Waltham, Minnesota Weather
Prairie lightning bugs rise. Day 77 of spring. Read this microseason across nine climate regions →
Waltham weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast38%—79°64°—
- FridayJun 5Foggy16%—83°63°+4°
- SaturdayJun 6Overcast17%—82°59°-1°
- SundayJun 7Light Showers38%—82°65°0°
- MondayJun 8Showers64%0.24″77°66°-5°
- TuesdayJun 9Showers49%0.25″76°67°-1°
- WednesdayJun 10Thunderstorm13%—90°66°+14°
Ozone at AQI 44 — peak already passed at 1 PM under overcast skies. AQI up 9 over the last 6 hours (gradual rise). Levels should ease through evening.
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 44 — peak already passed at 1 PM under overcast skies. Levels should ease through evening.
- Present
- AQI 44
- UV peak
- 0.6 at earlier today
- Sky at peak
- overcast
- Projected peak
- AQI 44
PM × Wind × Precip
PM2.5 at 7.5 µg/m³, PM10 at 8.0 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.94
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- background
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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 4:54 AM
- Moonset
- 2:02 PM
- In sign
- ♒︎ Aquarius
Prairie lightning bugs rise
Waltham at a glance
- Today vs. normal: 7°F above the seasonal normal for this latitude
- Last frost: May 9 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 4, 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 — Waltham
SPC has placed Waltham in the Slight Risk category for severe thunderstorms tomorrow.
- TODAYMRGLMarginal Risk
- TOMORROWSLGTSlight Risk
- DAY 3NONENo severe risk
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
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.