Atmospherics Crash Course!

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Vertigo
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Atmospherics Crash Course!

Unread post by Vertigo »

My other thread got moved to the archives :/

So im intending this thread to be for people to ask questions about atmospherics, in order for us all to better understand the dynamics going on above our heads.

Ill get the ball rolling.

In a skew-t diagram, what does it mean if the environmental reading crosses over the dewpoint reading? What conditions might it produce?
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Willoughby
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Re: Atmospherics Crash Course!

Unread post by Willoughby »

Hi Vertigo,
They will never cross over as you can't achieve 101% humidity... the dewpoint and temperature lines can well join which means 100% humidity.

12Z NZWP sounding:
Image

You can see it's a very moist environment and rain is likely... low clouds forming at around 900mb, then the layer of altostratus from 850mb with the inversions and joining dewpoints. :)
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Vertigo
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Re: Atmospherics Crash Course!

Unread post by Vertigo »

and its my understanding that the moist adiabat line needs to be on the right hand side of the ambient temp line for thunderstorm potential to develop?

thanks for that, makes sense!
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Re: Atmospherics Crash Course!

Unread post by NZstorm »

its my understanding that the moist adiabat line needs to be on the right hand side of the ambient temp line for thunderstorm potential to develop?
Yes. The skill with skew-t is knowing what parcel to lift (temp/dewpoint) and anticipating upper air environmental changes.

In NZ sounding observations are taken at relatively stable times of the day 11am (00Z) and 11pm (12Z).
I don't know what the 09Z refers to on the Wyoming site unless it is a forecast sounding.
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Re: Atmospherics Crash Course!

Unread post by arthurhh »

I don't know what the 09Z refers to on the Wyoming site unless it is a forecast sounding.
0900 Zulu would be my guess, or to those who speak English 9am
http://tokoroaweatherlive.net
Tokoroa's Live Weather
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Vertigo
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Re: Atmospherics Crash Course!

Unread post by Vertigo »

big convection in auckland today. the whenuapai sounding shows a shallow but positive cape, a distinct and fairly weak cap, and good shear. am i right in predicting that these are good conditions for rain, at least?

http://www.bom.gov.au/fwo/reg/IDS65024/ ... .93112.png

edit: nm, it just updated!
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