Ice, snow, there is a chance

Winter Weather Outlook for the end of this week

Ice, snow, there is a chance

WICHITA FALLS, TX (RNN Texoma) - Snow you’re saying there’s a chance? I am not going to lie this forecast is very difficult so I wanted to share my thoughts. Winter weather is never easy to forecast. Especially in Texoma. That is because it not as simple as having a temperature below 32 degrees. You can get snow when it is 40 degrees. You can get rain when it’s 29 degrees. The forecast is very dependant on what is happening in the upper atmosphere. Models struggle with the upper atmosphere because we only take troposphere readings twice a day. Temperatures are collected at the surface every 5 minutes at climate sites across the country. There are more than 30 Primary Local Climatological Data Sites on the ground across Texas. There’s only 6 locations that launch a weather balloon. The weather balloon carries a radiosonde that measures temperature and dew point throughout the troposphere. This is the data that is key when it comes to forecasting snow. Models can easily be off because this data is so far spread out, and only collected twice a day. So tweaks can’t be made as easily to improve the forecast.

This graphic explains how we get snow, sleet, freezing rain, or just rain. We typically have an inversion in the upper atmosphere. This is a warm layer of air. If there is a very small warm layer we can get snow. We get sleet when the warm layer is large enough to partially melt the snowflake. Freezing air closer to the surface causes the partially melted snowflake to refreeze as sleet. If the snowflake melts completely, but the temperature at the surface is below freezing the rain will freeze on contact and we get a layer of ice. If it’s not cold enough at the surface we just end up with rain.

At the end of this week I am confident we will see rain across the state of Texas and into southern Oklahoma.

The weather pattern shows a low pressure trough digging deep enough to bring plenty of pacific moisture into Texas. So I am certain we will start to see isolated showers as early as Thursday and widespread rain on Friday. Friday night is when the forecast becomes more complicated.

This isn’t the strongest low pressure. It won’t pull in a ton of arctic air the way that it is forming off the southern coast of California and moving east. If the low pressure formed further north and then dropped south, I would be much more confident in my winter forecast. I am confident temperatures will drop, but it will be a close call whether or not we see it cold enough.

There are two major long range weather models we use. The GFS keeps us above freezing.

The Euro does drop us below freezing on Saturday.

The GFS is usually a little warmer, so I am more confident in the European model.

Both models agree that we will see 1-2 inches of rain. The disagree on temperatures and therefore the snow forecast is different. Right now the GFS models keeps all the winter weather in the Texas panhandle and northwest Oklahoma.

The european model is more hopeful for snow, but as you can see it will be a quick cutoff between who sees snow, and who doesn’t.

If you kept reading this long here are my thoughts. I am confident we will see 1-2 inches of rain starting Thursday night, ending Sunday morning, but the winter weather details still need to be ironed out. Weather forecast are more accurate 3 days out and most accurate the night before, so check back for an update.

Sincerely,

Carly Smith, First Alert Meteorologist

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