A weak trough of low pressure from MN into the southern Plains brought light south winds and increasing low level moisture into the region.  This resulted in the development of widespread dense fog beginnning during the evening of November 19, 2012 and lasting into much of November 20.  Other than a brief improvement in conditions during the early to mid afternoon, visibilities were frequently at or below 1/4 mile. According to KWWL-TV the dense fog contributed to a multi-vehicle accident at about 6 pm on November 20. The accident, which occurred on Highway 30 west of Cedar Rapids near the Benton/Linn county line, injured 2 motorists. About 9 miles of westbound traffic had to be re-routed while the accident was cleaned up.

Dense Fog in BENTON, IOWA
From 19-NOV-12 23:55:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in BUCHANAN, IOWA
From 19-NOV-12 22:55:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in DELAWARE, IOWA
From 20-NOV-12 00:10:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in CLINTON, IOWA
From 20-NOV-12 19:55:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in DES MOINES, IOWA
From 20-NOV-12 03:40:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Dense Fog in DUBUQUE, IOWA
From 20-NOV-12 08:38:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Dense Fog in CEDAR, IOWA
From 20-NOV-12 06:35:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in HENRY, IOWA
From 20-NOV-12 04:00:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in IOWA, IOWA
From 20-NOV-12 00:30:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in JACKSON, IOWA
From 20-NOV-12 09:00:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in JEFFERSON, IOWA
From 20-NOV-12 02:15:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in JOHNSON, IOWA
From 19-NOV-12 23:17:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Dense Fog in JONES, IOWA
From 20-NOV-12 06:35:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in KEOKUK, IOWA
From 20-NOV-12 01:15:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in LEE, IOWA
From 20-NOV-12 04:00:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in LOUISA, IOWA
From 19-NOV-12 22:00:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in MUSCATINE, IOWA
From 19-NOV-12 21:35:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in SCOTT, IOWA
From 20-NOV-12 17:22:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Dense Fog in VAN BUREN, IOWA
From 20-NOV-12 02:15:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in WASHINGTON, IOWA
From 20-NOV-12 02:00:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Dense Fog in LINN, IOWA
From 20-NOV-12 00:08:00 to 20-NOV-12 23:59:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

According to KWWL-TV the dense fog contributed to a multi-vehicle accident at about 6 pm on November 20. The accident, which occurred on Highway 30 west of Cedar Rapids near the Benton/Linn county line, injured 2 motorists. About 9 miles of westbound traffic had to be re-routed while the accident was cleaned up.