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: |
| HOLSTEIN 5 NNW | 30 | {2020}-10-02 | 28 | {2019}-10-12 | 10-08 | 10-15 | 10-31 |
| BATTLE CREEK 3NE | 32 | {2014}-09-13 | 24 | {2012}-09-23 | 10-04 | 10-17 | 10-31 |
| ROCK-RAPIDS | 31 | {1974}-09-03 | 26 | {1894}-09-10 | 10-07 | 10-24 | 11-05 |
| LITTLE SIOUX 2NW | 31 | {2007}-09-15 | 27 | {2012}-09-23 | 10-08 | 10-25 | 11-11 |
| Spencer Airport | -1 | {2010}-08-16 | -1 | {2010}-08-16 | 10-07 | 10-26 | 11-10 |
| SIBLEY-5-NNE | 30 | {1950}-08-20 | 23 | {1955}-09-11 | 10-07 | 10-26 | 11-03 |
| ESTHERVILLE MUNICIPAL AP | 31 | {2014}-09-13 | 28 | {2007}-09-15 | 10-10 | 10-26 | 11-07 |
| Spencer Area | -1 | {2010}-08-16 | -1 | {2010}-08-16 | 10-09 | 10-27 | 11-08 |
| Mason City Area | 30 | {1915}-08-30 | 28 | {1923}-09-14 | 10-10 | 10-27 | 11-09 |
| Spencer | 31 | {1974}-09-03 | 28 | {2007}-09-15 | 10-09 | 10-27 | 11-08 |
| SANBORN | 32 | {1974}-09-03 | 25 | {1929}-09-18 | 10-10 | 10-27 | 11-07 |
| CHEROKEE | 31 | {1974}-09-03 | 27 | {1955}-09-11 | 10-07 | 10-27 | 11-07 |
| SIOUX-RAPIDS | 31 | {1974}-09-03 | 28 | {1991}-09-19 | 10-09 | 10-27 | 11-07 |
| Estherville 4E | 32 | {1924}-09-09 | 27 | {1929}-09-18 | 10-07 | 10-27 | 11-06 |
| 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 | 10-08 | 10-27 | 11-10 |
| Elkader 6SSW (Osborn) | 32 | {1893}-08-29 | 0 | {2002}-09-02 | 10-09 | 10-28 | 11-10 |
| Mason City | 30 | {1915}-08-30 | 28 | {1923}-09-14 | 10-10 | 10-28 | 11-09 |
| FOREST-CITY | 31 | {1949}-09-01 | 27 | {1929}-09-18 | 10-13 | 10-28 | 11-10 |
| 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 |
| SIOUX CENTER 2 SE | 31 | {1974}-09-03 | 24 | {1991}-09-19 | 10-14 | 10-28 | 11-10 |
| WEBSTER-CITY | 30 | {1955}-09-11 | 25 | {1929}-09-18 | 10-13 | 10-28 | 11-10 |
| Iowa Drought Region 1 - Northwest | 30 | {1902}-09-12 | 28 | {1991}-09-19 | 10-12 | 10-28 | 11-10 |
| Iowa - Northwest Climate Division | 30 | {1902}-09-12 | 26 | {1918}-09-20 | 10-12 | 10-28 | 11-10 |
| NORTHWOOD | 32 | {1953}-09-13 | 28 | {1929}-09-18 | 10-10 | 10-28 | 11-08 |
| MASON CITY MUNICIPAL AP | 31 | {2014}-09-13 | 26 | {2011}-09-15 | 10-09 | 10-28 | 11-07 |
| OELWEIN 1E | 32 | {2011}-09-15 | 28 | {2012}-10-05 | 10-13 | 10-28 | 11-12 |
| SWEA CITY 4 W | 32 | {1974}-09-03 | 26 | {1974}-09-22 | 10-09 | 10-29 | 11-10 |
| Le Mars | 31 | {1955}-09-11 | 28 | {1902}-09-12 | 10-12 | 10-29 | 11-08 |
| Milford | 32 | {1974}-09-03 | 28 | {1929}-09-18 | 10-13 | 10-31 | 11-08 |
| Ida Grove Area | 32 | {1974}-09-03 | 27 | {1918}-09-20 | 10-16 | 10-31 | 11-10 |
| PRIMGHAR | 30 | {1902}-09-12 | 25 | {1901}-09-18 | 10-16 | 10-31 | 11-10 |
| AMES MUNICIPAL AP | 31 | {2007}-09-15 | 27 | {2003}-09-30 | 10-14 | 10-31 | 11-11 |
