Iowa Environmental Mesonet

Iowa State University Department of Agronomy

View current Iowa Road Conditions

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:
SIBLEY-5-NNE 30 1974-09-03 23 1955-09-11 10-04 10-26 11-03
ROCK-RAPIDS 31 1974-09-03 26 1894-09-10 10-06 10-24 11-03
CHEROKEE 31 1974-09-03 27 1955-09-11 10-07 10-26 11-04
HAWARDEN 31 1974-09-03 24 1991-09-19 10-09 10-28 11-04
Sheldon 32 1974-09-03 28 2007-09-15 10-09 10-28 11-04
Boone 32 1975-09-12 28 1981-09-18 10-10 11-01 11-04
POCAHONTAS 30 2007-09-15 28 1983-09-20 10-07 10-28 11-05
ESTHERVILLE-2-N 30 2007-09-15 28 1991-09-20 10-07 10-28 11-05
CRESCO-1-NE 31 1975-09-13 27 1991-09-20 10-07 10-29 11-05
NORTHWOOD 31 1953-09-13 26 1974-09-22 10-09 11-02 11-05
SIOUX-RAPIDS 31 1974-09-03 28 1991-09-19 10-09 10-29 11-06
IOWA-FALLS 32 1976-09-10 26 1974-09-22 10-10 11-02 11-07
GRUNDY-CENTER 31 2007-09-15 27 1974-09-22 10-07 10-29 11-07
HUMBOLDT-2 32 1976-09-17 26 1974-09-22 10-09 11-02 11-07
CLARION 32 1974-09-03 25 1974-09-22 10-09 10-28 11-07
FOREST-CITY 31 2007-09-15 26 1974-09-22 10-09 11-02 11-08
EMMETSBURG 31 1991-09-19 24 1995-09-22 10-10 11-02 11-08
PRIMGHAR 31 1984-09-15 27 1991-09-19 10-09 11-02 11-08
STORM-LAKE-2-E 32 1902-09-12 28 1929-09-18 10-17 11-02 11-08
BRITT 31 2007-09-15 25 1983-09-22 10-09 11-02 11-08
SIOUX-CITY-WSO-AP 32 2007-09-15 25 1995-09-22 10-15 11-02 11-08
MASON-CITY 30 1915-08-30 28 1923-09-14 10-10 11-01 11-08
CARROLL-2-SSW 28 1974-09-03 28 1974-09-03 10-07 10-29 11-08
LEMARS 25 1893-09-02 25 1893-09-02 10-17 10-29 11-08
WAUKON 32 1956-09-20 27 1984-09-26 10-10 11-02 11-09
MANCHESTER-2 29 2007-09-15 27 1984-09-16 10-07 10-28 11-09
OSAGE 32 2007-09-15 28 1974-09-22 10-17 11-03 11-10
WINTERSET 31 1955-09-12 28 1962-09-20 10-18 11-04 11-10
CHARLES-CITY 32 1955-09-12 28 1991-09-20 10-10 11-03 11-10
HARLAN 29 1991-09-19 27 1951-09-28 10-17 11-03 11-10
PERRY 32 1955-09-12 28 1974-09-22 10-09 11-03 11-10
TOLEDO 31 2007-09-15 28 1962-09-20 10-10 11-03 11-10
DECORAH-2-N 32 1915-08-30 28 1946-09-02 10-10 11-02 11-10
AUDUBON 30 1955-09-12 28 1991-09-20 10-10 11-02 11-10
ROCKWELL-CITY 32 1902-09-12 28 1929-09-18 10-17 11-02 11-10
NEW-HAMPTON 28 1949-09-01 28 1949-09-01 10-17 11-02 11-10
HAMPTON-2-NW 32 1955-09-11 28 1955-09-12 10-17 11-02 11-10
WEBSTER-CITY 30 1955-09-11 25 1929-09-18 10-13 11-02 11-10
TRIPOLI-4-N 31 2007-09-15 27 1974-09-22 10-10 11-03 11-10
INDEPENDENCE-2-W 32 1974-09-03 28 1975-09-13 10-10 11-03 11-10
WATERLOO 32 1917-09-11 28 1929-09-18 10-13 11-02 11-10
Eldora 32 1962-09-20 28 1974-09-22 10-10 11-03 11-10
FAYETTE 32 1949-09-01 27 1902-09-12 10-10 10-28 11-10
ALGONA 29 1893-09-02 27 1929-09-18 10-17 11-02 11-10
ATLANTIC-1-NE 30 1893-09-02 28 1902-09-12 10-17 11-02 11-10
FORT-DODGE 32 1974-09-03 28 1995-09-22 10-09 11-02 11-10
OAKLAND-2-E 32 1974-09-03 28 1995-09-22 10-10 11-03 11-10
CASCADE 32 1955-09-11 28 1953-09-22 10-07 11-03 11-10
OELWEIN-2-S 28 1955-09-11 28 1955-09-11 10-10 11-02 11-10
ONAWA 30 1955-09-11 28 1991-09-19 10-19 11-02 11-11
GUTHRIE-CENTER 31 1893-09-02 28 1991-09-19 10-17 11-02 11-11
