Thursday, March 31, 2011

Looking ahead to April

As March comes to a conclusion, most Minnesotans are left wondering, “what happened to spring?”  This is the 5th snowiest winter season on record with 84.7 inches of snow, and we may add to that in April.  Since the first official day of spring on March 20th, high temperatures have been in the 30’s and 40’s.  If there’s a bright side, it’s that temperatures should begin to climb now that the sun’s angle is increasing.  The average temperature for April is 46.2 degrees.  The bad news: The Climate Prediction Center (CPC) is indicating temperatures will be below normal across much of the Upper Midwest through the month.


The cold spring weather can be attributed to the weakening La Nina pattern in the Pacific, as discussed by the CPC:

La Niña will continue to have global impacts even as the episode weakens through the Northern Hemisphere Spring. Expected La Niña impacts during March-May 2011 include suppressed convection over the west-central tropical Pacific Ocean, and enhanced convection over Indonesia. Potential impacts in the United States include an enhanced chance of below-average precipitation across much of the southern states and the Central Rockies and Central Plains. An increased chance of below-average temperatures is predicted for much of the West Coast and across the northern tier of states (excluding New England). A higher possibility of above-average temperatures is favored for much of the southern half of the contiguous U.S.

The trend is also for a wetter April, which could translate to an overall rainy spring.  This will not help elevate the flooding situation across many of the rivers in the Northern Plains.  Rivers across southern Minnesota experienced a first crest this week, with a second crest expected in mid-to-late April.  Here’s a look at the Minnesota River in Shakopee, where high water levels are being forecasted for the middle of the month:


As for the short term, a potent storm system will move across the northern tier states Sunday into Monday.  The models seem to be indicating that most of the precipitation will fall as rain with maybe a few wet flakes mixed in at times.  The pink line on the map below represents a rough snow/rain line:


As much as an inch of precipitation may be seen from this early week storm.


If this December or January, we could easily be looking at a foot or more of snow. Thankfully, we are past that! I don’t think we’ll be seeing 14 inches of snow to break the all-time snow record. Hopefully, we don’t see periods of heavy rains to accelerate river levels.  Rain is worse than snow for the flooding situation.  While I’m not anticipating a warm and dry spring, I encourage everyone to get out and enjoy the nice days we have.  Over the next three months, they may be few and far between.  With the long winter, many are anxious to go about regular outdoor activities and hobbies.  Based on previous La Nina winters, our summer could turn out to be hot and dry.  Mother Nature always seems to find a balance.