If your friends, coworkers and fellow townspeople are at all like mine here in the upper Midwest, then you've been hearing a lot of depressed and dismal talk lately about the cloudy, overcast, gloomy weather we've been enduring for the past month and a half. The type of cloudiness has varied from a high, heavy blanket of grey to a low, misty haziness. Inuits are supposed to have 20 different words for 'snow'; perhaps we need 20 different words for 'cloudy'. Everyone seems to be ready for a few days of sunshine to lift their spirits. One of my coworkers remarked today that her little 3-year old daughter has asked "Mama, is it day?" several times during the past week in the middle of the afternoon.

In Michigan's Upper Penninsula, it's common for folks to consider taking prescribed light treatments to combat Seasonal Affective Disorder or just general winter blues when the long dreary winter becomes too much to bear. I bet the light booths are fully booked this season. Some people seem to be more susceptible than others to this sort of season- and weather-induced depression, but it's pretty much a universally accepted medical condition and I'd bet more folks than average are affected in Michigan this winter. It's been atypically warm and cloudy.

It seems that many of my fellow Michiganders are also under the impression that, wherever we live here in Michigan, it's the "second most cloudy city in the country" or some similarly extremely cloudy place relative to the rest of the US. I hear that generalization a lot here, and I also heard it just as frequently from residents of Ithaca, NY when I lived there. We seem to be comfortable assuming that somewhere in the Pacific Northwest lies the cloudiest city, but 'here' is a close second. Wherever 'here' is.

I decided to find some cold, hard data on the frequency of cloudy days and put this subject to rest in an objective manner. The National Oceanic & Atmospheric Administration (NOAA) keeps track of just this sort of thing. I found a list of historical mean cloudy days per month and per year for almost 300 cities within the United States and its territories. The means are based on 30 to 50 years of weather observations for each city. I perused the data and decided to throw out the data for about 40 cities for which the sum of clear, partly cloudy and cloudy days did not equal 365 days per year +/- 2 days. I ranked the remaining 269 cities in order of increasing number of clear days per year. I graphed the results for a subset of recognizable cities I thought might be of interest to the readers of this blog. (Sorry Canadians... I didn't access Canadian weather data!)

(Click the graph to enlarge it and make the x-axis significantly more legible.) The graph shows the mean number of days per category of cloudiness for a subset of cities I chose from the list of 269. The cloud cover categorization was determined for daylight hours only. 'Clear' denotes zero to 30% average sky cover, 'partly cloudy' denotes 40 to 70% average sky cover, and 'cloudy' denotes 80 to 100% average sky cover. According to this data, cities surrounded by ocean, such as those located on islands in the Pacific Ocean, appear to be the cloudiest. The cities of Chuuk, Pohnpei and Yap in the Caroline and Marshall Islands top the list with an average of about 300 cloudy days per year. The first sizeable, recognizable city in this list is Juneau, Alaska with 280 cloudy days per year. Lansing and Detroit, Michigan - closest to my location - are almost halfway down the graphed subset with 191 and 185 cloudy days respectively. This is a long way from the 'second most cloudy city in the country' status, but at the same time, 190 cloudy days per year is a lot. The least cloudy cities in the list are Las Vegas, NV and Yuma, AZ averaging only 73 and 52 cloudy days per year. No cities averaged less than 52 cloudy days.

A bright sunny, clear day sounds really really wonderful. Though it's been dismal enough that I'd gladly take a day of only 80% cloudy. That'd be an improvement.

UPDATE: I should express my fantasies on this blog more often I guess. I'm gazing at about 80% cloud cover today, but I can see actual blue through the holes in the fluffy, white, swiss cheese clouds. And as I type this, I'm enjoying having to occasionally squint through the glare off my computer screen. I do not have the same view of the glare during nicer weather. Sharp, distinct shadows, lasting about 10 seconds, appear every little while. It's colder, overnight temperatures dropped to 19 ^oF (-7 ^oC). Things are looking up!

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