Issued at 3:44 PM CST, Thursday, January 15th, 2009
Surface Analysis at 21z:
Arctic ridge of high pressure averaging 1044-1046 mb or 30.70″-30.81″ had two centers with one over far Northeast Nebraska and the other over Southern Kansas. A stationary front extended from Central Alberta Province to Central Wyoming down to Eastern New Mexico.
Upper Air Analysis at 21z:
500 mb ridge covered areas west of the Rockies with the center of the upper level high just offshore of California. 850 mb temperatures underneath this ridge ranged from +10 to +16 degrees C This Afternoon with surface temps in the 60s, 70s, and even some 80s from Oregon through California down into Arizona. Minnesota remains well to the east of this upper ridge with arctic air remaining in place with 850 mb temps This Afternoon ranging from -24 to -26 degrees C over Northern and Eastern Minnesota to -20 degrees C in Southwest and far Western Minnesota.
Sunny skies covered Minnesota Today with another day of arctic air with bitterly cold wind chills. High temps Today were mostly in the single digits, teens, to around 20 below zero with just a few locales rising to zero or slightly above zero during the Afternoon. Winds across the state were out of the southwest, west, or northwest around 10-20 mph. Afternoon wind chills around the state were in the teens, 20s, and 30s below zero.
Some temperatures around Minnesota at 3 PM CT ranged from -18 degrees at Thief River Falls to -4 degrees at Cook to -19 degrees at Elbow Lake to -2 degrees at Little Falls to zero at Cloquet to -10 degrees at Olivia to -8 degrees at Owatonna.
Tonight and Friday:
*Wind Chill Warning* remains in effect for Northern, Central, Eastern, and Southern Minnesota through Noon CST Friday.
Arctic high pressure will be pushing off to the southeast of Minnesota during this period. Weak warm advection is already occurring over most of Minnesota late Today but this hasn’t caused surface temps to get out of the frigid territory quite yet. Another night of icy cold air will remain in place across Minnesota Tonight with lows ranging from around 10 below to 25 below with 25 below to 45 below temps expected one more night over parts of Northern, Northeast, and Central Minnesota. Winds Tonight will be out of the west, southwest, or northwest around 20 mph or less which combined with the bitter cold temps will cause wind chills to drop into the 30 below to 55 below range for areas that are in the wind chill warning through Friday Morning. By Friday, look for warm advection to become somewhat stronger in Minnesota as southerly winds pick up on the back side of the arctic high to our southeast and out ahead of a pretty strong low pressure system which was up in the Northwest Territories late This Afternoon. High temps on Friday will range from around 10 below to 15 to around 20 above with the warmest temps out in Western areas of the state. South or southwest winds are expected at 10 to 25 mph. Look for clear to mostly clear skies over Minnesota Tonight with partly to mostly cloudy skies on Friday. May start to see some flurries develop as well by Friday over parts of Minnesota out ahead of the low approaching from Northwestern Canada.
Friday Night:
A Manitoba Mauler will be swinging SE into Minnesota, this system will bring some snow to Northern and Eastern parts of the state with flurries or perhaps even a bit of light freezing drizzle for the rest of the state. Snow accumulations of 1 to around 3 inches are possible over Northern and Eastern Minnesota Tomorrow Night with the higher totals found along the North Shore of Lake Superior where SE winds at the surface coming off Lake Superior could lead to some lake enhanced snowfall from Two Harbors on up toward the Grand Marais area. Snow to liquid ratios look to be in the 20:1 to 30:1 range Tomorrow Night with a period of favorable dendritic growth zone passing NW-S/SE through Northeastern Minnesota. Basically what this means is that the snow Tomorrow Night will be quite fluffy with just a few hundreths inch of liquid precip resulting in up to 2 or 3 inches of snow. Look for mostly cloudy skies around the state Friday Night with low temperatures holding steady or slowly rising from around 5 below to 15 above. Winds Tomorrow Night will be out of the west, northwest, south, or east around 20 mph or less.
Extended Forecast:
Amplified N-NW flow aloft will be in place around Minnesota this weekend into early next week while the upper level ridge of high pressure over the Western U.S. tries to nudge east into Minnesota toward the early or mid part of next week. Temperatures will be warmer across all of Minnesota this weekend through the middle of next week, but that won’t take much considering how cold it’s been as of late. A couple of weak disturbances will likely drop S-SE toward our area into early next week with some light snow showers or flurries possible as those systems pass through. High temperatures around Minnesota will be in the teens, 20s, and 30s Saturday and Sunday with lows Saturday Night and Sunday Night ranging from around 10 below to the single digits and teens above zero. Looking farther out toward later next week and next weekend shows another blast of arctic air possibly affecting the Upper Midwest, although it’s still too early to say how long this possible arctic blast will last and also how cold it’ll actually be. A couple GFS model runs over the last few days bring 850 mb temps down to around -25 to -32 degrees C again around Minnesota, but then a few other runs show slightly milder temps. It seems pretty certain that it will be turning cold again later next week-next weekend, just how cold is in question at this time.
Forecast for Duluth/Superior:
*Wind Chill Warning* in effect until 12 PM CST Friday…
.Tonight… Bitter cold with dangerous wind chills. Clear. Low 18 below to 26 below. Wind west to northwest around 20 mph. Wind chills from 30 below to 50 below.
.Friday… Partly to mostly sunny. Dangerous wind chills before Noon. High 2 below to 6 above. Wind southwest at 10 to 20 mph. Morning wind chills from 30 below to 50 below.
.Friday Night… Some snow developing. Accumulations of one to two inches possible. Temperatures holding steady from around 2 below to 6 above. Wind south to southeast around 15 mph.
.Saturday… Light snow or flurries possible in the Morning with lingering flurries in the Afternoon. Little additional accumulation expected. Considerable cloudiness. High 15 to 23.
.Saturday Night… Partly to mostly cloudy. Low zero to 5 above.
.Sunday… Flurries possible. High 17 to 24.
.Sunday Night… Flurries possible. Low 5 to 10.
Normal High Temperature Tomorrow 17 degrees
Normal Low Temperature Tomorrow -2 degrees
4 PM Thompson Hill Observation:
Current Temperature: Zero degrees
Dewpoint: -17 degrees
Humidity: 42%
Wind: W at 8 mph G 16 mph
Max Temperature Today: 0.7 degrees
Max Humidity Today: 79%
Min Temperature Today: -23.6 degrees
Min Humidity Today: 42%
Tim