Freezing Dates

Using the NWS COOP data archive, significant dates relating to fall are extracted and presented on this page. The specific dates are the first occurance of that temperature and may have occured again in subsequent years.
The "Record Lows" columns show the first fall occurance of a low temperature. The "Average Lows" column shows when certain climatological thresholds are surpassed in the fall.

COOP Site: Record Lows: Average Lows:
Temp <= 32°F Temp <= 28°F Below 40°F Below 32°F Below 28°F
Temp: Date: Temp: Date:
BATTLE CREEK 3NE 32 {2014}-09-13 24 {2012}-09-23 10-04 10-17 10-31
SIBLEY-5-NNE 30 {1950}-08-20 23 {1955}-09-11 10-07 10-26 11-03
CHEROKEE 31 {1974}-09-03 27 {1955}-09-11 10-07 10-27 11-07
ROCK-RAPIDS 31 {1974}-09-03 26 {1894}-09-10 10-07 10-24 11-05
Estherville 4E 32 {1924}-09-09 27 {1929}-09-18 10-07 10-27 11-06
LITTLE SIOUX 2NW 31 {2007}-09-15 27 {2012}-09-23 10-08 10-25 11-01
HOLSTEIN 5 NNW 30 {2020}-10-02 28 {2019}-10-12 10-08 10-15 10-27
Spencer Area -1 {2010}-08-16 -1 {2010}-08-16 10-09 10-27 11-08
Spencer Airport -1 {2010}-08-16 -1 {2010}-08-16 10-09 10-26 11-10
Elkader 6SSW (Osborn) 32 {1893}-08-29 0 {2002}-09-02 10-09 10-28 11-10
Spencer 31 {1974}-09-03 28 {2007}-09-15 10-09 10-27 11-08
SIOUX-RAPIDS 31 {1974}-09-03 28 {1991}-09-19 10-09 10-27 11-07
SWEA CITY 4 W 32 {1974}-09-03 26 {1974}-09-22 10-09 10-29 11-10
MASON CITY MUNICIPAL AP 31 {2014}-09-13 26 {2011}-09-15 10-09 10-28 11-07
MASON-CITY 30 {1915}-08-30 28 {1923}-09-14 10-10 10-28 11-09
DECORAH-2-N 32 {1915}-08-30 28 {1946}-09-02 10-10 11-01 11-11
CASCADE 32 {2023}-08-31 28 {1953,1974}-09-22 10-10 11-03 11-11
FAYETTE 32 {1949}-09-01 27 {1902}-09-12 10-10 10-28 11-10
POCAHONTAS 31 {1946}-09-02 27 {1929}-09-18 10-10 10-28 11-10
SANBORN 32 {1974}-09-03 25 {1929}-09-18 10-10 10-27 11-07
Milford 32 {1974}-09-03 28 {1929}-09-18 10-10 10-31 11-08
Oelwein Area 28 {1955}-09-11 28 {1955}-09-11 10-10 11-02 11-11
ESTHERVILLE MUNICIPAL AP 31 {2014}-09-13 28 {2007}-09-15 10-10 10-26 11-07
NORTHWOOD 32 {1953}-09-13 28 {1929}-09-18 10-10 10-28 11-08
STANLEY 31 {2014}-09-13 26 {2012}-09-23 10-11 10-27 11-01
SIOUX CITY ANG 31 {2012}-09-23 20 {2004}-10-02 10-11 10-27 11-10
IOWA-FALLS 31 {1915}-08-30 28 {1894}-09-18 10-12 11-01 11-10
HAMPTON-2-NW 32 {1955}-09-11 28 {1955}-09-12 10-12 11-01 11-10
Le Mars 31 {1955}-09-11 28 {1902}-09-12 10-12 10-29 11-08
WEBSTER-CITY 30 {1955}-09-11 25 {1929}-09-18 10-12 10-28 11-10
