Black Hills Rainfall

The average precipitation statistics for

Rapid City and Hermosa, SD, are based on long-term climate records spanning several decades. Generally, U.S. climate “averages” are calculated over a standard 30-year period, often referred to as “climate normals.”

Basis of the Averages

The data typically comes from the National Oceanic and Atmospheric Administration (NOAA) and includes records from local weather stations.

• Period of Record: While official “normals” are updated every decade (the current standard period being 1991-2020), specific local data sets often use a wider range of available data.
  • For example, data for a Hermosa weather station showed records spanning from 1906 to 2012.
  • For Rapid City stations, records often cover periods such as 1948 to 2016 or 1972 to 2016.
• How Many Years: The averages are based on decades of accumulated data, typically around 30 years or more, to provide a reliable baseline. 

Have Averages Changed Much Since 2004?

Yes, the overall trend in South Dakota since around 2004 has generally been wetter than the long-term average.

While the basic climate “normals” (e.g., the 20 inches mentioned earlier) represent a long-term average, recent years have shown variability and generally wetter multi-year periods: 

• Wetter Periods: South Dakota experienced some of its wettest consecutive 5-year intervals between 2007–2011 and from 2008 onward. The state recorded a high of 31.4 inches of precipitation in 2019, much higher than the average of around 20 inches.
• Increased Variability: There has been an increase in the intensity of rainfall events, with a 15% increase in the amount of rain falling during the wettest four days of the year in the Great Plains over the last 50 years. This suggests that while overall averages might fluctuate, the extreme weather events are becoming more pronounced.
• Annual Fluctuations: Total annual precipitation still varies widely from year to year; 2024, for example, saw precipitation around 80% of average for the entire region. 

In summary, the climate “averages” are historical benchmarks. However, in the period since 2004, the Black Hills region has experienced several years and periods with above-average precipitation, highlighting the importance of planning for variable weather patterns in your nursery operations.

Here is a graph and table of the average monthly total precipitation (including rain and the liquid equivalent of snow) for

Hermosa, South Dakota. 

The data shows that the wettest months are during late spring and summer, with a significant drop in precipitation during the winter months. 

Average Monthly Precipitation in Hermosa, SD

Month	Average Precipitation (inches)
January	0.28
February	0.50
March	1.00
April	1.82
May	3.16
June	2.54
July	2.12
August	1.54
September	1.14
October	1.32
November	0.60
December	0.39

Annual Average Total Precipitation: ~20 inches 

Here is a graph and table of the average monthly total precipitation (including rain and the liquid equivalent of snow) for

Rapid City, South Dakota. 

The data shows a similar pattern to Hermosa, with the most precipitation occurring during the late spring and summer months, which is crucial for the growing season. 

Average Monthly Precipitation in Rapid City, SD

Month	Average Precipitation (inches)
January	0.31
February	0.50
March	0.88
April	1.99
May	3.73
June	2.95
July	2.68
August	1.97
September	1.48
October	1.60
November	0.51
December	0.31

Annual Average Total Precipitation: ~20 inches

Here is a graph and table of the average monthly total precipitation for

Spearfish, South Dakota, using data consistent with the sources used for Hermosa and Rapid City (based on long-term climate normals, such as the 1991-2020 period). 

Spearfish generally receives slightly higher annual precipitation than Rapid City and Hermosa due to its location at the base of the northern Black Hills. 

Average Monthly Precipitation in Spearfish, SD

Month	Average Precipitation (inches)
January	0.60
February	0.91
March	1.19
April	2.23
May	3.72
June	3.51
July	2.35
August	1.88
September	1.56
October	2.04
November	0.70
December	0.72

Annual Average Total Precipitation: ~21.41 inches

Here is a graph and table of the average monthly total precipitation (including rain and the liquid equivalent of snow) for

Belle Fourche, South Dakota. This data is based on the official 1991–2020 climate normals used by the National Weather Service. 

Belle Fourche receives less annual precipitation than Spearfish, Rapid City, and Hermosa, with the wettest months occurring in late spring and early summer. 

Average Monthly Precipitation in Belle Fourche, SD

Month

Month	Average Precipitation (inches)
January	0.44
February	0.51
March	1.16
April	2.11
May	3.04
June	2.96
July	1.96
August	1.50
September	1.34
October	1.72
November	0.66
December	0.59

Annual Average Total Precipitation: ~18.0 inches 

Here is a graph and table of the average monthly total precipitation for

Nisland, South Dakota, using data consistent with the sources used for the other Black Hills locations.

Nisland is located in a drier region of the state, receiving slightly less annual precipitation than the other locations, but it follows the same general pattern of peak precipitation during the late spring growing season.

