GOES-10 Science Test
Weather Synopsis - 08 April/12UTC to 09 April/12UTC 1998


Synoptic Situation:

A broad upper level trough of low pressure covered much of the central US, with a closed low south of the Great Lakes. Another trough was located over the Gulf of Alaska region. A flat upper level ridge was situated along the east coast. The polar jet stream was located across the southern tier of states, with a 130 knot core from Texas into the Tennessee valley.

At the surface, an occluded low moved from eastern Iowa into northern Indiana and Ohio. A cold front associated with this low moved eastward across Texas and the Mississippi/Tennessee valley regions toward the southeastern US, while a warm front was draped across the mid-Atlantic region. In the western US, a weak low approached the Pacific Northwest, and a cold front weakened as it crossed the northern Rockies.

Weather Conditions:

Strong convection erupted across much of the southeastern US, including a significant outbreak of tornadoes across Alabama and Georgia. Most notable was the F5 tornado which affected a 21-mile path in Jefferson county Alabama (near Birmingham) - 31 deaths were attributed to this storm. Other tornadoes across Alabama and Georgia were responsible for an additional 7 deaths. Large hail (1.25 to 2.75 inches in diameter) were also reported across Arkansas, Alabama, Tennessee, and Georgia.

Precipitation was widespread across the eastern half of the US, with amounts of 1.0 - 2.5 inches over northern Florida, the Carolinas, and the Tennessee valley. Amounts of 0.5 - 1.0 inch were reported across the Ohio valley and southern Great Lakes regions. In the West, lighter precipitation amounts (less than 0.25 inch) were seen across northern California and the northern Rockies.