Understanding winter precipitation before it impacts the Big Country

BIG COUNTRY, Texas (KTAB/KRBC) – As winter weather approaches the Big Country and a wintry mix sits in the forecast, it’s a good time to break down the differences between the various types of winter precipitation and when they occur.

Let’s start with snow. Here in the Big Country, we’re expected to receive a few inches of snow heading into Thursday thanks to a second cold front and moisture. The key factors for snow formation are moisture and temperature. Snow will form when the atmosphere is cold enough to support it.

For snow accumulation to occur, ground temperatures must be at or below freezing. However, snow can still stick to surfaces even if temperatures at the ground are slightly above freezing if the conditions are right. It’s important to note that snow will not form if ground temperatures are at least 41°F.

The formation of a snowflake begins when supercool cloud droplets freeze, which are liquid droplets that have cooled below their freezing point without actually solidifying. These droplets can freeze around particles like dust or aerosols, creating a small ice crystal. As the crystal falls, water vapor freezes onto it, building out the classic six-sided snowflake shape.

Once the snowflake becomes too heavy, it falls to the ground as a snowflake unless the temperature at the surface is above freezing, in which case it might melt into rain. Snow can be categorized as wet or dry, depending on the moisture content and ground conditions. Wet snow is heavier, sticks together, and is easier to make snowballs with, while dry snow is powdery and doesn’t form easily into shapes.

Next up is sleet, which consists of tiny ice pellets. Sleet forms when snowflakes melt into raindrops as they fall through a shallow layer of warm air, but before reaching the ground, the raindrops pass through a freezing layer of air again, causing them to refreeze into pellets of ice. This typically happens due to a temperature inversion, where a warm layer of air sits above colder air. Sleet can be very hazardous because it coats surfaces like roads and sidewalks, quickly turning them icy and slick.

Finally, we have freezing rain, which can be especially dangerous. Freezing rain starts as snowflakes in the upper atmosphere, but after passing through a layer of warm air, the snowflakes melt and turn into liquid raindrops. However, unlike sleet, the raindrops don’t refreeze into pellets as they fall. Instead, they remain liquid and freeze instantly upon contacting cold surfaces, like trees, power lines, or roads. This leads to dangerous ice accumulation, creating hazardous driving conditions and causing power outages.

There is a widespread mix of snow and wintry in the forecast for the Big Country. Areas in the north, such as Knox County, are more likely to experience snow, while places further south, like Brown County, may see a mix of freezing precipitation. Stay tuned for updates on the forecast, as conditions could change quickly.