GREENVILLE, N.C. (WNCT) – 9 On Your Side got a great comment on our Facebook page Sunday during the coastal storm.
Theresa says: “39 degrees in Raleigh equals snow and 36 degrees in Greenville equals rain… that doesn’t make sense!” Well, when talking winter weather, you have to look at temperatures not just at ground level. We also observe temperatures several thousand feet above to know what will end up falling from the sky to the ground.Coastal storms often draw in warmer air from the Atlantic Ocean and transport it inland.
Coastal storms often draw in warmer air from the Atlantic Ocean and transport it inland.
Warm air is less dense than cold air, so initially, the warmer air will ride up and over colder air at ground level. Slowly but surely, that warm air can erode the cold air away, warming things up at the ground.
It was just cold enough across inland areas of eastern North Carolina Sunday morning to start with some sleet. As temperatures a few thousand feet up warmed just above freezing, a cold rain started to fall in Greenville by late morning.
Back to the west in Raleigh, the warm air intrusion wasn’t nearly as strong but there was just enough right above the ground to partially melt some of the snowflakes, causing a mix of sleet and snow to fall in places like Goldsboro, Wilson, and Raleigh.
Bottom Line: Temperatures, not just at the ground but several thousand feet up above the ground determine winter precipitation type.