Welcome New Members! We want to hear from you. Register, stop lurking and start posting!

Upper level trough

Archived Nerdy Forum (Weather Q&A).
Locked
P
Pete
Cumulonimbus
Reactions:
Posts: 470
Joined: Mon May 30, 2011 9:02 pm
Location: Albany, Western Australia

Upper level trough

Post by Pete »

Hey guys. How can I tell when an upper level trough is present. Can I do this by looking at the shear charts?
http://forecasts.bsch.au.com/stormcast. ... #stormcast" onclick="window.open(this.href);return false;
Cheers.
J
Jake Smethurst
Supercell
Reactions:
Posts: 3583
Joined: Mon Nov 23, 2009 8:49 pm
Location: Cheltenham

Re: Upper level trough

Post by Jake Smethurst »

Hi Pete, hows things.

Here is a post from Ken, a valued member that has just answered this question:
There's many out there but a couple include the Stormcast maps on the BSCH site (http://forecasts.bsch.au.com/stormcast.html" onclick="window.open(this.href);return false;) - mid/upper troughs typically show up on the upper wind charts (the "Shear" charts between around 700 and 300hpa... although they're actually only show the winds at those heights rather than true shear within a layer of atmosphere) like they do on surface wind charts.
Another one is the map viewer based on the ACCESS model at:
http://www.bom.gov.au/australia/charts/ ... u&model=CG" onclick="window.open(this.href);return false; - again, the same principle as above applies. Mid level cold air shows up on the 700 and 500hpa temperature charts on both sites while jetstreams can be identified on the 300hpa wind charts as ribbons and streaks of strong winds. Severe thunderstorms often occur under the left entrance and right exit regions of jet streaks provided there's also enough moisture and instability.
.

Hope that helps, any more questions, post away, I might be able to help too.
Jake - Senior AWF Forecaster
Feel free to send me a private message if you have any questions.
Locked