Brett Adair
EF5
BMX has stated that we have a cap....I am not seeing this on the BUFKIT soundings from the latest RUC models. Can anyone show me how to read the cap on the sounding itself instead of this numerical crap?
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1/2/06 Bust: Capping Inversion Question...
- Thread starter Brett Adair
- Start date
nickgrillo
EF5
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Jeff Snyder
EF5
The RUC forecast soundings I just looked at don't show much of a cap (with CINH in the -20 to -30 range) near BMX, which fits well with the SPC Mesonalysis (though that's based on the RUC as well). Another RUC run (w/ TAMDAR data) indicates a moist-adiabatic layer from the sfc to about 800mb... So, as long as the theta-e at the sfc is lower than the theta-e of that layer, you'll have a CINH profile that's pretty deep yet skinny. That said, I'm not sure good these RUC soundings are... The lowest 50-75mb is pretty saturated in the RUC forecast soundings, yet this isn't likely given full sunshine and southwesterly flow at the sfc. If anything, this would yield a cap that would likely be less than the rUC is analyzing (which is not much).
EDIT: For clarification, there doesn't need to be an inversion (temps warm with height) when you have a Tparcel < Tenvironment (CINH layer). For example, if the parcel is saturated, but a layer of the atmosphere has lapse rates weaker than 6C/km, the saturated parcel will cool quicker than the environment... You can end up with a layer with CINH that isn't an actual inversion, which is pretty common.
nickgrillo
EF5
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Brett Adair
EF5
Well, this profiles shows a little bit of a cap. The RUC data from ANB is also showing that the CINH and cap should have been broken given only a lower level CINH of 36J/kg from about 925-950mb.
Jeff Snyder
EF5
Brett,
That sounding doesn't show much of a cap for a mixed parcel (which the yellow trace indicates). If you take a surface parcel, you'll see that there is much higher CINH. In this particular case, the storm may not ingest exact surface parcel, but rather parcels a little above the surface layer.Mike Peregrine
EF5
Brett - well I thought you were capped fairly strongly, but after reading Jeff's posts above I'm suddenly unsure of myself ... go figure.
Wasn't sure what part of Alabama you are in exactly, so I pulled up Huntsville at http://www.wxcaster.com/rucskewts.php3?STATIONID=72228 and ran the 0z RUC. Go up to the 700mb (10,000ft) level and your temp line is almost the same as your surface temp, looks like ... (almost 20 degrees Celsius, if I'm reading this right) ... that's pretty dang warm for this time of year ... this time of year you'd ideally like to see the cap temp no more than 4-5 degrees.
Brett Adair
EF5
I see that....the RUC indicates a 900mb lapse rate of 8.4 but rates of 4.6/850 and 3.4/800.
Jeff Snyder
EF5
Mike, I just used the BMX sounding valid 20-21z as obtained at http://www-frd.fsl.noaa.gov/mab/soundings/java/ ... The sounding you showed does show significant CINH/capping.
EDIT: I wouldn't put too much stock in model forecast soundings, either. Many oddities may pop up depending on the model used to derive the sounding, including the type of convective parameterization used.
Brett Adair
EF5
I am 20 miles due east of EET in SRN Talladega County. The 15z RUC indicates that only a 2-3C 700mb temp.....I'm still not understanding why convection didn't fire.
Brett Adair
EF5
http://www.fileh.com/BamaStormChaser/BUFKIT.JPG
There is the BUFKIT I am looking at from BMX. Can anyone tell me what is wrong with that. I know the flow is more out of the SW now, but just give me some idea please. SKEW-T plots are not my specialty yet...Mike Peregrine
EF5
Well - just looking at it from my amateur perspective, I don't see anything really wrong with that setup. Guess you'll have to chalk it up to another unknown fly in the ointment ... I'm sure there's a good explanation, but then there are plenty of days we think things should happen but never manage to for one reason or another. Sorry Brett!
Brett Adair
EF5
Me either....hell, I'm just glad I didn't go to GA for an MCS. I would rather be sitting with one of my friends that is in KY right now with supercells breaking out ahead of the line.Tyler_Costantini
EF2
Another Amateur...
I don't know all hope has been lost. The Cold Front is still out their somewhere. VIS Sat images show alot of sun and surface data shows 81deg 59 dew point in central AL.
I have been out in the plains one many ocations everything 100% and NOTHING..
Brett Adair
EF5
I found it....I was reading wrong....the RUC indicates that there has been a level between 860-900mb of CINH of 160-200J/kg. That is pretty stout.Similar threads
