Weather! Welcome to Winter

Winter begins tonight at 12:30am, but it doesn’t feel much like it. Mild, wet weather is going to be the norm for a few more days.

December 21, 2011; 12:52 PM • by Weather Dan

Winter officially begins tonight at 12:30am, and our weather will be anything but seasonable. Our average high and low for December 21 are 49 and 30. Yesterday, we hit 55 and 42. Today, we hit 49 around midnight, and are already at 59.

The blame for this lies with a very warm atmosphere, thanks to a feature called the North Atlantic Oscillation. The NAO is one of the primary determinants of winter climate for the east coast of the US, and is determined using the strength of the subtropical high pressure over the Atlantic and a low pressure area over Iceland. When the NAO is strongly positive, as it has been since mid-October, we generally stay mild. When the NAO is negative, as it has been for the better part of the two winters previous, we get more cold air, and as you’ve seen, the potential for plenty of snow.

Speaking of winter, the City of Richmond’s Office of Emergency Management has put together a video called “Emergency Management 101.”

Take a few minutes and go through this; there’s plenty of great info, including how to prepare an emergency kit and a plan in case bad weather or another emergency strikes, and how to stay informed during and after an emergency.

Right now, the only bad weather we’re concerned about is rain. There’s plenty of light rain across Virginia; off and on showers will continue through the better part of the day. An area of heavier rain is located along the western slopes of the Allegheny Mountains. It’s slowly working its way east, and will be well into Virginia later this evening.

Wednesday: We’re going to make it into the low 60s this afternoon, though cloudcover may keep temperatures from going much higher. If we get some breaks and a little extra heat, we might see 65 before things cool off this afternoon. The cloudcover and rain keep temperatures warm tonight, with lows near 55. Fog will be a concern overnight and into the early morning, so please be careful.

Thursday: We warm up again, making it two days in a row with highs in the low 60s. However, the cooling trend begins in the afternoon as the cold front responsible for all this rain pushes through, and temperatures drop into the low 50s by Friday morning. Thanks to all the moisture in the air and on the ground, fog will again be an issue overnight and into early Friday.

Friday:The next round of precipitation moves in Thursday night and Friday morning, giving us another good soaking before clearing out in the afternoon. Temperatures bottom out behind the front as we see some clearing of the clouds and temperatures dropping from an early afternoon high in the mid 50s all the way into the upper 30s by Saturday morning.

Skies look to stay partly to mostly cloudy on Saturday, with similar temperatures to Friday. Another batch of rain moves in on Sunday and into Monday morning, with highs both days only in the upper 40s. If you’ve got travel plans, especially to the northeast, keep an eye out as they may see some flakes out of this system. However, our Christmas, along with most of Virginia, is looking like it’s going to be quite wet and not white at all. I know the snow lovers out there are anxious to see a real measurable snowfall, but it’s not happening just yet. I’m still waiting on some signs that we switch to a colder pattern for January, but I don’t seem to be finding them. In the meantime, enjoy the mild weather.

Happy holidays, everyone!

December 21, 2011 12:52 PM 0