*A Winter Storm Warning is in effect for Annapolis until 10 a.m. Monday morning*
The first winter storm of the season has left most of central and western Maryland with accumulating snow (ranging from around 1" in Annapolis to as much as 6-8" across northern Maryland.) During the evening hours we will experience a lull, but a broader area of precipitation will overspread the region overnight. With temperatures at or below freezing in many areas, the rain will freeze at the surface. Here are the top five questions about what we can expect from this storm tonight and early Monday morning:
Will we see any more snow from this system?
The snow has come to an end, and just about all locations in the Baltimore and Washington areas have transitioned over to sleet and/or freezing rain. Northern Maryland may still experience some light snow this evening before the changeover. All areas will see a change to freezing rain overnight.
How much ice will accumulate overnight?
The greatest threat for icing overnight will be north and west of Baltimore and Washington where 1/4 to 1/2 inch of ice may accumulate, which would snap limbs and lead to power outages. Driving conditions in these areas is strongly discouraged. East of Interstate 95, there will be a period of freezing rain overnight, but as temperatures slowly climb above freezing there will be a change to plain rain by morning. Ice may accumulate up to 1/4 of an inch inland from the bay with 1/10th to 1/4 inch of ice eastward to the bay. Icy roads can be expected in this area as well, particularly from Annapolis north and west.
When will temperatures rise above freezing?
This is the most difficult part of the forecast. Cold air "damming" can often prove to be problematic for weather forecasters. Cold air has a tendency to hold firm east of the mountains and it will take some time to bring in enough warm air aloft to push temperatures above freezing; however, this is expected to occur along the western shore first (between 3 a.m. and 6 a.m.) and then westward (around 9 a.m.) Fortunately, thermometer readings at all locations will move well above freezing during the day on Monday.
What will driving conditions be like at 6 a.m.?
Roads and walkways will have icy spots from Annapolis north and west. To the north and west of Baltimore, travel is not recommended during the early morning hours as icing will be more significant.
When is the next potential winter weather event?
On Tuesday and arctic front will surge toward Chesapeake Bay and low pressure may develop along the front. This may produce a period of snow in the region. Following this event, much colder air will overspread the bay area with sub-freezing temperatures (even during the day) through much of the week. Fresh snow cover might enhance the cold and send overnight readings into the 10 to 15 degree range.