When officials at the National Weather Service (NWS) in Norman issued a tornado warning for Cleveland County, Oklahoma City dispatchers flipped the switch to activate all 32 outdoor warning sirens maintained by the city in northern Cleveland County.
At times, that was the right move, but not always, explained Oklahoma City police Lt. Franklin Barnes.
He cited a 2015 storm when a warning was issued for Cleveland County, but there was no immediate danger to south OKC neighborhoods. Barnes attempted to reach dispatchers, but was too late. The sirens blared, but residents had no reason to seek shelter.
In December, the Oklahoma City Council adopted a new threat-based approach to operating the citys outdoor warning sirens. Now, they only will sound in specific areas of the city threatened by a storm.
The NWS estimates the new approach will reduce false warnings by 68 percent, said Barnes, who serves as the citys emergency manager. No longer will residents hear a tornado siren blaring only to find sunshine and a blue sky.
Now when you hear the sirens, it means there is a threat approaching you or in close proximity to you, Barnes said. You need to take the sirens seriously. You need to take shelter and get more information.
NWS officials collaborated with city officials to create a new policy that ends warning parts of the city under no threat.
Officials believed false warnings caused confusion and anxiety, often leading residents to disregard warnings even when there were real threats.
The new policy matches polygon warnings issued by NWS forecasters. Depending on the storm, sirens will sound in multiple areas of the city.
Rick Smith, a NWS meteorologist, said the new policy doesnt completely eliminate over warning.
There is nothing wrong with that, Smith said. We cant always tell which streets the tornado is going down, but this will greatly reduce the number of people over warned.
Smith and Barnes presented the citys new policy earlier this month during a session at the National Tornado Summit in Oklahoma City. More than 800 professionals, including emergency managers and weather experts, attended the event organized by the Oklahoma Insurance Department.
Under the threat-based policy, the city is divided into nine sectors. Officials numbered the sectors and assigned matching cardinal directions to the sectors. For example, sectors No. 2, No. 3 and No. 5 are southwest sectors. No. 2 is southwest Canadian County, No. 3 is southwest Cleveland County and No. 5 is southwest Oklahoma County. (See map, above.)
Sector No. 7 is home to downtown and a majority of the northwest portion of OKC in Oklahoma County. Neighboring sector is No.1 is northwest Canadian County, above Yukon. Sector No. 9 is far north and represents neighborhoods in far Oklahoma City.
On the eastside, Sector No. 8 represents northeast OKC. Southeastern OKC in Oklahoma County is in Sector No. 6. Below that sector is No. 4, home to southeastern OKC residents in Cleveland County.
Things to know
OKC dispatchers can sound the sirens after NWS issues a tornado warning, on the recommendation of the emergency manager, sightings from public safety personnel or other credible evidence.
Under the former policy, NWS warnings promoted the sirens activation. Now, the sirens will give residents more warning time.
OKC will continue to test at noon on Saturdays.
Like the county-based approach, there is no all-clear siren sound. Sirens are reactivated each time another tornado warning is issued.
Officials also can activate all sirens across the area when necessary.
There are 182 outdoor sirens spread across the citys 620 square miles located across Oklahoma, Canadian and Cleveland counties.
When OKC officials activate a sectors sirens, they will communicate to other municipalities about alerts through NWSChat, a message program operated by NWS and viewed by the emergency response community. Each metro municipality operates its own sirens and is responsible for activation.
When a storm approaches, city and NWS officials recommend residents have multiple options for staying on top of the storm. Residents should be prepared to receive weather updates from NOAA weather radios, smartphone apps, television news, radios and online news.
You have to have more than one way to get your warnings, Barnes said. Sirens are just one way to do it.
Print headline: Site specific, A revised tornado siren policy cuts back on over warning.