Monthly outlook for Arpan, SD: average high 62.6°, average low 44.2°. That is 2.2° above the climate normal for October. Precipitation is expected on 3 days (about 0.3 inches), against a normal of 3 days and 0.7 inches. The warmest day looks like 18 October (75.8°), the coolest 17 October (31°).
62.6°/44.2°
Average high / low
+2.2°
Above normal
3 / 3
Wet days / normal
0.3 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
11 October – 20 October
62°
59.4°
+1.4°
21 October – 30 October
63.6°
55.8°
+4.3°
31 October – 9 November
at normal
49.9°
—
October records over 66 years
92.5°4 October 1963All-time high
-5.8°26 October 2020All-time low
Mon, 1254° / 43°0.04
54 °
Arpan, Monday, 12 October
Light rain. High 54°, low 43°.
Pressure29.91 inHg
Wind17.5 mph NW
Humidity73%
Visibility6.2 mi
Dew point43°
Tue, 1356° / 42°0.04
56 °
Arpan, Tuesday, 13 October
Light rain. High 56°, low 42°.
Pressure30.06 inHg
Wind4.1 mph SE
Humidity77%
Visibility1.9 mi
Dew point39°
Wed, 1457° / 47°0.03
57 °
Arpan, Wednesday, 14 October
Light rain. High 57°, low 47°.
Pressure30.21 inHg
Wind6.5 mph SE
Humidity54%
Visibility6.2 mi
Dew point38°
Thu, 1561° / 47°0.17
61 °
Arpan, Thursday, 15 October
Rain. High 61°, low 47°.
Pressure30.39 inHg
Wind13.2 mph N
Humidity82%
Visibility—
Dew point46°
Fri, 1656° / 34°0
56 °
Arpan, Friday, 16 October
Clear. High 56°, low 34°.
Pressure30.62 inHg
Wind11.5 mph SE
Humidity46%
Visibility—
Dew point29°
Sat, 1760° / 31°0
60 °
Arpan, Saturday, 17 October
Clear. High 60°, low 31°.
Pressure30.24 inHg
Wind16.5 mph SE
Humidity20%
Visibility—
Dew point11°
Sun, 1876° / 48°0
76 °
Arpan, Sunday, 18 October
Overcast. High 76°, low 48°.
Pressure29.91 inHg
Wind14.8 mph NW
Humidity16%
Visibility—
Dew point23°
Mon, 1973° / 50°0
73 °
Arpan, Monday, 19 October
Overcast. High 73°, low 50°.
Pressure29.85 inHg
Wind5.7 mph E
Humidity23%
Visibility—
Dew point27°
Tue, 2066° / 53°0
66 °
Arpan, Tuesday, 20 October
Partly cloudy. High 66°, low 53°.
Pressure29.85 inHg
Wind14 mph W
Humidity35%
Visibility—
Dew point34°
Wed, 2163° / 48°0
63 °
Arpan, Wednesday, 21 October
Clear. High 63°, low 48°.
Pressure30.12 inHg
Wind13.1 mph NW
Humidity23%
Visibility—
Dew point21°
Thu, 2266° / 44°0
66 °
Arpan, Thursday, 22 October
Overcast. High 66°, low 44°.
Pressure30.09 inHg
Wind17.7 mph SE
Humidity38%
Visibility—
Dew point30°
Fri, 2364° / 50°0
64 °
Arpan, Friday, 23 October
Mostly clear. High 64°, low 50°.
Pressure30.00 inHg
Wind26.7 mph NW
Humidity43%
Visibility—
Dew point37°
Sat, 2456° / 40°0
56 °
Arpan, Saturday, 24 October
Overcast. High 56°, low 40°.
Pressure30.42 inHg
Wind11.1 mph W
Humidity32%
Visibility—
Dew point22°
Sun, 2567° / 39°0
67 °
Arpan, Sunday, 25 October
Clear. High 67°, low 39°.
Pressure30.27 inHg
Wind16.4 mph NW
Humidity21%
Visibility—
Dew point21°
Mon, 2666° / 45°0
66 °
Arpan, Monday, 26 October
Clear. High 66°, low 45°.
Pressure30.18 inHg
Wind8.7 mph SE
Humidity29%
Visibility—
Dew point27°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2755° / 35°0.03
55 °
Arpan, Tuesday, 27 October
Climate normal for this date — 60-year average.
Average high55°
Average low35°
Average precipitation0.03 in
Chance of precipitation23%
Record high77° (2016)
Record low9° (2020)
Wed, 2855° / 35°0.05
55 °
Arpan, Wednesday, 28 October
Climate normal for this date — 60-year average.
Average high55°
Average low35°
Average precipitation0.05 in
Chance of precipitation18%
Record high80° (1985)
Record low13° (1991)
Thu, 2953° / 34°0.1
53 °
Arpan, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high53°
Average low34°
Average precipitation0.1 in
Chance of precipitation28%
Record high78° (1968)
Record low3° (1991)
Fri, 3051° / 33°0.03
51 °
Arpan, Friday, 30 October
Climate normal for this date — 60-year average.
Average high51°
Average low33°
Average precipitation0.03 in
Chance of precipitation20%
Record high78° (1968)
Record low-5° (1991)
Sat, 3151° / 33°0.04
51 °
Arpan, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high51°
Average low33°
Average precipitation0.04 in
Chance of precipitation17%
Record high77° (1999)
Record low-2° (1991)
Sun, 0151° / 33°0.06
51 °
Arpan, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high51°
Average low33°
Average precipitation0.06 in
Chance of precipitation17%
Record high74° (1965)
Record low0° (2002)
Mon, 0251° / 32°0.02
51 °
Arpan, Monday, 2 November
Climate normal for this date — 60-year average.
Average high51°
Average low32°
Average precipitation0.02 in
Chance of precipitation20%
Record high75° (1965)
Record low-4° (1991)
Tue, 0350° / 33°0.03
50 °
Arpan, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high50°
Average low33°
Average precipitation0.03 in
Chance of precipitation17%
Record high72° (2020)
Record low-2° (1991)
Wed, 0452° / 31°0.01
52 °
Arpan, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high52°
Average low31°
Average precipitation0.01 in
Chance of precipitation12%
Record high78° (1978)
Record low6° (1991)
Thu, 0550° / 32°0.03
50 °
Arpan, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high50°
Average low32°
Average precipitation0.03 in
Chance of precipitation20%
Record high73° (2020)
Record low6° (2003)
Fri, 0650° / 30°0.04
50 °
Arpan, Friday, 6 November
Climate normal for this date — 60-year average.
Average high50°
Average low30°
Average precipitation0.04 in
Chance of precipitation12%
Record high72° (2009)
Record low1° (2003)
Sat, 0750° / 31°0.03
50 °
Arpan, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high50°
Average low31°
Average precipitation0.03 in
Chance of precipitation12%
Record high76° (1999)
Record low-4° (1991)
Sun, 0848° / 30°0.04
48 °
Arpan, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high48°
Average low30°
Average precipitation0.04 in
Chance of precipitation23%
Record high79° (1999)
Record low6° (2000)
Mon, 0945° / 28°0.06
45 °
Arpan, Monday, 9 November
Climate normal for this date — 60-year average.
Average high45°
Average low28°
Average precipitation0.06 in
Chance of precipitation22%
Record high71° (2001)
Record low2° (1966)
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 Arpan, 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 Arpan, 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.