Another fall storm arrives with more wind and rain this week

Posted at 5:14 PM, Nov 15, 2015

WEST MICHIGAN — Whether people admit it or not, last week’s powerful fall storm was one for the record books. High wind warnings, lakeshore flood warnings, trees down, thousands without power, it was big in the scope of things. While our goal is NOT to alarm or hype this type of weather, my weather story posted days in advance was simply meant as a “heads up” as to what was coming. I supply the information, what people choose to do with it is up to them.

I mention that only because there are always those that think these articles are hype and the storms are no big deal. Thousands flocked to the lakeshore to see the 15 to 20 foot waves! Storm warnings were posted on Lake Michigan (rare in and of itself) and it didn’t disappoint. I was even more pleased to see everyone heeded the warnings and no lives were lost off the piers. The thumbnail attached to this story shows the next low pressure system tracking in to the western Great Lakes with rain and wind and is the image is valid on 6PM Tuesday.

This week another strong fall storm will affect the Great Lakes Tuesday and Wednesday. It will produce rain and plenty of wind, but not to the magnitude of last week’s storm. We’ll start off breezy on Tuesday and conditions will become windy through the day. Rain will likely develop in the afternoon. This time, winds will be southeast ahead of the arriving system and switch to southwest once the front goes through and we get behind it on Wednesday. Preliminarily we’re looking at sustained winds of 20 – 30 mph with gusts of 40 or better likely.

Take a look at the series of computer forecast model images below. You’ll see the outline of the United States and the thin gray lines which are isobars…lines of constant or equal air pressure. The closer together those lines are to each other, the stronger the winds over that region. All the color on the map represents accumulated precipitation. Red, yellow, light green, dark green, light blue, dark blue, light purple, to dark purple indicates where the precipitation will be the heaviest (a gradiation of colors from heaviest to lightest). The image below is a surface map and is valid for Tuesday morning. Note the “L” pressure system developing over Nebraska…it’s the center of circulation around the low.


The next model map (below) is valid for Tuesday early evening. Note how the “L” or low has moved in to northwest Iowa.


Next (below) is the forecast model for Wednesday morning. The low has already moved in to Canada above Minnesota and the isobars over Michigan are packed quite tightly.


Below Wednesday evening shows most of the heaviest rain moving out, but windy conditions remain.


And the last map below is valid for Thursday morning. No precipitation overhead but very windy conditions.


These fall storms can sometimes pack a punch. The greater the temperature difference (or gradient) between hot and cold, the more the atmosphere has to work at obtaining equilibrium again. That said, it’s typically this time of year (and spring) we see the greatest temperature differences and the strongest systems. I’m not necessarily talking about the amount of rain of snow, but the meteorological dynamics of how/where it forms, strengthens, and tracks.

One thing this system will do is eventually pull down the coldest air of the season by the end of the week. Our forecast models are showing the possibility of accumulating snow next weekend with high temperatures that may not make 40! Take a look at the forecast model valid for Wednesday morning. These are air mass temperatures about 5,000 feet above the surface. Warm! You can tell by the colors over Michigan.

WED AM 850

The next image below is the same forecast model but is valid for Friday morning. Notice the sharply colder tones over Michigan…the coldest air thus far this season if these models are correct!

FRI AM 850

Again, not trying to alarm here, just a “heads up” as to what may be coming. Have a pleasant week. Stay safe, and don’t forget you can always get the complete forecast at