Welcome, arctic express. After the powerful low moved out, arctic high pressure has moved in. The pressure gradient between the two created the high winds which are now thankfully dying down. So how does the low we had on Saturday-Sunday compare to the low on October 26-27? If you follow this blog, you know about the LRC, a weather theory that hypothesizes that a repeating weather pattern sets up every fall and continues through the winter and spring. It is fascinating to watch. Take a look at the two storms. I’ll start with October 27th.
This is a 500 mb chart of the massive wind storm that brought 60 mph winds to our area. Note the locations of the highs and lows. Here is the storm from Sunday.
The low last Sunday was clearly farther south, but that is to be expected with seasonal changes. Normally, with a winter-time pattern, the jet stream is farther south, thus the lows will be farther south. The ridge, or high pressure over California is much more pronounced in Sunday’s storm, but still can easily be seen on October 27th. The low in central Canada is farther east which I think is a component of the ridge in the Atlantic being weaker. Finally, the low in the northern Pacific is in a very similar position. Overall, these two storms, separated by 46 days are quite similar. I just wish the LRC could have helped with forecasting how long the rain lasted in Milwaukee before we finally changed to snow on Sunday morning.
As for our forecast, it is going to be brutal again tonight. The good news is that we have lighter winds. The bad news is that temperatures will be even colder. No wind chill advisory because winds will generally be less than 10 miles per hour and wind chills will not reach advisory criteria, usually around -15 to -20.
For those of you who have always wanted to know how the wind chill is calculated take a look:
The formula is at the bottom of the graphic.
Thanks for reading. Stay warm.