FOREST-CITY 31 {1949}-09-01 27 {1929}-09-18 10-13 10-28 11-10
NEW-HAMPTON 28 {1949}-09-01 28 {1949}-09-01 10-13 11-01 11-10
Emmetsburg 0 {2005}-09-03 0 {2005}-09-03 10-13 11-01 11-10
Waterloo Area 32 {1917}-09-11 28 {1929}-09-18 10-13 11-02 11-11
WATERLOO 32 {1917}-09-11 28 {1929}-09-18 10-13 11-02 11-10
MARSHALLTOWN 31 {1955}-09-12 28 {1896}-09-20 10-13 11-02 11-11
Iowa - Northwest Climate Division 30 {1902}-09-12 26 {1918}-09-20 10-13 10-31 11-10
GRUNDY-CENTER 32 {1902}-09-12 28 {1929}-09-18 10-13 11-02 11-11
MANCHESTER-2 32 {2014}-09-13 27 {1984}-09-16 10-13 11-02 11-11
OSAGE 30 {1949}-09-14 28 {1929}-09-18 10-13 11-01 11-10
OELWEIN 1E 32 {2011}-09-15 28 {2012}-10-05 10-13 10-28 11-11
WAUKON 32 {1937,2011}-09-16 25 {1942}-09-25 10-13 11-02 11-10
LOWDEN 32 {2014}-09-13 26 {2012}-09-24 10-14 11-01 11-11
MARSHALLTOWN MUNICIPAL AP 30 {2007}-09-15 27 {2012}-09-23 10-14 10-31 11-11
AMES MUNICIPAL AP 31 {2007}-09-15 27 {2003}-09-30 10-14 10-31 11-11
MAPLETON NO. 2 31 {1955}-09-11 27 {1991}-09-19 10-15 11-02 11-10
DAVENPORT WFO 30 {2012}-09-23 27 {2012}-10-05 10-15 10-29 11-11
ANAMOSA 3 SSW 30 {2012}-09-24 26 {2015}-10-17 10-15 10-29 11-12
ATLANTIC-1-NE 30 {1893}-09-02 28 {1902,1955}-09-12 10-16 11-01 11-10
SAC-CITY 32 {1974}-09-03 28 {1918}-09-20 10-16 11-01 11-11
CARROLL-2-SSW 28 {1974}-09-03 28 {1974}-09-03 10-16 10-28 11-10
FORT-DODGE 32 {1974}-09-03 27 {1902}-09-13 10-16 11-02 11-11
SIOUX CENTER 2 SE 31 {1974}-09-03 24 {1991}-09-19 10-16 10-28 11-10
Ida Grove Area 32 {1974}-09-03 27 {1918}-09-20 10-16 10-28 11-10
PRIMGHAR 30 {1902}-09-12 25 {1901}-09-18 10-16 10-31 11-10
CHARLES-CITY 32 {1902,1955}-09-12 28 {1991}-09-20 10-16 11-02 11-11
Dubuque Airport 32 {2007}-09-15 28 {1956}-09-20 10-16 11-03 11-13
RATHBUN DAM 0 {2012}-08-09 0 {2012}-08-09 10-17 11-07 11-21
JEFFERSON 32 {1893}-08-29 28 {1929}-09-18 10-17 11-02 11-11
ALLISON 32 {1915}-08-30 28 {1926}-09-25 10-17 11-02 11-11
BELLEVUE-L-AND-D-12 32 {1986}-08-30 28 {1974,1995}-09-23 10-17 11-06 11-21
Postville 32 {1919}-09-02 20 {1918}-09-21 10-17 11-02 11-11
ALGONA 29 {1893}-09-02 27 {1929}-09-18 10-17 11-01 11-10
OAKLAND-2-E 32 {1974}-09-03 28 {1995}-09-22 10-17 11-03 11-11
GRINNELL-3-SW 31 {1976}-09-10 27 {1991}-09-20 10-17 11-02 11-11
MAQUOKETA-2-W 31 {1917}-09-11 28 {1983}-09-23 10-17 11-02 11-12
BELLE-PLAINE 31 {1917}-09-11 28 {1916,1929}-09-18 10-17 11-03 11-12
TOLEDO 31 {1917}-09-11 27 {1896}-09-20 10-17 11-02 11-11
