Have you ever heard of the term WetBulb Globe Temperature? Likely not, but it’s serious business at Wright-Patterson Air Force Base, and again this year, it could force marathon organizers to call the race quits if WBGT reaches a certain level Saturday.
Storm Center 7 Meteorologist Jesse Maag explains what it means.
“Oftentimes on hot days, meteorologists will talk about the heat index, or the ‘feels like temperature.’ Air Force meteorologists have another method of measuring heat and they go to pretty great depths to calculate it,” Maag said.
Last year, the Air Force Marathon released a statement about how the heat could affect the race:
Maag explained the heat index accounts for both the temperature and relative humidity, disregarding other atmospheric factors.
The wet bulb globe temperature, or WBGT, used by the Air Force, takes into account not only the air temperature and relative humidity, but also the wind speed, sun angle and cloud cover.
By using more variables, the Air Force expects to have a more accurate representation of the way the air feels on a hot day.
The scale is slightly more complicated for the WBGT than the heat index, however. It doesn’t measure how the air feels like the heat index. For example, a calculated WBGT over 82 degrees is considered extremely dangerous.
That is the temperature at which the Air Force Marathon organizers would stop the race, according to an alert sent to participants Friday.
So what will the WBGT and forecast be on Saturday for the 2019 Air Force Marathon?
Storm Center 7 Meteorologist Kirstie Zontini said the sunrise will be at 7:23 a.m. with early morning temperatures in the upper 60s.
By midday, temperatures will be in the low 80s. The WetBulb Globe temperature at noon will be in the low to mid-70s.
This is in a range where race officials would advise runners to slow down but it isn’t high enough that they would stop the race.
Early afternoon temperatures will keep climbing into the upper 80s. The WetBulb Globe temperature at noon will be in the upper 70s.
This is in a range where race officials would advise runners slow down and watch for any course changes, but it also isn’t high enough that they would stop the race.