KT 1SM RA BR OVC003
RMK NXT FCST BY 031800Z=
How close to a Hurricane like Earl, do airliners fly?
We won't fly into the thunderstorms of course, but the big issue is the surface winds. And a few days ago, Halifax had a runway shut down.
There's also taxiing issues with things blowing across the ramp. Once I saw a baggage container blow by. As well the cargo doors have wind limits
on them. Also there are potential power outages. Lots to think about when a hurricane pays a visit.
Getting ready for an Edmonton turn.
Hey Captain Doug,
I have been reading your blog since I discovered it in yearly April!! I love reading about your adventures and hope to be an Air Canada Pilot some day!!!
Hope to see you on a flight someday!
Hi Adam. If you have a dream, then it will happen!
I'm off to Edmonton, Alberta and back.
Keeping my distance from Earl! :)
Keep in touch!
How badly will Earl effect ops. in CYHZ and the maritime's?
With the Airbuses and Embraer's being most of Air Canada's short haul operations, it should surely be an interesting day or two at dispatch.
Eh, bring it on! Want to see something cool? How about the track of the G4 that NOAA has to fly into it.... http://flightaware.com/live/flight/NOAA49/history/20100902/0617Z/ZZZZ/KTPA . I am surprised its going to downgrade to a CAT 1. First day back for us and it was so warm so everyone left and we went down to the lake to swim, felt like 40+ . Tomorrow after school like 20 of us are gonna go down to Rainbow Haven beach and swim, should be neat to see how high the ways are.
My dad isn't that lucky :P He has to go back to work on Sunday to deal with the mess that the hurricane left him :D I am pretty sure he told me though that Air Canada is going to try and ferry the planes out somewhere before it hits. I know that's what they did for Juan and White Juan.
Or, I guess now it seems like the idea to cancel most or ALL of the YHZ flights for Saturday has passed through the minds of high up company. Beats flying them in and wasting fuel out.
Hi Captain Cameron!
Seems like there has been confusion with this term for years.
Here's what someone wrote on the net confirming your definition.
A "willy willy" is the Aboriginal name for a kind of a mini-tornado, like you'll be driving across the Outback and there'll be a whirling column of dust in the distance. ("Willy" means wind, and repeating a word twice means "bigger or more of."
However, here lies the confusion.
Here is confusion in the definition of a willy-willy. In the United States, the National Weather Service defines a willy-willy as “a tropical cyclone of hurricane strength near Australia”. But the Australian Bureau of Meteorology defines the term to mean a dust devil where “local hot spots can develop on the ground, drawing in cooler air from around them and causing spiraling of the air”. The American Meteorological Society also agrees on the newer definition of a willy-willy. While the term was previously used to denote a tropical cyclone, it is now commonly used in reference to dust devils.
To add even more confusion many Americans call a tornado a cyclone.
And they are by the true sense of the definition correct!
Cyclone: a system of winds rotating inward to an area of low atmospheric pressure, with a counterclockwise (northern hemisphere) or clockwise (southern hemisphere) circulation; a depression.
• another term for tropical storm
So I'll blame all this on the Coriolis effect. You guys veer to the left and we veer to the right. :)
No, I'm not going to say it's a boeing/Airbus thing.:)
Cameron. Thanks a million for sending your comments.
Can I ask who you fly for?
Daniel. I just checked the TAF (aviation forecast) and for Saturday morning the winds will be from the southeast at 30 knots. Right down runway 14.
Unfortunately, the TAF does not go further than 1200z. Stay tuned. I'm glad i'm heading the other way today. San Diego!
Anon. (Nehal). I see Environment Canada is knocking the wind out of Earl's sails by forecasting a Tropical Storm instead of a hurricane.
Don't get me wrong it will blow up to 50 knots and rain "cats and dogs" but it looks like this guy is losing his stamina.
He will arrive in Nova Scotia (Yarmouth, southwest portion) at 1200z and will be in P.E.I by 1800z. There will be a few hours of high winds
and heavy wind so things will snarl up for awhile. Nothing insurmountable unless Earl decides to wreak havoc with the hydro.
I'll be watching this transpire while I'm inbound from San Diego.
Just got back from the beach and wow, the waves have to be 20 feet. Me and my friend were just surfing the ways and stopped for a little to talk and then she realized that were drifted at least 50 feet. It was hard because if you tried to surf the waves back in, you would get like 5 feet and then get pulled back so we had to swim hard... It was a good sunset, to bad things are about to destroyed... O well, we'll see how things run tomorrow .
Bring it on Earl!!! :P
Daniel. Presently in San Diego. I looked at the latest aviation forecast and it's forecast to gust to 50 knots for six hours at YHZ. Talking to an F/O in Toronto flight planning and he was heading your way. Better him than I. I'd rather look at the Palm trees in SAN than watching trees be uprooted in N.S.
Enjoy the ride...and be careful with those waves!
KZBW BOSTON UPPER FIR
KZBW WS 040255 040455 3E#SIGE. MKCE WST 040255. CONVECTIVE SIGMET 3E. VALID UNTIL 0455Z. ME MA NH RI CT NY AND ME NH MA RI NY CT NJ DE CSTL WTRS. FROM 50N ENE-120SE
BGR-190SE ACK-170SE SIE-30N JFK-50N ENE. AREA SEV
EMBD TS MOV FROM 21020KT. TOPS ABV FL450. WIND GUSTS TO 75KT POSS. TS ASSOC WITH HURCN EARL.=
CZQM MONCTON FIR
CZQM WS 040255 040455 3E#SIGE. MKCE WST 040255. CONVECTIVE SIGMET
3E. VALID UNTIL 0455Z. ME MA NH RI CT NY AND ME NH MA RI NY CT NJ DE CSTL WTRS. FROM 50N ENE-120SE BGR-190SE ACK-170SE SIE-30N JFK-50N ENE. AREA SEV
EMBD TS MOV FROM 21020KT. TOPS ABV FL450. WIND GUSTS TO 75KT POSS. TS ASSOC WITH HURCN EARL.=
Boston Center has been re-routing a few aircraft but it seems now its up to the pilots to request it if they see something on the WX radar. Usually just deviations of 30 - 20 degrees.
Daniel. Stay safe! I'm glad my routing took me west instead of east. Doug
Yeap, will do. I will send you pictures tomorrow if I see something, say like my BBQ taking flight off my deck or a tree going flying. lol
Wow.. ACA861 is actually trying to land on 14 with vinds gusting 65 knots. They have balls to do that.
Ok , nevermind. He went around at around 800 feet.
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