KEARNEY — Where did the rain come from?
Aaron Mangles, meteorologist at the National Weather Service in Hastings, attributes the unusual amount of rain Monday night and early Tuesday morning to ripe conditions and bad luck.
“In this case it was several rounds of thunderstorms that continued to track over the same area,” he said. “As new storms continued to regenerate overnight, they tracked along the same boundary for hours on end. That’s really what did it in this case.”
The moisture originated in the Gulf of Mexico.
“We won’t get the incredible amounts of rainfall if a cold front had just come through with northwest winds,” Mangles said. “We need that moisture, not only at the surface but we need that moisture available aloft as well. We have to be in a favorable air mass. In this case we did have a lot of available moisture to work with for the thunderstorms.”
Mangles noted that the conditions on Monday evening were typical of summer weather patterns.
“The thunderstorms were not more intense or more severe than thunderstorms we normally see,” he said. “It’s just the tracking that they took over the same area. This is something that will happen during the summertime at several locations. Unfortunately in this scenario it was a quite large area, an area that was susceptible to flooding. We’ve been fairly wet for a while, so while some of the water soaked in, a lot of it ended up having to run off.”
The rainfall, while not unprecedented, was unusual. Hub Territory received between five to seven inches of rainfall. Some locales in south-central Nebraska reported upward of 10 inches of rain.
“It’s not unprecedented but it is certainly is excessive and it is an incredible amount of rain,” Mangles said. “It’s certainly rare.”
As for historical records, York received about 13 inches of rain in the 1950s.
While Mangles said he doesn’t specialize in climate change, he does recognize that an unusual storm does not indicate a trend.
“It’s very difficult to attribute a single event to climate change or anything like that,” he said. “Climate change is a much larger and longer period of time. We’re looking at a single day over thousands of years. You can’t attribute a single event to climate change.”
Increased amounts of rainfall during a 12-month period could be a result of climate change, he noted.
“Just because we saw a lot of rainfall in one day isn’t a symptom of climate change. To find that change you need to take a bigger view.”
The weather service predicts about a seven-day forecast. Mangles said that central Nebraska can expect warm and dry conditions to persist through the end of the month.
“On the precipitation side, we’re favoring near to below normal precipitation over the next two weeks or so,” he said. “It looks like we’re going into a drier pattern, which is starting this week. We have only a slight chance of rainfall on Friday night.”