Learning Weather - Part One - Understanding Models.

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stephenprudence
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Re: Learning Weather - Part One - Understanding Models.

Post by stephenprudence » Sat Nov 19, 2011 9:21 pm

Andy P wrote:Something i would like to ask on this subject -- And bear with me cos i`m a bit dumb when it comes to meteorology and it`s a difficult question for me to get across.
From what i understand, all the earth`s weather systems ( in the Northern hemisphere) move from West to East. The Gulf stream for example moves warm waters from the Caribbean -West to East. Whenever i`ve travelled East to Asia in an aeroplane- the flight there is a lot shorter than when you travel back. Due to the very fast and strong winds of the Jet stream that flow from West to East.And likewise, if i flew to the USA, the flight there takes longer than the flight back, Fighting against these winds. So why is it ( if the winds and tidal flows move so strongly from West to East in the Northern Hemisphere) do we sometimes get weeks of freezing weather - apparently from Siberia.
Siberia is thousands of miles East from the UK ,so how can their weather ever reach here considering the strong West to East jet streams,tidal flows and the huge distance between us?
The jetstream is the transporter of west-east airflows. Outside of the area there is very little stopping any other air flow occurring. When the jetstream is over you, you will have semi-permanent westerly flow over you.

However high pressure can deflect this jet stream flow, and during that time, easterly winds can easily gather momentum. The Coriolis effect (west to east) and pattern systems do not come into conflict with each other so easterly winds do occur.

The Gulf stream probably has water moving to the NE because of the shape of land around the Gulf of Mexico, but the transporter system for the Gulf stream is the North Atlantic Drift, which is the ocean current transport system.

Jet planes often fly within the jetstream, so going east to west it can be slower work battling against 200mph winds, whilst going with the jet stream will drastically reduce time.
Heswall, Wirral, UK
USDA equivalent average temperature zone: 9a/RHS zone 3
AHS Heat Zone: 1
Last 5 winter minimums:
2007: -0.1C, 2008: -4.2C, 2009: -5.7C, 2010: -10.5 (record), 2011: -4.9C, 2012: -5.3, 2013: -4.5C (so far)


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stephenprudence
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Re: Learning Weather - Part One - Understanding Models.

Post by stephenprudence » Sat Nov 19, 2011 9:43 pm

Darren:

First one: Worst case scenario - aka last year
Attachments
worst case scen..jpg
Heswall, Wirral, UK
USDA equivalent average temperature zone: 9a/RHS zone 3
AHS Heat Zone: 1
Last 5 winter minimums:
2007: -0.1C, 2008: -4.2C, 2009: -5.7C, 2010: -10.5 (record), 2011: -4.9C, 2012: -5.3, 2013: -4.5C (so far)


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stephenprudence
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Re: Learning Weather - Part One - Understanding Models.

Post by stephenprudence » Sat Nov 19, 2011 9:57 pm

Best case scenario.
Attachments
Best case scenario.jpg
Heswall, Wirral, UK
USDA equivalent average temperature zone: 9a/RHS zone 3
AHS Heat Zone: 1
Last 5 winter minimums:
2007: -0.1C, 2008: -4.2C, 2009: -5.7C, 2010: -10.5 (record), 2011: -4.9C, 2012: -5.3, 2013: -4.5C (so far)


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redsquirrel
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Re: Learning Weather - Part One - Understanding Models.

Post by redsquirrel » Sun Nov 20, 2011 6:01 am

thanks mate icon_thumright
i will save those two,it helps so i can see what could be getting better or worse icon_thumleft
mars ROVER broken down. headgasket faillure


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redsquirrel
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Re: Learning Weather - Part One - Understanding Models.

Post by redsquirrel » Wed Nov 23, 2011 7:48 am

i just looked at the models Steve,the 7th 8th and 9th pics almost have that big high you describe in the best case scenario.looking at these,am i thinking along the right lines?
mars ROVER broken down. headgasket faillure


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stephenprudence
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Re: Learning Weather - Part One - Understanding Models.

Post by stephenprudence » Wed Nov 23, 2011 10:30 am

Yes the models show something broadly resembling the best case scenario. It's very general of course, the best case scenario would be deep southwesterlies, so what is showing on the models are not the best case scenario, but they are favourable. icon_thumright
Heswall, Wirral, UK
USDA equivalent average temperature zone: 9a/RHS zone 3
AHS Heat Zone: 1
Last 5 winter minimums:
2007: -0.1C, 2008: -4.2C, 2009: -5.7C, 2010: -10.5 (record), 2011: -4.9C, 2012: -5.3, 2013: -4.5C (so far)


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redsquirrel
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Re: Learning Weather - Part One - Understanding Models.

Post by redsquirrel » Wed Nov 23, 2011 11:19 pm

icon_thumleft icon_thumleft icon_thumleft
mars ROVER broken down. headgasket faillure


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redsquirrel
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Re: Learning Weather - Part One - Understanding Models.

Post by redsquirrel » Fri May 25, 2012 6:34 am

am i reading them right at the moment Steve? it would appear there is too much high pressure around us at present to allow any highs from the north, north east to push in?
mars ROVER broken down. headgasket faillure


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