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Charlo, Montana Weather

Summer heat breaks with monsoon. Day 43 of summer. Read this microseason across nine climate regions →

Charlo weather forecast — hour by hour, 7-day outlook, NOAA radar

Charlo, MT
Sunday, August 2 at 8:59 AM
63
°
Clear
Feels like
57°
Humidity
32%
Wind
6 mph
Sunrise
12:16 AM
Sunset
3:09 PM
Charlo, MT
Hour by hour · 24h
24-Hour ForecastCharlo, MT: 24-hour forecast. Temperatures range from 53 to 74 degrees Fahrenheit.
L 53°H 74°
Charlo, MT
7-day forecast
  1. Today
    Aug 2
    Clear
    74°59°
  2. Monday
    Aug 3
    Overcast
    74°53°
  3. Tuesday
    Aug 4
    Overcast
    81°50°+7°
  4. Wednesday
    Aug 5
    Overcast
    89°53°+8°
  5. Thursday
    Aug 6
    Clear
    98°58°+9°
  6. Friday
    Aug 7
    Overcast
    100°63°+2°
  7. Saturday
    Aug 8
    Clear
    93°61°-7°
Charlo, MT
Anemometer · 24h winds · from true
NESW
From · True
WNW
294° · backing 85°
Direction
WNW
294°
Sustained
6
mph
Gust
13
mph
Peak 24h
26
avg 7 mph
Beaufort · 2 · LIGHT BRZ
0
CALM
<1
1
LIGHT AIR
1–3
2
LIGHT BRZ
4–7
3
GENTLE BRZ
8–12
4
MOD BRZ
13–18
5
FRESH BRZ
19–24
6
STRONG BRZ
25–31
7
NEAR GALE
32–38
24h · sust vs gust · mph
avg 7 mph · pk 26 mph @ 11:00p
01020MPHB1B2B3B4B5-21h-18h-15h-12h-9h-6h-3h-24hNOWpk 204SUSTGUST
−24h−18h−12h−6hnow
Light breeze backing 85° from the wnw.
Charlo, MT
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
914.7
+1.3 mb in 3h · rising · 27.01 inHg
Now
914.7
mb
3h
+1.3
mb
12h
+4.3
mb
24h
+5.6
mb
Regime · STORM
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 909915
900905910915920-21h-18h-15h-12h-9h-6h-3h-24hNOW914.4908.8914.4
The low is filling — pressure climbing out of storm territory.
Charlo, MT
Air quality
56
AQI
Moderate
-5 in 6h

AQI 56 (Moderate), driven by Ozone. AQI down 5 over the last 6 hours (gradual decline). Ozone at AQI 34 now. With UV 2.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 11.

OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.

PM 2.5Good
1.9μg/m³
PM 10Good
2μg/m³
NO₂Good
1μg/m³
OzoneDRIVERModerate
72μg/m³
UV IndexLow
0.7

What's driving it

Ozone × UV × Sky

Ozone at AQI 34 now. With UV 2.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 11.

Present
AQI 34
UV peak
2.3 at 1 PM
Sky at peak
clear
Projected peak
AQI 11
Charlo, MT
Sky cover · visibility · 24h
Cloud cover
0%
CLEAR
100%0%−24h−18h−12h−6hnow

Visibility
51.6mi
UNLIMITED
156 mi0 mi−24h−18h−12h−6hnow
Earth · GOES-19 ABI
Full Disk · Visible · GeoColor
GOES-19 full disk Visible · GeoColor
True-color daytime, blue/IR sandwich at night
14:59 UTC · Charlo, MT · NOAA NESDIS / STAR · up to 10848 px
Continental US · GOES-19 ABI
CONUS Sector · Visible · GeoColor
GOES-19 CONUS Visible · GeoColor
Daytime true-color, blue-light/IR sandwich at night
14:59 UTC · Charlo, MT · NOAA NESDIS / STAR · 5-min cadence · up to 10000 px
Charlo, MT
Satellite · infrared · animated
Charlo, MT
Loading IR frames…
IR · cloud-top temp© RainViewer · Carto
Charlo, MT
Almanac · Sunday, August 2
Red sky at night, sailor's delight.
Civil dawn
5:41 AM
Sunrise
12:16 AM
Daylight
14h 53m
Sunset
3:09 PM
Civil dusk
9:46 PM
Planting note
Sow fall peas. Start kale and collard seedlings for fall.
Charlo, MT
The moon
Waning Gibbous
84% illuminated
Moonrise
10:23 PM
Moonset
10:48 AM
In sign
♓︎ Pisces
Charlo, MT
Microseason
Aug 1–5

Summer heat breaks with monsoon

plant
Jan 159% of the yearDec 31

Read this microseason across nine climate regions →

Charlo at a glance

  • Today vs. normal: 8°F above the seasonal normal for this latitude
  • Last frost: May 31 (climatological average for this latitude)
  • Microseason: Aug 1–5
  • Planting window: Sow fall peas. Start kale and collard seedlings for fall.

