Storm cells were popping up on the radar like popcorn. Fueled by heavy, stifling Gulf moisture and cooler upper level wind shear, these storms were capable of producing twisters according to the National Weather Service storm center in St. Louis.
A tornado watch was posted by late Wednesday afternoon and the watch was to go into the early hours of Thursday morning. It could be a long night for the Hermann public safety dispatcher and for those concerned about local weather.
How would the City of Hermann be monitoring the situation as storms developed? Sirens had gone off Tuesday afternoon. How effective were they?
Hermann Mayor Robert Koerber says the early warning system is new and required some tweaking last year.
“We had some dead areas [in town] that didn’t get sirens and we had people that thought they should be able to hear them in their house—but they’re not designed for that,” he explained. “Then we had people complain that they were too loud.”
The mayor said the city purchased two new siren systems last year to fill the gaps in alarm coverage. The alarm system is now coordinated and covers the entire city.
The omni-directional 121 dB sirens were purchased and are maintained by L & B Electronics in Eldon, Mo., at a cost of $12,950 per siren, or $51,800 for a group of four. They have a range of 1.75 sq. mi., at 68 dB.
City Administrator Mark Wallace says if the town is threatened by a tornado, the dispatcher will set off “tones,” a limited audio emission that cuts across the whole bandwidth in a communications network that lets law enforcement and first responders know about the warning. An example would be an interruption on a television or radio that starts with a set of attention-getting tones, followed by a message, in this case, from the NWS. He says only a tornado warning warrants siren activation and those are stationed at five locations throughout Hermann: the 1st Street alley, behind St. Paul Church; near the Middle School by the lift station; near the cemetery at the top of the hill on Gutenberg; near the senior center at See Tal and in the City Park near the pool.
Put to the test
Last Tuesday, at around 5 p.m., Hermann residents heard the sirens, but not just any sirens. They warn of impending town danger from tornadic activity, so take cover immediately!
But early Thursday morning around 1 a.m., when turbulence was detected in a storm cell that nicked the northeast corner of Hermann before it crossed the river into Montgomery County, the sirens remained silent.
Rhineland’s residents heard their local sirens, but all Hermann residents got, if their smart phones were activated to receive notices from the National Weather Service, was “Tornado Warning! Northern Gasconade County and Southern Montgomery County - Take Shelter Immediately!”
This was the same night an EF-3 tornado, with an estimated windspeed of 160 mph (257 km per hour) hit the town of Jefferson City. Weather forecasters had predicted days in advance of a possible severe weather outbreak. Local television stations were tracking the storm front well in advance of the estimated time of arrival and it was reported the sirens went off at 11:10 p.m.—30 minutes before the first property damage was inflicted, according to an Associated Press news story. Gov. Mike Parson credited the early warning system for saving lives, but who or what activates the sirens, whether in Jefferson City or Hermann?
It starts with the NWS
All severe storm warnings and watches start with communication from the National Weather Service (NWS). That information is pushed out digitally to not only public safety officials, but also to citizens that have various weather applications on their cell phones.
“That warning only clipped part of the county, but the phones went off because it is based on GPS (Global Positioning System),” said NWS Meteorologist Melissa Byrd. “If you’re within the box of the tornado warning, your phone will go off, stating there is a tornado warning.”
She says the National Weather Service depends on Doppler Radar to determine the intensity and motion of precipitation within a thunderstorm cloud. Mathematical algorithms help them to determine turbulence.
“We can’t actually see the tornado, so we have to rely on [severe storm] spotters on the ground,” she said. If this appears primitive, Doppler Radar is still a very good predictor of tornadoes.
A May 1973 tornado devastated Union City, Okla., just west of Oklahoma City. It was the first time, a Dopplerized 10 cm wavelength radar from the National Severe Storm Laboratory (NSSL) documented the entire life cycle of the tornado. The researchers discovered a particular type of rotation in the cloud aloft before the tornado touched the ground. NSSL's research helped convince the National Weather Service that Doppler radar was a crucial forecasting tool.
Once the NWS sends out initial watch and warning information, they continue to monitor current storms for intensity and imminent danger to people and property.
The Missouri State Highway Patrol (MSHP) takes this NWS information and sends it out on their Missouri Universal Law Enforcement System (MULES) communications system to regional dispatch services like Owensville and Hermann.
A spokesperson for MSHP said, “It’s not something we would call in and say, ‘There’s a tornado warning for your area.’” “They (your dispatchers) get the information from our system and do whatever their protocol is.”
In Hermann, Communications Supervisor Vera McDowell shares how that works in Gasconade County.
Smart phone confusion
“All 911 calls in Gasconade County go to Gasconade Central, located in Rosebud,” she explained. “For Hermann Fire Department, Ambulance and Police, those calls are transferred up to us so we can handle them.”
As far as handling alerts like tornado warnings, “We have our MULES system and they (Owensville) have theirs,” she said. “We both get the information across our computers, but Gasconade Central has nothing to do with setting off [early warning] tones or sirens. McDowell says this responsibility lies within the City of Hermann Dispatch.
That being the case, on early Thursday morning, when Hermann residents received the tornado warning notice on their cell phones, they also might have wondered why there was no tornado siren.
“The Hermann zip code is not just the City of Hermann,” said McDowell, “but also includes McKittrick, Gore, Case, Bay and Swiss.”
She said the storm cell the NWS was monitoring came through Chamois, Rhineland, McKittrick and High Hill.
“At the same time frame, you have a severe thunderstorm warning in effect for Hermann,” she explains. This tells you, the strong part of the storm was going north across the river and the part of the storm that wasn’t as severe, was hitting Hermann.
“It’s not unusual for southern Montgomery County and southern Warren County to be within that range identified as “the Hermann area,” said the dispatcher, or for that matter, “northern Gasconade County,” as identified in the tornado warning.
The bottom line according to McDowell is there was a dispatcher in the Hermann Police station early Thursday morning monitoring the storm, using proper protocol to make a decision whether to sound the siren or not.
“For us, the cell phone is the least accurate of all the [early warning] sources, as to who is going to be hit [by a storm],” she stated.
She says if emergency broadcasts go off on the phone, and they haven’t seen anything that corroborates the warning, for instance on radar, they’re going to investigate.
“Because this was so close on the other side of the river, that’s why all the phones went off in Hermann, saying ‘Tornado Warning for your area, but the NWS did not issue a tornado warning for Gasconade County.’”