• After witnessing the continued decrease of involvement in the SpotterNetwork staff in serving SN members with troubleshooting issues recently, I have unilaterally decided to terminate the relationship between SpotterNetwork's support and Stormtrack. I have witnessed multiple users unable to receive support weeks after initiating help threads on the forum. I find this lack of response from SpotterNetwork officials disappointing and a failure to hold up their end of the agreement that was made years ago, before I took over management of this site. In my opinion, having Stormtrack users sit and wait for so long to receive help on SpotterNetwork issues on the Stormtrack forums reflects poorly not only on SpotterNetwork, but on Stormtrack and (by association) me as well. Since the issue has not been satisfactorily addressed, I no longer wish for the Stormtrack forum to be associated with SpotterNetwork.

    I apologize to those who continue to have issues with the service and continue to see their issues left unaddressed. Please understand that the connection between ST and SN was put in place long before I had any say over it. But now that I am the "captain of this ship," it is within my right (nay, duty) to make adjustments as I see necessary. Ending this relationship is such an adjustment.

    For those who continue to need help, I recommend navigating a web browswer to SpotterNetwork's About page, and seeking the individuals listed on that page for all further inquiries about SpotterNetwork.

    From this moment forward, the SpotterNetwork sub-forum has been hidden/deleted and there will be no assurance that any SpotterNetwork issues brought up in any of Stormtrack's other sub-forums will be addressed. Do not rely on Stormtrack for help with SpotterNetwork issues.

    Sincerely, Jeff D.

Jet Streak Quadrants

John Peters

EF3
Joined
Mar 2, 2007
Messages
202
Location
Ft. Collins, CO
Can anyone find a good write-up describing the dynamics behind jet streak entrance/exit regions and their relationship with ascent/descent (i would prefer a more mathematical explanation)? I'm fairly certain that this phenomena is due to a-geostrophic flow properties, and cannot be represented through QG theory (this is what I've been told at least).
 
Jeff Haby has a great section on jet stream dynamics here: http://www.theweatherprediction.com/charts/300/ In short, lift is enhanced in the right-rear and left-front quadrants.

22.jpg
 
Howie Bluestein covers it quite nicely in "Synoptic-Dynamic Meteorology in Midlatitudes" Vol 2 pages Ch. 2.8. The equations are good for a qualitative analysis but as usual with Dynamics it is hard to quantify variables without taking into consideration approximation error. He uses QG analysis in one and SG in another. I consider both volumes good to have in a book collection for referencing.
 
If we divide a jet streak in half width wise, we can see two circulations. A thermally direct circulation (warm air rises, cool air sinks) in the entrance region, and a thermally indirect circulation (cool air forced upward, warm air sinks) in the exit region. The places where rising air is occurring are the right entrance and left exit quadrants. This is where the upper level divergence is enhanced. Where the air is sinking in the left entrance and right exit quadrants, upper level convergence is maximized.

Boy I love advanced synoptic meteorology. I can actually attempt to explain some of this stuff.
 
Thanks for the input guys. I guess one could numerically plot a velocity field based on the raw momentum equations and then use finite differences to identify areas of upper level convergence or divergence. Is there a method of manipulating say the QG omega and height tendency equations in order to quasi-quantitatively analyze the vertical motion field? (i guess i consider QG analysis quasi-quantitative)
 
Chris Nuttall said:
For more info, there's a MetEd module titled "Jet Streak Circulations" that is a very good presentation on this exact subject.
Click to expand...

I highly suggest it to any interested party! It's a great overview of jet streak dynamics... The exact link is http://www.meted.ucar.edu/norlat/jetstreaks/ ... You may need to register if you haven't already, but it only takes a minute to register. Again, highly suggested, even for those who don't care about the math of it.
 
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