April 16, 2014

State could see the lowest number of tornadoes ever this year

Iowa’s on the verge of setting a new record for fewest tornadoes in the calendar year. Jeff Johnson, the warning coordination meteorologist at the National Weather Service, says Iowa’s tornado season is essentially over already, though he’s quick to remind that twisters can appear during any month of the year.

“Right now, we’ve seen 15 tornadoes in the state of Iowa for 2013,” Johnson says. “Compared to normal, the average number we get here is 47 so we’re quite a bit below normal.” This year began with one of Iowa’s coldest, wettest springs on record, which is not conducive to tornadoes.

“Then, we did get active for a while in May and June which we typically do and that’s when we picked up the brunt of these tornadoes,” Johnson says. “Then, much like 2012, we got into a drought situation and the lack of thunderstorm activity really put the kibosh on these numbers.”

Iowa’s current record for fewest tornadoes in a year stands at 16 — which we reached last year, which was also year of a severe drought. The new record looms, but we’ll have to remain tornado-free through January. Johnson says, “Yes, 15, if we didn’t pick up any more and that’s a big ‘if,’ we could still get tornadoes in the fall in Iowa, but if we didn’t 15 is the least number in modern times.” This year’s first tornado hit on May 19th and the last one was on June 26th.

That span of 38 days would be Iowa’s shortest-ever tornado season, beating the old record of 40 days set in 2012. Combined, last year and this year have produced the lowest back-to-back yearly totals in modern history — 16 and 15, respectively. Earlier this year, Iowa also set a record for most consecutive days without a tornado at 359. The previous record of 355 straight tornado-free days was set between 1955 and ’56.

While tornadoes are typically a summer phenomenon, they can strike any day of the year. One of the more recent late-season outbreaks was the Woodward/Stratford tornadoes on November 12th of 2005. By contrast, Iowa’s worst year for tornadoes was 2004 when 120 were recorded.