Week of February 20th GFS hinting at possible snow systems for Minnesota
1.51″ GFS liquid output for MSP week of Feb 20th
14.9″ season snowfall so far at MSP
16.5″ average snowfall for the remainder of the snow season at MSP
96.2% of Minnesota now in “moderate” to “severe” drought!
March snowfall potential critical for easing “hydrologic” drought
April rainfall potential critical for easing “agricultural” drought
Snowy pattern change ahead?
It’s too early to be definitive on this, but there are some encouraging signs for Minnesotans who want snow. Our desert dry winter doldrums may be about the end.
The upper air pattern is showing signs of becoming more “chaotic” in the next two weeks. Translation? We may finally get some snow storms passing in or near Minnesota.
Much of the USA has been mired in a persistent west-northwest upper air flow pattern this winter. This has brought mild air, and also little moisture.
The GFS model is advertising a more west-southwest flow starting the week of February 20th. This could steer a series of Pacific storms into the Midwest, and some of them may actually dip into the southern Plains and gulp down some significant moisture before dumping it as snowfall on Minnesota.
GFS hints at a possible “Panhandle Hook” snow storm around February 21st?
While it’s still way too early to credibly support these numbers, The 12Z GFS cranked out 1.5″ of “liquid” precip the week of February 20th from 2 different storm systems. If that verified and fell as all snow, it could add up to 10″ to 15″+ somewhere in Minnesota that week.
We’ll see. Trying to credibly nail storm systems that far in advance is futile. But the take away is this; The overall upper air pattern is changing and there could be a growing chance of snowfall the week of February 20th.
2012: Year of the Texas-sized “mega-drought” in Minnesota?
As we look ahead toward spring, Minnesota’s growing drought looms as the biggest weather story and concern of 2012.
A full 96.2% of Minnesota is classified in “moderate” or “severe” drought in this week’s U.S. Drought Monitor.
The water tap shut off late last summer in Minnesota, and last fall was the driest on record for many locations. Soils heading into the freeze were powder dry, and will remain that way into the spring thaw.
Weather patterns the rest of this winter into this spring will be critical in determining if this will become one of the worst droughts in Minnesota history, or a significant drought that is eased by above average spring precipitation.
Here are the variable at play the next 3 months.
Late February & March:
The second half of February and the month of March may determine how critical Minnesota’s “hydrologic” drought is going into the summer of 2012.
We’re living through the 2nd lowest snowfall season to date for much of southern Minnesota. Snowfall at MSP Airport is only 14.9″ so far, that’s a good month in most years and a good storm last year!
Northern Minnesota has seen better snowfall totals, but most areas are still way below average for the season.
The average snowfall for the remainder of the snow season is 16.5″ in the metro and southern Minnesota. We’ll need average to much above average snowfall between now and April to provide enough snow melt runoff to feed Minnesota’s rivers & lakes, which are at very low levels.
This runoff is critical for easing the “hydrologic” component of drought (rivers, ponds, lakes etc.) but doesn’t help much with the “agricultural” or “soils” component since the ground is still frozen and most runoff from snow melt won’t soak in.
That’s where April weather comes in to play.
April & May:
Average rainfall for April is about 2.3″ for the Twin Cities and southern Minnesota. We will need every drop this spring and significantly more if we are going to stave off a major drought in 2012.
The ground thaws in April. April rainfall soaks into soils, and will recharge them for the growing season. We’ll need above average rainfall in April & May to ease drought conditions in Minnesota. Average rainfall won’t do this year. A good 4″ to 8″ of spring rains is what we need to prevent serious drought as we head into the summer of 2012.
Will fading La Nina help?
CPC is out today with news that La Nina is close to being history in the tropical Pacific.
This could possibly be good news for a wetter spring in Minnesota. If “ENSO neutral” conditions evolve we could see a return to more “normal” spring weather patterns in the Midwest.
At this point (in a drought) any pattern change is likely to lead to wetter conditions.
Weather fingers & toes crossed on that one.
Arctic air pushes south:
A few flurries may accompany the arctic front surging south into early Friday. Get ready for a bracing day Friday, with wind chills at or below zero in most of Minnesota!
Chicago lake effect snow blitz Friday!
As arctic air hits the still relatively warm waters of Lake Michigan, a rare lake effect snow burst will hit the Windy City and northwest Indiana Friday into Saturday.
While lake effect is common in northwest Indianan and Michigan, low level wind trajectories have to be just right to get lake effect snow in Chicago. Friday into early Saturday brings the perfect NNE wind trajectory that flows down the entire fetch of Lake Michigan and right into the Chicago metro area.
At least 6″ could fall in Chicago, and this set up look so good that I wouldn’t be shocked to see some bands of 6″ to 12″ in and close to Chicago.
At least somebody in the Midwest is getting snow Friday!