Monday, January 23, 2012
Quick Changes in the Progressive Pattern
Strong low pressure just east of Lake Superior continues to cause brisk winds across the Stateline early this evening. The wind will slowly ease up, but it will remain cloudy for most of the night. The overnight low will be in the mid to upper teens. Canadian high pressure will settle into the area on Tuesday. It will be chilly with highs around 27 degrees, but it will become mostly sunny in the afternoon. It will be cold overnight on Tuesday night with a low near 10 degrees under partly cloudy skies. High pressure will shift to the east on Wednesday, the wind will shift to the south,and temperatures will recover into the low 30's under partly sunny skies. On Thursday, the next fast moving Pacific system to affect the area, will push through in morning. It will have little affect on the weather across northern Illinois. Skies will become mostly sunny after frontal passage, and high temperatures will be in the middle 30's. A large sprawling type of Pacific high will nudge into the Pacific northwest on Friday, it will be partly sunny here with a high again in the middle 30's. Low pressure will intensify over James Bay in Canada by early Saturday. The large Pacific high will be centered over the Rocky Mountains, and a trough of low pressure will sweep across Wisconsin and Illinois early in the day. The circulation and pressure gradient set up between the high to the west and the low to the north will cause a gusty northwesterly wind to develop tapping some colder Canadian air. Temperatures by early Sunday will be in the low teens, and the high on Sunday afternoon will only reach the low 20's. Another in a series of fast moving systems will approach on Sunday night and Monday warming temperatures a bit, and bringing a chance of snow back to northern Illinois.