Overview: A weak area of low pressure slipping by to our south has drawn up just enough moisture to produce some wet snow in our marginally cold air mass. The steadiest snow should occur from D.C. and points south, likely enough to coat grassy areas to as much as 1” southwest of D.C. but not accumulate on roadways for the most part but Update: some slick spots and slush are possible on roads during moderate to heavy bursts this evening. Temperatures are generally in the mid-30s (update: but are falling into the low 30s ). Some of the snow may mix with and change to sleet and/or rain as the afternoon wears on mainly in D.C. and points south (when intensity lessens).

When does this end? Most likely between 6 and 8 p.m. from southwest to northeast.

4:45 p.m. update: This live blog has concluded. See our PM Update for the latest forecast

4:30 p.m. update: Snow continues throughout the region, with a moderate to heavy band just south of D.C. through Burke, Springfield, Alexandria and into Prince George’s and Anne Arundel county south of Route 50.

Link: Live video of snow at the White House

User snow gallery: Submit your photos and view others

We are seeing increasing reports of some snow sticking to secondary roads and sidewalks, especially west of the beltway. Please use caution this evening as temperatures fall back into the low 30s and the sun sets, making accumulation easier.

Keep reading for older storm updates...

4:00 p.m. update: Steady light snow continues over the metro region, with some areas getting “fat flakes” and snow falling at a moderate clip from time to time. Accumulation on grassy areas has become common-place, with snow sticking on tree limbs and parked cars as well.

At higher elevations west and northwest of town, we have gotten some reports of snow sticking to secondary roads so use caution traveling, especially in western Prince William, Loudoun, and northern Fauquier counties

3:20 p.m. update: Light snow, with some embedded moderate areas, now covers much of the metro region from Montgomery county and to the south. While temperatures remain above freezing, snow may have a little easier time accumulating as the sun goes down, mainly on grassy areas. Some slush on roads during heavier bursts cannot be ruled out, especially in the colder north and west suburbs.

When the precipitation lightens up, it may mix with rain and/or sleet and we’ve seen reports of this happening mainly in downtown D.C. and south of town.

2:45 p.m. update: Snow has re-developed in Prince William and Fauquier counties and extends as far north as central Loudoun county . This area of snow will push through Fairfax county and the District over the next couple hours, and even graze areas a bit farther north than earlier. Central and southern Montgomery county may see some light snow in the next hour, which may even reach into southern Howard county and northern Anne Arundel county (but remaining south of Baltimore mostly). This remains “scenic” snow and should not cause problems on roadways.

Moderate snow continues in southern Prince George’s county, northern Charles county and northern Calvert county. This region of southern Maryland should continue to get snow for the next several hours although there’s a chance it mixes with sleet and rain.

2:15 p.m. update: North of I-66, snow has tapered off. However, moderate snow continues in eastern Prince William county, across southern Prince George’s county and into northern Calvert county. In these areas, a slushy accumulation is likely mainly on grassy areas, though we can’t rule out a little slush on the road when the snow is heaviest.

Another area of snow and/or mixed precipitation is developing to the west and may clip the region between 3 and 5 p.m. This little event isn’t over yet.

1:45 p.m. update: A narrow band of moderate snow extends from just east of Culpeper northeast through Manassas and into Springfield and Alexandria. It will move east into central and southern Prince George’s county in the next 30-60 minutes. Where the heaviest snow is falling temperature may drop to 33 or 34 and create a little slush on the roads briefly, so use caution.

The snow has a sharp northern cutoff - from extreme northern Fairfax county through southern Montgomery county and northern Prince George’s county.

1:15 p.m. update:Reports from blog, Twitter and Facebook followers indicate it’s snowing hard enough around Manassas, Warrenton and Fredericksburg for a light covering on grassy areas and elevated surfaces, but not roads. Radar indicates the steady activity commences in southern Fairfax county and extends through northern Prince William and Fauquier county and then continues south.

Elsewhere, to the north, the patchy snow is being described as “conversational”, “light snow flurries”, “heavy flurries”, “light snow” and “tiny snow flakes” among other descriptors.