Headlines
An unsettled weather pattern continues
Watching a system for the end of the week
Turning colder next weekend
Meteorologist Mark’s Wx Vlog
48-Hour WX
Seven-Day Forecast
Daily Forecast Summary
Today: Morning showers, then mostly cloudy.
Monday: Partly cloudy and pleasant.
Tuesday: Morning sprinkles are possible, followed by decreasing clouds. Partly cloudy skies are expected by afternoon.
Wednesday: Clouds increase through the day. Mild.
Thursday: Rain showers likely.
Friday: Rain and snow mix possible. Colder.
Saturday: Partly cloudy and colder.
Meteorologist Mark’s Wx Thoughts (New!)
It’s a cold morning on the plateau and I wouldn’t be surprised to see a snowflake or two out there. No accumulation, though.
I’m still eyeing the end of the week. Any precip that falls looks to be on the very light side of things. Models still show a cold pocket of air aloft moving over Thursday night and Friday that could produce some light wintry precip. I’ll wait for more data today and tomorrow before using the “snow scale”. The data right now would suggest any wintry precip would be under an inch. I’ll keep an eye on things!
Next weekend is looking cold.
Wx Threats for the Next 7 Days
On This Day in Wx History
1961 – A three-day long ice storm was in progress over northern Idaho that produced an accumulation of ice up to eight inches thick! That remains a U.S. record. Heavy fog, which blanketed much of northern Idaho from Grangeville to the Canadian border, deposited the ice on power and phone lines causing widespread power outages.
Almanac
Yesterday’s National Temperature Extremes
High: 86° at Immokalee & Miles City, Florida
Low: -25° at Antero Reserve, Colorado
Today’s National Wx Hazards
Freezing rain and snow will affect the Northeast today. Another area of accumulating snowfall can be found across northern Minnesota. More accumulating snowfall be found across the Northwest.
Tomorrow’s National Wx Hazards
Wintry precip will affect both the Northeast and the Northwest. Most of that precip will be on the light side.
Sunday Story
An arctic cold front crossed the plateau on Christmas Eve and created an extremely dense fog that prompted a surge of comments on my social media.
Fog is one of nature’s most dangerous forces. While fog is just a collection of tiny water droplets suspended in air, it can be a very dangerous weather element to drive through.
Fog causes nearly 40,000 vehicle accidents each year in the US, with around 600 people losing their lives in those crashes.
To understand how fog forms, one must understand how water vapor works. There is always water vapor in the air. Even the driest deserts have some moisture in the air. In order for that moisture to condense the air must be cooled. Air is always cooled to saturation.
Relative humidity is often lowest in the afternoons, when temperatures are warmest. Humidity is often highest in the early mornings, when temperatures are coolest. Air being cooled to saturation is one reason why there’s dew in the mornings.
Like any cloud, fog is always formed when air is cooled to saturation. When a strong cold front moves in and quickly cools the air, fog can easily form, like it did on Christmas Eve.
We make fog with our bodies on cold winter mornings. Just exhale your hot breath into the colder air and you suddenly make a fog cloud.
Remember to always drive with your headlights on low beams when driving in fog. Brighter lights lead to more light reflected off the fog, making it harder to see to drive.
Unlike Santa, we don’t have a red-nosed reindeer at the front of the car, leading us safely through the fog. Instead, you’ve got those low beam headlights to guide the way!
