Monday, 20 February 2012
Conditions will be coming together late this afternoon and early this evening to produce low topped supercells across central/eastern Oklahoma and southern Kansas. This might come as a surprise to some people considering today’s date. But enough cold air at the mid levels and a marginal amount of low level moisture will come together to bring conditions favorable for a couple tornadoes.
The main limiting factor truly is the surface dewpoints, which will struggle to reach the lower 50s by the early evening hours across central Oklahoma. This will limit overall instability as CAPE will likely only be in the 200-500j/kg range. While this is sufficient for severe storms and even supercells, it suggests short lived low level mesocyclones, i.e. brief tornadoes as storms fight for low level CAPE.
From a storm chasing perspective these storms should be moving to the northeast very quickly in the neighborhood of 50mph! That wouldn’t usually be a huge problem, but terrain and finding a decent road network will quickly become a big issue shortly after storm initiation.
According to the latest hourly RUC guidance in addition to the 4km WRF, storms will initiate around 4-5pm local time near the I-35 corridor and quickly race northeast into the sticks of east-central Oklahoma. Depending upon exactly where you are in the state east of I-35, you may or may not have a good road network or good terrain.
If enough moisture can surge into the OK/KS border, that may a good play for today based on terrain. I would normally say that playing the northern target would be a pretty big gamble on a day like this with such limited low level moisture. But mid level temperatures will be so cold (-25 to -30C) that it might not matter as much today. A tornado could touch down anywhere from central/east central OK to south central Kansas.
But in the end it’s late February and anyone with the ability to chase a low topped supercell in Oklahoma/Kansas with the potential to drop a brief tornado should take advantage of it.