12/1/14: On the First Day of Winter

December 1 marks the first day of Meteorological Winter, meaning Autumn 2014 is now behind us.  Although both September and October finished with temperatures either near or above average, Autumn 2014 still finished with below average temperatures for the 3 month period because of the exceptionally cold November.

 

Temperature Departures from Average September 2014

Temperature Departures from Average September 2014

Temperature Departures from Average October 2014

Temperature Departures from Average October 2014

 

November 2014 finished with temperature anomalies of 5 to 10 degrees below average.  Plus, many of you may have forgotten that the first week of November was fairly mild, so these well below average temperatures for the 30 days of November were muted somewhat by the warmth of the first 7 days.

 

Temperature Departures from Average November 2014

Temperature Departures from Average November 2014

Taken as a whole of all three months of Autumn 2014 finished slightly below average with many of the NDAWN (North Dakota Agricultural Weather Network) sites having negative temperature anomalies in the 1 to 3 degree range.

Autumn 2014 Temperature Anomalies from Average

Autumn 2014 Temperature Anomalies from Average

 

The NDAWN stations are only set up to measure liquid precipitation, so on November 1 of every year we turn off the precipitation measuring at our stations, meaning for the autumn season there is only data in September and October.  Those two months were quite dry.  Although there is no NDAWN data for November, taking data from the Cooperative Observers and airports, plus CoCoRaHS observers indicated that most of North Dakota recorded precipitation below average during the month, meaning that the season as a whole was quite dry.

September and October 2014 Precipitation

September and October 2014 Precipitation

 

December is starting off cold, but moderating temperatures are foreseen as the week progresses.  Temperature above average are anticipated by the weekend.  Little if any precipitation is foreseen this week.  The main weather feature for today will be the wind as a stiff south wind develops from west to east across North Dakota and western Minnesota over the course of the day.

Daryl Ritchison