A major storm will gather strength and moisture this weekend and is forecast to deliver drenching rain and gusty thunderstorms to the Plains.
A storm bringing cooler air and spotty showers and thunderstorms to California at midweek is projected to swing inland over the Southwest by the end of the week.
The storm will use the Four Corners region as a command post to gather a fleet of moisture from the tropical Pacific and the Gulf of Mexico.
Downpours and flash flooding are forecast to drench isolated areas of the Southwest Wednesday into Friday.
The moisture will then shift eastward onto the Great Plains in the form of more broad areas of rain.
As a result, there is the potential for an inch or two of rain, and locally more, to fall on needy areas of Kansas, Nebraska and other Plains states beginning Friday and continuing into the weekend.
Some of the rain will fall on recently planted winter wheat areas.
According to Expert Senior Meteorologist Brett Anderson, "The storm is moving fast; as a result, we don't expect excessive rain and flooding to occur over a broad area."
Like many storms which form in this area of the United States and move northeastward, some of the energy released will not only be in the form of drenching rain. Severe weather is forecast.
Because of the dynamic nature of the storm, there is the risk of incidents of damaging wind gusts, large hail and at least a few tornadoes with the event.
According to Severe Weather Expert Henry Margusity, "Saturday is likely to be the peak of the severe weather with the storm system, but we are likely to have some locally dangerous storms late Friday over the central and southern High Plains."
The worst of the storms Saturday may focus within the zone from eastern Oklahoma to southwestern Wisconsin.
The storm will have its cold side too.
Heavy snow is likely to fall on the high country and perhaps some ski areas from part of the Sierra Nevada to the Wasatch to the Colorado Rockies late in the week.
As the storm moves northeastward, portions of central Ontario and Quebec could also be on the receiving end of heavy snow from the storm later this weekend.
The details of the rain, thunderstorms and snow from the storm system will unfold as the week progresses.
While rain and snow from this storm will avoid the Northwest, a different storm from the Pacific is forecast to begin a spell of wet weather and high country snow beginning late this week.
The track of the storm will rout out a fresh batch of cold air in the East, paving the way for perhaps a week or more of above-normal temperatures starting around Sunday. However, this is not before some of the lowest temperatures of the season occur with the risk of a killing frost and freeze Friday night into Saturday morning.
Showers and thunderstorms will return to the Southwest late this week and could reach part of California.
The late-season swelter will continue along much of the Atlantic Seaboard through the week as tens of millions head back to school and work.
An area of low pressure will bring a threat of heavy rain and flooding to parts of southern Europe through the middle of the week.
Life-threatening flash flooding and mudslides will occur across northeastern Mexico as Dolly moves ashore.
Following a warm, humid start for the first days of September, lower humidity and more pleasant conditions will return to the Pittsburgh area.
A cold front swinging into the Northeast will bring the threat of severe weather to part of the region on Tuesday afternoon.
Mecca, CA (1950)
126 degrees - highest ever for U.S. in Sept.
East Coast (1775)
Matecumbe Key, FL (1935)
Labor Day Hurricane hit Florida. Pressure at Matecumbe Key dipped to 26.35"/892.3 mb. Most intense hurricane ever to hit the U.S. with 200-mph wind. Tide of 15 feet; 408 dead.