Jefferson, Maryland Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Jefferson weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Overcast32%—99°76°—
- SundayJul 5Showers52%0.18″95°75°-4°
- MondayJul 6Thunderstorm84%0.04″80°70°-15°
- TuesdayJul 7Heavy Showers84%3.2″86°65°+6°
- WednesdayJul 8Light Drizzle33%0.03″78°65°-8°
- ThursdayJul 9Overcast12%—91°65°+13°
- FridayJul 10Overcast41%—87°67°-4°
AQI 81 (Moderate), driven by PM2.5. AQI up 29 in the last 6 hours — air quality is degrading. PM2.5 at 9.3 µg/m³, PM10 at 9.8 µg/m³ — typical background levels with no transport signature.
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 49. Overcast through the UV peak window (cloud cover ~100%) — afternoon ozone should stay flat.
- Present
- AQI 49
- UV peak
- 0.4 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 6
PM × Wind × Precip
PM2.5 at 9.3 µg/m³, PM10 at 9.8 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.95
- Wind
- breezy
- 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).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:02 PM
- Moonset
- 10:14 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Jefferson at a glance
- Today vs. normal: 16°F above the seasonal normal for this latitude
- Last frost: April 12 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 21755
16-Day Forecast — Jefferson
- Sat99°76°32%
- Sun95°75°52%
- Mon80°70°84%
- Tue86°65°84%
- Wed78°65°33%
- Thu91°65°12%
- Fri87°67°41%
- Sat88°67°31%
- Sun78°63°24%
- Mon80°65°17%
- Tue84°60°17%
- Wed86°62°40%
- Thu92°67°42%
- Fri84°68°38%
- Sat92°69°34%
- Sun89°69°44%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 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 — Jefferson
SPC has placed Jefferson in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWSLGTSlight Risk
- DAY 3TSTMGeneral Thunderstorms
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.
ZIP codes in Jefferson
- 21755