Updates: Snow varies in intensity with additional accumulation possible; some roads improving

Dan Stillman

Meteorologist and editor of the Capital Weather Gang

January 13th at 10:45 am

Winter storm warning for the whole territory until midnight | Reports on Snow Totals *

Overview

• As a general rule, we observed 4 to 7 inches of snow since the accumulation that actually began to occur. Accumulate last night, increasing amounts from north to south. The snow, combined with temperatures in the mid-twenties, left many side roads impassable and snow-covered. But the main roads are beginning to improve.
• It is possible that there are 2 to 4 inches left in the rest of the day. Total thunderstorms of about 5 to 10 inches are likely in the evening as amounts increase from north to south. Some localized locations, mainly in southern British Columbia, could see up to about 12 inches.
• Fortunately, it's a Sunday; so many of us can sit and enjoy the winter landscape. For those who need or want to go out, the travel conditions should be better by the afternoon, as the road crews try to catch up, and that daylight helps to make melt snow and slippery spots on the treated pavement.
• That said, after a lull at noon, the snow could resume from mid-afternoon to early evening and we expect many cancellations tomorrow.

10:45 am – Some roads improve as snow varies in intensity

Snow is generally clear and scattered throughout the area and is expected to extend well into the early afternoon with only small accumulations. during this period. Model data suggest that snow may become more stable around 14 hours. for a few hours, especially from the city center to the south and southeast points. The lighter snow allowed for improved travel on treated roads with many lightly wet roads or some slush, although many secondary roads remain covered with sow if they have not been plowed recently. If you go out, always drive with great caution, especially during periods of more stable snow.

9:30 – More photos while the snow breaks

While the snow breaks a bit inside and around the Beltway, we expect the situation to varies from one spottier to another lighter to sometimes sometimes more stable and heavier throughout the day – now is the time to look at some extra photos of our first snow of 2019! … …

8:30 am – Even more snow?

It's time to look at what is considered the best model for short-term forecasts up to about 12 hours – the NOAA High Resolution Rapid Regeneration (HRRR) model. Below, the simulated model radar from 8:00 to 22:00. aujourd & # 39; hui. As the depression continues to develop off the Virginia-North Carolina coast, the model attempts to maintain precipitation over the DMV all day and evening, although the pattern tends to be less effective over the course of the day. beyond about eight hours. Since the immediate area of ​​the distribution center is towards the northern limit of the system, there is some uncertainty as to the lightness or intensity of the snow, hence an additional snow fork. 3 to 6 inches from what we had last night and during the night. , the southern areas have the best chance of reaching the upper limit of the beach.

Radar simulation by HRRR model from 8 to 22 hours. aujourd & # 39; hui. (StormVistaWxModels.com)

7:20 – Last snow totals

These last snow totals from National Weather Service indicates that the total mass has dropped from 3 to 6 inches in the region, with smaller amounts being blended. Some reports are a few hours old, but overall, this is representative of the snow we have seen so far.

(National Weather Service)

6h50 – Winter wonderland in the DMV!

Alright, after this last update a little fishy, ​​it is now time to take a picture! … …

6:15 AM – Stronger group Possibility of early morning snow south of DC

Earlier this morning, the National Meteorological Service's Storm Prediction Center highlighted an area including DC, the northern Virginia and southern Maryland for the risk of moderate to heavy snowfall about 1 inch per hour during the 6 to 10 hour period (see chart below). This is due to a jet stream – a part of the jet stream that moves very rapidly in the heights of the atmosphere – which can induce an extra "lift" in the atmosphere and therefore a thicker snow . A fast snow of 2 to 3 inches of snow is possible if and where this heavier snowpack develops, which seems more likely for the southern half of this area, but could affect an area as far north as the southern suburbs. DC.

(1965) NOAA's Storm Prediction Center)

See Current Weather Conditions at the Washington Post Headquarters

Follow us on Facebook and ] Instagram . for the latest updates. For traffic news, see Gridlock . Continue reading for the forecast until the end of the week …

Tomorrow (Monday): A few light flurries may persist early before the sun rises, but It will take some time to melt our snowpack, as a fresh breath of air limits the tops to 30-30. Nevertheless, a partially sunny sky should help melt the muddy areas of the roads around noon. The winds remain light and out of the north. Confidence: Medium-High

Tomorrow night: The heavens continue to clear progressively in the evening and into the night, allowing temperatures to plunge into low or mid-range -around twenty. Wet areas that developed under the afternoon sun may freeze again, so watch out for slippery areas that begin. Confidence: Medium to high

Accumulation of snow in Rockville last night. (George Jiang via Flickr)