Boise awoke to thick fog Wednesday. Here’s when it’ll disappear … and when it’ll be back
Treasure Valley residents woke Wednesday morning to a thick fog enveloping Boise and its surrounding cities, reducing visibility to less than a quarter of a mile.
The National Weather Service issued a dense fog advisory at 7:28 a.m., warning that the fog would last until about 11 a.m. But Weather Service meteorologist Sophia Adams told the Idaho Statesman that the fog could stick around for a couple of hours longer.
“Typically, what we look for to mix it out is after the sun rises, typically we get like some winds to kind of start to mix down a little bit,” Adams said. “But the winds aren’t starting quite yet, so it could be a little later, like around noon to 1 p.m.”
The fog results from the inversion conditions that have caused gloomy mornings in Boise for much of December. A typical inversion will see a thick layer of low-lying clouds sit above the city, but conditions at the surface remain clear.
But rain earlier this week has kept the ground moist, Adams said, creating the dense fog.
Wind and evaporation via the sun’s heat should clear the fog out later Wednesday, but it likely won’t be the last time we see fog this week. Adams said she expects fog to remain into the evening in higher terrain and to return to the lower valleys overnight and into Thursday morning.
A system Friday night is expected to move into the area, providing a 70% chance of rain Friday and clearing out the foggy conditions. But as the temperature drops into Saturday morning, Adams expects the rain to turn into snow.
Little to no snow accumulation is expected Saturday morning, according to the Weather Service.
“We are seeing a bit of a broader system with stronger winds near the surfaces, stronger westerly winds, and that should clear out the lingering inversion by Friday afternoon,” Adams said. “But there is going to be quite a bit of rainfall with that in the valley.”
This story was originally published December 20, 2023 at 10:42 AM.