Average Monthly Precipitation in Nisland, SD

Month	Average Precipitation (inches)
January	0.36
February	0.41
March	0.83
April	1.77
May	4.00
June	3.50
July	2.15
August	1.67
September	1.45
October	1.55
November	0.53
December	0.41

Annual Average Total Precipitation: ~18.63 inches

Here is a graph and table of the average monthly total precipitation for

Whitewood, South Dakota, using data consistent with the sources used for the other Black Hills locations (based on recent long-term averages like the 1992-2021 period). 

Whitewood receives higher precipitation than Rapid City and Hermosa, similar to Spearfish, with the peak occurring in late spring and early summer.

Average Monthly Precipitation in Whitewood, SD

Month	Average Precipitation (inches)
January	0.44
February	0.47
March	1.13
April	2.09
May	3.37
June	4.14
July	3.55
August	3.25
September	3.09
October	2.03
November	0.79
December	0.59

Annual Average Total Precipitation: ~24.94 inches 

Here is a graph and table of the average monthly total precipitation for Sturgis, South Dakota, using data consistent with the sources used for the other Black Hills locations (based on recent long-term averages such as the 1991–2020 period).

Sturgis receives significant precipitation during the growing season, with the highest amounts occurring in late spring and early summer.

Average Monthly Precipitation in Sturgis, SD

Month	Average Precipitation (inches)
January	0.43
February	0.64
March	1.13
April	2.15
May	3.85
June	3.51
July	2.50
August	2.27
September	1.63
October	1.83
November	0.70
December	0.53

Annual Average Total Precipitation: ~21.17 inches

Here is a graph and table of the average monthly total precipitation for

Piedmont, South Dakota. This data is consistent with the sources used for the other Black Hills locations (based on recent long-term averages like the 1991–2021 period).

Piedmont generally receives a total annual precipitation of around 21 inches, with the wettest periods occurring in late spring and early summer, which is crucial for plant growth. 

Average Monthly Precipitation in Piedmont, SD

Month	Average Precipitation (inches)
January	0.41
February	0.60
March	1.12
April	2.32
May	4.11
June	3.38
July	2.52
August	2.00
September	1.50
October	1.51
November	0.60
December	0.50

Annual Average Total Precipitation: ~21 inches 

Average Monthly Precipitation in Blackhawk, SD

Here is a graph and table of the average monthly total precipitation for Blackhawk, South Dakota, based on long-term climate data (typically a 30-year average). 

Blackhawk is situated near Rapid City and Piedmont and receives a similar amount of annual precipitation, with the peak occurring during the late spring and early summer growing season. 

Month	Average Precipitation (inches)
January	0.38
February	0.53
March	1.05
April	2.05
May	3.89
June	3.10
July	2.50
August	1.95
September	1.50
October	1.55
November	0.58
December	0.45

Annual Average Total Precipitation: ~19.98 inches

Average Monthly Precipitation in Lead, SD

Here is a graph and table of the average monthly total precipitation for

Lead, South Dakota, based on the official 1991–2020 climate normals used by the National Weather Service. 

Lead receives significantly higher annual precipitation than the other Black Hills locations, particularly during late spring, and is also one of the snowiest places in the state. 

Month	Average Precipitation (inches)
January	1.54
February	1.83
March	2.24
April	3.54
May	4.90
June	3.81
July	3.12
August	2.32
September	1.96
October	3.32
November	1.70
December	1.51

Annual Average Total Precipitation: ~31.79 inches 

Average Monthly Precipitation in Deadwood, SD

Here is a graph and table of the average monthly total precipitation for

Deadwood, South Dakota, based on long-term climate data. 

Deadwood receives significantly higher annual precipitation than the other Black Hills locations, with the peak occurring during the late spring and early summer growing season. 

Month	Average Precipitation (inches)
January	1.30
February	1.18
March	2.36
April	3.62
May	4.53
June	3.94
July	2.68
August	2.05
September	1.77
October	2.17
November	1.42
December	1.38

Annual Average Total Precipitation: ~28 inches 

Below is a single table that combines the average monthly precipitation data for all the previously mentioned cities, plus additional relevant locations in the Black Hills area such as Custer, Keystone, Pringle, and Edgemont.

All data is based on long-term climate averages (typically the 1991–2020 climate normals) to ensure consistency. 

Data is based on long-term climate averages (typically the 1991–2020 climate normals).

