December 2012

 

December 2012 continued the recent trend for near average temperatures.  Last month finished with an average temperature of 14.7 degrees which is 0.6 degrees above the current 30 year average.  The first half of the month recorded very mild temperatures but the second half of the month turned cold enough that in the end the month finished close to normal. Although the temperatures in recent months have been fairly close to average,

December was another month with total precipitation finishing below normal.  Our cooperative observer in north Moorhead measured 0.45 inches of liquid from the 5.1 inches of snow he measured (The airport reported 0.37 inches of liquid equivalency).

Average precipitation in December is 0.83 inches and the average snowfall is 11.2 inches.  Only three of the twelve months in 2012 finished with above average precipitation and all of those three months would be better described as finishing near the average

It Ain’t Over ‘Til It’s Over

Yogi Berra is probably more famous for some of his interesting quotes then he is for his baseball career.  Perhaps the most well-known is “it ain’t over ‘til it’s over”.  That is not only true in baseball, but also in weather and last year was a good example of that.

In the middle of December the year 2012 was running 0.8 degrees warmer than any other year since 1881.  With such a strong lead it appeared that last year was guaranteed of ending up as the warmest year on record, in fact, I wrote a couple of previous blogs stating just that.

But the last half of December was cold enough, especially the last several days, that in the end, 2012 finished less than one-tenth of a degree cooler than the record.  Rounded to the nearest tenth of a degree, the average temperature last year was 46.3 degrees, which did not tie nor beat the record of 46.4 degrees set in 1987.

The current average yearly temperature is 42.4 degrees

The Event of 2012?

At the end of each year, there are often stories highlighting some of the most important news stories of the previous 12 months.  In our climate there are often numerous weather events that could also be listed.

If I had to pick the most significant weather event in 2012 it would come down to either the record breaking warm temperatures or the dry conditions that plagued most of the area this past year.  Neither would necessarily be a snapshot in time like a tornado or a horrific blizzard, but instead a process that occurred over the entire year.  Because the dry conditions this year came after an extended stretch of extremely wet weather, the impacts were lessened to some degree.

It is because of that and the fact that 2012 will likely be the warmest year since 1881 with two well above average months of January and March that the warmth of 2012 gets my vote for the weather event of the year.

Autumn 2012

September, October and November comprise climatological autumn.  This past autumn the average temperature in Fargo Moorhead was 44.5 degrees, which happens to be right at our current 30 year average for the season.  November finished slightly above average, October slightly below and September right at the average giving us our very average autumn season.

One thing that was not average this past autumn was the precipitation.  During the past three months only 2.93 inches of rain and melted snow was recorded locally. That is 2.79 inches below the average of 5.72 inches.  Although the past three were quite dry, Autumn 2012 only finished as the 31st driest fall on record.

For the year, through November 30, 14.15 inches of rain and melted snow has been official recorded in Fargo Moorhead this year.  That ranks the first 11 months of the year as the 10th driest since 1881.

Cold First Half of October

Although the past two days were quite mild, as a whole, the first 15 days of October finished about 5 degrees below normal.  That is an incredible 19 degrees colder than the first half of October last year.   Although, it should be noted, that the first half of October 2011 was the warmest such period on record.  The second half of 2011 and much of this year recorded above average temperatures.

Then the past two months, August and September, finished near normal and the current pattern, at least for now, has transitioned to a cold one.   The last time with an extended period of below average temperatures was in May, 2011. Looking forward, it appears much of the rest of the month will record temperatures below normal, meaning that this month will likely be the coldest, based on the average, in 17 months.

This October has not only been cool, but also dry, with only 0.43 inches recorded through Monday which is 0.67 inches below average.

Leaves and Snow

One of the concerns with the snow storm last week was the potential for power outages.  Because the leaves were still on the trees, the surface area that snow can accumulate on was greatly expanded.  With temperatures above freezing, the snow that fell was quite heavy as it had very high water content.

The average ratio of water content in the snow in this area is 14:1.  Meaning it would take 14 inches of snow to equal 1 inch of rain.  Last Thursday’s snow event that ratio was as low as 4:1.  A gallon of water weighs 8.3 pounds.  If you took a gallon jug of water and hung it on a tree branch, you would quickly realize how easily some branches can bend.   With so many power lines near trees, the snow laden branches in several cases either touch the lines causing arcing to occur, or just fell on the line breaking it.

Either way, power was lost for many and for some for a very long time.

Dry September

As you have likely heard by now, last month was the driest September on record as just 0.12 inches of rain was recorded at Hector Int’l airport.  The previous record was 0.13 inches set back in 1974.  Setting monthly records is often a matter of location and timing.  Location is especially important when dealing with rain.  Spot to spot variation in rainfall can greatly alter a ranking.

For example, last month at the WDAY studios we recorded 0.17 inches of rain.  That would have ranked September as the 4th driest. .  Our state climatologist recorded 0.24 inches last month in his backyard which would have ranked as the 6th driest.   In Harwood, just north of the airport 0.43 inches was measured, that would have ranked as the 13th driest.

Plus timing is important in the sense does the rain fall or not fall within the arbitrary days we refer to as a month. But timing and location matched perfectly last month for a record that may stand for a long time.

August 2012

Although the end of the month may not have felt like it, as a whole, the month of August was our first month since May, 2011 to finish with an average temperature below normal.  Last month the average temperature was 68.8 degrees which is 0.5 degrees below the current 30 year average of 69.3 degrees.

Granted, that means last month finished right at the average, as did a few other months in the past year, yet, it was still the first month to finish even slightly below average to end our above average streak at 14 months.

Last month may have finished near average for temperatures, but well below average for precipitation.  The airport recorded only 0.92 inches of precipitation during the 31 days of August.  That was the lowest total since 1984 (which was the driest on record with 0.18 inches) and tied last month as the 13th driest since 1881.

Summers to Remember

When I was a kid, my dad would tell me great stories of the summer of 1936.  The details of the extreme heat, dust storms, and true or not, his story about being able to throw a rock across a nearby lake (which is usually about 200 yards wide).  Perhaps what fascinated me the most was that he slept outdoors as it was too hot to sleep inside because as a kid, sleeping outside without a tent sounded like a dream come true.

As I was finishing up graduate school, I was to some degree able to live through my own 1936, the summer of 1988.  Granted, the heat was not quite as extreme, but the number of 90 degree days was about the same.  Plus, although I did not have an air conditioned room, two fans placed in the window allowed me to spend those summer nights inside, not outside, yet, I felt like I at least could understand to a small degree what my dad lived through a bit better than I did previously.

Another generation was born and never really experienced a hot summer, until perhaps this year.  My dad had 1936, my summer was 1988 and perhaps my kids will tell stories about the summer of 2012.

It was a Warm July

Based on what the projected temperatures are today, it seems likely that this month will end up as the 2nd warmest July on record.  Currently, 1916, 1989 and 1988, 1935 and 1957 are all virtually tied for that position, but they do technically rank in the order listed.

If you are surprised that this month ended up warmer than 1988 and 1989, the years many readers will remember, it was the low temperatures this month that made the difference, not the high temperatures.  July 1988 and 1989 had a noticeable higher average for daily maximums, but those months also had much cooler nights than this year.

Although this July will rank as the 2nd warmest on record, it still comes far short of the record warmest July set back in 1936. In fact, this month will likely end up around 3 degrees cooler than what was recorded that year, which averaged over a full 31 days is very significant.

But that should not take away from this month as it was certainly a July many of us will not be forgetting anytime soon.