The pattern persists with another weekend system that's expected to affect the region, but as opposed to last weekend where it snowed on Saturday, this storm is forecast into Sunday. There are some similarities, but also some notable differences with this system compared to this last one. A similar cold air mass is already in place with lows in the teens, and highs only in the 20s to near freezing, but that's even a bit above the air mass last weekend where we experienced record cold. This next storm track is also riding the "Southern Stream," located in Texas right now and will move closer to the region on Sunday but will set-up just west of the Mid-Atlantic instead of moving completely south of the region. The strength of the high pressure also associated with the cold air is also very strong which could influence the track of the system, and is of similar strength to this past significant snow event.
The overall picture to take away from this weekend's forecast is to plan ahead in taking care of errands or other tasks on Saturday rather than Sunday. The latest information points to mostly wintry precipitation on Sunday, before an eventual changeover to all rain overnight Sunday into early Monday morning.
Timing: Forecasts are showing precipitation entering the region as early as Sunday morning, and lasting all day. Right now in the Storm Watch 7 forecast department, we're holding off the onset to around midday in the immediate D.C. metro.
Precipitation Type: Possible snow at onset, then a melt layer that will change the snow to sleet, possibly changing to freezing rain by afternoon, then finally changing to all rain late Sunday into early Monday.
The Dirty Details
This winter system is still about 2 days away, and is currently located in Texas.Satellite / Radar at 4PM Today
Forecasts are in pretty good agreement in moving in precipitation some time on Sunday:12z NAM Forecast Courtesy: Weatherbell 12z GFS Forecast Courtesy: Weatherbell 12z ECMWF Forecast Courtesy: Weatherbell
The biggest forecast problems to resolve will be exactly what type of precipitation will occur, amounts, duration, and air temperatures closest to the ground. This is a graphic forecasting what could fall over the D.C. metro by late morning. If this forecast were to happen, then sleet would fall over the area.NAM 12z Atmosphere Temperature Forecast
This graphic is a forecast by afternoon showing that freezing rain would be most likely to occur over the metro.NAM 12z Atmosphere Temperature Forecast
Our Futurecast forecast shows possible snow at onset early Sunday morning.Weather Central Futurecast Forecast
Later into the mid-morning hours, it depicts a mix of wintry precipitation that would most likely in this case be mainly sleet.Weather Central Futurecast Forecast
Futurecast then shows the possible mix of wintry weather, that in this case would most likely be freezing rain, or ice that would build up on trees, power lines, your car, the sidewalk, and untreated roads.Weather Central Futurecast Forecast
Summary: The overall picture is turning more towards a significant wintry event on Sunday that will impact travel conditions. Our advice at this point, is to plan on running errands or getting in activities on Saturday as Sunday is beginning to show the potential for a day that would be very difficult traveling on regional roads.