ZIP code: 59824

16-Day Forecast — Charlo

  1. Sun74°59°1%
  2. Mon74°53°6%
  3. Tue81°50°0%
  4. Wed89°53°0%
  5. Thu98°58°0%
  6. Fri100°63°0%
  7. Sat93°61°0%
  8. Sun93°58°2%
  9. Mon92°57°5%
  10. Tue88°51°8%
  11. Wed88°53°8%
  12. Thu81°55°3%
  13. Fri86°53°13%
  14. Sat92°58°13%
  15. Sun94°60°12%
  16. Mon90°60°14%

Forecast data from Open-Meteo (CC BY 4.0).

Right now in the garden

Peak growing season

As of August 2, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.

Sun & seasons in Charlo

Charlo sits in Lake County, where the year’s longest day runs 15h 58m of daylight and its shortest just 8h 27m — a swing of +7h 31m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.

Billings, the state’s largest city, lies about 290 miles to the ESE. The nearest town Charlo tracks is Bull Lake, roughly 95 miles to the NW.

Air quality in Charlo’s county has trended dirtier since 2020; its cleanest year on record was 2020 (median AQI 7). See the full air-quality history for Charlo.

January 1–5: Deep freeze grips the high peaks.January 6–10: Ice thickens on alpine tarns.January 11–15: Springs stir beneath locked earth.January 16–20: Grouse call from the transition zone.January 21–25: First signals of the soil's turning.January 26–31: Stream water crystallizes thick.February 1–5: The year's coldest fortnight begins.February 6–10: East wind carries a subtle promise.February 11–15: Snowmelt springs whisper beneath ice.February 16–20: Red-wing calls rise from the wetlands.February 21–25: Rain begins to trace the snowline upward.February 26–28: Mist gathers in the warming canyons.March 1–5: Grass and trees stir from their sleep.March 6–10: Hibernators break through frozen ground.March 11–15: First blooms open to the spring sun.March 16–20: Mountain bluebirds return to the summits.March 21–25: Spring equinox at the divide.March 26–31: Aspen catkins burst in clusters.April 1–5: Thunderstorms rumble over granite peaks.April 6–10: Swallows and swifts slice the warming sky.April 11–15: Sandhill cranes call through the wetlands.April 16–20: Rainbows arch over the snowfields.April 21–25: New growth explodes across the montane.April 26–30: Last frost yields to summer growth.May 1–5: Wildflowers crest the high meadows.May 6–10: Summer monsoon clouds gather southward.May 11–15: Snowmelt crests toward the divide.May 16–20: High country wildflowers peak.May 21–25: Summer heat accelerates the growing season.May 26–31: Summer settles into the high country.June 1–5: Pikas hayfeeding in granite peaks.June 6–10: Glacier lily carpets the snowmelt.June 11–15: Paintbrush crowns the ridges.June 16–20: Thunderheads build by noon.June 21–25: Long light holds the peaks.June 26–30: Monsoon moisture drifts north.July 1–5: Monsoon storms drench the south.July 6–10: Wind builds through canyons.July 11–15: Lightning crowns every peak.July 16–20: Elk herds claim alpine meadows.July 21–25: Pika caches reach their peak.July 26–31: Monsoon pulses weaken northward.August 1–5: Summer heat breaks with monsoon.August 6–10: First frost creeps to peaks.August 11–15: Cool wind returns from north.August 16–20: Monsoon clouds gather over the peaks.August 21–25: The monsoon breaks into scattered showers.August 26–31: Summer insects thin as autumn wind rises.September 1–5: Elk descend from summer high meadows.September 6–10: Dew crystallizes on high grass at dawn.September 11–15: Hawks begin the long crossing southward.September 16–20: Equinox: darkness claims the high passes.September 21–25: Thunder retreats as the monsoon dies.September 26–30: First frost hardens the high valleys.October 1–5: October: the aspen stands reach their peak.October 6–10: Aspen gold slides downslope with the chill.October 11–15: Snow settles on the high passes.October 16–20: Elk bugling fades as rut nears its end.October 21–25: First hard frost grips the basin.October 26–31: Late rains settle into November patterns.November 1–5: Aspen canopy falls to earth.November 6–10: Granite bones emerge from cover.November 11–15: Earth begins to harden.November 16–20: Bare ranges hold silence.November 21–25: Snow returns to the peaks.November 26–30: North wind strips the landscape.December 1–5: Deep darkness settles over the ranges.December 6–10: Winter locks the high country.December 11–15: Elk withdraw to winter range.December 16–20: Ice thickens across frozen water.December 21–25: Winter solstice — the sun returns.December 26–31: The year closes in silence.🌱February 14 — First skunk-cabbage spathes thaw their way up☀️March 20 — Spring equinox — day and night balance🌸April 5 — Cherry blossoms peak in the parks🐦May 10 — Warbler migration peaks along the coastMay 25 — First fireflies scout the meadows at dusk🌞June 21 — Summer solstice — longest day🦗July 25 — Peak cicada chorus in the afternoons🌊August 18 — Warmest sea-surface temperatures of the year🍂September 22 — Autumn equinox — the slow turn❄️October 25 — First widespread frost in the suburbs🍁November 10 — Peak leaf color across the Hudson Valley🌙December 21 — Winter solstice — longest night

