May 23: Southern Nebraska Squall Line
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Shallow moisture and advancing cold front: perfect ingredients for a weak squall line. I intercept the southern end fifteen miles southwest of Grand Island.
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Strong downdrafts make this storm outflow-dominated.
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A little later a new downdraft resembles a wall cloud.
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But soon the cold gust front reaches me, with the only threat being dime-size hail. Supercells require a balance between cool outflowing air and warm, humid inflowing air. Today outflow wins out.
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Gustnado races east across the road ahead of me. This is the leading edge of cool air rushing outward from the storm.
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As I continue driving south, another dusty gustnado crosses the road.
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Just north of Hastings, a shelf cloud advances over a picturesque farm.
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Backside of the squall line. Some stormy scenes made this chase worthwhile, but I'm looking forward to the eventual return of deep Gulf moisture to the Plains (absent since March).