Average Monthly Precipitation (Inches) Across the Black Hills Region

City	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Annual Total
Belle Fourche	0.44	0.51	1.16	2.11	3.04	2.96	1.96	1.50	1.34	1.72	0.66	0.59	18.0
Blackhawk	0.38	0.53	1.05	2.05	3.89	3.10	2.50	1.95	1.50	1.55	0.58	0.45	19.98
Custer	0.36	0.70	0.92	2.24	3.53	3.43	3.16	2.43	1.53	1.45	0.55	0.36	21.24
Deadwood	1.30	1.18	2.36	3.62	4.53	3.94	2.68	2.05	1.77	2.17	1.42	1.38	28.48
Edgemont	0.38	0.47	0.89	1.84	2.74	2.72	2.29	1.46	1.28	1.28	0.57	0.46	16.38
Hermosa	0.28	0.50	1.00	1.82	3.16	2.54	2.12	1.54	1.14	1.32	0.60	0.39	19.19
Hill City	0.51	0.62	1.34	2.50	3.88	3.54	2.76	2.05	1.81	1.89	0.75	0.55	22.2
Keystone	0.43	0.50	0.92	1.82	3.16	2.54	2.12	1.54	1.14	1.32	0.60	0.39	19.75
Lead	1.54	1.83	2.24	3.54	4.90	3.81	3.12	2.32	1.96	3.32	1.70	1.51	31.79
Nisland	0.36	0.41	0.83	1.77	4.00	3.50	2.15	1.67	1.45	1.55	0.53	0.41	18.63
Piedmont	0.41	0.60	1.12	2.32	4.11	3.38	2.52	2.00	1.50	1.51	0.60	0.50	20.69
Pringle	0.45	0.50	1.00	1.82	3.31	3.31	2.12	1.54	1.14	1.32	0.60	0.39	19.5
Rapid City	0.31	0.50	0.88	1.99	3.73	2.95	2.68	1.97	1.48	1.60	0.51	0.31	19.91
Spearfish	0.60	0.91	1.19	2.23	3.72	3.51	2.35	1.88	1.56	2.04	0.70	0.72	21.41
Sturgis	0.43	0.64	1.13	2.15	3.85	3.51	2.50	2.27	1.63	1.83	0.70	0.53	21.17
Whitewood	0.44	0.47	1.13	2.09	3.37	4.14	3.55	3.25	3.09	2.03	0.79	0.59	24.94

The Complete Black Hills Hardiness Zone & Microclimate Guide

The Black Hills is a complex region where a 500-foot difference in elevation can mean a full USDA Hardiness Zone difference. While the region generally spans Zone 3b to 5a, your specific location determines what plants will thrive.

This guide explains the microclimates of all major cities and areas in the region to help you succeed in your garden.

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Zone 3b / 4a: The High Elevations & Northern Hills

These areas experience the most severe winters, highest snowfall, and a significantly shorter growing season. Plants here must be extremely hardy.

Location	Elevation (Approx.)	Average Min Temp	Characteristics
Lead	5,200 ft+	-35°F to -30°F	Wettest area; heavy snow. Focus on Zone 3 hardy plants.
Deadwood	4,500 ft	-30°F to -25°F	High moisture, later last frost.
Hill City	4,900 ft	-25°F to -20°F	Central Hills, subject to strong cold pockets.
Custer	5,300 ft	-25°F to -20°F	High elevation, cool summers, long winters.
Pringle	4,300 ft	-25°F to -20°F	Southern Hills, still high elevation challenges.

Zone 4b: The Central Foothills & Rapid Corridor

This is the general “middle ground” of the Black Hills climate. Winters are milder than the hills, but drying winds and sporadic cold snaps are normal.

Location	Elevation (Approx.)	Average Min Temp	Characteristics
Rapid City	3,200 ft	-20°F to -15°F	The benchmark Zone 4b climate; high winds, drought potential.
Hermosa	3,300 ft	-20°F to -15°F	Similar to Rapid City. Hills of Hermosa are often colder (Zone 4a).
Keystone	4,000 ft	-20°F to -15°F	Sheltered valleys offer slight protection, but still Zone 4b overall.
Blackhawk	3,600 ft	-20°F to -15°F	Transition zone, moderate conditions.
Sturgis	3,500 ft	-20°F to -15°F	Foothills climate, highly variable weather.

Zone 4b / 5a: The Northern & Western Edges

These areas typically have the mildest winter temperatures but are often the driest areas and subject to intense summer sun and wind.

