Sunday, June 6, 2010

MCS development in CO-NM

An MCS developed tonight in CO-NM in an impressively warm environment aloft.

At first glance, it appears upslope flow penetrated deep into CO and Northern NM, underneath westerly flow. The terrain served to initiate convection. The upslope flow was responsible for transporting some moisture approaching 50 F to the region.

The impressively warm atmosphere apparently did not stop convection along the NM-AZ border either. As with a previous study (Bunkers et al. 2010), this highlights that warm temperatures aloft do not necessarily reflect convective inhibition. The low level moisture, lapse rate aloft, and forcing are important. So why the reliance on these warm temperatures? Forecasters rule of thumb, that when the mid level temps get warm, convection becomes increasingly unlikely. Most likely this "rule" was the recognition of a process of warming by subsidence such that a cap was present and forcing was either weak or non-existent.

So, now that my script is done running here are some stats at 500 hPa:
STATION   T    T90
ABQ       -4C    -6C
DDC       -4C    -6C
LBF        -5C    -7C
MAF       -3C    -5C
AMA      -4C    -6C
top          -7C    -7C
oun         -3C    -6C
fwd         -4C    -5C
epz          -4C    -5C
oax          -6C    -7C
drt           -4C     -4C
crp           -4C    -4 C
bro           -6C    -4C
dnr           -7C    -7C
sgf           -5C    -6C
lzk           -4C    -6C

These are the ones I have checked and all but 1, have exceeded the 90th percentile. It would be interesting to see how often all these stations have simultaneously hit the 90th percentile of warm Temperatures.