04/25/04 NOW: NM TX OK

[Larry J. Kosch]

Someone in today's FCST thread requested a NOW thread since a severe thunderstorm watch has been posted for this area and several STWs have been issued. Post your NOW reports here. LJK.

 

[Stuart Robinson]

Indeed some storms have fired over the Childress / SW OK area. Looking at the dew point depression these have to be elevated but I do note that some cells have MESO sigs.

 

[Jeff Snyder]

Originally posted by Stuart Robinson
Indeed some storms have fired over the Childress / SW OK area. Looking at the dew point depression these have to be elevated but I do note that some cells have MESO sigs.

Just a little terminology note, since I've seen/read this several times lately. Most of the time, when the term "elevated" is used to describe a storm, it is used to describe the updraft source region. In this case, elevated refers to the updraft source region being above the surface. This is as opposed to "surface-based" (of course, meaning the originating updraft parcel level is at the surface). Elevated thunderstorms typically occur when there is elevated instability, yet the atmosphere is capped to a surface-based parcel, which is quite common north of warm fronts or at night, as nocturnal cooling increase capping relative to a surface parcel. Whatever the case, "elevated" convection has little to do with dewpoint depression, as long as the surface is the source of the updraft.

You, if I'm not mistaken, are meaning to say that the storms are high-based, meaning that, because of large dewpoint depression, the actual cloud base (LCL) is quite a ways up. However, these storms can still be (are likely are) surface-based (and thus not elevated) because the surface air is the source of the updraft. Just wanted to point out a slight ambiguity that I've been reading...

 

[Stuart Robinson]

Thanks Jeff,

you are correct - I did mean high based