Is Grand Rapids getting warmer????

posted in: Michigan Weather Forecast, Slim | 14

I know that not many days go by with some post on how warm Grand Rapids has gotten on one or more days. And in the winter time there are also many days of how much snow has or will fall or how cold it has or will become. So l thought it would be a good idea to see 1 what is the average annual number of days Grand Rapids has had (averaged out over the 30 year period of 1981 to 2010) and 2. just what the average is for each month in the current 30 year period and the older period of 1971 to 2000. And then see what the average is at the last 15 years (to get a hint of the next 30-year average) I know most climate scientists like the 30 period but there are some who are pushing for a 10 or 15 year period. I think there should be the 30 period and a longer 50 and or 100-year period for a longer time frame.
Ok now just for the fun of it here is the average annual number of days Grand Rapids has had for some milestone temperatures. In the current 30 average period (1891/2010) the annual average of 100° days is 0.77 (that is less than 1 per year) for 90° days the average is 8.4 So far 2018 has had 5 so we are off to a good start. Note some sites list the average number of 90 days at Grand Rapids as 10. The annual average number of days at or above 50 is 226.3 the number of days where the high is 32 or lower is 47.3 the average number of days with the low of 32 or colder is 126.4 and the number of days with a low of 0 or colder is 4. As for snow falls the average number of snow fall of 3” or more is 8 for 5” or more it is 3 and for 10” or more it is .5 so big time snow storms are rare here.
Now for some real fun. Is Grand Rapids getting warmer? On way to try and tell if a location is getting warmer or cooler is to look at the average mean temperature for each month. The “official” Climate Normals are a 30 year average mean that is updated ever ten years the current 30 years that are used are 1981 to 2010 the previous cycle was 1971 to 2000 and the next cycle with be 1991 to 2020. What I have done is looked up the average monthly mean temperature at Grand Rapids first set I used is the unofficial average means from 1963 to 1971 (I used 1963 as that is the year the current location was used) the next set I used was the official 1971 to 2000 cycle and next was the official 1981 to 2010 cycle (the currently used cycle use so when one says “average” or “normal” this is the one that is now used. I then used another “unofficial” mean average from 2010 to 2017. And just for a comparison I also use another “unofficial” average mean for a 100 year cycle from 1917 to 2017. Here is the results of my findings.

January

1917/2017  23.6°  1963/71 21.2°  1971/00 22.4°  1981/10 24.4°   2010/17 24.6°

February

1917/2017 23.6°   1963/71 22.6°   1971/00 25.0° 1981/10 26.8°  2010/17 25.3°

March

1917/2017  34.2°   1963/71  32.5°   1971/00  34.6°   1981/10  35.6°   2010/17  35.7°

April

1917/2017  46.5°   1963/71  46.0°   1971/00  46.3°   1981/10  48.0°   2010/17  48.3°

May

1971/2017   57.8°   1963/71  56.3°   1971/00  58.1°   1981/10  58.7°   2000/17  58.9°

June

1917/2017  67.7°   1963/71  67.6°   1971/00  67.1°   1981/10  68.4°   2000/17  69.5°

July

1917/2017  72.1°   1963/71  71.1°   1971/00  71.4°   1981/10  72.5°   2000/17  72.8°

August

1971/2017  70.3°   1963/71  68.7°   1971/00  69.4°   1981/10  70.8°   2000/17  70.2°

September

1917/2017  62.6°   1963/71  61.3°   1971/00  61.3°   1981/10  62.8°   2000/17  64.2°

October

1917/2017  51.2°   1963/71  51.9°   1971/00  49.9°   1981/10  51.0°   2000/17  51.6°

November

1917/2017  39.2°   1963/71  38.9°   1971/00  38.4°   1981/10  40.1°   2000/17  40.6°

December

1917/2017  28.3°   1963/71  27.4°   1971/00  27.6°   1981/10  29.2°   2000/17  29.9°

 

So is Grand Rapids getting warmer? Well every month is now warmer (using the 1981/2010) vs the 1971/2000 mean averages. It is also now warmer then the 100 year average. Now lets look at the annual mean average for the period of 100 years 48.2° the annual mean average for 1963 the year the temperatures started to be taken at GRR to 1971 47.2° 1971/00 47.7° 1981/10 48.4° and in the 2010 to 2017 the mean annual average has been 49.9° So the case can be made that in the Grand Rapids area it has indeed gotten warmer over the last 100 years. More so in the colder winter months than the summer months. Note this is not to be taken as proof of warming on a much long term and what if any is the cause of this apparent warming

Slim

317 total views, 3 views today

newest oldest
INDY
INDY

Slim like your post .. I hope Bill Steffens looked at it … Very nice day outside INDYDOG14!!

Mark (East Lansing)
Mark (East Lansing)

Holy smokes, Slim. You have way too much on your hands (lucky for us!). That is a great post. I wonder if urban sprawl may be the reason for the increased temps.

Barry in Zeeland
Barry in Zeeland

Not related to this post, here is my favorite pic from yesterday showing me on top of the world!

http://tinypic.com/usermedia.php?uo=NuVqmzAy%2FKxU%2FuCTsOCeTYh4l5k2TGxc#.Wy5QrxtMGhA

It is just stunning and amazing out here!

Sandy (Hudsonville)
Sandy (Hudsonville)

Nice photo!! Thanks for posting them.

Mark (East Lansing)
Mark (East Lansing)

Is that near the “Continental Divide” sign – aka Loveland Pass?

Barry in Zeeland
Barry in Zeeland

Not to far, it was near the top of Independance Pass.

Mark (East Lansing)
Mark (East Lansing)

Sweet. God’s Country right there.

Barry in Zeeland
Barry in Zeeland

Yes it is!

Barry in Zeeland
Barry in Zeeland

Amazing post Slim! Being a stat lover, I think this is your best post ever! Extremely interesting. Having grown up here in the 1970s, it has always seemed like it was colder back then, but it’s hard to trust memories. The way you have laid it out proves what I have always thought, but never did the leg work to see if it was indeed the case. You must have spent some decent time compiling all this data. Well done!

Sandy (Hudsonville)
Sandy (Hudsonville)

Great post Slim!! Interesting read.

MichaelV

Great post Slim!