So this is a quick post about yesterday’s forecast, and why storms didn’t fire up in DFW. We’ve seen posts across social media of individuals laughing with some memes about the lack of storms after the forecast, and we’ve seen some people also frustrated and upset with forecasters over the lack of storms. So what happened?
In short the answer is sinking air, and the “CAP” we speak of regularly. Above is an image of a “sounding” which is a sample of the atmosphere, collected by weather balloons. This data shows us conditions in the atmosphere we cannot see with surface weather stations or satellite. This Sounding was a special sounding at 2pm right before we had forecasted storms to develop.
The red line that is circled, was the “CAP” that was apparent on that 2pm sounding, suggesting it was still in place, it was weak, yet it was holding up.
What is the CAP? The cap is a layer of warm stable air that acts almost as a lid on a pot. It prevents warm air from rising in the atmosphere and colliding with cool dry air in the higher levels in the atmosphere.
We were monitoring conditions as the energy available, dew points, shear, and surface heating was very favorable for storms to develop. Conditions in place would have made storms go up rather quickly, these storms would have been able to easily break through parts of the CAP and cause some problems. So why didn’t these storms develop?
The answer is Sinking Air, as we mentioned earlier. In order for storms to develop, they need moisture. Sinking air yesterday, impacted the moisture storms needed to develop, killing storm updrafts, and limiting storm development.
What is sinking air? Sinking air is air that is compressed down, causing temperatures to rise at the surface, while also eliminating any warm moist air from rising. Sinking air is a common occurrence during the summer with our sunny days, when we have high pressure systems over the region.
So this was a quick explanation as to what happened yesterday. We wouldn’t call yesterday a bust, we would say we are very fortunate! These two factors prevented our area from seeing a potential significant severe weather event. The parameters yesterday were very supportive for storm development, and for all types of severe weather, including very large 2”-3” hail, as well as a few tornadoes, some could have been strong, as areas to our north in Oklahoma, and red river counties saw yesterday.
So for anyone who is upset with the forecasters and weather reporters yesterday for no storms after all of our forecasts, just know that we are very fortunate we didn’t see any storms fire up over the DFW area, and that these factors helped prevent this activity. We would rather a “busted forecast” be the outcome, than a damaging severe weather event that impacts people’s lives.