February 8th, 2009


A Benign Warmup

Wait, This Is February?

I'd wonder how it was it's not only no long January but we've killed a week of February, too. Except that I know exactly where January went and it was very busy. Sure, I've had this cold and its damned lingering clogged head for nigh over three weeks now, and that's cut down on some of my productivity and actually forced me to take a sick day. But I've also managed to get to ConFusion and do some panels there, done some writing, managed my courses, reasonably up to date with my paperwork, and so I don't feel so threatened that a month plus of 2009 has already slipped away. Crazy, isn't it?

February Is The Longest Month Of The Year

Or at least it seems that way most of time. But though we've had weeks of cold weather here in West Michigan, temps soared from the zeroes as late as Thursday to the fifties on Saturday. It's still only 42degF outside today on Sunday, but it's brilliant blue sky and the driveway is clear and dry. The forecast freezing fog and drizzle for yesterday and possible rain for today have not materialized, and though the frost depth is around 3-4 feet, this rapid thaw is happening without any rain so flooding should be minimal.

Indeed, the thin snow mat on the driveway, ice on the roads and snowbanks everywhere got beat down in a hurry. What? Three days in a row that didn't require 4WD to get to work? (grin) Madness, I tell you -- madness!

What I haven't heard anyone talking about ice cover on Lake Michigan. We like it when Lake Michigan freezes over, or at least a lot of it, because it stops the lake effect snow machine. So... this I was thinking about this, I went and Googled and found NOAA's web page on Great Lakes Ice Cover.

It is rare that Lake Michigan freezes over completely. Despite the area¹s reputation for harsh winters, the only year we are certain Lake Michigan approached being completely frozen over was 1979, when extended periods of low temperatures resulted in an extensive ice buildup in the southern half of the lake (see Figure 3). In an average year, ice covers a bit less than half of Lake Michigan¹s surface. Because the lake stretches about 300 miles from North to South, there is usually much open water over the deeper waters of the southern basin due to milder temperatures. Since airborne and satellite observations of lake ice began four decades ago, only two other years, 1977 and 1994, have seen periods when nearly 90% of the lake was ice-covered. Recently, warmer temperatures have kept the ice cover far below average levels. The icepack covered only 15% of Lake Michigan in 1998, even in late February when the icepack is usually at its greatest.

A very quick survey didn't find any current ice coverage details. But here's yesterday's MODIS satellite image of Lake Michigan. Not a huge amount of ice, but what's there is pretty eerie looking from space. Lake Erie, by the way, is a lot shallower than Lake Michigan and was/is freezing over.


Dr. Phil