Wednesday, October 19, 2011

Winds Cranking Up Across Lake Michigan / Chicago Area...

As promised in a post earlier this afternoon, winds are steadily increasing across Lake Michigan and into the Chicago Metropolitan area this evening.

I want to show you data from 2 buoys on Lake Michigan, marked 1 and 2 on the map below:

First, the data plot from buoy #1, which is located 43 nautical miles East/Southeast of Milwaukee, or about 55-60 miles North/Northeast of Chicago:

The winds on this particular plot aren't all that impressive yet, gusting to 46 mph (although that is certainly a healthy wind gust in anybody's book).  The thing I really wanted to point out on this graphic is the dramatic plunge in barometric pressure over the last couple of hours (bright green line), to a current reading of 29.59 inches of mercury.

Further South, closer to Chicago, the data from the buoy located at point 2 on the first map is located below:

This particular buoy is not reporting barometric pressure, but is recording very impressive sustained winds of 49 mph, with gusts to 61 mph at this time.  This buoy is located about 8 miles offshore of Chicago.

In Chicago itself right now, at O'Hare Airport, the wind is sustained at 21 mph with gusts of 30-35 mph, as shown by the graph below:

At Chicago's Midway Airport, which has less trees and buildings to the North to break-up the wind, sustained levels are currently at 30 mph with gusts of 40-45 mph:

The strong winds are really just getting started across the region.  Widespread sustained winds of 40-50 mph with gusts to 65 mph can be expected area-wide by Midnight, continuing into much of the night and into Thursday.

As pointed out in the earlier post, the strong winds blowing unimpeded from North to South across the entire length of lake Michigan will result in considerable wave action and water pile-up along the lakeshore in Chicago and on into the Indiana and Michigan shores as well.

Below are the latest wave height forecasts, valid 10pm, 1am and 4am CDT, respectively, this evening and tonight:

The darker orange shaded areas show where 15+ foot waves are forecast, while the darker red shaded areas depict 20+ foot waves.  This will cause considerable battering of the shoreline and water pile up will result in flooding of many areas along the lakeshore.

Storm Warnings, High Wind Warnings and Lakeshore Flood Warnings are in effect for much of the region tonight and into much of the day Thursday.  Winds and waves will begin to subside from Northwest to Southeast across the region by late afternoon on Thursday.

If you enjoy reading 'The Original Weather Blog', please be sure to "like" our facebook page!

No comments: