Monthly outlook for Spearfish, SD: average high 58.9°, average low 40.6°. That is 1.6° above the climate normal for October. Precipitation is expected on 7 days (about 0.9 inches), against a normal of 4 days and 1.0 inches. The warmest day looks like 10 October (85.4°), the coolest 17 October (18.3°).
58.9°/40.6°
Average high / low
+1.6°
Above normal
7 / 4
Wet days / normal
0.9 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
10 October – 19 October
57.7°
56.5°
+0.6°
20 October – 29 October
60.9°
53.8°
+3.9°
30 October – 8 November
at normal
47.9°
—
October records over 66 years
86.9°4 October 1963All-time high
-5.4°30 October 1991All-time low
Climate normals and records are computed from the nearest reference point — Mountain Plains (3 mi).
Sun, 1160° / 46°0.09
60 °
Spearfish, Sunday, 11 October
Rain. High 60°, low 46°.
Pressure29.83 inHg
Wind4.5 mph NE
Humidity71%
Visibility6.2 mi
Dew point45°
Mon, 1253° / 40°0.02
53 °
Spearfish, Monday, 12 October
Light rain. High 53°, low 40°.
Pressure29.83 inHg
Wind3.2 mph NE
Humidity80%
Visibility6.2 mi
Dew point46°
Tue, 1348° / 37°0
48 °
Spearfish, Tuesday, 13 October
Light rain. High 48°, low 37°.
Pressure30.09 inHg
Wind3.7 mph E
Humidity75%
Visibility6.2 mi
Dew point38°
Wed, 1455° / 44°0
55 °
Spearfish, Wednesday, 14 October
Overcast. High 55°, low 44°.
Pressure30.24 inHg
Wind11.7 mph E
Humidity59%
Visibility—
Dew point37°
Thu, 1559° / 43°0.09
59 °
Spearfish, Thursday, 15 October
Light rain. High 59°, low 43°.
Pressure30.27 inHg
Wind11.9 mph W
Humidity62%
Visibility—
Dew point41°
Fri, 1639° / 27°0.13
39 °
Spearfish, Friday, 16 October
Light snow. High 39°, low 27°.
Pressure30.50 inHg
Wind31.3 mph NW
Humidity72%
Visibility—
Dew point22°
Sat, 1747° / 18°0.03
47 °
Spearfish, Saturday, 17 October
Light snow. High 47°, low 18°.
Pressure30.50 inHg
Wind14.1 mph NW
Humidity39%
Visibility—
Dew point15°
Sun, 1864° / 37°0
64 °
Spearfish, Sunday, 18 October
Partly cloudy. High 64°, low 37°.
Pressure29.91 inHg
Wind7.3 mph S
Humidity30%
Visibility—
Dew point28°
Mon, 1966° / 47°0
66 °
Spearfish, Monday, 19 October
Clear. High 66°, low 47°.
Pressure29.94 inHg
Wind7.8 mph S
Humidity21%
Visibility—
Dew point22°
Tue, 2070° / 47°0
70 °
Spearfish, Tuesday, 20 October
Overcast. High 70°, low 47°.
Pressure29.77 inHg
Wind14.2 mph SW
Humidity20%
Visibility—
Dew point25°
Wed, 2170° / 46°0.22
70 °
Spearfish, Wednesday, 21 October
Rain. High 70°, low 46°.
Pressure29.65 inHg
Wind17.1 mph SW
Humidity27%
Visibility—
Dew point33°
Thu, 2259° / 43°0.06
59 °
Spearfish, Thursday, 22 October
Light rain. High 59°, low 43°.
Pressure30.03 inHg
Wind13.9 mph SW
Humidity42%
Visibility—
Dew point30°
Fri, 2361° / 45°0.15
61 °
Spearfish, Friday, 23 October
Rain. High 61°, low 45°.
Pressure29.62 inHg
Wind20.2 mph W
Humidity33%
Visibility—
Dew point30°
Sat, 2443° / 35°0.05
43 °
Spearfish, Saturday, 24 October
Snow. High 43°, low 35°.
Pressure30.12 inHg
Wind18.9 mph NW
Humidity64%
Visibility—
Dew point29°
Sun, 2563° / 36°0
63 °
Spearfish, Sunday, 25 October
Overcast. High 63°, low 36°.
Pressure29.32 inHg
Wind20 mph SW
Humidity35%
Visibility—
Dew point31°
From day 17 onward the outlook is built from 60-year climate statistics
Mon, 2654° / 35°0.07
54 °
Spearfish, Monday, 26 October
Climate normal for this date — 60-year average.
Average high54°
Average low35°
Average precipitation0.07 in
Chance of precipitation22%
Record high72° (1960)
Record low-3° (2020)
Tue, 2752° / 33°0.05
52 °
Spearfish, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high52°
Average low33°
Average precipitation0.05 in
Chance of precipitation27%
Record high75° (2016)
Record low14° (2023)
Wed, 2852° / 34°0.06
52 °
Spearfish, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high52°
Average low34°
Average precipitation0.06 in
Chance of precipitation22%
Record high74° (2016)
Record low7° (1991)
Thu, 2950° / 33°0.11
50 °
Spearfish, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high50°
Average low33°
Average precipitation0.11 in
Chance of precipitation37%
Record high76° (1968)
Record low-2° (1991)
Fri, 3048° / 31°0.04
48 °
Spearfish, Friday, 30 October
Climate normal for this date — 60-year average.
Average high48°
Average low31°
Average precipitation0.04 in
Chance of precipitation27%
Record high73° (1968)
Record low-5° (1991)
Sat, 3148° / 31°0.05
48 °
Spearfish, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high48°
Average low31°
Average precipitation0.05 in
Chance of precipitation23%
Record high71° (1999)
Record low1° (1991)
Sun, 0148° / 31°0.08
48 °
Spearfish, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high48°
Average low31°
Average precipitation0.08 in
Chance of precipitation25%
Record high70° (1965)
Record low0° (2002)
Mon, 0247° / 31°0.05
47 °
Spearfish, Monday, 2 November
Climate normal for this date — 60-year average.
Average high47°
Average low31°
Average precipitation0.05 in
Chance of precipitation25%
Record high73° (2008)
Record low-8° (1991)
Tue, 0347° / 31°0.04
47 °
Spearfish, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high47°
Average low31°
Average precipitation0.04 in
Chance of precipitation23%
Record high71° (2020)
Record low-1° (1991)
Wed, 0450° / 31°0.02
50 °
Spearfish, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high50°
Average low31°
Average precipitation0.02 in
Chance of precipitation17%
Record high71° (1978)
Record low8° (1967)
Thu, 0548° / 31°0.04
48 °
Spearfish, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high48°
Average low31°
Average precipitation0.04 in
Chance of precipitation25%
Record high72° (2020)
Record low3° (2003)
Fri, 0648° / 30°0.06
48 °
Spearfish, Friday, 6 November
Climate normal for this date — 60-year average.
Average high48°
Average low30°
Average precipitation0.06 in
Chance of precipitation18%
Record high70° (2020)
Record low7° (1991)
Sat, 0748° / 30°0.04
48 °
Spearfish, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high48°
Average low30°
Average precipitation0.04 in
Chance of precipitation17%
Record high73° (1999)
Record low5° (1991)
Sun, 0846° / 30°0.06
46 °
Spearfish, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high46°
Average low30°
Average precipitation0.06 in
Chance of precipitation22%
Record high74° (1999)
Record low7° (2000)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Spearfish, SD are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Spearfish, SD since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.