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.
Last week there was a noticeable change in our weather. After recording only three days in the 70s over the previous 48 days, since last Thursday our high temperatures have been frequently in the 70s. Plus, on this upcoming Thursday and Friday, one (or both) of those two days may be only the second time this summer with a high in the 60s.
Is this a permanent change? My strong suspicion is yes. A major strong in the Arctic last week along with some subtle other changes in the flow pattern over the Northern Hemisphere has probably, at least in our region, put an end to the persistent heat of the past two months.
Back in 2006, our last warm summer, after recording 15 days with a high in the 90s (including two above 100) through July, the rest of that summer the temperature remained below 90 degrees. This month has the potential to be the first below average month in over a year and it would not surprise me if our autumn started cooler than average as well.
It does not mean there will not be anymore warm days, just that normal or slightly below normal temperatures look to be the dominate temperatures for a while.
As the eastern two-thirds of the United States continue with this prolong period of above average temperatures, other locations in the northern hemisphere have been experiencing a long stretch of the other extreme, colder than average temperatures. One of these locations is London that will soon be attracting international attention as the Olympics will begin in a few days.
If you caught any of the Open Championship coverage this past weekend, you would likely have noticed the lush green fairways and bunkers with puddles of water. Much of Great Britain has been experiencing a very cool and wet summer, although, most of the locals would not call the past two months much of a summer. The weather has been so chilly, that some athletes left for warmer climates to continue their training before the start of the Olympic Games claiming it was too cold.
Considering the forecast for this weekend, those athletes that left may regret not sticking around to get use to the cool and damp conditions that appear to be hanging around for the opening ceremonies.
Our long-term average number of days with a high temperature at or above 90 degrees in a year in Fargo Moorhead is 13. The past 20 years have recorded so many cool and damp summers that in turn, has actually brought that average down slightly. Last year on only ten days did the temperature reached 90 degrees locally, with eleven in 2010, just four in 2009 and six in 2008. So far this year, we have recorded 14 days with a high in the 90s.
That is, of course, more than during any of the previous four years. Yet, from a historical perspective, we are no where near what has been recorded in other years. Back in 1988, to this point, there had already been 24 days in the 90s (and some 100s) in the record breaking summer that ended up with 39 such days. In 1936, there had been 20 such days to this point with another 18 recorded during that summer. In 1910, a year quite similar to this year in many regards, we had recorded 21 days with a high at or above 90 degrees to this point.
We would need to reach 90 degrees another 10 times just to reach the top 10 in this category, which is something we have not done since that record breaking summer of 1988.
The phenomenally warm temperatures that we have been and will continue to record this month has many wondering if this has any implications for the upcoming summer. With every year being unique you can never make a definitive forecast. What happens in the upcoming months will be unlike any other year, yet, it will probably at least resemble or as I like to refer to it, rhyme with other years.
Looking back to the 20 warmest Marches on record, 16 of them, or 80%, in turn were followed by a summer that finished with a below average temperature. Granted, several of those years were close enough to the average to be considered “near normal”, but nevertheless finished on the low side of the average. Plus, for those of you who like hot summers, only 1 of those 20 years did the summer finish with a well above average temperature. Precipitation wise, only 2 of those twenty years finished with excessive rainfall contrary to many recent summers.
This should not be considered a forecast, but just an observation.
The summer of 2011 would likely not be described as hot as 90 degree weather was very infrequent with only 8 such days occurring. Yet, even with a lack of truly hot weather, this past summer finished well above average.
The summer of 2011 finished as the 13th warmest since 1881 with an average temperature of 70.7 degrees. That is 1.9 degrees above our current 30 year average of 68.8 degrees. One factor that played a significant role in making this past summer so warm was the low temperatures.
The average low temperature these past three months was 60.1 degrees which ranked as the 2nd warmest on average. Only the summer of 1988 had a higher average low temperature than this year and that summer only finished 0.1 degree warmer.
Not only was the summer of 2011 in the top 20 for temperature, but also for precipitation as 13.02 inches of rain was recorded in the past three months which ranked as the 19th wettest summer on record. The current summer precipitation average is 9.25 inches.
I have been asked on numerous occasions if I felt the rest of this summer would remain as cool as June has been so far. My immediate response has been to mention that this month has been far from cool, that in fact, the month has been running 1-2 degrees above average. With two days in the 90s, five days in the 80s and with many of the days we have been in the 70s in the upper ranges of the 70s, this month has recorded plenty of warm days for our climate.
Although the weather looks cooler the next few days, looking forward, this month appears to be on track to finish either near or slight above average. My original summer forecast was for this month to finish near or slightly below average with July and August finishing above normal.
With a mild June start, the summer is looking promising, at least temperature wise.
The summer season of June, July and August is tied with spring as the longest season of the year with 92 days. Looking back at the previous 130 summers in the record book, the next three months the high temperature will fail to hit 70 degrees on 11 days on average with most of those cool summer days occurring in June.
The high temperatures will be in the 70s on 33 days, the second most frequent high temperature in the summer. The most common high temperature during summer would be a high in the 80s. On average, 37 of the 92 days of summer will see a temperature between 80 and 89 degrees.
We have already experience two days with a high in the 90s and on average we can expect 10 total 90 degree days during the summer (and 13 during an average year). Since 1881 we have hit 100 degrees 79 times in summer (86 total) which brings the average number of 100 degree days to one per year, although we have hit 100 only 3 times in the past 20 years.
It was 103 degrees Tuesday in Minneapolis, making it the hottest day there since the scorcher of a summer back in 1988. Chicago hit 99 week, their hottest day in five years. Fargo Moorhead recorded 94 degrees the same day, the hottest here since it was 95 on May 29, 2010.
Already this summer there have been a couple of rounds of heat into the upper 90s along the Atlantic coast from Washington to New York. All of these heat waves have been quick, lasting only a day or two in most locations. The cause has been due the high-energy, high-amplitude jet stream which has also been responsible for all the bad storms across the country the past few weeks.
But once summer becomes established, the jet stream usually loses some of its energy and amplitude. So if we end up having a hot summer, it will be from a different cause than what is making these little heat waves at present.