SAC-CITY 32 1974-09-03 27 1974-09-22 10-10 11-02 11-11
MARSHALLTOWN 31 1955-09-12 28 1896-09-20 10-17 11-02 11-11
AMES-8-WSW 31 1902-09-13 26 1918-09-21 10-18 11-02 11-12
LOGAN 30 1902-09-12 28 1902-09-13 10-18 11-02 11-12
DENISON 29 1902-09-12 21 1918-09-21 10-18 11-02 11-12
GRINNELL-3-SW 31 1976-09-10 27 1991-09-20 10-17 11-03 11-12
ANAMOSA-1-WNW 29 1955-09-12 27 1956-09-20 10-10 11-03 11-12
MAQUOKETA-2-W 31 1917-09-11 28 1983-09-23 10-17 11-04 11-13
ALLISON 30 1991-09-20 28 1984-09-26 10-18 11-03 11-16
CASTANA-EXP-FARM 30 1991-09-19 28 1995-09-22 10-18 11-03 11-19
JEFFERSON 32 2007-09-16 23 1974-10-02 10-18 11-04 11-19
CLARINDA 31 1902-09-13 28 1918-09-21 10-19 11-03 11-19
BELLE-PLAINE 32 1955-09-12 28 1991-09-20 10-18 11-04 11-19
CORNING 32 1902-09-12 27 1983-09-21 10-18 11-03 11-19
Iowa Average 31 1902-09-13 27 1926-09-26 10-19 11-03 11-19
Creston 28 1991-09-19 28 1991-09-19 10-18 11-03 11-20
SHENANDOAH-1-NE 30 1980-09-17 26 1983-09-23 10-19 11-05 11-20
BEDFORD-1-NNW 27 1991-09-19 27 1991-09-19 10-19 11-04 11-20
OSCEOLA-3-WSW 31 2007-09-15 28 1974-09-22 10-18 11-04 11-20
ANKENY-3-S 32 1991-09-20 28 1984-09-26 10-18 11-04 11-20
CHARITON 32 1955-09-12 28 1991-09-20 10-18 11-04 11-20
GREENFIELD 32 1981-09-17 28 1995-09-22 10-19 11-04 11-20
Des Moines Airport 31 1995-09-22 28 1984-09-29 10-19 11-05 11-20
WILLIAMSBURG 31 1955-09-12 28 1991-09-20 10-18 11-04 11-20
VINTON 32 1953-09-13 28 1982-09-21 10-10 11-03 11-20
RED-OAK 32 1993-09-15 28 1995-09-22 10-18 11-04 11-20
Lamoni 32 1991-09-19 24 1974-10-02 10-19 11-05 11-21
ALBIA 31 1991-09-19 25 1984-09-29 10-25 11-06 11-21
TIPTON 32 1902-09-13 28 1991-09-20 10-19 11-05 11-21
OSKALOOSA 31 1902-09-13 27 1991-09-20 10-19 11-05 11-21
GLENWOOD 27 1901-09-18 27 1901-09-18 10-19 11-04 11-21
IOWA-CITY 32 1956-09-20 24 1958-10-01 10-19 11-06 11-21
BELLEVUE-L-AND-D-12 31 1991-09-20 25 1995-09-23 10-18 11-04 11-21
KNOXVILLE 31 1991-09-19 27 1974-10-02 10-19 11-07 11-21
BLOOMFIELD 31 1991-09-20 25 1974-10-02 10-19 11-05 11-21
NEWTON 29 1974-09-22 27 1972-09-30 10-18 11-05 11-21
GUTTENBERG-L-AND-D-10 32 1973-09-18 28 1984-09-29 10-19 11-05 11-21
SIGOURNEY 31 1995-09-22 28 1964-09-28 10-19 11-05 11-21
CEDAR-RAPIDS-1 32 2007-09-15 24 1926-09-26 10-19 11-05 11-21
MOUNT-AYR 32 1902-09-13 28 1991-09-19 10-23 11-05 11-21
INDIANOLA-2-SSW 30 1979-09-15 28 1979-09-22 10-19 11-08 11-21
MOUNT-PLEASANT 29 1991-09-20 25 1974-10-02 10-19 11-10 11-21
FAIRFIELD 32 1917-09-11 28 1918-09-21 10-24 11-08 11-22
WASHINGTON 30 1902-09-13 28 1983-09-23 10-24 11-08 11-22
DUBUQUE-LOCK-AND-DAM 31 1956-09-20 24 1899-09-30 10-25 11-10 11-22
CLINTON-1 22 1924-08-31 22 1924-08-31 10-19 11-06 11-22
KEOSAUQUA 31 1917-09-11 28 1916-09-18 10-24 11-09 11-22
CENTERVILLE 32 1991-09-19 27 1979-10-05 10-19 11-05 11-23
Le Claire L&D 14 32 1984-09-29 25 1974-10-02 10-28 11-11 11-24
FORT-MADISON 32 1983-09-23 27 1974-10-02 10-28 11-10 11-24
Ottumwa 29 1981-08-03 27 1984-09-29 10-24 11-08 11-24
SIDNEY 30 1991-09-19 28 1995-09-22 10-27 11-05 11-24
Burlington 32 1991-09-20 26 2003-10-02 10-27 11-10 11-24
MUSCATINE 29 1991-09-20 26 1984-09-29 10-19 11-10 11-24