10-day forecast for Keystone, SD: 57° to 96°, with precipitation expected on 0 days. The table below breaks each day into morning, afternoon, evening and overnight.
96°
Best day: Monday, August 10
73°
Worst day: Thursday, August 13
Tap any day below to see morning, afternoon, evening and overnight.
Sun, 0986° / 63°0
Morning69°feels 67°
Afternoon85°feels 82°
Evening77°feels 76°
Overnight66°feels 64°
86 °
Keystone, Sunday, 9 August
Overcast. High 86°, low 63°.
Pressure29.83 inHg
Wind11.9 mph E
Humidity25%
Visibility6.2 mi
Dew point45°
Mon, 1096° / 61°0
Morning77°feels 76°
Afternoon96°feels 92°
Evening78°feels 77°
Overnight64°feels 63°
96 °
Keystone, Monday, 10 August
Mostly clear. High 96°, low 61°.
Pressure29.77 inHg
Wind10.6 mph E
Humidity24%
Visibility6.2 mi
Dew point48°
Tue, 1187° / 62°0.02
Morning78°feels 77°
Afternoon86°feels 84°
Evening70°feels 70°
Overnight63°feels 62°
87 °
Keystone, Tuesday, 11 August
Light rain. High 87°, low 62°.
Pressure29.85 inHg
Wind10.6 mph E
Humidity35%
Visibility6.2 mi
Dew point53°
Wed, 1288° / 62°0.03
Morning75°feels 74°
Afternoon87°feels 84°
Evening75°feels 75°
Overnight63°feels 63°
88 °
Keystone, Wednesday, 12 August
Light rain. High 88°, low 62°.
Pressure29.77 inHg
Wind13.7 mph SE
Humidity27%
Visibility6.2 mi
Dew point51°
Thu, 1373° / 57°0.03
Morning59°feels 59°
Afternoon66°feels 66°
Evening72°feels 72°
Overnight65°feels 64°
73 °
Keystone, Thursday, 13 August
Light rain. High 73°, low 57°.
Pressure30.06 inHg
Wind12.3 mph SE
Humidity77%
Visibility—
Dew point56°
Fri, 1488° / 61°0.01
Morning68°feels 68°
Afternoon82°feels 82°
Evening80°feels 79°
Overnight65°feels 65°
88 °
Keystone, Friday, 14 August
Light rain. High 88°, low 61°.
Pressure29.91 inHg
Wind18.3 mph S
Humidity41%
Visibility—
Dew point53°
Sat, 1583° / 61°0
Morning67°feels 66°
Afternoon81°feels 80°
Evening80°feels 79°
Overnight68°feels 67°
83 °
Keystone, Saturday, 15 August
Overcast. High 83°, low 61°.
Pressure30.03 inHg
Wind10.9 mph NE
Humidity39%
Visibility—
Dew point51°
Sun, 1691° / 66°0
Morning73°feels 72°
Afternoon90°feels 87°
Evening81°feels 79°
Overnight70°feels 69°
91 °
Keystone, Sunday, 16 August
Clear. High 91°, low 66°.
Pressure29.94 inHg
Wind10.2 mph NE
Humidity20%
Visibility—
Dew point42°
Mon, 1789° / 66°0.01
Morning72°feels 70°
Afternoon86°feels 84°
Evening80°feels 80°
Overnight70°feels 69°
89 °
Keystone, Monday, 17 August
Light rain. High 89°, low 66°.
Pressure29.97 inHg
Wind12.4 mph SE
Humidity31%
Visibility—
Dew point50°
About this forecast
How reliable is a 10-day forecast?
The first 3–5 days are the most reliable, typically within 2–4°. From day six to ten the models show the trend: the direction of change is right more often than the exact numbers.
What does the time-of-day table show?
Temperature in Keystone, SD around 8am, 2pm, 8pm and 2am each day — handy for planning a walk, a drive or work outdoors.
How is the best day chosen?
We weigh the daytime high against precipitation: a warm, dry day scores highest.