| MARSHALLTOWN MUNICIPAL AP | 30 | {2007}-09-15 | 27 | {2012}-09-23 | 10-14 | 10-31 | 11-11 |
| DECORAH-2-N | 32 | {1915}-08-30 | 28 | {1946}-09-02 | 10-10 | 11-01 | 11-11 |
| IOWA-FALLS | 31 | {1915}-08-30 | 28 | {1894}-09-18 | 10-13 | 11-01 | 11-10 |
| NEW-HAMPTON | 28 | {1949}-09-01 | 28 | {1949}-09-01 | 10-13 | 11-01 | 11-11 |
| ATLANTIC-1-NE | 30 | {1893}-09-02 | 28 | {1902,1955}-09-12 | 10-16 | 11-01 | 11-11 |
| ALGONA | 29 | {1893}-09-02 | 27 | {1929}-09-18 | 10-16 | 11-01 | 11-10 |
| Emmetsburg | 0 | {2005}-09-03 | 0 | {2005}-09-03 | 10-13 | 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 | 11-01 | 11-10 |
| FORT-DODGE | 32 | {1974}-09-03 | 27 | {1902}-09-13 | 10-16 | 11-01 | 11-11 |
| HAMPTON-2-NW | 32 | {1955}-09-11 | 28 | {1955}-09-12 | 10-12 | 11-01 | 11-11 |
| STORM-LAKE-2-E | 32 | {1902}-09-12 | 28 | {1929}-09-18 | 10-17 | 11-01 | 11-10 |
| CHARLES-CITY | 32 | {1902,1955}-09-12 | 28 | {1991}-09-20 | 10-16 | 11-01 | 11-11 |
| SPIRIT LAKE | 31 | {1902}-09-12 | 28 | {1929}-09-18 | 10-17 | 11-01 | 11-10 |
| AUDUBON | 30 | {1902,1955}-09-12 | 27 | {1896}-09-19 | 10-16 | 11-01 | 11-10 |
| Iowa - North Central Climate Division | 32 | {1902}-09-13 | 28 | {1929}-09-18 | 10-13 | 11-01 | 11-10 |
| LOWDEN | 32 | {2014}-09-13 | 26 | {2012}-09-24 | 10-14 | 11-01 | 11-11 |
| OSAGE | 30 | {1949}-09-14 | 28 | {1929}-09-18 | 10-13 | 11-01 | 11-10 |
| WAUKON | 32 | {1937,2011}-09-16 | 25 | {1942}-09-25 | 10-13 | 11-01 | 11-10 |
| DAVENPORT WFO | 30 | {2012}-09-23 | 27 | {2012}-10-05 | 10-15 | 11-01 | 11-11 |
| ANAMOSA 3 SSW | 30 | {2012}-09-24 | 26 | {2024}-10-16 | 10-15 | 11-01 | 11-12 |
| 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 |
| Postville | 32 | {1919}-09-02 | 20 | {1918}-09-21 | 10-17 | 11-02 | 11-11 |
| GRINNELL-3-SW | 31 | {1976}-09-10 | 27 | {1991}-09-20 | 10-17 | 11-02 | 11-12 |
| WATERLOO | 32 | {1917}-09-11 | 28 | {1929}-09-18 | 10-13 | 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 | 11-02 | 11-12 |
| Waterloo Area | 32 | {1917}-09-11 | 28 | {1929}-09-18 | 10-13 | 11-02 | 11-11 |
| Oelwein Area | 28 | {1955}-09-11 | 28 | {1955}-09-11 | 10-10 | 11-02 | 11-11 |
| TOLEDO | 31 | {1917}-09-11 | 27 | {1896}-09-20 | 10-17 | 11-02 | 11-11 |
| MAPLETON NO. 2 | 31 | {1955}-09-11 | 27 | {1991}-09-19 | 10-15 | 11-02 | 11-10 |
| DENISON | 29 | {1902}-09-12 | 21 | {1918}-09-21 | 10-17 | 11-02 | 11-11 |
| GRUNDY-CENTER | 32 | {1902}-09-12 | 28 | {1929}-09-18 | 10-13 | 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 |
| MARSHALLTOWN | 31 | {1955}-09-12 | 28 | {1896}-09-20 | 10-13 | 11-02 | 11-11 |
| PERRY | 32 | {1955}-09-12 | 27 | {1929}-09-18 | 10-17 | 11-02 | 11-11 |
