As expected, storms developed in western parts of Nebraska and Colorado tonight. The strong storms are currently in the shape of a large bowing line of thunderstorms. With the threat of a derecho, the Storm Prediction Center has posted a large Thunderstorm Watch for a large area of Nebraska until 7:00am.
This watch does not include any counties in Iowa. But as the line moves east overnight, it could affect some counties in southwest Iowa. If this happens, it would likely occur closer to sunrise. The primary threat would be strong damaging winds.
By the way, if you think i made a typo when i mentioned a derecho I did not :) A derecho is a line of bowing thunderstorms over a large area that produce destructive wind damage. They can travel hundreds of miles over several hours and cause a lot of damage.
The picture to the right is what is commonly seen at the leading edge of a derecho. This shelf cloud is a common feature when the leading edge of a storm carries a strong wind gust. We’ll monitor the situation tonight and bring you any updates in case any watches or warnings are issued. If the storms continue to cause problems come daybreak, we’ll launch a live chat to bring you real time updates on the storm’s progress.