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:
Iowa Average 32 1902-09-13 24 1942-09-28 10-18 11-03 11-12
ALBIA 31 1916-09-18 27 1913-09-22 10-24 11-08 11-21
ALGONA 29 1893-09-02 27 1929-09-18 10-17 11-02 11-10
Allerton 31 1991-09-19 28 2003-09-27 10-18 11-05 11-21
ALLISON 32 1915-08-30 28 1926-09-25 10-17 11-02 11-11
AMES-8-WSW 31 1902-09-13 26 1918-09-21 10-18 11-03 11-12
ANAMOSA-1-WNW 29 1998-09-08 27 1956-09-20 10-10 11-03 11-11
ANKENY-3-S 32 1999-09-18 22 1999-09-21 10-18 11-04 11-19
ATLANTIC-1-NE 30 1893-09-02 28 1902-09-12 10-17 11-01 11-10
AUDUBON 30 1902-09-12 27 1896-09-19 10-17 11-01 11-10
BEDFORD-1-NNW 28 1902-09-13 28 1902-09-13 10-19 11-07 11-21
BELLE-PLAINE 31 1917-09-11 28 1916-09-18 10-17 11-03 11-12
BELLEVUE-L-AND-D-12 32 1986-08-30 28 1974-09-23 10-17 11-05 11-21
BLOOMFIELD 31 1991-09-20 23 1942-09-27 10-24 11-08 11-21
Boone 32 1975-09-12 27 1929-09-18 10-17 11-02 11-12
BRITT 30 1950-08-20 27 1902-09-13 10-12 10-28 11-09
Burlington 30 1918-09-18 25 1942-09-28 10-27 11-10 11-24
CARROLL-2-SSW 28 1974-09-03 28 1974-09-03 10-16 11-01 11-10
CASCADE 32 1955-09-11 28 1953-09-22 10-10 11-03 11-11
CASTANA-EXP-FARM 30 1991-09-19 28 1995-09-22 10-18 11-03 11-12
CEDAR-RAPIDS-1 32 2007-09-15 24 1926-09-26 10-22 11-06 11-21
CENTERVILLE 31 1913-09-13 28 1913-09-22 10-25 11-09 11-22
CHARITON 32 1955-09-12 28 1918-09-20 10-18 11-05 11-21
CHARLES-CITY 32 1955-09-12 28 1991-09-20 10-10 11-03 11-10
CHEROKEE 31 1974-09-03 27 1955-09-11 10-07 10-28 11-07
CLARINDA 31 1902-09-13 28 1918-09-21 10-19 11-03 11-19
CLARION 32 1950-08-20 1 2018-08-28 10-09 11-02 11-09
CLINTON-1 31 1902-09-13 28 1928-09-25 10-20 11-09 11-22
CORNING 32 1902-09-12 27 1983-09-21 10-18 11-03 11-13
CRESCO-1-NE 31 1975-09-13 27 1991-09-20 10-09 10-28 11-09
Creston 31 1924-09-15 28 1991-09-19 10-19 11-03 11-20
DECORAH-2-N 32 1915-08-30 28 1946-09-02 10-10 11-01 11-10
DENISON 29 1902-09-12 21 1918-09-21 10-18 11-02 11-11
Des Moines Airport 31 1995-09-22 26 1942-09-28 10-24 11-08 11-21
Donnellson 31 1991-09-20 25 1942-09-28 10-25 11-10 11-22
DUBUQUE-LOCK-AND-DAM 31 1956-09-20 24 1899-09-30 10-25 11-10 11-22
Eldora 32 1962-09-20 28 1974-09-22 10-11 11-03 11-10
Elkader 6SSW (Osborn) 32 1893-08-29 0 2002-09-02 10-09 10-28 11-10
Emmetsburg 32 2011-09-15 24 1995-09-22 10-10 11-01 11-10
ESTHERVILLE-2-N 32 1924-09-09 27 1929-09-18 10-07 10-27 11-06
FAIRFIELD 32 1917-09-11 28 1918-09-21 10-24 11-08 11-22
FAYETTE 32 1949-09-01 27 1902-09-12 10-10 10-28 11-10
FOREST-CITY 31 1949-09-01 27 1929-09-18 10-10 10-28 11-09