| Iowa - West Central Climate Division | 31 | {1902}-09-12 | 28 | {1918}-09-20 | 10-17 | 11-02 | 11-11 |
| MANCHESTER-2 | 32 | {2014}-09-13 | 27 | {1984}-09-16 | 10-13 | 11-02 | 11-11 |
| Ames Area | 31 | {1902}-09-13 | 26 | {1918}-09-21 | 10-17 | 11-02 | 11-11 |
| Sioux City Area | 30 | {1902}-09-13 | 25 | {1995}-09-22 | 10-17 | 11-02 | 11-10 |
| SIOUX-CITY-WSO-AP | 30 | {1902}-09-13 | 25 | {1995}-09-22 | 10-17 | 11-02 | 11-10 |
| Iowa - Northeast Climate Division | 32 | {1902}-09-13 | 26 | {1926}-09-26 | 10-13 | 11-02 | 11-11 |
| AMES-8-WSW | 31 | {1902}-09-13 | 26 | {1918}-09-21 | 10-18 | 11-02 | 11-12 |
| CLARINDA | 31 | {1902}-09-13 | 28 | {1918}-09-21 | 10-17 | 11-02 | 11-19 |
| CASCADE | 32 | {2023}-08-31 | 28 | {1953,1974}-09-22 | 10-10 | 11-03 | 11-11 |
| OAKLAND-2-E | 32 | {1974}-09-03 | 28 | {1995}-09-22 | 10-17 | 11-03 | 11-11 |
| RED-OAK | 32 | {1940}-09-11 | 28 | {1995}-09-22 | 10-19 | 11-03 | 11-21 |
| WILLIAMSBURG | 32 | {1917}-09-11 | 28 | {1991}-09-20 | 10-17 | 11-03 | 11-12 |
| Iowa Drought Region 4 - Southwest | 32 | {1902}-09-12 | 26 | {1942}-09-28 | 10-19 | 11-03 | 11-13 |
| CORNING | 32 | {1902}-09-12 | 27 | {1983}-09-21 | 10-17 | 11-03 | 11-13 |
| VINTON | 32 | {1902,1953}-09-13 | 28 | {1982}-09-21 | 10-17 | 11-03 | 11-12 |
| Iowa Drought Region 3 - Northeast | 32 | {1902}-09-13 | 27 | {1926}-09-26 | 10-17 | 11-03 | 11-11 |
| Iowa Average | 32 | {1902}-09-13 | 24 | {1942}-09-28 | 10-17 | 11-03 | 11-11 |
| Dubuque Airport | 32 | {2007}-09-15 | 28 | {1956}-09-20 | 10-16 | 11-03 | 11-13 |
| Creston | 31 | {1924}-09-15 | 28 | {1991}-09-19 | 10-18 | 11-03 | 11-13 |
| Iowa - Central Climate Division | 31 | {1929}-09-18 | 28 | {1913}-09-22 | 10-17 | 11-03 | 11-11 |
| AMES 5 SE | 32 | {1902}-09-13 | 28 | {1926}-09-26 | 10-19 | 11-04 | 11-20 |
| CHARITON | 32 | {1955}-09-12 | 28 | {1918,1991}-09-20 | 10-17 | 11-05 | 11-21 |
| MOUNT-AYR | 32 | {1902}-09-13 | 28 | {1991}-09-19 | 10-19 | 11-05 | 11-21 |
| Cedar Rapids Area | 31 | {2007}-09-15 | 28 | {2012}-09-24 | 10-18 | 11-05 | 11-19 |
| Cedar Rapids Airport | 31 | {2007}-09-15 | 28 | {2012}-09-24 | 10-17 | 11-05 | 11-19 |
| BELLEVUE-L-AND-D-12 | 32 | {1986}-08-30 | 28 | {1974,1995}-09-23 | 10-17 | 11-06 | 11-21 |
| Iowa - Southwest Climate Division | 32 | {1902}-09-13 | 26 | {1942}-09-28 | 10-19 | 11-06 | 11-21 |
| Iowa City | 32 | {1923}-09-14 | 28 | {1916}-09-18 | 10-19 | 11-06 | 11-21 |
| CEDAR-RAPIDS-1 | 32 | {2007}-09-15 | 24 | {1926}-09-26 | 10-23 | 11-06 | 11-21 |
| Dubuque Area | 32 | {2007}-09-15 | 28 | {1956}-09-20 | 10-19 | 11-06 | 11-21 |
| NEWTON | 32 | {1929}-09-18 | 23 | {1942}-09-28 | 10-20 | 11-06 | 11-21 |
