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* Winter Storm Warning through 11 p.m. | Wind Chill Advisory tonight thru Wed. noon | Local closings | The Grid (images from around town) | Reader photo compilation | Latest snow amounts from NWS | Detailed forecast through the weekend | More Post storm coverage *

Basic information

• What are the expected snow totals? 4-7″ for immediate metro area (closer to 4″ downtown), 6-10″ for northern suburbs (Frederick, northern Montgomery, Loudoun and Howard counties), 2-4″ for southern suburbs (Prince William, southern Fauquier, Charles, Stafford, St. Mary’s counties)
• When will it be the worst?  The heaviest snow is over for the most part
• When will it end? Between 9 p.m. and midnight, from west to east.

Forecast update

Snow is starting to taper off in our far western suburbs, especially in western Loudoun and Frederick counties.Along and east of I-95, steady snow continues, but will gradually shift east and diminish over the next couple hours. Little additional accumulation is expected west of I-95, with an additional coating to an inch elsewhere. Due to the moderate band that pushed through the region this evening, snowfall totals in the region have mostly reached forecast levels, even south of town towards Fredericksburg on the low-end.

Once the snow ends, the big story is going to be the combination of cold and wind. A wind chill advisory is in effect and continues through noon Wednesday. Wind chills Wednesday morning will range from -5 to -15. Actual air temperatures will be in the single digits.

HRRR model simulation of wind chills at 7 a.m. Wednesday (WeatherBell.com)

During the day Wednesday, it is going to be extremely cold, with highs only 10 to 15 and wind chills, throughout the day, struggling to rise above zero. It may become just the 4th day in the last 30 years with highs only in the teens at Reagan National.

For the outlook through the weekend, see Matt Rogers’ forecast…

Our latest Twitter updates

SchoolCast

3.5 apples: Most school systems will close or have closed already due to today’s snow and tomorrow’s frigid cold. It’s possible (25 percent chance) D.C., Alexandria and/or Arlington schools might try to open, but I’d imagine they’d delay a couple hours at least.

FedCast

3 domes: I think OPM will open government, but with unscheduled leave and telework options; a delayed arrival isn’t out of the question