Cooler PatternOctober 15th, 2013 at 11:56 pm by Bill Steffen under Bill's Blog, Weather
Click on the image to enlarge. UPDATE 1) Accu-Weather winter forecast would favor a good amount of snow for Michigan. 2). Pattern change indeed. 3) WOW! Look at the European model…that’s chilly! 4) CFS forecast for the rest of the month would put West Michigan about 5 deg. colder than average. However, I bet the model isn’t taking into account warm Lake Michigan, so I would not be quite that cool, but overall a cool pattern. If clear with calm conditions, frosts and freezes possible and certainly a day with waterspouts on the Great Lakes a possibility. 5) GFS would bring first snow to West Michigan, though again, with warmer Lake Michigan I think rain is more likely. 6) More than a dozen fatalities in Oshima, Japan landslide caused by rain from Typhoon Wipha. Tokyo had a gust to 73 mph and 9.92″ of rain! Check out this picture of the storm at Yokosuka AFB south of Tokyo. 7) Death toll now 144 from E-quake Tues. in the Philippines. Another powerful e-quake today in the Western Pacific. 8) Snow on the ground over much of the state of Wyoming. We’re seeing a major shift in the weather pattern over the Great Lakes Region. This is a map (500 mb – a constant pressure surface) that shows the general flow of air around 18,000 ft. above sea level. You can see we have a ridge over the West Coast of North America and a trough over the Great Lakes. Ridges are usually associated with warmer than average weather and troughs with cooler than average weather. The map is for the early morning of Oct. 24th (GFS). Our air flow will be coming out of northern Canada down across the Great Lakes. After a three-week stretch of generally sunny and warm weather, we are headed into a period of colder temperatures, more cloudiness and more frequent showers. From Sept. 24th to Oct. 12th, we had only one day when the high temperature failed to reach 70 degrees. From Sept. 27 to Oct. 13, the average temperature for Grand Rapids was 7.2 deg. warmer than normal. From Sept. 23 to Oct. 14, we had 75% of possible sunshine, compared to an average for that period of 51%. The above average sunshine and mild temperatures have pushed the fall color change a week later than average. Now, we’re going to see a lot of days with high temperatures from the upper 40s to mid 50s and a chance of showers more days than not. Early next week we’ll probably see the first snow in Upper Michigan. The average date of the first inch of snow in Grand Rapids is November 9th. Lake Michigan is quite warm (63 degrees). That warm water can warm the air a little as it crosses from Wisconsin. It also can provide moisture for more cloudiness and occasional showers when the air is cold enough and it will likely bring the possibility of cold air funnels and even a few waterspouts. These waterspouts are not associated with strong thunderstorms and the rotation is generally weak (under 50 mph). Remember these waterspouts last month off Kenosha WI.