Cleanup continues; meteorologists break down ‘perfect storm’
Martin Kidston
(Missoula Current) Chainsaws continued to roar on Friday and some areas remained without power two days after a powerful storm ripped through the Missoula Valley.
Meteorologists on Friday described it as a “once-in-a-decade” event – the last being in 2015. Early estimates place the damage in the tens of millions of dollars with cars crushed, houses and infrastructure damaged, and the steep toll that hurricane-force winds took on the city's prized urban forest.
Overtime costs will also come into play as the cleanup effort continues over the coming week.
“Responders are still diligently working on resolving the issues caused by the recent storm,” the Missoula Police Department said on Friday. “We're still seeing many traffic lights out due to the power outages, and due to the extent of the damage around town, these outages may continue into the weekend.”
NorthWestern energy on Friday said it would bring in additional crews and resources from across the state to get the power grid fully up and running. Until then, city and county officials are asking residents to conserve water, particularly on the south side of the city.
“Missoula Water is still running on generators, and only 50% of water tanks are currently online,” said Allison Franz, the county's communication's director. “Residents should not water their lawns and should limit domestic use.”
Locations established to collect storm debris continued to pile up as residents worked to clear their property. The city is also working to address downed trees on public property and within the right-of-way.
With power still out in certain areas, traffic signals and other needs remain offline.
“Our officers are currently tied up with calls related to criminal activity and disturbances, in addition to attempting to help with traffic control,” the police department said. “We do not have unlimited officers and hope that the public can understand that we are unable to post officers at every traffic light to assist with traffic management.”
The National Weather Service in Missoula recorded wind speeds of 81 miles-per-hour at the airport and 109 mph on Mount Sentinel. The storm intensified as it crested Lolo peak and poured into the Missoula Valley.
“Strong thunderstorms had come up the Clearwater Mountains (in Idaho), and as they crested Lolo Peak, there was a differential temperature,” Brian Conlan, a meteorologist with the National Weather Service, told the Missoula Current on Friday. “The valley was still quite warm – 91 to 93 degrees – but the storms themselves create cool air. It just created these strong down-force winds.”
The resulting damage was widespread, stretching from the South Hills and out across the valley. Conlan said damage was most intense in the Mullan area.
“Starting in the South Hills, there's tree damage and power-line damage. That might have been on the far-right periphery of these storms,” Conlan said. “The stronger of the two cells that came up and over that area hit the Mullan area. That's where we're seeing the most damage.”
While the National Weather Service has more than a century of data on temperatures and other meteorological events, wind hasn't been recorded for very long. The instrument at the airport is around 30 years old, Conlan said, adding that “that may be the extent of the historical wind data.”
He and other meteorologists described the event as “the perfect storm,” one that required a series of events to reach the strength that it demonstrated at 9:30 p.m. on Wednesday.
“It took a lot of components to come together – the dry air, the long-term heat, a perfectly placed thunderstorm and the timing of the day – that all came together to create this event,” said Conlan. “A lot of the guys who have been here for a while are talking about 2015, so you're looking at an event on this scale once a decade.”