In the West, scattered showers cover northern California and the Intermountain region. Some of the heaviest rain and snow showers are occurring in northern California, where spring precipitation is slowing fieldwork but has improved water-supply prospects.

On the Plains, winter wheat development and spring fieldwork activities remain well ahead of the normal pace. However, developing showers are curtailing fieldwork in some areas. Despite some overnight rainfall on the southern High Plains, drought remains a significant concern.

In the Corn Belt, freeze warnings are in effect again this morning. A high-pressure system currently centered over Illinois and Indiana has resulted in clear, cool, near calm conditions across much of the Midwest. Producers continue to monitor fruit crops for signs of freeze injury, while there is less concern for winter wheat due to the stage of development and for corn due to minimal Midwestern emergence.

In the South, cool, dry weather prevails. Early today, widespread, generally light freezes in Kentucky and Tennessee may have threatened some fruit crops, headed winter wheat, and emerged corn. Most of the remainder of the South appears to have escaped with minimal impacts from the cool spell.

Outlook: During the next 5 days, an active weather pattern will result in as much as 1 to 3 inches of rain, with locally higher amounts, from the eastern Plains into the Mississippi Valley and the Great Lakes region. The West will also receive beneficial precipitation, but unfavorably dry weather will prevail on the southern High Plains and across the Southeastern and Mid-Atlantic States. Very cool weather will cover the West, but the eastern half of the U.S. will experience a rapid, late-week warming trend. The NWS 6- to 10-day outlook for April 17-21 calls for above-normal temperatures across the Southeastern and Mid-Atlantic States and much of the West, while coolerthan- normal conditions will prevail in the central one-third of the U.S. Meanwhile, above-normal precipitation in much of the eastern one-third of the nation and the Northwest will contrast with drier-than-normal weather across the Plains and Southwest.