Taste of April! 50s & 60s ahead; Signs of an early (and thundery?) spring

50s in southern Minnesota and probably the metro Tuesday!

8 days at or above 50 degrees in the next 2 weeks?

2.96″ GFS forecast precip next 16 days….all rain?

38 degrees average high for MSP Airport next weekend

60 degrees possible in southern MN Saturday?

67 degrees GFS forecast high for March 16th (a week from Friday)

+20 degrees vs. average next two weeks?

Warm spring outlook for Minnesota from NOAA’s Climate Prediction Center (CPC)

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Major League Warm Front!

Warm air is gushing into Minnesota on gusty south winds as we speak.

Temps pushed 70 degrees in western Nebraska Monday, with 60s in the Dakotas. Bank thermometers flashed 65 in Rapid City Monday afternoon!

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The early (meteorological) spring warmth peak Tuesday over Minnesota. Temps should push 50+ degrees in most of southern Minnesota, with widespread 40s in the north.

A cool front brings us closer to reality Wednesday & Thursday…but not for long.

Southerly winds will blow again by Friday, and temps will begin to soar a good 15 degrees above seasonal values again.

“Meltmageddon”

Southerly winds, sunshine and warm temps are gong to do number on snow cover this week. One surprising factor in how quickly we lose snow cover is overnight temperatures.

Warm days in the 40s and 50s and stronger March sun eat a lot of snow during the day. But when overnight lows can stay near and above freezing, the sheer number of hours of snowmelt starts to add up.

There’s an “official” 2″ of snow on the ground at MSP Airport Monday. But here at the weather lab in the west metro it’s more like 4″ to 5″ “in the woods.” The north metro is still sporting 6″+ in some areas.

It may take a few days but it looks like most of the snow in metro and southern Minnesota will be history by Friday afternoon.

Saturday Temp Surge?

With most of the snow gone, strong sun and warm south winds may turbo boost temps Saturday.

50 looks like a lock again by Saturday afternoon, and I wouldn’t be shocked to see some 60 degrees temps south of (and maybe in) the metro Saturday.

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Sunday: “April Showers” in March?

The latest GFS is spinning up an unseasonably mild low pressure system from the Gulf of Mexico and sending it north toward Minnesota Sunday.

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Most years we’d be sounding early alarm bells about another possible “Tournament weekend Snowpacolypse”…but not this year. The models are solidly indicating it will be warm enough for all rain so far with this one….not even close.

Normally we’d be looking for temps at around 5,000 feet up (850mb) to be near 0C and tracing the infamous “rain/snow line.” Sunday’s 850mb temps look to run between +5C and +8C, and that means all rain.

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Sunday GFS numbers above: Box shows rain totals. Oval shows Celsius temps at 850mb (around 5,000 feet)

NOAA’s CPC: Warm March & warm spring?

The newest outlooks from NOAA’s CPC favor much above temps for Minnesota the rest of March…and probably a warmer than average spring through May!

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Looking at the maps I tend to agree. I think we’ll see an abundance of “green shoots” in March this year. Is it possible to see ice free lakes in southern Minnesota and lawns greening up by the end of March? Daffodils in March? I wouldn’t rule it out this crazy weather year.

Speaking of ice free lakes…here’s a great post from the MN Climate Working Group on just how lake ice melts this time of year.

How Lake Ice Melts

“1.In the late fall, the lake loses heat to the atmosphere, and then on a day or night when the wind is not blowing, ice forms. The ice gets thicker as long as the lake can continue to lose heat.

2.In most Januaries and Februaries, snow both reflects sunlight and insulates the lake. With a thick snow layer, the lake neither gains nor loses heat. The bottom sediment is actually heating the lake water slightly over the winter, from stored summer heat.

3.Around March, as the air warms and the sun gets more intense, the snow melts, allowing light to penetrate the ice. Because the ice acts like the glass in a greenhouse, the water beneath it begins to warm, and the ice begins to melt FROM THE BOTTOM.

4.When the ice thickness erodes to between 4 and 12 inches, it transforms into long vertical crystals called “candles.” These conduct light even better, so the ice starts to look black, because it is not reflecting much sunlight.

5.Warming continues because the light energy is being transferred to the water below the ice. Meltwater fills in between the crystals, which begin breaking apart. The surface appears grayish as the ice reflects a bit more light than before.

6.The wind comes up, and breaks the surface apart. The candles will often be blown to one side of the lake, making a tinkling sound as they knock against one another, and piling up on the shore. In hours, a sparkling blue lake, once again!”

Wet & thundery too?

There are also signs our wet pattern may continue for the next few weeks. This could mean some early bouts of spring thunderstorms…and possibly even some (gulp) severe weather… in March!

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Stay tuned!

PH

  • Bill

    Interesting to hear the detailed process by which lake ice melts!