A major winter storm will slam into the Southern Plains midweek causing widespread travel and power issues.
We first started tracking this storm last Wednesday on my live broadcasts. Over the past few days confidence in the outcome continued to increase as all models came onboard. In this discussion, I’ll break down the timing, the type, and the amount of precipitation across the area.
The Jetstream is bringing an extended short-wave trough stretched from the Rockies down into the Pacific. This brings that SW flow aloft which is filled with moisture and upper level energy (disturbances and lift) to produce precipitation. It is a classic setup for a winter storm across Oklahoma. At the same time, an arctic cold front will arrive. The combination spells trouble. The front will move through Tuesday night and we should be at the freezing point or below along the I-44 corridor Wednesday morning. Temperatures will continue to fall during the day as the cold air spreads south into Texas.
Light rain will develop late Tuesday and changeover into freezing rain (red), sleet (purple), and snow (blue) by Wednesday morning as the animation shows below (tap or click to play). The reason the I-44 corridor will see a mix of freezing rain and sleet mostly for Wednesday is due to the 850mb temperatures being above freezing. They will run about 2-5 degrees C across the area. Until they fall to or below 0 degrees, we will not fully changeover to snow. That is not expected to happen until late Wednesday evening. This means a prolonged icy time window from dusk to dawn. The good news as the model indicates, this looks to be a mostly sleet type precipitation event for the I-44 corridor, with the freezing rain just south of this boundary. This would spare OKC and Tulsa from the worst case scenario. See the graphic on the precipitation types. Sleet is better than freezing rain, as it is tiny frozen balls that although causes travel issues, doesn’t cause power issues. Freezing rain however, is that thick coating of ice you get on power lines, trees, etc that can cripple the power grid quickly, especially with winds gusting over 25 mph. (Sunday night edit: Latest short-term model data moves freezing rain line back to the north a bit more which increases ice amounts across OKC and Tulsa along I-44, watch live updates for latest adjustments.)
As a result of the snow, ice, and wind, the experimental outlook from the NWS places the area under a Moderate Impact category. However, I do expect this to be updated to a Major or even Extreme as new data arrives and the forecast is fine tuned. The take home is that it will be a mess. So watch out for hypothermia and take extra precautions while traveling if you must be out. Expect to be stranded and prepare accordingly with food, water, thermal blankets, and full tank of gas. Also make sure the wiper fluid, oil and coolant levels are checked.
Right now, very conservative snow amounts for the entire system which won’t end until late Thursday are about half a foot of snow in C OK and more across the NE. This takes into account compaction, some melting, and the freezing rain and sleet that is expected. Speaking of freezing rain, early indications are anywhere from 0.5 to 1″ of ice across parts of SE OK which would be devastating. Sleet amounts here in OKC for example may end up being half an inch or more. As we go through the next few days I will update the latest expected totals on my live broadcasts, so don’t miss them, as they will change from below!
There is so much more I could write about, but you have the big picture. The ice will also occur down into N and C TX. This includes the DFW region for Thursday. So if you expect to travel anywhere across OK, TX, AR, KS, and MO, have a back up plan and keep tabs on the road conditions. You can find Oklahoma road conditions on my website under the weather data menu tab. You can also look at power outages. Finally, be sure to use my free weather app, ATsWeatherToGo, to keep track of the radar, advisories and warnings. You can download it from Apple and Google Play stores. As far as the temperatures are concerned, expect it to be dangerously cold for a couple of days before we thaw out over the weekend. Be safe! -AT