OTTUMWA — The summers of 2013 and 2014 couldn’t be much more different, at least when it comes to rain. Call it the Tale of Two Summers.
Ottumwa saw 1.78 inches of rain in the first seven days of July this year, a continuation of the wet pattern that made itself felt in June. While the area hasn’t had to worry about river flooding like other parts of Iowa, flash flooding has been a different question.
That was on forecasters’ minds again Monday. A flash flood watch included Davis and Appanoose counties, though it stopped short of including the rest of the area.
How different are things? Take a look at the numbers. Last month saw 8.02 inches of rain in Ottumwa. And that’s the official measure — some parts of town saw more. That’s 57 percent more than normal. And it’s a gargantuan 235 percent more than last June.
Percentages fail in July, at least so far. That’s because the first week of July 2013 saw no more than a trace of rain, and only on one day. So, what’s a trace?
“It’s not a measurable amount,” said meteorologist Craig Cogil of the National Weather Service in Des Moines. Since the measures go down to 1/100 of an inch, Cogil defined a trace as “essentially zero.”
The rains have come with occasionally severe weather, including Sunday night. Mahaska and Marion counties to the northwest saw a tornado warning issued for one storm. Wapello County had a severe thunderstorm warning.
Those came in an absence of even a severe thunderstorm watch. Cogil said there are multiple layers of responsibility when severe weather moves in.
“Watches are issued by the Storm Prediction Center in Norman, Oklahoma,” he said. “Warnings are always issued locally.”
There are a couple reasons for the distinction. One is simply the size of the area involved. It’s not uncommon for watches to span areas covered by multiple local offices.