Holiday Heat Prevails, Storm Chances Remain
Forgive us for the number of times we say, “hot as a firecracker” in the coming days, but it certainly will be a true sentiment for the week ahead. A large heat dome is re-establishing itself over the central U.S., larger than ever this summer. The building heat combined with lots of residual moisture in our air means several days of dangerous heat index values lie ahead.
The aforementioned heat dome, shown above, is ruling our conditions this week. The highest temperatures likely occur Tuesday before a very gradual cooling trend. However, each day will feel awfully similar to the next. This ridge is sliding westward with time. As that occurs, an easterly wind develops, bringing in some slow-moving upper-level waves of energy. The first could impact your Fourth of July plans.
It will be like most other Fourths with hazy, hot and humid (the summer H trifecta) conditions. The one kink in the forecast will be a wave of energy sliding westward that could spark a few thundershowers during the day. The bulk of the activity will be to the south near the ArkalTex and into Texas. However, it’s likely to be spotty and affect maybe 10% of the viewing area. Just don’t be totally surprised if a downpour briefly interrupts your holiday pool-time or BBQ. By that evening, all firework displays should easily be a “go.”
Later in the week, additional pieces of energy slide our way. This is a very typical mid-summer pattern for the Deep South with scattered thunderstorms firing up with daily heating. Given the position of the “heat dome” by the weekend, Green Country will also share that pattern. Just about any day could offer you brief relief with a thundershower. With very weak steering winds, storms will dump most of their rain in a very small area so beneficial rainfall will only fall in pockets. The added cloud cover will take the edge off the heat late in the week and bring our readings back to near normal with highs in the lower 90s. Still, count on a heat index of at least 100° each afternoon. Below is that heat index trend into the weekend.
The longer range pattern continues to support above normal heat. It is becoming increasingly clear this will be a hotter than normal summer. Given our humidity, however, reaching 100° is more of a challenge. Until we lose more of this atmospheric moisture (have a drier wind from the southwest or west), we won’t be adding much to our triple-digit days in 2018… of which we have seen none so far. The general weather pattern this month though supports very few organized storm systems making it to Oklahoma as well. This drier than normal expectancy might also act to lower our humidity and raise our daily temperatures with time.