July cooldown this week: How normal is it?

Posted at 7:51 AM, Jul 14, 2014
and last updated 2014-07-15 13:26:57-04

GRAND RAPIDS, Mich. (July 14, 2014) — We’ve been advertising a substantial cooldown in the forecast for early this week; as one might imagine, it has many people in West Michigan worked up about the unseasonably chilly weather.

As always, though, we do our best to provide perspective about the forecast, so we’re giving you a comparison to some of the averages and records for West Michigan.

As Tuesday will be the coolest day this week, here are the daily averages and records for July 15th based on the entire history of data in Grand Rapids and Muskegon:

  • Grand Rapids
    • Average High: 83.0°
    • Average Low: 60.9°
    • Record High (Hottest): 95° (2013 and other years)
    • Record High (Coldest): 58° (1987)
  • Muskegon
    • Average High: 79.6°
    • Average Low: 60.9°
    • Record High (Hottest): 93° (1995)
    • Record High (Coldest): 61° (1987)

As you can see, it will be well below average on Tuesday, but nowhere near record territory in terms of the cool weather.

One of the interesting things about records, though, is that they are highly variable day-to-day.  As a result, we may still break a record on Wednesday even though it will not be as chilly as Tuesday.  The reason for that is the coldest high on record in Grand Rapids for the 16th is 74°, a far cry from that 58° the day before.  Our current forecast high for Wednesday is 73°, so breaking that record will be a close call.

What’s perhaps more telling, however, is how typical a similar cooldown can be in West Michigan in the summer.  In 24 of the last 50 years in Grand Rapids, there has been at least one day in July with a high temperature below 70°.  So, basically, the conditions we’re expecting this week happen normally close to half the time.  The average for the coolest high temperature in July is 70°, and we only expect to be a couple of degrees cooler than that.  In other words, this is a pretty typical cool spell by West Michigan standards.

For the time being, we don’t see any significant heat building across the region for the next week and a half.  You can check out the 7 Day Forecast on the Weather page.