Geraldine, Montana climate: Normal weather by month, frost dates and records
Geraldine's normal year runs from 15°F January nights to 86°F July afternoons, with 16.9 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.2°C, January lows of −10°C, July highs of 30°C, 428 mm of precipitation a year.
- NOAA stationGeraldine
- Station IDUSC00243445
- Location47.60°N 110.27°W
- Elevation3,145 ft (959 m)
- Population206
On October 22, the normal high in Geraldine is 57°F and the normal low 31°F, and the chance of measurable rain or snow is 24%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Geraldine.
- Jan 37° 15°
- Feb 40° 16°
- Mar 50° 24°
- Apr 59° 32°
- May 68° 41°
- Jun 76° 49°
- Jul 86° 55°
- Aug 86° 53°
- Sep 75° 45°
- Oct 60° 34°
- Nov 46° 24°
- Dec 39° 16°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Geraldine each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 15°F. The most precipitation falls in June (3.23 in), the least in February (0.57 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 37°F | 15°F | 25.8°F | 0.60 | 9 | <1 | 26 | 8 h 50 min |
| February | 40°F | 16°F | 28.2°F | 0.57 | 7 | <1 | 23 | 10 h 10 min |
| March | 50°F | 24°F | 36.5°F | 0.82 | 8 | <1 | 24 | 11 h 50 min |
| April | 59°F | 32°F | 45.5°F | 2.10 | 10 | <1 | 15 | 13 h 30 min |
| May | 68°F | 41°F | 54.5°F | 2.69 | 11 | 1 | 4 | 15 h 10 min |
| June | 76°F | 49°F | 62.4°F | 3.23 | 14 | 2 | <1 | 16 h |
| July | 86°F | 55°F | 70.6°F | 1.71 | 9 | 13 | <1 | 15 h 40 min |
| August | 86°F | 53°F | 69.4°F | 1.28 | 7 | 13 | <1 | 14 h 20 min |
| September | 75°F | 45°F | 60.1°F | 1.49 | 7 | 3 | 2 | 12 h 40 min |
| October | 60°F | 34°F | 47.1°F | 1.14 | 8 | <1 | 13 | 11 h |
| November | 46°F | 24°F | 35.1°F | 0.63 | 7 | <1 | 22 | 9 h 20 min |
| December | 39°F | 16°F | 27.1°F | 0.59 | 6 | <1 | 26 | 8 h 30 min |
| Year (annual) | 60°F | 34°F | 46.8°F | 16.85 | 104 | 31 | 155 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 3°C | −10°C | −3.4°C | 15 mm |
| February | 5°C | −9°C | −2.1°C | 14 mm |
| March | 10°C | −5°C | 2.5°C | 21 mm |
| April | 15°C | 0°C | 7.5°C | 53 mm |
| May | 20°C | 5°C | 12.5°C | 68 mm |
| June | 24°C | 9°C | 16.9°C | 82 mm |
| July | 30°C | 13°C | 21.4°C | 43 mm |
| August | 30°C | 12°C | 20.8°C | 33 mm |
| September | 24°C | 7°C | 15.6°C | 38 mm |
| October | 16°C | 1°C | 8.4°C | 29 mm |
| November | 8°C | −5°C | 1.7°C | 16 mm |
| December | 4°C | −9°C | −2.7°C | 15 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Fort Benton (24 miles away), gets 38 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00243445; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Geraldine?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (7).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00243445.
When is the last frost in Geraldine?
In Geraldine, the last spring frost (32°F) comes after May 14 in half of years and after May 28 in one year in ten; the first autumn frost comes before September 26 in half of years and before September 13 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 141 year in 10 after May 28; 9 in 10 after May 2
- First autumn frost, half of years before
- September 261 year in 10 before September 13; 9 in 10 before October 7
NOAA puts the median frost-free season at 134 days, and the season without a hard freeze (28°F) at 155 days.
