Updraft: March 3, 2010 Archive

Mild March may linger to mid month

Posted at 8:45 AM on March 3, 2010 by Paul Huttner (1 Comments)

We're off and running.

So far March is like a pent up thoroughbred exploding out of the gate. We're running about 4 degrees above average so far this month, and there's no sign we're looking back.

The Polar Front Jet Stream has lifted unusually far north this month. Usually we can count on a jet stream howling overhead in Minnesota in March, dealing us wind and storm after state tourney snowstorm. Not this year.

Polar Front Jet Stream lifts into central Canada. (Image courtesy University of Wisconsin)

The jet has lifted about 500 miles north of its typical March position. It looks like what should have been our classic El Nino jet stream pattern in the Upper Midwest this winter is finally taking firm hold in March. Maybe we'll get an early spring instead of the statistically likely but undelivered mild winter.

Look for the mild pattern to hold into mid-month. Anything after that gets pretty murky in the crystal weather ball. By then we should be a good 3 to 5 degrees above average and a milder and drier(less snowy) than average March seems like it will be in the bank.

Every other month?

Weather comes in not so predictable, chaotic cycles. I've observed that we're in a weird pattern since last July. Every other month has featured alternating dry and wet patterns in Minnesota. Check out the Twin Cities monthly precipitation totals compared to average since last July.

July -1.87"
August: +2.38"
September -2.23"
October +3.46"
November -1.56"
December +10" (snow)
January -10" (snow)
February + 6" (snow)

It's uncanny to get such clean, alternating monthly flip flops between wet and dry for 8 consecutive months. March looks like it will fit right in so far. I don't see any significant storms that will dump heavy precip on Minnesota for the first two weeks of March.

I really don't have a theory as to why this is happening. I've observed in the past that hot and cold weather patterns sometimes tend to hold for 4 to 6 weeks, but there are so many oceanic circulation patterns in effect in addition to El Nino cycles that it's almost impossible to overlay them to create one solution for monthly weather forecasts.

So far, this one falls under the category of "go figure."

Sun more active:

Sunspot region 1045 sends a coronal mass ejection (CME) into space

There's been a marked increase in the number of sunspots over the past couple of months. It looks like the deepest solar minimum in nearly a century is finally over, as new Solar Cycle 24 kicks in.

NASA image

Most of the research done on the solar component of climate forcing indicates that solar variability is a relatively small component of climate change. One might ask how the last two years were both in the top 10 warmest on record globally during a deep solar minimum. Clearly larger forces are at work, or you would expect that the planet would have cooled significantly if solar variability were the primary driver of climate on earth. Instead we have seen two of the ten warmest years on record.

Enjoy plenty of sun and another run into the 40s today through Friday.

PH

(1 Comments)

Favorable snowmelt for Minnesota rivers...so far.

Posted at 4:42 PM on March 3, 2010 by Paul Huttner

NOHRSC snow depth analysis shows over 20" of snow in western Minnesota. Snow cover is down to under 4" in some areas of east central Minnesota.

This is how they write it up in the Hydrologist offices at NWS in Chanhassen. Nice and slow.

Our current weather pattern with days in the lower 40s and nights below freezing is just about right for slowly releasing water from our snowpack into area rivers and streams. That's doesn't mean there won't be any flooding this spring, but it may prevent a potential huge spike in river levels that would occur with a rapid warm up into the 50s and or a heavy early spring rain on snowpack.

I talked briefly with Tony Zaleski at NWS in Chanhassen today; and he seems pretty pleased with the current rate of melt. In his ideal world, he might ask for another 2 to 4 degrees in the afternoons, boosting temps into the mid 40s, but the current daily diurnal temperature variation is just about ideal.

My view of the maps for the next few days continues the nearly ideal weather pattern for slow steady snow melt. The idea is to let some loose during the day, and then lock it down at night with sub freezing temps. This slow release keeps rivers from spiking out of control.

Forecasts still call for a good chance of major flooding on the Minnesota and Red Rivers, but signs are good for flood weary river towns in the Upper Midwest at this point.

Pine tree effect visible from space:

Check out today's Minnesota 1km visible satellite image below. You can clearly see the darker shades from space in eastern Minnesota and northern Wisconsin.

College of DuPage GOES 1km visible satellite image.

These are the darker coniferous and hardwood forests soaking up sunlight and turning it into long wave radiation that warms the air more efficiently. The whiter areas in western Minnesota and the eastern Dakotas show the more "reflective" prairie biome, and a few clouds today. That's why it's anywhere from 5 to 10 degrees warmer in eastern Minnesota these days.

Enjoy two more days of patchy morning fog from snowmelt, and sunny afternoons in the 40s before a few more clouds roll or way Saturday.

PH