WASHINGTON — Tuesday will start with some rain, but as much colder air arrives, it will mix with some wet flakes and perhaps a brief period of snow later in the morning. Roads will stay wet in the D.C. metro, but there could be a coating of snow on the grass, mulch and any elevated surfaces.
Here's what you need to know about the timing, and what it means for commutes.
- Overall Timing: Tuesday until 2 p.m.
- What: Light rain changing to a mix, and then a brief period of snow
- DC Metro Timing for Snow Possible: Tuesday 9 a.m. to 1 p.m.
- Road Conditions: Just wet
- DC Metro Accumulations: Up to a coating on grassy and elevated surfaces
- Mountains Accumulations: 1 to 4 inches
For the D.C. metro area, the critical timing for this changeover from rain to a mix and snow is from 9 a.m. to 1 p.m.
How Much Snow
Below is our weather model comparison of snowfall, updated Monday evening. We're not expecting accumulating snow, but there could be enough for a light coating on the grass and elevated surfaces. The up-slopes of the mountains will get a few inches of snow.
Rain and Snow Timeline
Tuesday 9 a.m. to 11 a.m.: As temperatures fall through the 40s and into the 30s, we'll begin to see a transition from rain to a rain/snow mix and then to some wet snow. For the D.C. metro, this change begins at the end of the morning commute. The moisture will be running out quickly northwest, but temperatures drop to the 30s and low 40s. The roads will be just wet, but if it snows pretty consistently for over an hour, you may pick up a coating on the grass or elevated surfaces. Up-slope snow showers are ongoing in the mountains west of the divide.
Tuesday Noon to 2 p.m.: The inner D.C. metro sees the back edge of the snow/rain ending in this time frame, but the mix/snow is still ongoing southeast of town in parts of Southern Maryland and the Northern Neck. Again, even if it's snowing, temperatures themselves are marginal in the upper 30s. The roads will stay just wet. Up-slope snow showers are ongoing in the mountains west of the divide.
Tuesday 2 p.m. to 5 p.m.: The last of the mix/snow exits Southern Maryland at the beginning of this time frame. Although the later afternoon is dry overall, it's turning blustery and colder. Temperatures will be in the mid to upper 30s, but factoring in gusty northwest winds, it will feel like its in the upper 20s and low 30s. There will be snow showers continuing in the mountains. Some snow showers may successfully make it down into northwestern suburbs.
Arctic Air Incoming
Outside our possibility of the first flakes of the year, Tuesday will be turning much colder as Arctic Air rolls in. It will be blustery with winds at times gusting 20 - 30 mph. Factoring in the winds and temperatures falling into the 30s, the feels-like temperatures will be dropping through the 30s during the day.
Into Wednesday morning, the feels-like temperatures drop colder into the teens to low 20s.
By Wednesday afternoon, winds are lighter. The feels-like temperatures will be in the low 30s, which is only a handful of degrees lower than the actual high temperatures in the 30s.