National Weather Service United States Department of Commerce

Precipitation in the Pacific Northwest into the Northern Rockies; Bering Sea Storm in Alaska

A Pacific storm will bring rain and high elevation snow from the Pacific Northwest into the Northern Rockies. A series of storms are expected to move through the Bering Sea bringing strong winds, heavy precipitation, and elevated water levels from the West Coast to northern Alaska. Read More >

Cyclic Supercell: A thunderstorm that undergoes cycles of intensification and weakening (pulses) while maintaining its individuality. Cyclic supercells are capable of producing multiple tornadoes (i.e., a tornado family) and/or several bursts of severe weather.  NOAA Technical Memorandum NWS SR-145: A Comprehensive Glossary of Weather Terms For Storm Spotters.

Supercell: An often dangerous storm that consists primarily of a single, quasi-steady rotating updraft, which persists for a period of time. The supercell typically has a very organized internal structure that enables it to propagate continuously. It may exist for several hours and usually forms in an environment with strong vertical wind shear. Severe weather often accompanies supercells, which are capable of producing high winds, large hail, and strong, long-lived tornadoes.  American Meteorological Society: Glossary of Meteorology

Another more recent example of a cyclic supercell storm was back on April 28th, 2002. One supercell storm produced SEVEN tornadoes across our county warning area. The first tornado occurred in Bollinger County, MO with subsequent tornadoes occurring further east in far southern Illinois and western Kentucky.

2002 outbreak