FORT-DODGE 32 1974-09-03 27 1902-09-13 10-17 11-02 11-10
Fort Madison 32 1983-09-23 27 1974-10-02 10-28 11-10 11-28
GLENWOOD 30 1902-09-12 28 1902-09-13 10-19 11-03 11-19
GREENFIELD 32 1981-09-17 27 1913-09-22 10-23 11-06 11-21
GRINNELL-3-SW 31 1976-09-10 27 1991-09-20 10-17 11-02 11-11
GRUNDY-CENTER 32 1902-09-12 28 1929-09-18 10-13 11-02 11-10
GUTHRIE-CENTER 31 1893-09-02 28 1991-09-19 10-17 11-02 11-11
GUTTENBERG-L-AND-D-10 32 1973-09-18 25 1942-09-28 10-24 11-06 11-21
HAMPTON-2-NW 32 1955-09-11 28 1955-09-12 10-12 11-01 11-10
HARLAN 29 1902-09-12 27 1902-09-13 10-17 11-02 11-11
HAWARDEN 31 1974-09-03 24 1991-09-19 10-08 10-28 11-04
Holstein 31 1991-09-20 28 1984-09-29 10-18 11-05 11-20
HUMBOLDT-2 31 1902-09-13 28 1934-09-16 10-16 11-02 11-10
INDEPENDENCE-2-W 32 1974-09-03 28 1975-09-13 10-10 10-29 11-10
INDIANOLA-2-SSW 30 1979-09-15 28 1979-09-22 10-19 11-08 11-21
Iowa City 32 1923-09-14 28 1916-09-18 10-20 11-06 11-21
IOWA-FALLS 31 1915-08-30 28 1894-09-18 10-12 11-02 11-10
JEFFERSON 32 1893-08-29 28 1929-09-18 10-18 11-02 11-11
KEOSAUQUA 31 1917-09-11 28 1916-09-18 10-24 11-09 11-22
KNOXVILLE 31 1916-09-18 28 1926-09-26 10-24 11-08 11-21
Lamoni 32 1901-09-18 27 1942-09-28 10-24 11-08 11-21
Le Claire L&D 14 32 1942-09-26 28 1942-09-28 10-28 11-11 11-24
LEMARS 31 1955-09-11 28 1902-09-12 10-12 10-29 11-08
LOGAN 30 1902-09-12 28 1902-09-13 10-18 11-02 11-11
MANCHESTER-2 32 2014-09-13 27 1984-09-16 10-07 10-28 11-10
MAQUOKETA-2-W 31 1917-09-11 28 1983-09-23 10-17 11-03 11-12
MARSHALLTOWN 31 1955-09-12 28 1896-09-20 10-13 11-02 11-11
MASON-CITY 30 1915-08-30 28 1923-09-14 10-10 11-01 11-08
Milford 32 1974-09-03 27 1983-09-21 10-09 10-31 11-08
MOUNT-AYR 32 1902-09-13 28 1991-09-19 10-19 11-05 11-21
MOUNT-PLEASANT 32 1902-09-13 28 1942-09-24 10-25 11-09 11-22
MUSCATINE 29 1991-09-20 23 1942-09-28 10-24 11-10 11-21
NEW-HAMPTON 28 1949-09-01 28 1949-09-01 10-13 11-02 11-10
NEWTON 29 1974-09-22 27 1972-09-30 10-18 11-05 11-20
NORTHWOOD 32 1953-09-13 28 1929-09-18 10-10 10-28 11-08
OAKLAND-2-E 32 1974-09-03 28 1995-09-22 10-17 11-03 11-11
OELWEIN-2-S 28 1955-09-11 28 1955-09-11 10-17 11-02 11-10
ONAWA 30 1955-09-11 28 1991-09-19 10-19 11-02 11-11
OSAGE 30 1949-09-14 28 1929-09-18 10-13 11-02 11-10
OSCEOLA-3-WSW 31 2007-09-15 28 1974-09-22 10-19 11-05 11-20
OSKALOOSA 31 1902-09-13 27 1991-09-20 10-19 11-06 11-21
Ottumwa 32 2007-09-15 23 1942-09-28 10-24 11-08 11-22
PERRY 32 1955-09-12 27 1929-09-18 10-17 11-02 11-11
