The heat will likely stay on for August along with dry conditions

by CBS 3 meteorologist Dave Anderson

Back in the day, I did pretty well in the science classes offered by Ely teachers like Miss McLeod, Miss Tornquist, Mr. Wetzel, Mr. Mischke and Mr. Anderson. Despite the best efforts of teachers like Mr. Anderson and Mr. Lunceford, I did pretty bad in math classes. However, I did pretty well in college at statistics.
So, a few weeks ago, I was prowling online for information about Duluth’s hottest day in recorded history. I found a list of the hottest temperature recorded in Duluth for each year back to 1918. The info is spotty for the teens, 20s, 30s and 40s but complete for 1950 to today.
Using my ancient statistics skills, I factored those annual highs together to come up with an average high temperature per decade. Here they are from coolest to warmest: The 1990s averaged 89.4. The 1950s averaged 89.8. The 2000s averaged 90.4 The 1970s and 2010s averaged 90.9. The 1980s were warmest with an average annual high temperature of 91.3.
The numbers seem awfully random to me and don’t show any sort of steady increase from decade to decade. Does this mean climate change is fake? Probably not. The American Meteorological Society’s Statement On Climate Change says daytime highs are being relatively unaffected. It’s the overnight lows that are warming faster than natural phenomena can explain.
Can we blame this summer heatwave and drought on climate change? It is difficult to do that because the AMS states that neither short term warm spells nor short term cold snaps are prima facie proof of long term changes. And, the Minnesota DNR’s climatologists say the general trend for precip in our state has been towards wetter than normal conditions brought on by climate change. A drought caused by climate change would be counterintuitive to that thinking.
So what is causing this warm summer? It’s mainly a persistent ridge of high air pressure. Highs feature sinking air which puts down clouds and allows in extra solar radiation to raise temperatures. Highs spin in clockwise circles and often use that circulation to bring warm southern air into our region. And, sinking air in a high heats via compression at the rate of 5.5 degrees per thousand feet. All that together makes for warm conditions.
What goes up must come down. If we have a persistent high making us dry right now, there must be a counterbalancing trough of lower pressure somewhere. This summer, it is in Europe and they have been having torrential rains and major flooding troubles.
Here in August, we will continue to be warm and dry. Warm means an average of four degrees more than normal. Dry mean a shortage of two inches of rain. August 1st to 6th should be hot and stormy. The 7th to 18th should be hot and dry. The 19th to 23rd will be sunny but cool. The 24th to 31st will return to hot and stormy.