Wind, warmer, rain, snow and a quiet US tornado year so far

Rapid fire weather changes. That's the forecast in a nutshell the next few days.

Surprised?

Nope. This is March in Minnesota after all.

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Wednesday winds

You'll notice the wind Wednesday. At first it will feel like the same cold wind we've enjoyed all winter and early spring. But by later afternoon the breeze grows milder. A warm front cutting into southern Minnesota marks the advance of milder air as winds blow from the south for  change.

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NOAA/National Digital Forecast Database

Temperatures soar into the 50s in southwest Minnesota, and a snow melting breeze with temperatures in the lower 40s are looking more likely for the Twin Cities metro area by about 4 p.m. Wednesday. Northern Minnesota warms up into the 30s. The dividing line between winter and spring? Close to the metro by afternoon.

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NOAA

Thursday rain/snow mix for Minnesota

The latest track and temperature trends with Thursday's weather system continue to favor more rain than snow for the metro, with better chances for plowable accumulation in Northeast Minnesota and possibly a snowy stripe in the southeast.

Here's the latest surface map from the National Digital Forecast Database, which favors rain for the metro most of Thursday, before a potential change over to wet snow late in the day.

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NOAA/National Digital Forecast Database

The best chances for accumulations favor northeast Minnesota and northwest Wisconsin. Here's the view from the Duluth office of the National Weather Service.

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The changeover from rain to snow, and a second burst of moisture may favor southeast Minnesota. The La Crosse NWS weighs in.

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Overall I am still leaning toward mostly rain for the metro Thursday, with a possible change to a couple hours of wet slushy snow late in the day. With temps at or above freezing it could to be tough to get significant accumulations in the metro. Any track changes Wednesday could change this forecast, so stay tuned as we tweak things before Thursday's system arrives.

Rain: The great snow eater

The latest snow depth maps shows southwest Minnesota is mainly snow free, or has very little snow. Most of that will be gone by Wednesday evening as warmer snow eating winds push temperatures to 50 degrees.

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Image: NOAA

With temperatures forecast to rise (well) above freezing the next few days, we're going to start working on removing the snow cover in the metro and central Minnesota once again. But the biggest snow eater this time of year?

Rain.

Nothing attacks a snow cover in late March like a soaking rain. Most models crank out about a quarter of an inch of rainfall Thursday if the system rolls in as warm as expected. That should go a long way toward weakening the snow cover that's left. Throw in weekend temps in the 40s and 50s, and things may look very different around the metro by late Sunday afternoon. The process we call '"spring" is slow this year in Minnesota. But small changes like rain instead of snow and bare ground getting closer can have a big impact.

Do I still have a lawn under there?

Warmer weekend still on tap

All signs are still go for much warmer temps and rapidly melting snow this weekend. The Global Forecast System and European models still differ on exactly how mild we'll get Sunday, but both push temperatures well into the 50s and challenge the warmest day of the year so far.

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Weatherspark

The Euro has come back to reality a little bit with a high of 59 Sunday.

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Weatherspark

Either way, this looks like the best weekend of 2014 so far!

Silver linings: Chilly spring means fewer tornadoes

Want some good news from our chilly spring so far? Fewer tornadoes in the United States. Colder air deep into the south means the atmosphere is just not able to generate big tornadic supercell thunderstorms. At least not yet.

The numbers so far show a preliminary tally of just 48 tornadoes in the United States so far this year, well below the three-year average of 82 to this point.

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NOAA/SPC

The reason? Just not enough instability in the atmosphere. Here's a look ta the cumulative Convective Available Potential Energy (CAPE) so far compared to average.

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NOAA/CPC

The slow season means usually busy NWS offices in Tornado Alley are unusually quiet this year.

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As warmer air moves north, conditions can change rapidly, and big tornado outbreak are certainly possible this spring. I have a feeling tornado activity will ramp up dramatically in the central United States in the next few weeks. The most likely day of the year for a tornado in your town? How about June 3?

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NOAA/CPC

Here's a good read on the slow start to the tornado season from Climate Central's Brian Kahn.

At least there's one benefit to our chilly early springtime.