Why Does the Weather Always Change the Last Week of the State Fair?

People often observe that there's a significant weather change around the last week of the State Fair of Texas. (Sure, Big Tex has some pull, but no, that's not the reason).

It's really no coincidence that North Texas undergoes a substantial shift in the weather as the annual festivities at Fair Park begin to wind down. With the fair typically wrapping up toward the end of October (the 23rd of this year), this coincides with a "secondary storm season" in North Texas.

The main storm season most North Texans are familiar with is in the spring months. Rightfully so, the timeframe from March through May is known for severe storms and the most tornadoes. However, fall-season storms can also pack a punch.

This "second storm season" is characterized by storms driven along by the first strong cold front of the season. The jet stream becomes more active over the Southern Plains. This pattern helps to push powerful cold fronts deep into Texas, resulting in a drop in temperatures, a strong north wind, and thunderstorm opportunities. Oftentimes, if the right ingredients are in place, these storms can be severe.

One of the worst October storm events occurred on the evening of Oct. 20, 2019. That fateful night an EF3 tornado tore through North Dallas/Richardson and an EF2 hit Rowlett, leaving $1.5 billion in damage.

While most October storms aren't nearly as devastating as what occurred in 2019, they are noteworthy for their ability to deliver powerful winds and heavy, widespread rain. In fact, in a typical year, October is second only to May with 4.37 inches of precipitation. (Of course, October 2022 is much drier with the ongoing drought).

So back to the State Fair of Texas. When a strong, fast-moving October cold front arrives, fairgoers take note of these abrupt weather changes, especially if caught off guard by a dramatic drop in temperature. And of course, there's nothing more disappointing for a kid to have a day at the fair rained out. For this reason alone, inclement weather can often leave a lasting memory at the fair.

Thankfully, most days at the fair are marked by very nice weather this time of year. It just so happens though, late October is usually good for at least one or two big weather changes.

That's certainly the case as we look at the forecast for next week.

DFW FORECAST

A strong cold front is expected to arrive Sunday, bringing much cooler air and a good chance of showers and thunderstorms.

The timing for rain appears to be from midday into the afternoon and evening. Some heavy downpours are possible, especially late Sunday.

Rain totals could exceed 1 inch. At this point, widespread severe weather is not expected, but a couple of storms could be strong.

As for temperatures, there will be a dramatic drop from Saturday's high in the 90s to late in the weekend and early next week with highs in the 70s.