42.898°N, 106.474°W · station CPRthr · 88 years of record
54°F
COLDEST SEP 8 SINCE 2025
forecast low · Sep 8
7-Day Forecast
NWS NDFD forecast low temperature for Casper.
This Day in History
Every year's low on each of the next 7 forecast dates at Casper — toggle a day below. The forecast line shows where it lands; the ringed bar is the coldest on record.
Ranks
#81 / 86
coldest Sep 2 in 86 yrs of record
Coldest Sep 2 ever
33°F
set in 2006
Mildest Sep 2 ever
66°F
set in 2015
Forecast low 58°F — 81st coldest Sep 2 of 86 years · record 33°F (2006) · coldest since 2025.
Ranks
#77 / 86
coldest Sep 3 in 86 yrs of record
Coldest Sep 3 ever
31°F
set in 2010
Mildest Sep 3 ever
65°F
set in 1945
Forecast low 58°F — 77th coldest Sep 3 of 86 years · record 31°F (2010) · coldest since 2025.
Ranks
#70 / 86
coldest Sep 4 in 86 yrs of record
Coldest Sep 4 ever
32°F
set in 2008
Mildest Sep 4 ever
65°F
set in 1945
Forecast low 55°F — 70th coldest Sep 4 of 86 years · record 32°F (2008) · coldest since 2025.
Ranks
#77 / 86
coldest Sep 5 in 86 yrs of record
Coldest Sep 5 ever
34°F
set in 1965
Mildest Sep 5 ever
66°F
set in 1960
Forecast low 57°F — 77th coldest Sep 5 of 86 years · record 34°F (1965) · coldest since 2025.
Ranks
#78 / 86
coldest Sep 6 in 86 yrs of record
Coldest Sep 6 ever
32°F
set in 2025
Mildest Sep 6 ever
65°F
set in 2013
Forecast low 56°F — 78th coldest Sep 6 of 86 years · record 32°F (2025) · coldest since 2025.
Ranks
#74 / 86
coldest Sep 7 in 86 yrs of record
Coldest Sep 7 ever
28°F
set in 2010
Mildest Sep 7 ever
58°F
set in 1960
Forecast low 55°F — 74th coldest Sep 7 of 86 years · record 28°F (2010) · coldest since 2025.
Ranks
#73 / 86
coldest Sep 8 in 86 yrs of record
Coldest Sep 8 ever
29°F
set in 1962
Mildest Sep 8 ever
62°F
set in 1952
Forecast low 54°F — 73rd coldest Sep 8 of 86 years · record 29°F (1962) · coldest since 2025.
The hottest and coldest ever recorded at Casper in each calendar month, and for the whole 1939–2026 record — with the year each was set.
Month
Record High
Record Low
Jan
60°FJan 30, 1971
-40°FJan 24, 1949
Feb
68°FFeb 21, 1982
-32°FFeb 17, 2006
Mar
83°FMar 21, 2026
-25°FMar 10, 2022
Apr
84°FApr 30, 1992
-6°FApr 12, 1997
May
95°FMay 29, 2003
16°FMay 12, 1953
Jun
102°FJun 24, 1988
25°FJun 10, 2019
Jul
104°FJul 12, 1954
30°FJul 4, 1972
Aug
103°FAug 2, 2026
29°FAug 23, 2015
Sep
100°FSep 4, 2022
15°FSep 28, 1945
Oct
87°FOct 1, 1992
-9°FOct 29, 2019
Nov
73°FNov 4, 2020
-27°FNov 12, 2014
Dec
66°FDec 2, 2021
-42°FDec 22, 2022
All-time
104°FJul 12, 1954
-42°FDec 22, 2022
2026 Records So Far
Records set or tied at Casper so far this year — through Aug 30.
Record Highs in 2026
21 broke
plus 4 tied — daily record highs set this year
Monthly high records this year: Mar (83°F), Aug (103°F)
Record Lows in 2026
3 broke
plus 0 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
74°F
record high minimum — the night it never cooled · Jul 18, 2006
Coldest high ever
-25°F
record low maximum — the day it never warmed · Feb 3, 1989
Month
Warmest low
Coldest high
Jan
43°FJan 1, 1997
-19°FJan 11, 1963
Feb
42°FFeb 10, 1951
-25°FFeb 3, 1989
Mar
49°FMar 15, 2015
3°FMar 5, 1943
Apr
53°FApr 14, 1942
13°FApr 9, 2013
May
58°FMay 26, 1942
29°FMay 1, 1954
Jun
68°FJun 25, 1988
37°FJun 1, 1951
Jul
74°FJul 18, 2006
54°FJul 11, 1951
Aug
71°FAug 1, 1955
52°FAug 17, 1960
Sep
66°FSep 4, 1960
27°FSep 17, 1965
Oct
58°FOct 8, 1954
8°FOct 29, 2019
Nov
48°FNov 15, 1941
-3°FNov 15, 1955
Dec
48°FDec 3, 1941
-20°FDec 20, 1990
All-time
74°FJul 18, 2006
-25°FFeb 3, 1989
Cold Streaks
Current run
0 days
consecutive days with a low ≤ 32°F
Longest ever
147 days
record run, ended Apr 13 2008
So far in 2026
97 days
days with a low ≤ 32°F this year
Climate Normals
Normal low & low by month, from Casper's own 1991–2020 record. Today's normal low: 46°F · forecast is +8° vs normal.