A good Year for Few Tornadoes

The average annual number of tornadoes reported in the United States is about 1,260.  Fairly good records go back to 1953.  The average has been on the rise in recent years, mostly due to a much more active storm spotting network.  The most number of tornadoes in a year was 1,870 in 2004.  Other very active tornado years were 2008 and 2011 with more than 1,600 each of those years.  But for the last three years, there has been a dearth of tornadoes with fewer than 900 observed tornadoes in 2012, 2013, and so far this year.  In fact, barring an unusual Christmas tornado outbreak, 2014 will go down as having the fewest number of tornadoes on record in the modern era (since 1953).  So far, there have been just 814 tornadoes this year.   Meteorologist John Wheeler

When Breath Turns to Fog


It is so cold I can see my breath.” How many times have you ever heard someone say this?  But is it really the cold that causes you to “see your breath?”  And what is it that happens to air when you breathe it in that causes it to become visible?  To begin with, it is actually the relative humidity of the air you exhale which matters.  Conditions in the lungs are warm and extremely humid.  When you breathe in air, conditions in your lungs add heat and moisture very suddenly.  Exhaled air is about 95 degrees with about 95 per cent humidity.  As the air leaves your nose and mouth, it quickly cools and disperses.  But if the outside air is either very humid or very cold, some of that humidity will briefly condense into a cloud of visible water droplets.  If it is very cold, then the humidity of the outside air matters less.  But if the outside air is very humid, exhaled breath becomes visible even in mild air.     Meteorologist John Wheeler


Winters Can Change

In early December two winters ago, the Fargo Moorhead area had a measly inch of snow on the ground and we would still have just three inches six weeks later on January 27.  Then it started snowing.  We got five inches in January 28.  Then another ten inches fell February 10.  Four more inches fell in a series of little storms in February followed by 15 inches in March and another 17 inches in April.  Snow cover reached a maximum average depth in mid-March and we would not see the ground again until April 27.  It is impossible to predict if the remainder of this winter will be snowy or not.  But the winter of 2012-13 taught us that because winters are long in this region, they can change.  November was cold and dry.  So far, December is looking mild and dry.  But things can change.  There is a long way to go before spring.  Meteorologist John Wheeler

Cold November

November here in the Fargo Moorhead area was cold.  The month, as a whole, was six degrees below average. The first wave of cold air moved in November 9, starting an early winter run of 22 out of 24 days below freezing.  While impressive, the cold has set no records here.  We live in a region where early cold snaps must be expected from time to time.  However, as the cold air built into the Mid-South and Southern U.S., it did began setting records.  The most impressive was about a week after the initial front passed through Fargo Moorhead.  According to Dr. Ryan Maue of WeatherBELL, November 19, 2014, was the coldest November day across the Lower 40 since November 30, 1976.  A full 85 per cent of the Lower 48 was below freezing, with many locations setting both record lows and record highs for the day.  The pattern has since relaxed and now most of the U.S. is enjoying above average temperatures.  Meteorologist  John Wheeler


Winter Break

The milder weather coming our way is going to be a pleasant surprise for many who were shocked and depressed by the very cold and early start to winter last month.  But now the pattern is softening quite a lot, and temperatures into the 40s appear likely by late next week.  Most of us associate winter with very cold weather.  It is what we remember.  But weather in the 40s and even 50s in December is not that rare.  Last winter it was 40 degrees on December 27.  Early in December of 2012 there were three days above 40 including two at 50.  December of 2011 featured five days in the 40s including 45 Christmas Day.  Decembers in 2009 and 2010 had no days warmer than the 30s, so it doesn’t happen every year.  But any winter month has at least one day above 39 degrees more often than not.  Meteorologist  John Wheeler

Cold November, Warm November

November was a cold one here in the Red River Valley region.  In Fargo Moorhead, the average temperature for the month was six degrees colder than the average of the past three decades.  Twenty-two of the 30 days in the month were colder than average.  However, according to satellite-based measurements of the entire Earth’s surface, November was the second warmest of the 36-year satellite record.  The Upper Midwest and Northern Plains regions had the coldest temperature anomaly on Earth.  A region over the Arctic Ocean north of Alaska had the warmest temperature anomaly.  The warmest November in the satellite record happened in 2009, but that was also a mild November around here. So the opposite correlation between our region and the rest of the world may just be another tidbit of random weather.  We were just lucky (or unlucky) to have been so cold last month.   Meteorologist John Wheeler

Warm December Pattern

There are a number of large-scale weather features which can impact our long term weather and one of them is called the Pacific-North America Oscillation (PNA).  When the PNA is positive, there is strong low pressure in the Gulf of Alaska which causes the Polar Jet Stream to drop well south of Alaska across the Pacific, where it enters western North America and bring wet weather to the West Coast.  The Jet then curves northeast into Canada, allowing mild air from the south and southwest into the Northern Plains. This is almost opposite of the pattern in November, when the PNA was strongly negative.  There are other large-scale weather features which sometimes have a greater influence than the PNA.  But the PNA is looking very strongly positive for the time being, causing me to think our weather will be mild through Christmas.  Expect lots of afternoons in the 20s and 30s with a few in the 40s.   Meteorologist John Wheeler

November Was Cold and Dry

The month of November was cold and dry.  The average high temperature was 30.9 degrees and the average low was 14.9 degrees, for an overall average of 14.8 degrees which is 6.0 degrees below the long term average.  The warmest day was 57 degrees November 2.  The coldest morning was 13 below on November 27.  There were four days in the 50s, all early in the month.  There were five days in the 40s, scattered throughout.  There were just three days in the 30s. Fourteen days were in the 20s. There were three days in the teens and just one with a high in the single digits.  Precipitation was 0.71 inches with much of that falling in a 0.44 inch rain shower November 4.  Snowfall was 3.6 inches. Average precipitation is 1.00 inches and average snowfall is 7.9 inches.  With scant snow on the ground and the Jet Stream shifting to a weaker, more westerly flow, it is likely that December will be warmer and drier than average.    Meteorologist John Wheeler


The Core of the Winter

It is normal for our weather to fluctuate from colder than average to warmer than average. In winter, a change in the pattern can drive out Arctic air and replace it with much warmer weather for a while.  In the fall, this happened as well, but the general trend in fall is always toward colder weather.  A rogue warm day may happen anytime, but the last half of November is never warmer, overall, than the first half.  The change in incoming solar energy just will not allow it.  In December, even though the general trend is usually toward colder weather at month’s end, it is possible for the coldest weather to happen early in the month.  Likewise, mid-January is, on average, the coldest part of the winter; however it is quite possible for the coldest week of winter to happen at any time during the winter.   Meteorologist John Wheeler

Winter Highs and Lows

The past few days, our weather has not followed the normal night and day cycle.  Instead of it being coldest in the early morning and warmest in the late afternoon, the temperature rose steadily from arctic conditions Thanksgiving morning to balmy (for November) by early Saturday.  It has been falling steadily since then. This actually happens a lot in our region in winter.  Snow on the ground reflects much of the sunlight so there is less warming during the day.  Plus, our proximity to Arctic air to the north and Chinook-warmed air to the west means a switch in the wind can cause big temperature swings.  This does create confusion with the seven-day forecast in the newspaper.  The format makes it difficult to convey such irregular temperature patterns.    Meteorologist John Wheeler