Monthly outlook for Spearfish, SD: average high 58.5°, average low 40°. That is 1.4° above the climate normal for October. Precipitation is expected on 3 days (about 0.8 inches), against a normal of 4 days and 1.0 inches. The warmest day looks like 10 October (83.6°), the coolest 17 October (22.6°).
58.5°/40°
Average high / low
+1.4°
Above normal
3 / 4
Wet days / normal
0.8 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
10 October – 19 October
59.5°
56.5°
+1.6°
20 October – 29 October
56.9°
53.8°
+1.7°
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, 1161° / 44°0.03
61 °
Spearfish, Sunday, 11 October
Light rain. High 61°, low 44°.
Pressure29.83 inHg
Wind3.9 mph NE
Humidity75%
Visibility6.2 mi
Dew point45°
Mon, 1248° / 40°0.03
48 °
Spearfish, Monday, 12 October
Light rain. High 48°, low 40°.
Pressure29.88 inHg
Wind6.2 mph W
Humidity88%
Visibility4.6 mi
Dew point46°
Tue, 1349° / 34°0.05
49 °
Spearfish, Tuesday, 13 October
Light rain. High 49°, low 34°.
Pressure30.09 inHg
Wind5.2 mph E
Humidity79%
Visibility6.2 mi
Dew point40°
Wed, 1456° / 40°0
56 °
Spearfish, Wednesday, 14 October
Overcast. High 56°, low 40°.
Pressure30.21 inHg
Wind11.5 mph E
Humidity57%
Visibility—
Dew point36°
Thu, 1555° / 43°0.13
55 °
Spearfish, Thursday, 15 October
Rain. High 55°, low 43°.
Pressure30.33 inHg
Wind7 mph SW
Humidity72%
Visibility—
Dew point40°
Fri, 1645° / 26°0
45 °
Spearfish, Friday, 16 October
Mostly clear. High 45°, low 26°.
Pressure30.65 inHg
Wind25.9 mph NW
Humidity34%
Visibility—
Dew point10°
Sat, 1761° / 23°0
61 °
Spearfish, Saturday, 17 October
Clear. High 61°, low 23°.
Pressure30.27 inHg
Wind7.5 mph NE
Humidity11%
Visibility—
Dew point-5°
Sun, 1866° / 46°0
66 °
Spearfish, Sunday, 18 October
Overcast. High 66°, low 46°.
Pressure29.94 inHg
Wind8.2 mph S
Humidity20%
Visibility—
Dew point21°
Mon, 1970° / 50°0
70 °
Spearfish, Monday, 19 October
Mostly clear. High 70°, low 50°.
Pressure29.80 inHg
Wind7.6 mph N
Humidity21%
Visibility—
Dew point26°
Tue, 2053° / 38°0.6
53 °
Spearfish, Tuesday, 20 October
Rain. High 53°, low 38°.
Pressure29.80 inHg
Wind21.5 mph NW
Humidity96%
Visibility—
Dew point40°
Wed, 2158° / 35°0
58 °
Spearfish, Wednesday, 21 October
Mostly clear. High 58°, low 35°.
Pressure29.97 inHg
Wind14.3 mph W
Humidity38%
Visibility—
Dew point27°
Thu, 2256° / 38°0
56 °
Spearfish, Thursday, 22 October
Clear. High 56°, low 38°.
Pressure30.15 inHg
Wind8 mph S
Humidity31%
Visibility—
Dew point21°
Fri, 2364° / 42°0
64 °
Spearfish, Friday, 23 October
Overcast. High 64°, low 42°.
Pressure29.91 inHg
Wind6.3 mph S
Humidity30%
Visibility—
Dew point29°
Sat, 2462° / 50°0
62 °
Spearfish, Saturday, 24 October
Partly cloudy. High 62°, low 50°.
Pressure30.00 inHg
Wind14.8 mph NW
Humidity34%
Visibility—
Dew point32°
Sun, 2548° / 33°0
48 °
Spearfish, Sunday, 25 October
Overcast. High 48°, low 33°.
Pressure30.53 inHg
Wind13.2 mph NW
Humidity73%
Visibility—
Dew point30°
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.