COLDESTSINCE.COMBrowse statesThe AlmanacYear in ReviewThe Wire
COLD94
Coldest Since
National Cold Records
Wyoming · THREADEX · 1939–2026

Casper, WY

42.898°N, 106.474°W · station CPRthr · 88 years of record
54°F
forecast low · Sep 8

7-Day Forecast

NWS NDFD forecast low temperature for Casper.
58°WED9/258°THU9/355°FRI9/457°SAT9/556°SUN9/655°MON9/754°TUE9/8

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

#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.
1940: 60°F1941: 34°F1942: 49°F1943: 38°F1944: 48°F1945: 40°F1946: 45°F1947: 52°F1948: 42°F1949: 49°F1950: 50°F1951: 49°F1952: 62°F1953: 56°F1954: 53°F1955: 52°F1956: 40°F1957: 47°F1958: 55°F1959: 51°F1960: 47°F1961: 45°F1962: 29°F1963: 56°F1964: 42°F1965: 48°F1966: 53°F1967: 50°F1968: 43°F1969: 47°F1970: 48°F1971: 45°F1972: 45°F1973: 53°F1974: 46°F1975: 42°F1976: 44°F1977: 40°F1978: 56°F1979: 46°F1980: 60°F1981: 40°F1982: 56°F1983: 56°F1984: 39°F1985: 43°F1986: 43°F1987: 41°F1988: 51°F1989: 43°F1990: 54°F1991: 55°F1992: 41°F1993: 47°F1994: 46°F1995: 45°F1996: 36°F1997: 48°F1998: 58°F1999: 32°F2000: 36°F2001: 36°F2002: 52°F2003: 49°F2004: 39°F2005: 49°F2006: 39°F2007: 47°F2008: 39°F2009: 48°F2010: 61°F2011: 41°F2012: 45°F2013: 56°F2014: 50°F2015: 34°F2016: 45°F2017: 44°F2018: 42°F2019: 41°F2020: 31°F2021: 41°F2022: 53°F2023: 43°F2024: 47°F2025: 50°F54° forecast253035404550556065194019501960197019801990200020102020
📖 Casper's full Climate Almanac →

The Numbers

Forecast low · Sep 854°F
Coldest this date since2025
This-date record29°F
This-date rank#73 of 86
Coldest at any time since2026
All-time record-42°F (2022)
Odds to tie/break0.0% (daily)
Period of record1939–2026

Record Book

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.
MonthRecord HighRecord Low
Jan60°FJan 30, 1971-40°FJan 24, 1949
Feb68°FFeb 21, 1982-32°FFeb 17, 2006
Mar83°FMar 21, 2026-25°FMar 10, 2022
Apr84°FApr 30, 1992-6°FApr 12, 1997
May95°FMay 29, 200316°FMay 12, 1953
Jun102°FJun 24, 198825°FJun 10, 2019
Jul104°FJul 12, 195430°FJul 4, 1972
Aug103°FAug 2, 202629°FAug 23, 2015
Sep100°FSep 4, 202215°FSep 28, 1945
Oct87°FOct 1, 1992-9°FOct 29, 2019
Nov73°FNov 4, 2020-27°FNov 12, 2014
Dec66°FDec 2, 2021-42°FDec 22, 2022
All-time104°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
MonthWarmest lowColdest high
Jan43°FJan 1, 1997-19°FJan 11, 1963
Feb42°FFeb 10, 1951-25°FFeb 3, 1989
Mar49°FMar 15, 20153°FMar 5, 1943
Apr53°FApr 14, 194213°FApr 9, 2013
May58°FMay 26, 194229°FMay 1, 1954
Jun68°FJun 25, 198837°FJun 1, 1951
Jul74°FJul 18, 200654°FJul 11, 1951
Aug71°FAug 1, 195552°FAug 17, 1960
Sep66°FSep 4, 196027°FSep 17, 1965
Oct58°FOct 8, 19548°FOct 29, 2019
Nov48°FNov 15, 1941-3°FNov 15, 1955
Dec48°FDec 3, 1941-20°FDec 20, 1990
All-time74°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.
Jan: 36°FJan: 16°FFeb: 38°FFeb: 16°FMar: 49°FMar: 23°FApr: 56°FApr: 29°FMay: 67°FMay: 38°FJun: 80°FJun: 46°FJul: 89°FJul: 53°FAug: 87°FAug: 52°FSep: 76°FSep: 43°FOct: 60°FOct: 31°FNov: 46°FNov: 22°FDec: 35°FDec: 15°FJFMAMJJASOND

Sun & Location

Sun & Daylight Today

Sunrise5:30 AM
Sunset6:41 PM
Solar noon12:06 PM
Daylight13h 11m · losing 19 min/wk
Local standard time (no DST), level horizon.

Location

42.90°N, 106.47°W

Nearby Stations

Lander, WY114 mi WSheridan, WY131 mi NCheyenne, WY147 mi SEScottsbluff, NE162 mi ERapid City, SD188 mi EBillings, MT225 mi NW

The Last 6 Weeks

Casper's observed daily low for the last six weeks — a white ring marks any day that broke or tied its daily record for that date.
Casper, WY — last six weeks of daily low

2026 So Far

Every day this year against Casper's own record — the record low, the normal, and the full span ever seen. A shareable look at where the year stands.
Casper, WY — 2026 daily low trace
Download year chart

Every Day Since 1939

Each cell is one day's low at Casper, coloured by temperature — 88 years of record, so heat waves read as warm streaks and cold snaps as blue.
Casper, WY daily low heat map 1939–2026

Days Below the Mark

How many days a year hit a given low at Casper — counted through Sep 8 each year, so you can see whether 2026 is running cold. Pick a threshold:
97 days ≤32°F so far in 2026 — tied for the 79th most in 88 years. Normal for this point: 108. Record: 128 in 2022.

Share Card

A ready-to-share summary of Casper's outlook — post it, or link this page.
Casper, WY cold share card
Download card
See Casper on hottestsince.com →