After strong winds reported to be up to 111 mph caused damage in Derby early Sunday morning, the National Weather Service surveyed whether the storm spawned a tornado.
The Wichita office of the weather service said officials would be in Derby on Sunday afternoon to conduct a survey to determine whether damage was caused by extreme straight-line winds or a tornado. A 111 mph wind gust with sustained winds of 76 mph was recorded at around 5:09 a.m. in the southeastern Sedgwick County town at a Weather Underground station, according to NWS local storm reports.
But the National Weather Service later reported that a damage survey team found 75 to 90 mph straight-line wind damage primarily to softwood trees across southern and southeast Sedgwick County. The storm hit between about 4:54 a.m and 5:06 a.m., and left a path of damage about half a mile to a mile wide that stretched along a nearly 11-mile path from northwest of Peck to Derby.
“We think the 111 mph gust was too high,” the Wichita branch of the weather service said in a tweet. “As winds this strong would have caused more extensive structural damage.”
No injuries were reported from the storm, said Capt. Hector Gonzalez of the Derby Fire Department. But reported damage included pole fires, downed power poles, uprooted trees, broken tree limbs, trees falling on houses and one business with its roof blown off.
“Those trees didn’t stand a chance,” Gonzalez said, referencing the reported wind gusts and heavy rain over the past month that made the ground soft. Of the trees that fell on homes, most caused little or no structural or otherwise major damage.
The Saturday to Sunday rain brought 1.5 to 3 inches of precipitation throughout Sedgwick County, according to an NWS rainfall map of the 24 hours prior to 7 a.m. And last month was the second-wettest May on record, the weather service has said.
The worst of the damage was in an area stretching from K-15 to Rock and Meadowlark to Madison, Gonzalez said.
The fire department captain said the worst building damage he saw was the roof ripped off Derby Quik Lube.
Sedgwick County officials said in a tweet that emergency management was investigating a siren malfunction. But county spokeswoman Kate Flavin said there was no system malfunction and the sirens activated as designed.
A dispatcher activated the outdoor sirens county-wide at around 4:45 a.m. after the NWS sent out information on incoming severe weather, Flavin said. The activation was canceled about 30 seconds later when it was determined that the threat was primarily for Sumner County.
About 15 minutes later, sirens were activated in the Derby area after the weather service issued a tornado warning for that area, Flavin said.
“We apologize for any confusion this may have caused this morning; there were no system malfunctions and the sirens activated as designed,” she said. “Note that tornado sirens are not intended to be the first or only warning for residents. Local media, weather radios, or weather apps should also be monitored during severe weather.”
As of 10:30 a.m., Westar Energy reported 72 power outages affecting 2,820 customers in the immediate Derby area. In Wichita and the surrounding area, Westar reported over 200 outages affecting over 4,800 customers. The utility company said on Twitter that power is expected to be restored to all customers in the Wichita area by noon Monday.
Damage reports to the National Weather Service included tree limbs and power lines down across the area, a 2-foot-diameter tree on a road in west Wichita, a fence blown down in Goddard, baseball-sized hail in the Hutchinson area and street flooding in Rose Hill. A tornado was reported to have touched down at around 3:37 a.m. about a mile south of Harper.
“Public Works and emergency crews are working to clear roadways and downed power lines at this time,” Derby officials said in a Facebook post. “Please check back for further updates this morning.”
The weather service forecast for Wichita, as of Sunday morning, calls for a 30 percent chance of rain Sunday afternoon, mainly after 4 p.m. Some of the storms could produce heavy rain. Across the area, rain, hail, strong winds, flash flooding and tornadoes are possible.
Photos and videos of storms and damage can be submitted to The Eagle online at www.kansas.com/customer-service/submit-photo/.
This is a developing story and will be updated as more information becomes available.