Climate snapshot for alpacas
89/100Alpaca climate comfort score
83°FAverage high, Jul
12°FAverage low, Jan
~7Days above 90°F (32°C) per year
~189Frost nights per year
17 inAnnual precipitation
1Barber pole worm months
17Hay bales / alpaca / year
Main challenges
- Hard winters — average lows under 15 °F in Dec–Feb
Advantages
- Summers rarely reach heat-stress levels for alpacas
- Short or no barber pole worm transmission season
- Low meningeal worm risk
Overall rating: 89/100 — Excellent on our alpaca climate comfort score. Climate type: Warm-summer humid continental (Köppen Dfb).
Month-by-month climate
Average highAverage lowPrecipitation
| Month | High | Low | Precip. | Heat-stress index | Notes |
|---|---|---|---|---|---|
| Jan | 35°F | 12°F | 0.6 in | 95 · ok | frost |
| Feb | 37°F | 14°F | 0.5 in | 104 · ok | frost |
| Mar | 46°F | 22°F | 0.8 in | 107 · ok | frost |
| Apr | 55°F | 30°F | 1.8 in | 106 · ok | frost |
| May | 64°F | 39°F | 3.0 in | 120 · ok | grass |
| Jun | 73°F | 47°F | 3.2 in | 125 · ok | worms, grass |
| Jul | 83°F | 53°F | 1.7 in | 124 · caution | grass |
| Aug | 82°F | 51°F | 1.4 in | 130 · caution | grass |
| Sep | 71°F | 42°F | 1.4 in | 119 · ok | grass |
| Oct | 57°F | 32°F | 1.3 in | 100 · ok | frost |
| Nov | 44°F | 21°F | 0.7 in | 105 · ok | frost |
| Dec | 35°F | 14°F | 0.6 in | 90 · ok | frost |
Heat-stress index = average high (°F) + mean humidity (%). “Worms” marks months that suit barber pole worm transmission; “grass” marks the grazing season; “frost” marks months with average lows below freezing. Source: NOAA nClimDiv 1991–2020 county normals.
Alpaca care calendar for Fergus County, Montana
January 35° / 12°F
- Hard cold: extra hay at night, heated water, windbreaks and coats for crias or seniors; check ears for frostbite.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
- Toenail check and trim.
February 37° / 14°F
- Hard cold: extra hay at night, heated water, windbreaks and coats for crias or seniors; check ears for frostbite.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
March 46° / 22°F
- Book your shearer now — spring calendars fill up fast.
- Freezing nights: keep water open and feed extra hay during cold snaps.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
- Toenail check and trim.
April 55° / 30°F
- CDT boosters for females due next month; prepare a clean birthing paddock and birthing kit.
- Freezing nights: keep water open and feed extra hay during cold snaps.
May 64° / 39°F
- Shearing month: shear the whole herd, and trim toenails, check teeth and body condition while animals are restrained.
- Run pre-season fecal egg counts so you know each animal's baseline.
- Cria season: check due dates daily, ensure crias nurse within 4 hours, dip navels and weigh crias daily for two weeks.
- Spring grass: switch from hay to pasture gradually over 1–2 weeks and monitor body condition.
- Toenail check and trim.
June 73° / 47°F
- Barber pole worm season: fecal egg counts every 4–6 weeks, check eyelid color, pick up dung piles twice a week.
- Cria season: check due dates daily, ensure crias nurse within 4 hours, dip navels and weigh crias daily for two weeks.
- Breeding window for next year's crias (rebreed females 2–4 weeks after birthing).
July 83° / 53°F
- Warm spells possible — watch for open-mouth breathing in heavy-fleeced or dark animals.
- Cria season: check due dates daily, ensure crias nurse within 4 hours, dip navels and weigh crias daily for two weeks.
- Breeding window for next year's crias (rebreed females 2–4 weeks after birthing).
- Fly season: clean dung piles regularly and use traps around the barn.
- Toenail check and trim.
August 82° / 51°F
- Warm spells possible — watch for open-mouth breathing in heavy-fleeced or dark animals.
- Cria season: check due dates daily, ensure crias nurse within 4 hours, dip navels and weigh crias daily for two weeks.
- Breeding window for next year's crias (rebreed females 2–4 weeks after birthing).
- Fly season: clean dung piles regularly and use traps around the barn.
September 71° / 42°F
- Breeding window for next year's crias (rebreed females 2–4 weeks after birthing).
- Secure winter hay: about 17 small square bales per alpaca per year here — test a sample before buying.
- Winter prep: install water heaters, repair shelters and windbreaks, stock bedding.
- Fly season: clean dung piles regularly and use traps around the barn.
- Toenail check and trim.
October 57° / 32°F
- Freezing nights: keep water open and feed extra hay during cold snaps.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
November 44° / 21°F
- Freezing nights: keep water open and feed extra hay during cold snaps.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
- Toenail check and trim.
December 35° / 14°F
- Hard cold: extra hay at night, heated water, windbreaks and coats for crias or seniors; check ears for frostbite.
- Vitamin D for crias and juveniles (ask your vet about product and dose).
Key recommendations
- Shearing: May.
- Best months for crias to be born: May–Aug (breed in Jun–Sep).
- Heat precautions: rarely needed — still provide shade and water.
- Barber pole worm season: Jun — run fecal egg counts every 4–6 weeks in these months.
- Freezing nights: Oct–Apr — keep water from freezing.
- Vitamin D for crias: Oct–Mar.
- Grazing season: May–Sep (about 5 months); feed hay the rest of the year.
- Meningeal worm: Meningeal worm is not established in this region.
- Selenium: Most forage here supplies adequate selenium, and some western areas have high-selenium plants — avoid stacking selenium supplements.
Tools: heat-stress calculator · winter hay calculator · due-date calculator · parasite control guide.
Alpaca farms & shops nearby
No alpaca farms near Fergus County, Montana are mapped on OpenStreetMap yet. If you keep alpacas here, consider adding your farm to OpenStreetMap — it will appear on this page after the next update.
Frequently asked questions
Can you raise alpacas in Fergus County, Montana?
Yes. Alpacas are kept successfully in most climates with good management. Fergus County, Montana scores 89/100 (excellent) on our alpaca climate comfort scale; the key issues are hard winters.
When should alpacas be shorn in Fergus County, Montana?
Plan shearing for May, once nights stay above about 38°F (3°C) but before summer heat builds.
What is the best time for crias to be born in Fergus County, Montana?
Mild months suit newborn crias best — here that is May–Aug. For births then, breed females in Jun–Sep (gestation is about 335 days).
How much hay does an alpaca need per year in Fergus County, Montana?
With roughly 7 months of little or no grazing, plan on about 833 lb (378 kg) — around 17 small square bales — per adult alpaca per year, plus waste.
Nearby counties
Coordinates 47.222, -109.233 · land area 4,339 sq mi. Long-term averages, not forecasts. See methodology and data sources. Back to Montana.