Friday, December 7, 2018  3:20 AM

A While Before Climbing Out of the Arctic Temperature Hole

Sub-Zero Earlier This Evening, But Few Clouds and Flurries Early AM

For the first time in nearly a month, St. Cloud temperatures fell back below zero last evening (see NWS: Last 72 hours of St. Cloud Observations) as clear skies and light winds were in the area. However, another batch of low clouds moved in around midnight (see Shortwave Albedo loop from Colorado State satellite slider menu). These clouds are associated with a weak, moisture-starved low pressure system that has been pushing southward in Saskatchewan and Manitoba overnight (see Mid-Tropospheric water vapor loop from Colorado State satellite slider menu). There are a few snow flurries not picked up well by radar, but in the reports from the airports near Lake of the Woods (see NWS Upper Mississippi Valley radar loop) and in other scattered areas (see UCAR Minnesota surface chart) this morning. Temperatures under the clouds have been bumped back above zero and even into the teens. The light southwest winds are producing some wind chills from zero to the plus single digits (see NWS Minnesota Hourly Weather Round-Up).

Sun Should Return, Warmth Will Not

The good news is that the cloud patch isn't that large, so I expect to see some midday and afternoon sunshine today after the low scoots to our east (see Shortwave Albedo loop from Colorado State satellite slider menu). Temperatures will again be limited to the 15-22 degree range.

Major Storm Tracks Across Southern US..

There isn't going to be a lot of change in our weather from now into early next week. The main storm track will continue across the southern US (see Mid-Tropospheric water vapor loop from Colorado State satellite slider menu), so the big weather-maker will be the southern California storm that will pull the really warm and sticky air over south Texas (see NWS WPC Latest North American zoom-in surface map) northward. There is a major heavy rain threat today in Texas into Louisiana and tomorrow in Mississippi, Alabama, and Georgia. This storm will continue to the Carolina coast on Sunday. The threat of frozen precipitation over the Southern Plains on the edge of our cold air seems to be reduced across the Texas panhandle today. There still could be some ice and snow in Arkansas tomorrow, but the main frozen threat will be the potential for a major Saturday night and Sunday snow in the interior of the Carolinas and Virginia. There also could be accumulating ice in this region.

...But We Remain Mostly Dry and Slightly Milder into Early Next Week

However, we will remain in the northern stream of flow. There are a couple of other low pressure systems in that northwest flow between the Yukon and the Prairie Provinces (see Pacific infrared satellite loop from University of Wisconsin/SSEC), but they are hard to see in the infrared loop since there is little moisture available to produce a large cloud area. Each of these systems could bring a few patches of clouds, but we will likely see a mixture of sun and clouds through the weekend. The best chance for clouds and perhaps some light snow or flurries will be on Sunday from eastern South Dakota into southwestern Minnesota. Light south to southwest winds will continue. We may have a shot at one more low near zero tonight, but lows will generally be in the 10-18 degree range from Saturday night into early next week. Highs will basically stay in the 17-24 degree range on Saturday, and climb to the middle 20's from Sunday into early next week.

Good Chance for Tuesday 40's....5,000 Feet Up

This northern stream will begin to produce a patch of warmer air in the lee of the Rockies in the Yukon and British Columbia tomorrow and this warmth will spread downwind of the Canadian Rockies through the weekend, then reach the Northern Plains early next week. The forecasts have delayed the warm push into the Dakotas and Minnesota for a couple of weak northern stream storms. However, the computers are consistent at showing temperatures in the 40's over Minnesota by Tuesday. Unfortunately, that's at 5000 feet above the ground. It may be difficult to get that air all the way to the ground through the leftover cold air, especially if we can climb above freezing and melt all of that snow to our south (see snow depth map from NWS NORHSC). That could add moisture and create a low cloud or fog layer. So, I'm not ready to forecast above freezing temperatures through Tuesday.

Confidence Level: "The Bulb on That Hard-To-Reach Light in the Foyer Will Burn Out"

Friday 12/7/2018: Lingering morning clouds with perhaps a flurry, then increasing sunshine. Light winds, but not quite as cold. High: between 15 and 22. Winds: SW 5-15 MPH. Chance of measurable snowfall: 10%.

Friday Night: Mostly clear, light winds, and continued cold. Low: near 0. Winds: W 5 MPH. Chance of measurable snowfall: 0%.

Saturday 12/8/2018: Partly sunny and still seasonably cold. High: between 18 and 24. Winds: S 5-10 MPH. Chance of measurable snowfall: 0%.

Confidence Level: "Every Time I Try to Put in a New Bulb, the Light Fixture Will Try to Detach From the Ceiling"

Saturday Night: Partly clear, a bit of a breeze, and not quite as cold. Low: between 10 and 15. Winds: SW 5-10 MPH. Chance of measurable snowfall: 10%.

Sunday 12/9/2018: Morning clouds, some afternoon sun, and seasonably cold. High: between 22 and 27. Winds: SW 5-15 MPH. Chance of measurable snowfall: 10%.

Confidence Level: "The Only Way I'll Be Able to Change the Bulb and Hold the Fixture in Place Will Be to Yell At It

Sunday Night: Partly clear and still cold. Maybe some fog by morning. Low: between 12 and 18. Winds: SW 5-10 MPH. Chance of measurable snowfall: 10%.

Monday 12/10/2018: Partly sunny, breezier, and seasonably cold. High: between 22 and 27. Winds: SW 8-15 MPH. Chance of measurable snowfall: 10%.

Monday Night: Continued chilly with perhaps some fog. Low: between 12 and 18. Winds: SW 5-10 MPH. Chance of measurable snowfall: 10%.

Tuesday 12/11/2018: Some sunshine through high clouds and a shade milder. High: between 25 and 30. Winds: S 5-15 MPH. Chance of measurable snowfall: 10%.

Extended: Average to above average temperatures most of next week.

Forecast Confidence (10 - "The Rabbits Will Thump, Objecting to Me Yelling at the Light Bulb"; 0 - "I Will Be Hosting a DIY Show on Home Repairs"): 6 Wednesday through Thursday night, 5 Friday and Friday night, 4 Saturday, 3 Saturday night, 2 Sunday.

Yesterday's High: 19°F (set at 1 AM Thursday); Yesterday's High: 17°F; Overnight Low (through 3 AM Friday): -1°F
St. Cloud Airport 24 Hour Precipitation (through 3 AM Fridayay): Trace; SCSU Precipitation (through 3 AM Friday): TBA

Next Update: Monday, December 10, 2018 8 AM (or as needed)

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Let me know what you think about this forecast and discussion by emailing SCSU meteorology professor Bob Weisman. Please note that I make the forecast, not the weather!

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