Outside of a beautiful day today, the panhandles will be in the grasp of a relatively active weather pattern over the next 7-10 days. We’ve got a chance to see thunderstorms, regular rain and some light snow showers between now and next Thursday.
Our first bout with thunderstorms will be in some of our southeastern counties tomorrow. The CAPE values are measuring between 200 J/kg and 700 J/kg. And bulk shear values are between 15kt to 30kt.
To the right is a look at CAPE values on Wedneasday afternoon. Notice the purple is basically area wide. This is an area with a CAPE value below 100 J/kg. But as we ge to brighter colors we increase the CAPE values to 1200 J/kg. Notice in the far southeastern counties of the Texas panhandle we will have cape values between 400 J/kg and 700 J/kg.
Now you might be asking: “Nick? capes? We aren’t talking about Superman…”
You’re right. CAPE is short for convective available potential energy. That is, we are looking at the potential energy available for a buoyant parcel of air. It is also known as instability.
What does that mean? Well… lets think about it like this.
The larger the CAPE value the more unstable the atmosphere is. If the atmosphere is unstable then there is more buoyant energy in a pocket of air. If a pocket of air has more energy to be more buoyant, it will rise faster. And remember that rising air is also known as an updraft.
So, if an updraft is rising faster, it allows for storms to build more quickly. It also allows for storms to hold larger hail and produce more damaging tornadoes.
A basic CAPE outline
- 0-1000 = Marginal Instability
- 1000 – 2500 = Moderate Instability
- 2500 – 3500 = High Instability
- 3500+ = Extreme Instability
Based on the above list, and the numbers coming back for Wednesday showing CAPE values between 200-700 J/kg, it looks to be just enough to build some “stronger” storms where there is available moisture.
Right now, I think the chances for ANY storms is between 5% and 10% so we aren’t looking at an imminent thunderstorm threat, but, should any storms develop, you can expect some moderate showers, some rumbles of thunder and maybe some very small
Keep in mind CAPE values aren’t the end-all-be-all for severe weather. But they are on of the contributing factors we look at when dissecting the atmosphere.