Recently there has been some discussion as to why the mean at Grand Rapids has been cooler than several other locations in Southern Michigan recently. Here is the letter that I wrote.
Dear Sir or Madam,
I post on a local weather blog
https://michigan-weather-center.org/
And on out blog there have been some who have been wondering why in the last year or so that Grand Rapids seems to have became cooler on average compared to the current 30 year average than several other locations in lower Michigan. For a example as of today April 25th Grand Rapids has a April mean of 43.2 for a departure from the 30 year average of -3.1 while at Lansing to the east they have a mean of 45.8 for a departure of 0.0. I have made the explanation that some of that has to due with the timing of cold fronts and clouds and or rain moving if here in GR before Lansing and some could be explained by colder air coming in off of Lake Michigan. But that said we have one poster that seems to think that there could be a issue with the recording equipment. If you could reply on this it would be helpful.
Thanks
James
Here is the reply.
Hi James-
Good question, and you are definitely on the right track with your hypothesis. Because we’re in April, the temperature extremes (like we’ve seen so far this month) can be drastic from one day to the next. The positioning of warm and cold fronts as they move through can mean the difference of 10 degrees or more on the high and low temperatures. Southern and southeast Michigan have had warmer temperatures than Grand Rapids, partly due to frontal position and timing as well as due to the influence of clouds and precipitation from Lake Michigan. Flint is an excellent proxy for Lansing, and that city is sitting at -0.7 degrees below normal this month, while Lansing is -0.4. Please note that high and low temperatures are reported for the calendar day, not daytime highs and nighttime lows necessarily. For example, it is possible in the winter and spring to have high temperatures occur close to midnight depending on frontal timing. Lansing had one such case early Monday morning when the high of 66 (with SSW winds) was reached shortly after midnight before the front came through. However, the front had already come through Grand Rapids by that time and temperatures were already dropping. Thus, only a high of 56 for Grand Rapids. You can see how these kinds of situations add up over the course of a month and the departures can be different. Welcome to spring!
Brandon Hoving
Observing Program Leader
Meteorologist
National Weather Service
Grand Rapids, MI
I hope this clears up any concerns that anyone may have as to why it seems to be cooler at Grand Rapids then to some locations to the east and southeast of GR
Merry month of May
May is the fifth month of the year and here in the Northern Hemisphere it is the last month of spring. Late May typically marks the start of the summer vacation season in the United States and Canada. At Grand Rapids we start the month off with a sun up time of 14 hours and 7 minutes and end the month with 15 hours and 7 minutes for a gain of one hour.
In Grand Rapids the average high starts out at 64.3 and ends the month at 74.9. The average low starts out at 43.2 and ends the month at 53.8. The all time high for May is 95 on May 31, 1934 on May 28, 2018 the high reached 94. The record low of 21 was set on May 1st, 1903. The most snow fall on any day in May is 5.5” and that amount fell on May 10th in 1902 and that same amount of 5.5” was reported on May 9th, 1923. The record wettest May is 10.01” and that fell in May of 2001 and the driest May was in 1936 when just 0.72” fell. Here are some May top 5’s There have been a total of 12 years when measurable snow fell in May The last time was on May 1st, 1994.
The average May mean at Grand Rapids is 59.2
Warmest mean temperature
- 1977 65.7
- 1896 65.3
- 1982 65.0
- 2018 64.8
- 1911 64.5
Coldest mean temperature
- 1997 50.3
- 1924 50.7
- 1945 50.7
- 1947 51.1
- 1917 51.7
Snowiest May’s of record
- 1902 5.5”
- 1923 5.5”
- 1954 3.0”
- 1940 0.8”
- 1935 0.4”
Wettest May’s of record
- 2001 10.01”
- 2000 9.59”
- 2004 9.29”
- 1981 8.29”
- 1911 7.18”
Driest May’s of record
- 1936 0.72”
- 1987 0.94”
- 1925 0.98”
- 1961 1.03”
- 1971 1.05”
Last year the mean for May at Grand Rapids was 57.5 that was a departure of -1.7° the high for the month was 86 on several days and the low for the month was 30 on the 1st the last recorded 32 was on May 7th
Slim
The weather the next 3 days will be pathetic! Cloudy, cool, wet and windy! Nothing new, but pathetic!
A wee bit o thunder to my West…must be nice.
We have had thunder and lightning and it is pouring out there. This is round two for the night. Nothing severe.
Another lousy Spring day! I think during the entire month of April we only had a handful of really good Spring days! Horrendous weather!
One month with some 90’s I can handle that …InDY
I hope we have one of those summers with ZERO 90 degree days and lots of low humidity days with a temp around 80 degrees! Now that would some good golf weather or good weather for any outdoor activities!!!!
More rain, cold and clouds are coming! Surprise?
You couldn’t pay me to be golfing right now! Cloudy, temp around 53 degrees, 20 MPH winds and wind chill in the mid 40’s! No mookie and Andy this is not good golf weather unless you are desperate! Horrible Spring weather so far!
Yes we could be setting a record this year for cold, cold and more cold! I can only hope it carries through to next winter so we can get pounded with cold and snow! Bring it on!
Sadly, a “throw away” year is upon us. Cold, with nothing but more cold coming. Oh well…life in The Southern Arctic.
Bring it!
Yesterday was a very pleasant day there was about 67% of the possible sunshine. The official high/low was 62/42 at Grand Rapids. For the month of April all of the reporting locations in Michigan will end up below average. I would like to point out that the 30 year mean at Grand Rapids is warmer than Muskegon, Lansing, Flint, Saginaw, But Grand Rapids 30 year mean is cooler than Detroit and Kalamazoo.
The overnight low here at my house was 48 and at the current time it is cloudy and 50.
Slim
Slim on top again …No make up or false reports ask the horse receive the source… As we been saying since February look for a below average Spring kind of fits the cold Winter we had keep it going into Summer..InDzy
Nice work, Slim. When in doubt, go right to the source.
The below normal temps keep rocking! This could go down as the coolest year vs average this century! If you like clouds, wind, chance of showers, and temps in the mid 50’s then you will love the weather today! This is horrendous weather for the last day in April! Give me sun and temps in the upper 60’s to low 70’s! We may not see this type of weather for weeks! Incredible!
Nothing new with the facts that GR is colder than Lansing and points to the East in our state! This is obvious and has always been the case! Give me a break!
The 30 year mean at GR is warmer than Lansing, Flint but is cooler than Detroit and Kalamazoo.
Slim
Interesting and part of that may be due to some winter lake effect warming for GR and clear and cool nights in Lansing during the winter!