Cold and dry arctic air in place through Friday

Posted at 2:14 PM, Dec 15, 2016
and last updated 2016-12-15 14:14:50-05

RICHMOND, Va. -- A strong cold front passed through Virginia early Thursday morning.  Temperatures dropped from the 40s before daybreak down through the 30s the rest of the morning.  Gusty northwesterly winds will keep wind chills in the teens and 20s.  Wind speeds will decrease overnight.

Lows Friday morning will drop into the single digits and teens.


Highs Friday afternoon will stay in the lower 30s.


This will be the coldest weather since Valentine's Day.


The arctic air cannot hold much moisture, so it is very dry.  When you bring that air inside your home and heat it up, the indoor relative humidity becomes very low.  If you have your heat set around 70°, the indoor humidity will only 5%.  Running a humidifier will make the heat feel warmer, and also eliminate static electricity and the dry feeling on your skin and in your sinuses.  You typically want the indoor humidity to be roughly half the temperature, so having the humidity around 35% will work well.


Warmer air will push northward through the state Saturday.  It will be cold enough Saturday morning for some wintry precipitation.


A storm system will spread moisture into the region late Friday night into daybreak Saturday.  The precipitation will transition quickly from snow to sleet to freezing rain.  Temps rise above freezing by mid-morning.  Areas well south and east will see a little ice but mostly rain.  Areas north and west of Richmond will hang onto a wintry mix until late morning or midday.  Far northern and western Virginia will keep the wintry mix into early afternoon.  Precipitation amounts will be light in the metro, but some slick spots will be possible, primarily on elevated surfaces.  There is a better chance of a very light dusting or glaze on untreated surfaces north and west of Richmond.  The heaviest precipitation will fall in far northern and western Virginia, where travel may become icy into early afternoon.