POCAHONTAS 31 1946-09-02 27 1929-09-18 10-10 10-28 11-09
PRIMGHAR 32 1949-09-13 27 1991-09-19 10-16 11-02 11-10
RED-OAK 32 1940-09-11 28 1995-09-22 10-19 11-03 11-21
ROCK-RAPIDS 31 1974-09-03 26 1894-09-10 10-07 10-24 11-05
ROCKWELL-CITY 32 1902-09-12 28 1929-09-18 10-17 11-01 11-10
SAC-CITY 32 1974-09-03 28 1918-09-20 10-17 11-02 11-11
Sheldon 32 1974-09-03 28 1902-09-12 10-09 10-27 11-04
SHENANDOAH-1-NE 32 1937-09-16 28 1918-09-20 10-19 11-07 11-21
SIBLEY-5-NNE 30 1950-08-20 23 1955-09-11 10-07 10-26 11-03
SIDNEY 30 1991-09-18 28 1995-09-22 10-25 11-08 11-21
SIGOURNEY 32 1902-09-13 25 1913-09-21 10-19 11-08 11-21
SIOUX-CITY-WSO-AP 30 1902-09-13 25 1995-09-22 10-17 11-02 11-10
SIOUX-RAPIDS 31 1974-09-03 28 1991-09-19 10-09 10-27 11-07
Spencer 31 1974-09-03 28 2007-09-15 10-09 10-27 11-08
STORM-LAKE-2-E 32 1902-09-12 28 1929-09-18 10-17 11-02 11-10
TIPTON 32 1902-09-13 28 1991-09-20 10-18 11-05 11-21
TOLEDO 31 1917-09-11 27 1896-09-20 10-17 11-03 11-11
TRIPOLI-4-N 31 2007-09-15 27 1974-09-22 10-15 11-03 11-10
VINTON 32 1953-09-13 28 1982-09-21 10-17 11-05 11-20
Wapello 31 1991-09-20 24 1942-09-28 10-25 11-09 11-22
WASHINGTON 30 1902-09-13 28 1983-09-23 10-24 11-08 11-21
WATERLOO 32 1917-09-11 28 1929-09-18 10-13 11-02 11-10
WAUKON 32 1937-09-16 25 1942-09-25 10-13 11-02 11-10
WEBSTER-CITY 30 1955-09-11 25 1929-09-18 10-12 11-01 11-10
WILLIAMSBURG 32 1917-09-11 28 1991-09-20 10-18 11-04 11-21
WINTERSET 31 1955-09-12 26 1896-09-20 10-19 11-07 11-21
Iowa - Northwest Climate Division 32 1974-09-03 28 1991-09-19 10-12 10-28 11-08
Iowa - North Central Climate Division 32 2007-09-15 28 1929-09-18 10-13 11-02 11-10
Iowa - Northeast Climate Division 32 1902-09-13 28 1974-09-22 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
Iowa - Central Climate Division 32 1902-09-13 28 1913-09-22 10-18 11-03 11-12
Iowa - East Central Climate Division 32 1929-09-18 28 1926-09-26 10-19 11-05 11-21
Iowa - Southwest Climate Division 30 1901-09-18 26 1942-09-28 10-19 11-06 11-21
Iowa - South Central Climate Division 31 1991-09-19 25 1942-09-28 10-24 11-08 11-21
Iowa - Southeast Climate Division 32 1902-09-13 25 1942-09-28 10-24 11-08 11-22
Waterloo Area 32 1917-09-11 28 1929-09-18 10-13 11-02 11-11
Cedar Rapids Area 31 2007-09-15 28 2012-09-24 10-19 11-03 11-19
Dubuque Area 32 2007-09-15 28 1956-09-20 10-20 11-05 11-21
Des Moines Area 31 1995-09-22 26 1942-09-28 10-24 11-08 11-21
Spencer Area 31 1974-09-03 28 2007-09-15 10-09 10-27 11-08
Sioux City Area 30 1902-09-13 25 1995-09-22 10-17 11-02 11-10