The most significant winter storm during January started as a surge of warm advection, followed by a strong trough through the southern Rockies on Friday, January 17. A period of moderate to heavy snowfall swept across the area, accompanied by southerly winds gusting to 35 to 45 mph. Snowfall then tapered off to a period of light freezing rain and freezing drizzle into the evening hours, before changing back to snow. By late evening and early in the overnight, winds transitioned to northwest and increased to 35 to 45 mph, with gusts of 50 to 60 mph common as low pressure intensified across Iowa. Strong winds persisted most of Saturday as the area of low pressure moved slowly toward the western Great Lakes. Most areas received between 4 and 8 inches of snowfall as well as a glaze of ice, with just shy of a quarter inch of ice in the Sioux City area.

Blizzard in LYON, IOWA
From 17-JAN-20 07:00:00 to 18-JAN-20 14:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 45 mph at Luverne and 35 mph at Doon.  Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 6.1 inches at Rock Rapids.

Blizzard in SIOUX, IOWA
From 17-JAN-20 06:00:00 to 18-JAN-20 14:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning of January 18 reaching 47 mph at Hawarden and 44 mph at Alton.  Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 6.1 inches at Orange City, 5.9 inches at Sioux Center, 5.1 inches at Rock Valley and 4.5 inches at Hawarden.

Blizzard in PLYMOUTH, IOWA
From 17-JAN-20 06:00:00 to 18-JAN-20 12:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning of January 18 reaching 47 mph at Le Mars.  Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 5.7 inches at Remsen, 5.2 inches at Le Mars and 5.0 inches at Akron.

Blizzard in WOODBURY, IOWA
From 17-JAN-20 05:30:00 to 18-JAN-20 08:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a tenth to two tenths of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning of January 18 reaching 58 mph at Sioux City.  Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 5.2 inches at Sioux City and 4.4 inches at Holly Springs.

Blizzard in O'BRIEN, IOWA
From 17-JAN-20 07:30:00 to 18-JAN-20 16:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 52 mph at Sheldon. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 7.3 inches at Sanborn, 6.1 inches at Primghar and 5.8 inches at Sheldon.

Blizzard in CHEROKEE, IOWA
From 17-JAN-20 07:00:00 to 18-JAN-20 14:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 38 mph at Cherokee. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 6.0 inches at Cherokee and 4 miles north of Cleghorn.

Blizzard in IDA, IOWA
From 17-JAN-20 05:30:00 to 18-JAN-20 10:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 52 mph at Storm Lake and 38 mph at Cherokee. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 4.5 inches at Holstein and 4.2 inches 3 miles northeast of Battle Creek.

Blizzard in BUENA VISTA, IOWA
From 17-JAN-20 07:30:00 to 18-JAN-20 15:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 52 mph at Storm Lake and 43 mph near Truesdale. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 7.9 inches 4 miles east of Sioux Rapids.

Blizzard in OSCEOLA, IOWA
From 17-JAN-20 07:00:00 to 18-JAN-20 16:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 48 mph 2 miles northeast of Sibley and 37 mph at Ocheyedan.  Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 7.0 at Sibley.

Blizzard in CLAY, IOWA
From 17-JAN-20 08:00:00 to 18-JAN-20 16:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 53 mph at Spencer. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 7.6 inches at Spencer and 7.0 inches 3 miles west northwest of Everly.

Blizzard in DICKINSON, IOWA
From 17-JAN-20 07:30:00 to 18-JAN-20 16:00:00 (CST-6)
Reported by: COOP Observer

A period of heavy snowfall with winds gusting to 30 to 40 mph moved through during the morning and early afternoon of January 17, before tapering to several hours of freezing drizzle. Ice accumulations were generally a glaze to a tenth of an inch, before precipitation changed back to snow in the evening. Winds then picked up from the northwest, with peak wind gusts during the morning reaching 43 mph at Lake Park. Combined with snowfall and previous snow, winds produced numerous hours with visibility of around one-quarter mile or less, with travel not recommended. Total snowfall reached 7.7 inches 4 miles west of Milford, 6.2 inches at Lake Park and 5.6 inches at Spirit Lake.