Local alpaca guide · Montana

Raising Alpacas in Carter County, Montana

Carter County, Montana has a cold semi-arid climate (Köppen BSk): summer highs average 86°F in July and winter lows average 9°F in January, with about 16 inches of precipitation a year. The main challenges for alpaca keepers here are hard winters.

Climate snapshot for alpacas

86/100Alpaca climate comfort score
86°FAverage high, Jul
9°FAverage low, Jan
~13Days above 90°F (32°C) per year
~190Frost nights per year
16 inAnnual precipitation
3Barber 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
  • Low meningeal worm risk

Overall rating: 86/100 — Excellent on our alpaca climate comfort score. Climate type: Cold semi-arid (Köppen BSk).

Month-by-month climate

Average highAverage lowPrecipitation
0°0.022°1.045°2.068°3.090°4.0Jan: 0.4 inJanFeb: 0.5 inFebMar: 0.8 inMarApr: 1.7 inAprMay: 2.9 inMayJun: 2.8 inJunJul: 2.0 inJulAug: 1.5 inAugSep: 1.3 inSepOct: 1.4 inOctNov: 0.5 inNovDec: 0.4 inDecJan high: 31°FFeb high: 34°FMar high: 46°FApr high: 56°FMay high: 66°FJun high: 76°FJul high: 86°FAug high: 84°FSep high: 74°FOct high: 58°FNov high: 44°FDec high: 33°FJan low: 9°FFeb low: 11°FMar low: 21°FApr low: 30°FMay low: 40°FJun low: 50°FJul low: 56°FAug low: 54°FSep low: 43°FOct low: 31°FNov low: 20°FDec low: 11°F°Fin
MonthHighLowPrecip.Heat-stress indexNotes
Jan31°F9°F0.4 in91 · okfrost
Feb34°F11°F0.5 in102 · okfrost
Mar46°F21°F0.8 in107 · okfrost
Apr56°F30°F1.7 in107 · okfrost
May66°F40°F2.9 in122 · okworms, grass
Jun76°F50°F2.8 in128 · cautionworms, grass
Jul86°F56°F2.0 in127 · cautionworms, grass
Aug84°F54°F1.5 in132 · cautiongrass
Sep74°F43°F1.3 in121 · okgrass
Oct58°F31°F1.4 in101 · okfrost
Nov44°F20°F0.5 in104 · okfrost
Dec33°F11°F0.4 in88 · okfrost

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 Carter County, Montana

January 31° / 9°F

Hard coldVitamin D
  • 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 34° / 11°F

Hard coldVitamin D
  • 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° / 21°F

FrostVitamin D
  • 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 56° / 30°F

Frost
  • Run pre-season fecal egg counts so you know each animal's baseline.
  • 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 66° / 40°F

ShearingWorm seasonCria season
  • Shearing month: shear the whole herd, and trim toenails, check teeth and body condition while animals are restrained.
  • 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.
  • Spring grass: switch from hay to pasture gradually over 1–2 weeks and monitor body condition.
  • Toenail check and trim.

June 76° / 50°F

Worm seasonCria seasonBreeding
  • Warm spells possible — watch for open-mouth breathing in heavy-fleeced or dark animals.
  • 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 86° / 56°F

Worm seasonCria seasonBreeding
  • Warm spells possible — watch for open-mouth breathing in heavy-fleeced or dark animals.
  • 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).
  • Toenail check and trim.

August 84° / 54°F

Cria seasonBreeding
  • 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 74° / 43°F

Breeding
  • 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 58° / 31°F

FrostVitamin D
  • 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° / 20°F

FrostVitamin D
  • 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 33° / 11°F

Hard coldVitamin D
  • 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: May–Jul — 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 Carter 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 Carter County, Montana?
Yes. Alpacas are kept successfully in most climates with good management. Carter County, Montana scores 86/100 (excellent) on our alpaca climate comfort scale; the key issues are hard winters.
When should alpacas be shorn in Carter 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 Carter 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 Carter 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 45.517, -104.515 · land area 3,340 sq mi. Long-term averages, not forecasts. See methodology and data sources. Back to Montana.