Interesting Visible Satellite Image

[Michael Riedl]

Hello. When looking at the Central Plains Vis Sat image this afternoon I noticed a strange feature along the KS/NE line. It looks as if it is a swirl in the upper levels of the atmosphere because it has clouds beneath it. When examining mesoanalysis it didn't appear as if there was an ULL there. So basically what I am asking is what is causing that?

 

[rdale]

Easier to notice if you animate... Looks like it started as the cirrus shield of a thunderstorm complex. Storms gone, upper-level clouds still here. I'd be shocked if something like that would show up in any analysis.

http://rammb.cira.colostate.edu/visit/sat_signatures.html

http://rammb.cira.colostate.edu/visit/topic_sat.html

 

[Jeff Miller]

Exactly what Rdale said.

Trying to figure out what a Satellite image is in this kind of instance without animating is trying to determine if a wall cloud is rotating by looking at a picture and not a video. When I saw the picture, this is actually the link that I pulled up:

http://www.rap.ucar.edu/weather/sat...small&endDate=20100527&endTime=-1&duration=12

You can clearly see the thunderstorm complex dissipating while upper level clouds remain and move SEward throughout the day. Always animate before you speculate.

 

[Stuart Robinson]

Tropical Depression over Nebraska

LOL looks like an young tropical depresion

 

[Mike Kovalchick]

Looks like a mesoscale convective vortice (MCV).

Per one of Tim's V. forecasting books..they are associated with a MCS and may outlast it as sort of a residual circulation. They are most likely to form in environments with weak shear but moderate to high instability. They sometimes act as a focal area for convective redevelopment.

 

[Mike Moore]

LOL... watch out for Jim Cantore.

 

[rdale]

I'm not sure, my concern is the lack of any low or mid level conditions changing makes me wonder about it being a "full-fledged" MCV. In any case, I forgot about this til I searched VISIT:

Mesoscale Convective Vortices
http://rammb.cira.colostate.edu/visit/mcv.html

A cursory look and I don't find this:

19. <!--[endif]-->One thing common to MCV environments: very unstable. LI<0, even in morning soundings (which explains the pre-Noon convection over Iowa on page 10). Normally, a mesolow at midlevels, and a meso-high at the surface, which high is associated with cooling. You can also have meso-lows at the surface. The pressure distribution is strongly affected by cloud microphysics. Surface heating also plays a role -- mesolow at surface much more likely if a boundary layer that is warmed.<o></o>

 

[Jason Berner]

It does look like an MCV to me from what I have seen. Basically, the latent heating of the condensing particles warms up the mid-upper atmosphere during long-lived MCS events. The long-lived nature means you get a pretty strong meso-low in the upper levels of the atmosphere which can outlast and the MCS itself and persist on with the synoptic pattern. These can help show spawn up storms and other signif. weather on down the line.

 

[rdale]

I'll repost my question since the other thread got merged in If it was a true MCV, why was there absolutely no reflection of it at the surface?

 

[Mike Smith]

I just ran a loop from yesterday ( www.rap.ucar.edu/weather/satellite/...=small&endDate=20100527&endTime=21&duration=7 ) and it broke off from a thunderstorm complex.

 

[Jim Saueressig]

I looked at that on cod yesterday on loop and thought it was interesting how tight the center was in the higher res.

 

[Mike Smith]

I looked at that on cod yesterday on loop and thought it was interesting how tight the center was in the higher res.

Yes, it is just amazing. Had there been a boundary there with enough instability there likely would have been some wicked rotating thunderstorms.

 

[Jason Berner]

I'll repost my question since the other thread got merged in If it was a true MCV, why was there absolutely no reflection of it at the surface?

Am I wrong when I say that the MCV is an mid to upper-level feature and, therefore, would not have related surface obs? I ask that more as a question because it is a pretty lightly touched upon idea in MCS after effects so I am not totally versed in their structure. But it makes sense that a mid-level feature would not have any hints of it at the surface.

I think this site gives a good case example.
http://cimss.ssec.wisc.edu/goes/misc/970708.html

If you look at the NOAA profiler image, you see the 4-8km winds switch from westerly flow (right side i.e. earliest time) to N and NE as the mcv flow passes over it. The sfc. winds to switch around but that is more due to the passing of the boundary than the MCV.
http://cimss.ssec.wisc.edu/goes/misc/lth_970708_profiler.GIF