Cold air has invaded the ArkLaTex after a weekend of heavy rain.  Freezing rain will cause travel issues for part of the area during the next few days. A Winter Storm Warning is in effect for the West and Northwest edges of the area where ¼” of ice is possible.  

Why ice and not snow:  A rather shallow layer of cold air is invading the ArkLaTex.  A series of disturbances will continue to bring waves of precipitation for the next several days.  With temperatures close to freezing over parts of the area, you might be wondering why we are expecting ice and not snow.  The answer is in the depth of the cold air.  It appears that it will be shallow enough that any precipitation that falls from the clouds be it snow or rain will melt as it encounters a layer of warm air above the surface where temperatures are above freezing.  At the surface where the temperature is below freezing, that rain will freeze.  

As the graphic above illustrates, the cold air would have to be much deeper for the snow falling from the clouds above to stay snow all the way to the ground.  If the cold air were a little deeper, the rain could freeze before hitting the ground resulting in sleet.  We could see a little sleet in spots during the next few days, but most of the precipitation will be rain or freezing rain.  

Keep an eye on the thermometer:  The only difference between rain and freezing rain is the temperature at the surface.  If the temperature is above 32 you are seeing rain.  If it’s 32 or below, it’s freezing rain.  So if you have to travel for the next few days, keep an eye on the thermometer.  It doesn’t take much ice to make travel somewhat dangerous.

Futurecast: Futurecast shows that most of the area will likely stay all rain for most of the next few days.  The main issues with ice could develop over the northeastern, northern, and western edges of the area. Why just the edges?   All of us would likely be worried about ice IF the ‘mountains’ in E OK and W AR didn’t exist.  A shallow cold air mass like this one is forced to go around the Ouachitas to our north.  Consequently, sometimes they ‘protect’ much of the ArkLaTex from experiencing as much winter precipitation.  You can see that Futurecast shows where ice (areas of pink) will be possible mainly over the northern and western edges of the area. 

Ice potential:  Here are a few outlooks from the Weather Prediction Center that I think show a good representation of what we can expect from now through Tuesday night.  The first above shows the chance of seeing ANY ice.  This is important for travel.  Even the smallest amount of freezing rain can make roads and especially bridges slick. A little ice will be possible in Shreveport.  The risk of ice increases as you look north and west. Below is the chance of seeing at least ¼” of ice accumulation.  This level is important as we tend to experience issues with power outages where ice accumulations exceed ¼”. The chances of seeing this much freezing rain will be highest over the western edge of the area in SE OK and NE TX.

Finally,  here below is a breakdown from WPC of what I think is the most likely outcome of ice accumulation.  Amounts will likely approach or exceed the ¼” threshold over the west and northwestern edges of the area.  Texarkana will likely see amounts of nearly 1/10”.  If Shreveport sees any, it will be very light.

Rainfall potential: Another issue that we will have to keep an eye on is the potential for heavy rain.  Futurecast shows that most of the area will receive 1 to over 2” from now through Thursday. We should finally see some sunshine return to the area by the end of the week. The good news is that we will also warm up. Highs should return to the 60s by the end of the weekend.