A Pacific storm is bringing areas of low elevation rain, moderate to heavy mountain snow, and high winds to the Northwest. Strong Santa Ana winds and very dry conditions are producing elevated to critical fire weather conditions in southern California. Isolated strong to severe thunderstorms are possible through early Wednesday morning across parts of northeast Texas into western Tennessee. Read More >
Overview
Radar Overview | Severe Weather Reports | Rainfall Climatology - Sioux Falls |
Flooding/Photos
Major to record flooding was observed across the region due to the nearly 4 to 8 inches of rainfall. Here is a closer look at a few of the more active rivers across the area, along with flooding impacts observed in many sites.
Hydrographs
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Little Sioux Overview | Floyd River Overview | Record Alton Hydrograph | Linn Grove Hydrograph |
Flooding Impact Photos
Severe Weather:
Severe Weather Photos
Here's a collection of severe weather and tornado related photos from September 18-21, 2018. A brief touchdown of an EF-1 tornado was confirmed in Superior, Iowa late in the afternoon hours of September 20. An observation site near Superior Ethanol measured a 99 mph wind as the tornado moved through.
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Superior Ethanol (Photo: Mike Ehret) | VFW Building (Photo: Mike Ehret) | Tree Damage (Photo: Mike Ehret) | VFW Damage (Photo: Mike Ehret) |
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Superior Ethanol (Photo: Mike Ehret) | Superior Ethanol (Photo: Mike Ehret) | Superior, IA (Photo: Mike Ehret) | Superior, IA (Photo: Mike Ehret) |
Tornadoes:
Tornado - Superior, IA
Track Map ![]()
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The Enhanced Fujita (EF) Scale classifies tornadoes into the following categories:
EF0 Weak 65-85 mph |
EF1 Moderate 86-110 mph |
EF2 Significant 111-135 mph |
EF3 Severe 136-165 mph |
EF4 Extreme 166-200 mph |
EF5 Catastrophic 200+ mph |
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Storm Reports:
Here's an overview of severe weather and flooding reports from September 18-21, 2018. A brief touchdown of an EF-1 tornado was confirmed in Superior, Iowa late in the afternoon hours of September 20. An observation site near Superior Ethanol measured a 99 mph wind as the tornado moved through.
Rain Reports
Here is a closer look at rainfall reports across the Tri-State area during the September 18-21, 2018 time frame. In many locations, this heavy rainfall approached a top 5 accumulations for both a 24 hour period and 2 day rainfall period. This rainfall has also pushed many locations towards the top of the list for year to date and yearly rainfall accumulations.
Storm Total Accumulations September 18-21, 2018 |
Climatological Look At Heavy Rainfall | ||
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