Microseason · August 1–5

Summer heat breaks with monsoon

Late summer monsoon surge; southern reaches drench under Gulf moisture; northern peaks cool rapidly as monsoon remnants push north.

Day 214 of 365 · Wedge 43 of 72

The solar year drawn as a wheel of 72 five-day windows. Each wedge is one microseason; the four colored arcs mark winter, spring, summer, and autumn; the small icons sit at notable phenological events. The crimson pointer creeps clockwise as the year turns.

Planting calendar

MonthPlantHarvest
January
February
March
April
Maylettuce, peas, spinach, radisheslettuce, peas, radishes
Junelettuce, peas, spinach, radishes, tomatoes, peppers, beans, squashlettuce, peas, radishes
Julytomatoes, peppers, beans, squashtomatoes, beans, summer squash
Augusttomatoes, peppers, beans, squash, fall brassicas, garlic (overwinter), carrotstomatoes, beans, summer squash
Septemberfall brassicas, garlic (overwinter), carrotstomatoes, beans, summer squash
Octoberwinter squash, tomatoes (last)
November
December

A year in weather

Charlo peaks at about 69°F in July and bottoms near 30°F in December; June brings the heaviest rain (2.6 inches) and December the least (0.9 inches).

MonthMean tempPrecipRainy days
January30°0.93
February31°1.13
March39°0.93
April47°1.84
May55°2.37
June61°2.67
July69°1.03
August68°1.23
September59°1.53
October47°1.34
November36°1.13
December30°0.93

Regional context

By the nearest station's NOAA NCEI 1991-2020 normals, Charlo sees 30°F Januarys and 69°F Julys, a 39°F range, plus around 16.7 inches of precipitation across 46 days.

Summer convection drives Charlo's precipitation: June logs 2.6 inches on 6.8 rainy days, against December's 0.9 inches on 2.6 — warm-season storms carry Charlo's moisture. That puts Charlo in a summer-convective cohort with places like Kicking Horse, MT, Ronan, MT and St. Ignatius, MT.

Charlo's growing window opens around late-May, once Charlo's overnight lows stop freezing — sow kale, peas, spinach, and parsnips. In Charlo, warm-season transplants — tomatoes, peppers, basil — wait two weeks past Charlo's frost date. Charlo's window closes around early-October as overnight lows return below freezing. In Charlo, low spots run 4-7°F colder than nearby slopes, nudging Charlo's frost dates a week.

Similar climates: Kicking Horse, MT, Ronan, MT, St. Ignatius, MT, Old Agency, MT, Ravalli, MT.

Frequently asked

When does it freeze in Charlo?
Frost typically leaves Charlo by mid-May and returns to Charlo near mid-October.
What is the rainy season in Charlo?
Rainfall in Charlo peaks in June near 2.6 inches, out of about 17 inches annually.
What is the warmest month in Charlo?
The warmest stretch in Charlo comes in July, around 69°F on average.
What is the coldest month in Charlo?
On average December is the chilliest month in Charlo, about 30°F.
When can I start a vegetable garden in Charlo?
Frost-hardy sowings begin at mid-May in Charlo; warm-season starts follow two weeks on.
How many rainy days does Charlo get?
Charlo averages about 46 days with measurable rain or snow each year.
What hardiness zone is Charlo?
Charlo's hardiness zone tracks its winter low; with December near 30°F, check the USDA ZIP map for the exact zone.
What is the 10-day forecast for Charlo?
Charlo's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
Will it rain this week in Charlo?
See this week's day-by-day rain chances for Charlo in the daily forecast above, and the next 24 hours in the hourly chart.
What is the weather like right now in Charlo?
Current conditions for Charlo and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
How often is the Charlo forecast updated?
The Charlo forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
When are sunrise and sunset in Charlo?
Today's sunrise and sunset times for Charlo are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
How accurate is the weather forecast for Charlo?
The next few days in Charlo's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.

Climate

Charlo's cold semi-arid climate in Montana pairs 30°F Januarys with 69°F Julys, 39°F apart across the seasons.

Charlo sees close to 17 inches of precipitation annually, falling across some 46 wet days.

The 39°F gap between Charlo's summer and winter, at 47.4°N, shapes Charlo's frost calendar.

ZIP codes in Charlo

  • 59824

Climate normals from the Open-Meteo Climate API. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.