Roy, Montana Weather
Monsoon storms drench the south. Day 15 of summer. Read this microseason across nine climate regions →
Roy weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Overcast——89°57°—
- SundayJul 5Light Drizzle38%0.03″86°65°-3°
- MondayJul 6Drizzle44%—78°57°-8°
- TuesdayJul 7Light Showers68%—70°60°-8°
- WednesdayJul 8Showers39%0.28″91°59°+21°
- ThursdayJul 9Overcast39%—77°59°-14°
- FridayJul 10Clear——84°57°+7°
AQI 44 (Good), driven by Ozone. AQI up 6 over the last 6 hours (gradual rise). Ozone at AQI 34 now. With UV 0.0 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 8 around 1 PM.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 34 now. With UV 0.0 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 8 around 1 PM.
- Present
- AQI 34
- UV peak
- 0.0 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 8
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:41 PM
- Moonset
- 11:29 AM
- In sign
- ♓︎ Pisces
Monsoon storms drench the south
Roy at a glance
- Today vs. normal: 12°F above the seasonal normal for this latitude
- Last frost: May 30 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 59471
16-Day Forecast — Roy
- Sat89°57°1%
- Sun86°65°38%
- Mon78°57°44%
- Tue70°60°68%
- Wed91°59°39%
- Thu77°59°39%
- Fri84°57°3%
- Sat100°62°8%
- Sun98°73°9%
- Mon101°70°13%
- Tue105°74°15%
- Wed103°77°26%
- Thu91°70°29%
- Fri95°62°29%
- Sat91°66°16%
- Sun90°64°15%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 5, 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.
SPC Convective Outlook
Storm Prediction Center — Roy
SPC has placed Roy in the Marginal Risk category for severe thunderstorms tomorrow.
- TODAYNONENo severe risk
- TOMORROWMRGLMarginal Risk
- DAY 3TSTMGeneral Thunderstorms
Isolated severe storms possible. Limited threat for hail or damaging wind.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
ZIP codes in Roy
- 59471