| Iowa - East Central Climate Division | 32 | {1929}-09-18 | 28 | {1926}-09-26 | 10-19 | 11-06 | 11-21 |
| WINTERSET | 31 | {1955}-09-12 | 26 | {1896}-09-20 | 10-19 | 11-07 | 11-21 |
| OSCEOLA-3-WSW | 31 | {2007}-09-15 | 28 | {1974}-09-22 | 10-19 | 11-07 | 11-21 |
| SHENANDOAH-1-NE | 32 | {1937}-09-16 | 28 | {1918}-09-20 | 10-24 | 11-07 | 11-21 |
| GUTTENBERG-L-AND-D-10 | 32 | {1973}-09-18 | 25 | {1942}-09-28 | 10-24 | 11-07 | 11-21 |
| BEACONSFIELD | 27 | {1991}-09-19 | 27 | {1991}-09-19 | 10-19 | 11-07 | 11-20 |
| IOWA CITY MUNICIPAL AP | 32 | {1991}-09-20 | 26 | {1995}-09-23 | 10-19 | 11-07 | 11-21 |
| RATHBUN DAM | 32 | {1974}-09-22 | 28 | {1985}-10-01 | 10-17 | 11-07 | 11-21 |
| FAIRFIELD | 32 | {1917}-09-11 | 28 | {1918}-09-21 | 10-24 | 11-08 | 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 | 10-19 | 11-08 | 11-21 |
| OSKALOOSA | 31 | {1902}-09-13 | 27 | {1991}-09-20 | 10-19 | 11-08 | 11-21 |
| SIGOURNEY | 32 | {1902}-09-13 | 25 | {1913}-09-21 | 10-19 | 11-08 | 11-22 |
| GREENFIELD | 32 | {1981}-09-17 | 27 | {1913}-09-22 | 10-19 | 11-08 | 11-21 |
| Lamoni | 32 | {1901}-09-18 | 27 | {1942}-09-28 | 10-24 | 11-08 | 11-21 |
| Iowa - South Central Climate Division | 31 | {1991}-09-19 | 25 | {1942}-09-28 | 10-24 | 11-08 | 11-21 |
| Allerton | 31 | {1991}-09-19 | 27 | {1913}-09-22 | 10-19 | 11-08 | 11-21 |
| Iowa Drought Region 5 - Southeast | 31 | {1991}-09-20 | 24 | {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 |
| CLINTON-1 | 31 | {1902}-09-13 | 28 | {1928}-09-25 | 10-20 | 11-09 | 11-22 |
| Ottumwa | 32 | {2007}-09-15 | 23 | {1942}-09-28 | 10-24 | 11-09 | 11-22 |
| Iowa - Southeast Climate Division | 32 | {1896,1991}-09-20 | 25 | {1942}-09-28 | 10-25 | 11-09 | 11-22 |
| KEOSAUQUA | 31 | {1917}-09-11 | 28 | {1916}-09-18 | 10-24 | 11-10 | 11-22 |
| MOUNT-PLEASANT | 32 | {1902}-09-13 | 28 | {1942}-09-24 | 10-25 | 11-10 | 11-22 |
| CENTERVILLE | 31 | {1913}-09-13 | 28 | {1913}-09-22 | 10-25 | 11-10 | 11-22 |
| Burlington Airport | 30 | {1918}-09-18 | 25 | {1942}-09-28 | 10-27 | 11-10 | 11-24 |
| MUSCATINE | 29 | {1991}-09-20 | 23 | {1942}-09-28 | 10-24 | 11-10 | 11-21 |
| Donnellson | 31 | {1991}-09-20 | 25 | {1942}-09-28 | 10-19 | 11-10 | 11-22 |
| DUBUQUE-LOCK-AND-DAM | 31 | {1956}-09-20 | 24 | {1899}-09-30 | 10-25 | 11-10 | 11-22 |
| DES MOINES WSFO-JOHNSTON | 31 | {1999}-09-21 | 28 | {2004}-10-02 | 10-24 | 11-10 | 11-12 |
| LAMONI | -1 | {2011,2012}-08-07 | -1 | {2011,2012}-08-07 | 10-26 | 11-11 | 11-21 |
| 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 |
| MUSCATINE 2N | 27 | {2003}-10-02 | 27 | {2003}-10-02 | 10-17 | 11-11 | 11-22 |
| KEOKUK LOCK DAM 19 | 30 | {1992}-09-23 | 23 | {1952}-10-06 | 11-02 | 11-13 | 11-28 |