Boone 32 {1975}-09-12 27 {1929}-09-18 10-17 11-02 11-11
Iowa Drought Region 2 - Northcentral 32 {1902}-09-12 27 {1913}-09-22 10-17 11-02 11-11
GUTHRIE-CENTER 31 {1902}-09-12 28 {1991}-09-19 10-17 11-02 11-11
LOGAN 30 {1902}-09-12 28 {1902}-09-13 10-17 11-02 11-11
SPIRIT LAKE 31 {1902}-09-12 28 {1929}-09-18 10-17 11-01 11-10
CORNING 32 {1902}-09-12 27 {1983}-09-21 10-17 11-03 11-13
CHARITON 32 {1955}-09-12 28 {1918,1991}-09-20 10-17 11-05 11-21
PERRY 32 {1955}-09-12 27 {1929}-09-18 10-17 11-02 11-11
AUDUBON 30 {1902,1955}-09-12 27 {1896}-09-19 10-17 11-01 11-10
Iowa - West Central Climate Division 31 {1902}-09-12 28 {1918}-09-20 10-17 11-02 11-11
Iowa Drought Region 1 - Northwest 30 {1902}-09-12 25 {1918}-09-20 10-17 11-01 11-10
STORM-LAKE-2-E 32 {1902}-09-12 28 {1929}-09-18 10-17 11-01 11-10
Iowa - Northeast Climate Division 32 {1902}-09-13 26 {1926}-09-26 10-17 11-02 11-11
SIOUX-CITY-WSO-AP 30 {1902}-09-13 25 {1995}-09-22 10-17 11-02 11-10
Sioux City Area 30 {1902}-09-13 25 {1995}-09-22 10-17 11-02 11-10
Iowa - North Central Climate Division 32 {1902,2014}-09-13 28 {1929}-09-18 10-17 11-02 11-10
Ames Area 31 {1902}-09-13 26 {1918}-09-21 10-17 11-02 11-11
VINTON 32 {1902,1953}-09-13 28 {1982}-09-21 10-17 11-03 11-12
Cedar Rapids Airport 31 {2007}-09-15 28 {2012}-09-24 10-17 11-05 11-13
MUSCATINE 2N 27 {2003}-10-02 27 {2003}-10-02 10-17 11-11 11-22
WILLIAMSBURG 32 {1917}-09-11 28 {1991}-09-20 10-18 11-03 11-12
DENISON 29 {1902}-09-12 21 {1918}-09-21 10-18 11-02 11-11
CLARINDA 31 {1902}-09-13 28 {1918}-09-21 10-18 11-02 11-19
AMES-8-WSW 31 {1902}-09-13 26 {1918}-09-21 10-18 11-02 11-12
Cedar Rapids Area 31 {2007}-09-15 28 {2012}-09-24 10-18 11-03 11-19
Creston 31 {1924}-09-15 28 {1991}-09-19 10-18 11-03 11-13
RED-OAK 32 {1940}-09-11 28 {1995}-09-22 10-19 11-03 11-21
Iowa Drought Region 4 - Southwest 32 {1902}-09-12 26 {1942}-09-28 10-19 11-05 11-19
WINTERSET 31 {1955}-09-12 26 {1896}-09-20 10-19 11-07 11-21
SIGOURNEY 32 {1902}-09-13 25 {1913}-09-21 10-19 11-08 11-22
Iowa Average 32 {1902}-09-13 24 {1942}-09-28 10-19 11-03 11-11
OSKALOOSA 31 {1902}-09-13 27 {1991}-09-20 10-19 11-08 11-21
MOUNT-AYR 32 {1902}-09-13 28 {1991}-09-19 10-19 11-05 11-19
AMES 5 SE 32 {1902}-09-13 28 {1926}-09-26 10-19 11-04 11-20
Iowa Drought Region 3 - Northeast 32 {1902}-09-13 27 {1926}-09-26 10-19 11-03 11-12
Iowa City 32 {1923}-09-14 28 {1916}-09-18 10-19 11-06 11-21
