Ontario, CA

Weather Underground Forecast for Monday, May 21, 2012.

Coastal showers, bands of heavy rain and windy weather will continue to brush the coasts of Georgia and the Carolinas on Monday as Tropical Storm Alberto lingers offshore throughout the day. In addition to rain and wind, dangerous surf conditions and rip currents will remain possible along the coasts of Georgia and South Carolina through Monday. Expect little change in strength in this system before it accelerates northeastward by Monday night into Tuesday. Areas from Georgia through the Outer Banks of North Carolina should continue to monitor the progress of Alberto. For more information on Tropical Storm Alberto, please visit http://www.wunderground.com/tropical.

To the north of Alberto, another disturbance will move toward the Mid-Atlantic coast with unsettled weather. Onshore winds associated with this system will spread moisture inland, allowing scattered showers to form from areas of southern New York and eastern Pennsylvania down into North Carolina.

Behind this activity, a cold front with waves of low pressure extending from the Upper Great Lakes through the Southern Plains will move eastward with active weather. Rain and strong storms will form ahead of the system from the Upper Great Lakes through the Ohio and Tennessee Valleys and into the Southern Plains. The Upper Great Lakes and Eastern Valleys will also see some relief from Sunday's heat as the system moves through with significantly cooler temperatures on Monday and Tuesday. To the south, hot daytime highs will continue across the Deep South as temperatures reach into the upper 80s and 90s on Monday.

In the West, an occluded front will reach the Pacific Northwest with another batch of light to moderate showers. To the south, temperatures across the Desert Southwest will climb back into the 100 to near 110 degree range Monday afternoon. An Excessive Heat Watch remains in effect for areas of southeastern California and southwestern Arizona.