Garrett’s Blog: Freezing Drizzle Early Friday
After a pleasant Thursday, clouds will overtake the area on Thursday night into Friday with lots of low cloud cover by daybreak. Temperatures at the surface will be below freezing and a small glaze of freezing drizzle will be possible early in the day and may affect travel on Friday morning.
This map shows 7am. Notice that Futurecast is not showing a ton of precipitation in the area. Often times, with very low cloud cover we end up with super-cooled water droplets that form ice when they come in contact with the surface. This will not be enough for power outages based on the current forecast.
The National Weather Service in Little Rock has issued a Winter Storm Watch for most of Central Arkansas where ice accumulations could be a little higher.
Overall the probabilities for ice are low. This is for accumulating ice up to .10″. Notice that not even 1/10th of an inch is anticipated in Northwest Arkansas or the Fort Smith area. The chances for ice accumulations are much higher in the central portion of the state from Little Rock up to Jonesboro and a few power interruptions are possible in this area.
This graphic is called a sounding and it shows the vertical profile of the atmosphere from the ground up. Notice the warm air on the right side of the freezing line… temperatures around 3,000ft in the atmosphere warm to around 41º but at the surface the temperature is only 28º. The red line in the temperature trace and the green line is the dewpoint trace. Where the green and red touch the air is “saturated” and clouds and/or rain is likely.
Because the atmosphere is saturated from about 1,700ft to 6,800ft rain will form in this area and fall to the ground. However, around 1,500ft it’s below freezing all the way down to the cloud and will result in freezing rain or drizzle at the surface.
Bottom line: Expect light freezing drizzle on Friday morning. Bridges and overpasses may be slick early in the day. Temperatures will warm by afternoon and rain is expected on Friday night into Saturday.