A hard freeze (28°F) comes after May 3 in half of springs and before October 4 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Geraldine in zone 4b in ZIP code 59446, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Geraldine's NOAA station is in zone 4b: the coldest night of a typical year reaches −25°F (17 complete years).
Frost dates for every NOAA station in Montana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00243445; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Geraldine?
In a normal year in Geraldine, 31 days a year reach 90°F (3 of them 100°F or more), 155 nights fall to 32°F or colder and 104 days bring measurable precipitation.
- Days at 90°F or more
- 31a normal year
- Days at 100°F or more
- 3a normal year
- Nights at 32°F or colder
- 155a normal year
- Days that stay below freezing
- 34high of 32°F or less
- Days with 0.01 inch of precipitation
- 104a normal year
The highest temperature in this station's record (since 1950) is 108°F, on August 5, 1961; the lowest is −42°F, on January 24, 1969.
The wettest calendar year on that record is 1993, with 24.20 in; the snowiest season is 1966–67, with 98.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00243445; records: ACIS (NOAA Regional Climate Centers), station USC00243445. Records use complete months only; a month missing more than three days is left out.
How sunny is Geraldine?
Over a year 76% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Geraldine, 4.0 kWh per square metre a day. July is the sunniest month (87%) and December the cloudiest (66%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 71% | 1.5 |
| February | 73% | 2.5 |
| March | 71% | 3.6 |
| April | 69% | 4.8 |
| May | 71% | 5.8 |
| June | 76% | 6.6 |
| July | 87% | 7.2 |
| August | 85% | 5.9 |
| September | 78% | 4.3 |
| October | 72% | 2.7 |
| November | 68% | 1.6 |
| December | 66% | 1.2 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Geraldine need?
A normal year in Geraldine brings 7,051 heating degree days, 31% more than the median U.S. place (5,373), and 467 cooling degree days, 49% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,280 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,215 | 0 |
| February | 1,032 | 0 |
| March | 882 | 0 |
| April | 587 | 1 |
| May | 335 | 9 |
| June | 125 | 47 |
| July | 26 | 198 |
| August | 36 | 172 |
| September | 185 | 38 |
| October | 559 | 3 |
| November | 897 | 0 |
| December | 1,173 | 0 |
| Year (annual) | 7,051 | 467 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00243445. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
How does Geraldine's climate compare?
Geraldine is warmer than 126 of the other 140 places with their own NOAA record in Montana, and wetter than 102. Across the 7,247 U.S. stations with normals, its annual mean of 46.8°F is warmer than 27%.
In the Köppen classification computed from these normals, Geraldine is BSk: cold semi-arid steppe. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Geraldine share this climate record?
Square Butte has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Square Butte, MT24 people · 7 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Geraldine's climate
What is the coldest month in Geraldine?
January, with a normal high of 37°F and a normal low of 15°F. The warmest is July (86°F by day, 55°F at night).
Does it snow in Geraldine?
Yes. NOAA publishes no 1991-2020 snowfall normal for Geraldine's NOAA station; the nearest record that keeps one, Fort Benton (24 miles away), records 38 inches of snow in a normal year.
What is the rainiest month in Geraldine?
June, with 3.23 in of precipitation in a normal year; the driest is February with 0.57 in.
What plant hardiness zone is Geraldine in?
The USDA's 2023 map puts Geraldine in zone 4b in ZIP code 59446, the nearest ZIP area. By the same method at Geraldine's NOAA station, the coldest night of a typical year reaches −25°F (17 years, 1991-2020): zone 4b.
How late can frost come in Geraldine?
In half of years the last 32°F night comes after May 14; in one year in ten it comes after May 28. Waiting until May 28 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Montana climateThe statewide normals and every place in the state
- Shonkin (7 mi S), MT15 miles from this station, 44.1°F a year
- Highwood, MT19 miles from this station, 46.7°F a year
- Fort Benton, MT24 miles from this station, 45.4°F a year
- Denton, MT25 miles from this station, 42.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made