Areas of active weather will continue along a long frontal boundary that will reach from the Mid-Atlantic Coast through the Southern Plains and into the Four Corners on Thursday.
A wave of low pressure along the western end of this system and a surge of moisture from the southwest will create more valley rain, high elevation snow and thunderstorms in the Southwest and the eastern Central Great Basin. Storms will spread into the Central and Southern Plains during the day. Meanwhile, flow associated with high pressure moving off the south Atlantic coast will spread moisture from the Gulf of Mexico northward into the Central Plains and Eastern Valleys. This moist flow will interact with portions of the front over these areas to produce rain and thunderstorms in these regions during the afternoon and evening. Storms in areas from northeastern Oklahoma and eastern Kansas into western through north central Missouri may turn severe with large hail. On the eastern end of this boundary, light to moderate rain showers are expected in the northern Mid-Atlantic.
Elsewhere in the East, high pressure will provide more fair and warm weather conditions to the Southeast as it moves off the south Atlantic coast.
In the West, an unseasonably cold trough of low pressure will provide more chilly and unsettled weather in the Northwest. The system will support more rain showers and snow with very low snow levels from the Pacific Northwest through the Northern Rockies. A disturbance associated with this trough will sag southeastward through the day, spreading precipitation into northern and central California as well as the Central Great Basin.
Temperatures in the Lower 48 states Wednesday ranged from a morning low of 5 degrees at Mt. Washington, N.H., to a high of 95 degrees at Childress, Texas.