National Weather Service United States Department of Commerce

Back-to-Back Storms for the Center of the Nation

These storm systems will bring late season snow, sleet and ice for portions of the northern Plains, upper Midwest and Great Lakes region. Meanwhile, where temperatures are warmer, severe thunderstorms are expected for areas of the Mississippi Valley into the southern Plains. Furthermore, combination of windy and dry conditions will raise fire weather concerns for the southern High Plains. Read More >

12-hour helicity forecast

 

Figure 5: ETA 12 Hour Forecast of 300 K isentropic surface,
wind and relative humidity valid 1200 UTC May 12, 1997.

 

18-hour helicity forecast

 

Figure 6: ETA 18 Hour Forecast of 300 K isentropic surface,
wind and relative humidity valid 1800 UTC May 12, 1997.