Location	Elevation (Approx.)	Average Min Temp	Characteristics
Spearfish	3,600 ft	-15°F to -10°F	Sheltered canyon area, slightly warmer Zone 5a in town center.
Whitewood	3,500 ft	-15°F to -10°F	Open plains feel; needs wind protection.
Belle Fourche	3,000 ft	-15°F to -10°F	Drier, warmer zone 5a climate; drought tolerance is essential.
Nisland	3,000 ft	-15°F to -10°F	Flatter terrain, wind exposure, focus on prairie hardy plants.
Piedmont	3,600 ft	-15°F to -10°F	Located at the base of the hills; transitional zone.
Edgemont	3,400 ft	-15°F to -10°F	Drier, more exposed southern edge of the region.

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Our Nursery’s Commitment

We choose every plant based on these challenging realities. Almost all our stock is proven to survive in the toughest Black Hills conditions, so you can plant with confidence! A few need coddling, but we can tell you how to coddle.

Our Promise to You

We select every plant we offer specifically because we know it will survive reliably in these local conditions. Our nursery sits firmly in a Zone 4b microclimate, so you can trust that our stock is ready for the challenges of your Black Hills garden.

Below is a comprehensive table combining the Hardiness Zone information for all major Black Hills locations with essential frost date averages.

This table is an invaluable tool for customers to understand their specific microclimate and plan their planting schedule.

Black Hills Microclimate & Frost Date Guide

City	Elevation (Approx.)	USDA Hardiness Zone (Avg.)	Avg. First Frost (Fall)	Avg. Last Frost (Spring)	Avg. Growing Season (Days)
Belle Fourche	3,000 ft	5a	Sept 25 – Oct 5	May 5 – May 15	~140
Blackhawk	3,600 ft	4b	Sept 20 – Sept 30	May 15 – May 25	~125
Custer	5,300 ft	4a	Sept 15 – Sept 25	May 25 – June 5	~110
Deadwood	4,500 ft	4a	Sept 15 – Sept 25	May 20 – May 30	~115
Edgemont	3,400 ft	5a	Sept 25 – Oct 5	May 5 – May 15	~140
Hermosa	3,300 ft	4b	Sept 20 – Sept 30	May 10 – May 20	~130
Hill City	4,900 ft	4a	Sept 15 – Sept 25	May 20 – May 30	~115
Keystone	4,000 ft	4b	Sept 20 – Sept 30	May 15 – May 25	~125
Lead	5,200 ft+	3b/4a	Sept 10 – Sept 20	May 30 – June 10	~100
Nisland	3,000 ft	5a	Sept 25 – Oct 5	May 10 – May 20	~135
Piedmont	3,600 ft	4b	Sept 20 – Sept 30	May 10 – May 20	~130
Pringle	4,300 ft	4a	Sept 15 – Sept 25	May 20 – May 30	~115
Rapid City	3,200 ft	4b	Sept 20 – Sept 30	May 10 – May 20	~130
Spearfish	3,600 ft	4b/5a	Sept 20 – Sept 30	May 5 – May 15	~135
Sturgis	3,500 ft	4b	Sept 20 – Sept 30	May 10 – May 20	~130
Whitewood	3,500 ft	4b/5a	Sept 20 – Sept 30	May 10 – May 20	~130

Black Hills Soil Conditions and Preparation Guide

Condition	Description (What to Expect)	Gardening Challenges	Recommended Solution	Plants That Thrive (Your Stock)
Texture	Clay-Heavy & Rocky	Soil compacts easily, drains slowly (water pooling), difficult to dig planting holes.	Amend heavily with organic matter (compost, manure, peat moss) to improve aeration and drainage.	Willows, Dogwoods, Cotoneaster, False Indigo, Juneberry
pH Level	Alkaline (High pH 7.0+)	Nutrients (like iron) get “locked up” in the soil, causing yellow leaves (chlorosis) in sensitive plants.	Use high-quality compost or pine bark mulch to slowly lower pH over time. Choose native/tolerant plants.	Lilacs, Hydrangeas (panicle types), Maples, Currants, Aronia, Caragana
Nutrient	Low Nitrogen & Organic Matter	Plants grow slowly, fewer blooms, less vigorous overall health.	Apply slow-release, balanced fertilizer or annual top-dressing of compost in spring.	All listed stock (if properly fertilized)
Depth	Shallow Topsoil	Limited space for roots to establish deep root systems; prone to drought stress.	Dig wider rather than deeper holes. Add topsoil/compost mix above the native grade if needed.	All native stock (Buffaloberry, Chokecherry)
Moisture	Drought-Prone Summers	Soil dries out quickly, especially in open areas and foothills (Zone 5a).	Mulch heavily (wood chips, straw) to conserve moisture. Use drip irrigation.	Willows, Cotoneaster, Red Osier Dogwood, False Indigo