Covid-19 is impacting how weather experts issue hurricane forecasts

July 25, 2020 steven

The problem isn’t so much with normal, day-to-day operations, but rather with big events, when staffing at National Weather Service (NWS) offices can often double or triple what it normally is.

“Normal staff for our office is about 2-4 people depending on the shift, but during big events such as tornado outbreaks and tropical systems our staff could surge to 7-8 people,” explains Kyle Thiem, meteorologist at NWS Atlanta office.

Yet adding more people into an enclosed space creates problems in a world with Covid-19. So how do they allow for the added staff while not compromising their safety or the life-saving information they put out?

“We took steps early to protect the facility to ensure a safe environment for our staff,” says Dennis Feltgen, a communications officer for NOAA. “This includes following guidelines to have staff work at home to limit exposure to others. We have also followed the guidelines on distancing, both at workstations and common areas, and we will continue to do our best to keep our staff safe and ready as the hurricane season continues.”

In some cases, having the employees work from home is also an option.

“Non-essential duties are being handled remotely,” shares Maureen O’Leary, spokeswoman for the National Weather Service. “To minimize cross contamination within an office we are staggering shift changeovers and doing “remote” hand offs wherever possible. A forecaster completing a shift and one arriving for the next shift exit and enter through different doors to minimize any contact. The health and well-being of our workforce is our top priority.”

Ingredients are ripe for an active season

That hurricane season is likely to be a more active one than usual. It has already been a record-breaking hurricane season, and we haven’t even reached the peak, which generally falls on September 10th.

In addition to keeping their staff safe during coronavirus, NOAA has also added information to its normal forecast guidance to the public. The most discernible is its updated hurricane preparedness checklist to include two new items: a face mask and hand sanitizer. Many offices have also been vocal about finding your hurricane shelter location ahead of time, since some shelter locations may have changed from previous years due to Covid-19. For example, smaller shelters used before, may be moved to larger facilities to allow for more adequate social distancing.

Less data makes forecasting more difficult

Coronavirus isn’t just impacting the employees, but also the forecasts themselves. The forecasts that meteorologists create for hurricanes rely in part on computer models. These models are only as good as the data that is put into them. This data comes from a variety of tools, including aircraft, cruise ships, satellites, buoys, weather balloons, ground stations, and radar. The Covid-19 outbreak has significantly reduced the amount of data we get from two of those tools — aircraft and cruises.

So meteorologists are at a disadvantage, especially over water, where these observation tools are already limited. Over land, they can just launch extra weather balloons or add additional ground stations to help make up the loss of flight data.

But they can’t do that over water. Buoys are unevenly distributed and are notorious for data errors. These floating devices alone can’t provide a complete and accurate picture of a particular region of the ocean. Meteorologists need the combination of all available tools to accurately understand the state of the atmosphere across the globe at a given point in time.

According to the European Centre for Medium-Range Weather Forecasts (ECMWF), if all flight data was gone, the accuracy of forecast models would decrease by as much as 15%.

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