43.578°N, 96.754°W · station FSDthr · 134 years of record
93°F
HOTTEST SEP 5 SINCE 2003
forecast high · Sep 5
7-Day Forecast
NWS NDFD forecast high temperature for Sioux Falls.
This Day in History
Every year's high on each of the next 7 forecast dates at Sioux Falls — toggle a day below. The forecast line shows where it lands; the ringed bar is the hottest on record.
Ranks
#37 / 133
warmest Sep 1 in 133 yrs of record
Warmest Sep 1 ever
97°F
set in 1898
Coolest Sep 1 ever
57°F
set in 1974
Forecast high 86°F — 37th warmest Sep 1 of 133 years · record 97°F (1898) · warmest since 2024.
Ranks
#21 / 133
warmest Sep 2 in 133 yrs of record
Warmest Sep 2 ever
101°F
set in 2023
Coolest Sep 2 ever
56°F
set in 1909
Forecast high 89°F — 21st warmest Sep 2 of 133 years · record 101°F (2023) · warmest since 2023.
Ranks
#12 / 133
warmest Sep 3 in 133 yrs of record
Warmest Sep 3 ever
99°F
set in 1956
Coolest Sep 3 ever
60°F
set in 1919
Forecast high 92°F — 12th warmest Sep 3 of 133 years · record 99°F (1956) · warmest since 2023.
Ranks
#7 / 133
warmest Sep 4 in 133 yrs of record
Warmest Sep 4 ever
104°F
set in 1913
Coolest Sep 4 ever
62°F
set in 1928
Forecast high 92°F — 7th warmest Sep 4 of 133 years · record 104°F (1913) · warmest since 2023.
Ranks
#10 / 133
warmest Sep 5 in 133 yrs of record
Warmest Sep 5 ever
104°F
set in 1913
Coolest Sep 5 ever
54°F
set in 1965
Forecast high 93°F — 10th warmest Sep 5 of 133 years · record 104°F (1913) · warmest since 2003.
Ranks
#29 / 133
warmest Sep 6 in 133 yrs of record
Warmest Sep 6 ever
104°F
set in 1913
Coolest Sep 6 ever
55°F
set in 1956
Forecast high 88°F — 29th warmest Sep 6 of 133 years · record 104°F (1913) · warmest since 2021.
Ranks
#34 / 133
warmest Sep 7 in 133 yrs of record
Warmest Sep 7 ever
104°F
set in 1976
Coolest Sep 7 ever
55°F
set in 1911
Forecast high 85°F — 34th warmest Sep 7 of 133 years · record 104°F (1976) · warmest since 2022.
The hottest and coldest ever recorded at Sioux Falls in each calendar month, and for the whole 1893–2026 record — with the year each was set.
Month
Record High
Record Low
Jan
66°FJan 24, 1981
-38°FJan 12, 1912
Feb
70°FFeb 23, 1958
-42°FFeb 9, 1899
Mar
89°FMar 21, 2026
-23°FMar 11, 1948
Apr
98°FApr 28, 1910
4°FApr 3, 1936
May
104°FMay 30, 1934
17°FMay 4, 1967
Jun
110°FJun 21, 1988
32°FJun 7, 1897
Jul
110°FJul 17, 1936
34°FJul 9, 1895
Aug
109°FAug 24, 1936
34°FAug 29, 1893
Sep
104°FSep 4, 1913
13°FSep 29, 1899
Oct
95°FOct 1, 2023
-5°FOct 29, 1925
Nov
82°FNov 6, 2020
-17°FNov 14, 1959
Dec
63°FDec 1, 1998
-31°FDec 29, 1917
All-time
110°FJul 17, 1936
-42°FFeb 9, 1899
2026 Records So Far
Records set or tied at Sioux Falls so far this year — through Aug 30.
Record Highs in 2026
4 broke
plus 2 tied — daily record highs set this year
Monthly high record this year: Mar (89°F)
Record Lows in 2026
0 broke
plus 1 tied — daily record lows set this year
Record Warm Nights & Cold Days
Two more daily records, kept separate from the rankings: the warmest a night has ever stayed (record high minimum) and the coldest a day has ever gotten (record low maximum) — the flip side of the usual record high and low.
Warmest low ever
81°F
record high minimum — the night it never cooled · Jul 12, 1936
Coldest high ever
-23°F
record low maximum — the day it never warmed · Feb 8, 1899
Month
Warmest low
Coldest high
Jan
43°FJan 25, 1944
-18°FJan 24, 1897
Feb
44°FFeb 23, 2000
-23°FFeb 8, 1899
Mar
63°FMar 18, 2012
-4°FMar 1, 1919
Apr
65°FApr 24, 1924
22°FApr 1, 1975
May
77°FMay 31, 1934
36°FMay 5, 1944
Jun
78°FJun 21, 1988
46°FJun 1, 1946
Jul
81°FJul 12, 1936
58°FJul 18, 1912
Aug
81°FAug 14, 1938
57°FAug 25, 1987
Sep
77°FSep 14, 1939
41°FSep 28, 1985
Oct
73°FOct 1, 2023
19°FOct 29, 1925
Nov
59°FNov 8, 2020
-2°FNov 29, 1896
Dec
44°FDec 1, 1962
-16°FDec 21, 1989
All-time
81°FJul 12, 1936
-23°FFeb 8, 1899
Hot Streaks
Current run
2 days
consecutive days with a high ≥ 90°F
Longest ever
19 days
record run, ended Jul 5 1910
So far in 2026
21 days
days with a high ≥ 90°F this year
Climate Normals
Normal high & low by month, from Sioux Falls's own 1991–2020 record. Today's normal high: 79°F · forecast is +14° vs normal.
Sioux Falls's observed daily high for the last six weeks — a white ring marks any day that broke or tied its daily record for that date.
2026 So Far
Every day this year against Sioux Falls's own record — the record high, the normal, and the full span ever seen. A shareable look at where the year stands.