Oklahoma’s Weather Forecast Signals Potential For Severe Storms

Professional weather analysts and meteorologists have already begun warning folks in Oklahoma about the sketchy weather forecasted for this weekend starting Friday, May 16. There are several factors that affect just how the weather pans out, but one topic keeps coming up.

If you're not from Oklahoma, or other areas of the United States that see a lot of tornadic activity, you might not understand why having a "cap" during storm season is so important. Even seasoned Oklahomans who have lived here their entire lives couldn't tell you what the cap is or how it affects our storms.

With the help from other weather professionals, we'll help you understand the cap, how it influences our forecasts and what happens when it breaks. "No cap" - it's more important than you may realize.

What is the 'cap?'

In the WeatherLink LLC Facebook group, Storm chaser Mark Slavin explained what meteorologists mean when they refer to the "cap."

"The cap is a warm layer of air a few thousand feet above the surface," he said. "Storms need hot air at the surface and cold air aloft to develop."

If the layer of warm air is strong enough, it keeps the updraft from rising and storms from developing. If the cap breaks, meaning it's not hot enough to keep the updraft from rising, that's when severe weather breaks out.

Compare the storm and cap to a soda bottle, explained by meteorologist Shelby Mac with WKRN. The liquid within the soda bottle represents the storm: with all of the right ingredients, all you have to do is shake it up and it's ready to explode.

The soda bottle cap is similar to a storm cap - it stops the explosion from happening; that is - unless it breaks.

Weekend forecast for Oklahoma looking hot, windy and potentially severe.

Forecasters are anticipating all of the ingredients for severe weather to be present this weekend.

Saturday, May 17, storms could produce "damaging hail, high winds and isolated tornadoes," according to Meteorogist David Payne. The current percentages for storms aren't high, with only 30% - 40% chances across the state.

Meteorologist Mike Morgan has a similar outlook for storms, although his forecast involving instability and wind shear predicts a higher risk for severe weather in the majority of western Oklahoma.

"Doesn't guarantee there's going to be storms, the cap has to break. But the cap should break, especially in this red shaded area that I show you here," he said.

Sunday, May 18, things are looking a little more intense with a higher chance for instability, according to Morgan. Areas for higher instability include "up and down I-35, Highway 81, backed more into western Oklahoma... lot of instability, a lot of wind shear."

Meteorologist Lacey Swope also has storms forecasted for parts of Sunday. Things should stay relatively quiet during the day, but storms should develop Sunday afternoon into overnight per her forecast.

"Oklahoma could see numerous rotating storms Sunday afternoon and evening with a threat for wind, hail and a tornado threat," she said.

One of the most important things to keep in mind is the cap; severe weather could stay at bay as long as the cap stays in place.

What does the cap look like and how do we know when it breaks?

Some radars can show surface-based data, indicating where the cap is on a map and how strong it is in an area. Weather analyst Max Velocity used this tool to show viewers an example from 2022, indicating where the cap was present and weakening over time.

"Sometimes it's accurate, most of the time it's pretty close to accurate, but obviously it's not always accurate," he said.

When the cap breaks, that's when dangerous storms develop and intensify. Many of the deadliest tornadoes in Oklahoma's history happened when the cap broke. Take a look below at the deadliest ones that have hit the sooner state.