OSCEOLA-3-WSW 31 {2007}-09-15 28 {1974}-09-22 10-19 11-07 11-21
Dubuque Area 32 {2007}-09-15 28 {1956}-09-20 10-19 11-05 11-21
SHENANDOAH-1-NE 32 {1937}-09-16 28 {1918}-09-20 10-19 11-07 11-21
GREENFIELD 32 {1981}-09-17 27 {1913}-09-22 10-19 11-08 11-21
Iowa - Central Climate Division 31 {1929}-09-18 28 {1913}-09-22 10-19 11-03 11-11
BEACONSFIELD 27 {1991}-09-19 27 {1991}-09-19 10-19 11-05 11-20
Allerton 31 {1991}-09-19 27 {1913}-09-22 10-19 11-08 11-21
IOWA CITY MUNICIPAL AP 32 {1991}-09-20 26 {1995}-09-23 10-19 11-07 11-21
Donnellson 31 {1991}-09-20 25 {1942}-09-28 10-19 11-10 11-22
CLINTON-1 31 {1902}-09-13 28 {1928}-09-25 10-20 11-09 11-22
CEDAR-RAPIDS-1 32 {2007}-09-15 24 {1926}-09-26 10-20 11-06 11-21
Iowa - East Central Climate Division 32 {1929}-09-18 28 {1926}-09-26 10-20 11-06 11-21
NEWTON 32 {1929}-09-18 23 {1942}-09-28 10-20 11-06 11-21
DES MOINES WSFO-JOHNSTON 31 {1999}-09-21 28 {2004}-10-02 10-21 11-10 11-12
FAIRFIELD 32 {1917}-09-11 28 {1918}-09-21 10-24 11-08 11-22
KEOSAUQUA 31 {1917}-09-11 28 {1916}-09-18 10-24 11-10 11-22
COLUMBUS JUNCT 2 SSW 31 {1955}-09-12 28 {1991}-09-20 10-24 11-08 11-22
WASHINGTON 30 {1902}-09-13 28 {1983}-09-23 10-24 11-08 11-21
Iowa - Southwest Climate Division 32 {1902}-09-13 26 {1942}-09-28 10-24 11-08 11-21
Ottumwa 32 {2007}-09-15 23 {1942}-09-28 10-24 11-09 11-22
GUTTENBERG-L-AND-D-10 32 {1973}-09-18 25 {1942}-09-28 10-24 11-07 11-21
Lamoni 32 {1901}-09-18 27 {1942}-09-28 10-24 11-08 11-21
Des Moines Area 31 {1995}-09-22 26 {1942}-09-28 10-24 11-08 11-21
Des Moines Airport 31 {1995}-09-22 26 {1942}-09-28 10-24 11-08 11-21
CENTERVILLE 31 {1913}-09-13 28 {1913}-09-22 10-25 11-10 11-22
MOUNT-PLEASANT 32 {1902}-09-13 28 {1942}-09-24 10-25 11-10 11-22
Iowa - Southeast Climate Division 32 {1896}-09-20 25 {1942}-09-28 10-25 11-09 11-22
DUBUQUE-LOCK-AND-DAM 31 {1956}-09-20 24 {1899}-09-30 10-25 11-10 11-22
MUSCATINE 29 {1991}-09-20 23 {1942}-09-28 10-25 11-10 11-21
Iowa Drought Region 5 - Southeast 32 {1918}-09-21 24 {1942}-09-28 10-25 11-08 11-21
Iowa - South Central Climate Division 32 {1918}-09-21 25 {1942}-09-28 10-25 11-08 11-21
LAMONI -1 {2011,2012}-08-07 -1 {2011,2012}-08-07 10-26 11-11 11-21
Burlington Airport 30 {1918}-09-18 25 {1942}-09-28 10-27 11-10 11-24
Fort Madison 32 {1913}-09-22 26 {1942}-09-28 10-27 11-11 11-24
BURLINGTON 32 {1984}-09-26 28 {1974}-10-02 10-28 11-11 11-27
Le Claire L&D 14 32 {1942}-09-26 28 {1942}-09-28 10-28 11-11 11-23