Warmer air atop colder temperatures at ground level is setting the state for a dangerous icing situation across much of central, Downeast, and western Maine, although most of the state will experience at least some freezing rain tonight and Sunday. Colder and quieter weather will return for Christmas, however.
Another wave of low pressure - the strongest one of the handful that have come through northern New England during the weekend thus far - will bring precipitation to the entire state. At issue, record high temperatures across the Plains and Eastern Seaboard running into cold air from Canada. Cold air, being dense, forces the warm air over the top of the cold air near ground level. As the precipitation moves in and falls, it melts in the warmer air, then refreezes either just before hitting the ground (sleet) or on contact with the ground (freezing rain/icing).
GRAPHICS: Ice and snow accumulations, timeline, and effects icing may have.
Rain will pick up in intensity overnight and fall into the colder surface temperatures in place across central Maine. As this happens, winds will begin to switch into the NE, allowing the colder air to begin "draining" southward into the Midcoast and southern Maine. By far, the heaviest icing will occur through central Maine, however, with enough of a temperature drop, much of Cumberland, Androscoggin, and Sagadahoc Counties will manage a few hours of freezing rain late tonight and Sunday.
The precipitation will slowly wind down Sunday evening. Temperatures during Sunday night won't drop much, if at all, so at least there won't be a flash freeze of any remaining water (although temperatures throughout central Maine will stay in the 20s anyway).
Monday, another wave of low pressure rides along the same boundary that presently is parked over Maine, although by Monday, the front will be just offshore. This means another round of showers close to the coast and another bout with light freezing rain, sleet and snow for the interior.
Expect drier and quieter weather just in time for Christmas Eve and Christmas Day, although it will turn colder.
Programming Note: The Morning Report on Sunday will go into STORMCENTER mode and begin at 5am. We will be live through at least 8am and streaming online. We can also be found simulcasting on 1470 AM (Lewiston-Auburn area) and 870 AM (Greater Portland).
- A.J. Burnett