The upper level low that is going to create an ugly start to the month of May is at work across the Volunteer State this afternoon, with cooling temperatures and rain for the northern plateau, and a mountain wave event for the foothills of the Appalachians.
The wind advisory that was in place for the Cumberlands has not really panned out today, but the high wind warning for the Smokies certainly has. Winds around Gatlinburg topped out at 90 mph, leaving thousands without power, most roads closed in the national park, motorists stranded on The Spur, and fueling a wildfire in Pittman Center that has grown in excess of 70 acres and is only 10% contained, despite a response from nearly two dozen fire departments.
This same weather-maker will very slowly move across the region, resulting in much cooler temperatures and rain the next couple of days.
The National Weather Service has upped temperatures a bit, and is now forecasting highs of 56 and 59 for Friday and Saturday in Oneida. And it now looks like rain chances will continue throughout the day on Saturday, as the winds pick back up. So the next couple of days are going to be ugly.
After the cool afternoons, it looks like a chance for frost could threaten the region as temperatures struggle to rebound with a trough in place over the eastern U.S. Currently, the NWS is forecasting a low of 39 on Sunday morning and 38 on Monday morning. Clouds and even a slight chance of rain should help to prevent frost formation if those temperatures bust on the low side Saturday night, but calm winds and clear skies could create concern Sunday night into Monday. Model output statistics latest run of the GFS forecast model projects a low of 37 on Monday morning, and raw data from the model is actually a touch colder, at 36.
For now, neither NWS office in Morristown and Nashville seem concerned about frost potential for Monday morning, which is good. We’ll see if that holds or if temperature expectations trend colder over the next couple of days. The good news is that Saturday’s temperature has trended slightly warmer than was originally expected, so hopefully that’s a sign of things to come. The output statistics from the latest GFS now warm us to 64 on Saturday, and NWS-Nashville is forecasting a high of 61 for its area of the northern plateau. Saturday afternoon’s temps may largely depend on how much rain and cloud cover we see as the upper low pulls away.
Long-term, the GFS model continues to stubbornly bring warm weather back to stay. We may see another quick shot of cold air late next week or next weekend, but the model is warm overall for days 8-15, despite atmospheric signs that the entire month could be cooler than average, which is what NOAA’s Climate Prediction Center has forecasted.