GOES-10 Science Test
Weather Synopsis - 06 April/12UTC to 07 April/12UTC 1998
A ridge aloft was situated across the southern Mississippi valley region, with broad troughs over the western U.S. and also over the Canadian Maritimes. A negatively-tilted shortwave moving through the base of the western U.S. trough progressed across the southern Rockies into the southern High Plains. A strong (130-150 knot) jet accompanied this feature; this jet then continued eastward, curving anticyclonically across the Southeast.
At the surface, rapid cyclogenesis occurred over the central Plains, and a dryline stretched southwestward from this low across Kansas and the Oklahoma and Texas panhandle regions. A warm front began to lift northward across eastern Kansas into eastern Nebraska and southern Iowa, as strong southerly flow set up from the Gulf of Mexico into the southern and central Plains.
Convection was widespread across the central and southern Plains. Storm development was focused along the dryline in Kansas, Oklahoma, and Texas, as well as along the warm front lifting northward into Nebraska and Iowa. Three weak tornadoes were reported in northwest Iowa. Large hail was reported in Kansas (2.00 inch diameter), Oklahoma (1.75 inch), and Iowa (1.50 inch). Several reports of smaller hail were received across Minnesota, Nebraska, Colorado, Texas, and Arkansas. Wind damage was reported across Oklahoma and Kansas (61 mph gusts). Heavy rains fell over parts of northern and central Plains -- new daily rainfall records were established for both 06 and 07 April at Grand Island, Nebraska (0.73 and 1.93 inches) and Hastings, Nebraska (0.87 and 1.74 inches, respectively).
Lighter rainfall was widespread from California to the Rockies and northern Plains. Mountain snows were noted from the California Sierras to the Black Hills of South Dakota (amounts as high as 6-11 inches were reported in Wyoming and Colorado). Light snow (1-5 inches) fell over parts of North Dakota and Nebraska.