With yet another sign that winter is well on its way, a blast of cold Canadian air will arrive in the northern Plains this week, accompanied by snow in some areas.
Temperatures will plunge by more than 30 degrees in the wake of a cold front today and tonight as it shifts from the northern Rockies into the Plains.
A wave of low pressure riding along the front will provide enough moisture to cause snowflakes to fly from Wyoming and Colorado into parts of Nebraska and South Dakota tonight.
In some cities such as Cheyenne, Denver, Scottsbluff and Rapid City, it could be enough to cause a slushy accumulation.
While the snow will only fall over a window of about six hours after the cold air arrives, the rapid drop in temperature to near freezing could support accumulation on some road surfaces.
Even major interstates such as I-25, I-76 and I-80 could become snow covered for a time. The lack of sunshine at night could help this possibility come to fruition more easily.
A small area from northern Colorado, southeastern Wyoming and western Nebraska looks to bear the brunt of this quick-moving snow event, with up to 6 inches not out of the question.
Lighter slushy accumulations can be expected in places like Denver, Scottsbluff and Rapid City after a changeover from rain.
As the cold air expands toward the Midwest, snowflakes could even fly for a brief time late on Wednesday night and early on Thursday toward central Nebraska and eastern South Dakota, including Sioux Falls.
In these areas, little if any accumulation is anticipated.
Yet another round of light snow looks to sweep across the central Rockies on Thursday into Thursday night, perhaps whitening the ground once again in places such as Cheyenne and Denver.
Combined with even colder temperatures, below freezing for an extended time in most areas, icy travel will become a distinct possibility, especially for Thursday evening's and Monday morning's commute.
Of course, as the weather usually goes in Denver this time of year, temperatures will likely warm dramatically by the weekend, heading back toward the 60-degree mark.
Hawaii will escape the worst, but not all of Guillermo's impacts as the tropical storm passes north of the islands Wednesday through Thursday.
A line of violent thunderstorms tore across Massachusetts, including the Boston area, Tuesday afternoon. Isolated severe thunderstorms will continue into Tuesday evening.
The Northeast will catch a break from heat and humidity for the remainder of the week.
Super Typhoon Soudelor in the western Pacific Ocean will remain a powerful tropical cyclone this week eventually threatening Taiwan and eastern China.
An area of low pressure spinning off the coast of the Carolinas is attempting to obtain some tropical characteristics.
Public officials are in the process of eliminating Naegleria Fowleri, a brain-eating amoeba, from two drinking water supplies in Louisiana.
Casper, WY (1990)
A total of 0.84" of rain. The normal rainfall for all of August is 0.63".
Alexandria, VA (1992)
80 mph wind gust from a thunderstorm.
Flathead Lake, MT (1995)
5-6 foot waves from a distant thunderstorm damaged boats, sea walls, and docks.