Posted at 6:34 AM on December 7, 2011
by Craig Edwards
Filed under: Winter 2011-12
Another cold front is poised to swing through Minnesota in the next twenty-fours. It appears that morning temperatures on Friday will likely be sub zero in many locations. Surprisingly, the coldest temperatures, due in part to the lighter surface winds, might be observered in southeast Minnesota, where a couple inches of snow remain.
Here's the NAM for surface temperatures and winds at 6AM on Friday. See the temperature forecast of around eight below zero around Mankato.
The rainy weather in the Ohio Valley, that resulted in both daily and annual precipitation records in Louisville, has moved east. Sigificant precipitation is expected in the densely populated region from Washington D.C. to Boston.
Here is the liquid content of the moisture expected in the next 24 hours.
Mostly rain is expected from Balitmore to New York City and on up to Boston.
National Weather Service graphic for watches and warnings.
Detailed forecasts can be captured at weather.gov
If you have air travel during the course of the winter season you may wish to bookmark this website from the FAA.
For our neck of the woods, we can expect a cold Thursday and Friday with moderating temperatures for Saturday and Sunday. Temperatures are likely to climb above the thawing point on Sunday afternoon.
Yesterday was the coldest day in the Twin Cities since March 2nd. The daily average was only 15 degrees, with the minimum dropping to 10 degrees at the International Airport. So far we have not had a reading in the single digits at the Airport this season. Let's see what Friday morning brings.
From the Chanhassen NWS.
The sun is setting low on the southwest horizon these chilly winter afternoons. In the Twin Cities the earliest sunset of 432PM commenced on December 3rd. On the 17th of December you will barely notice the sunset a minute later at 433PM.
Due to the tilt of the earth on its axis and the elliptical trip around the sun, we continue to lose daylight in the morning hours. Sunrise on this date is 737AM in Minneapolis. The latest sunrise will be 751AM beginning December 30th and continuing until January 6th. The shortest daylight occurs on the solstice(1130PM) on December 21st.
Did you also happen to notice the micro-climate in the photo at the base of the evergreen tree? Sunshine captured by the green pine needles reflects back the heat and allows for melting of the snow.
This absorption of heat is evident in the late winter and spring on a larger scale in the Superior National Forest. Sunshine captured by the trees can efficiently warm the lower atmosphere more than the sun's rays reflecting off the snow covered prairie landscape.
Some locations in Minnesota saw the thermometer climb to near 32 degrees this afternoon. I'm thinking part of this nice rise in temperatures is due to the lack of snow cover in western Minnesota as well as in the upstream source region of cold Canadian air.
A colleague with the National Weather Service was in Winnipeg last week and noted the sparse snow cover when flying over the region. At this time of the season a thick snow cover keeps the air mass icy as it travels the mid latitudes. The magnitude of the cold can be modified if moving over bare soil.
A brisk west to northwest wind on Thursday afternoon, particularly in northern Minnesota, will create some numbing wind chill readings. As the winds diminish on Thursday night look for temperatures to drop steadily to below zero in many locations.
Milder temperatures for the season are expected Sunday and Monday.
Precipitation was slowing air and auto travel on the East Coast. Heavy rain today has drenched the landscape from Washington D.C., through Baltimore to New York City.
A snap shot of the radar from late afternoon in theD.C. area.
I am not spying a significant snow in the upper Midwest on the most recent computer models, but that has been known to change. Perhaps Paul will have been luck stirring up some snow when he returns.