Fifth Icing Event Of The Winter Possible Tuesday Night And Wednesday.
Strong high pressure will move from the Great Lakes Region on Tuesday, to Pennsylvania by Wednesday Morning, and then out off the Massachusetts Coastline by midday Wednesday. Clockwise flow around the high will develop a classic cold air damming event along the Eastern side of the Blue Ridge as cold subfreezing air pools over the area. Low pressure will develop Tuesday in the Western Gulf Coast and move North, spreading precipitation over most of the Southeast Tuesday Afternoon through Thursday. As high pressure continues to move East through the day on Wednesday the flow of cold arctic air will subside. Slowly warm air advection will push a warm front north through the area ending any frozen precipitation by midday Wednesday.
Enjoy today as the air will dry out from West to East ending the early morning rainfall. Downsloping winds will compress the air allowing temperatures to warm to near 60 along I-40 and into the low 60's south of I-40. There will be periods of thicker clouds today but you will see some sunshine too we think.
The weather for Tuesday Afternoon through Wednesday continues to come in a little more ominous in the last 24 hours. Ominous in that the surface temps are trending cooler. This means some areas are likely to see a decent ice storm, especially along the Eastern slope. There, a WINTER STORM WATCH has been issued for those areas already and that watch could be extended East out into the foothills. In fact, I highly expect it or an advisory to be pushed along the I-40 corridor as/if confidence continues to increase in this event through the day today. Some areas may exceed that .25 inch of ice mark along I-40 and North, and some areas along the Eastern slopes may get close to .50 inch. This will develop in about a 12-18 hour window extending from approximately 6pm Tuesday Night through maybe Noon Wednesday (Note these times may change) depending on your exact locations. Now in the graphics we are still highlighting the entire area and not each county specifics because we need to narrow down the forecast just a bit more to be able to confidently produce an accurate (90% chance of verifying) forecast by county.
Here are the graphics for this morning's package. The probabilities are completed by the Weather Predictions Center in Maryland.