Charlestown, Maryland Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Charlestown weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Rain25%0.31″101°77°—
- SundayJul 5Showers59%0.30″93°76°-8°
- MondayJul 6Light Showers85%0.03″80°72°-13°
- TuesdayJul 7Thunderstorm85%—85°68°+5°
- WednesdayJul 8Drizzle27%—79°66°-6°
- ThursdayJul 9Overcast14%—90°67°+11°
- FridayJul 10Overcast45%—92°71°+2°
AQI 108 (Unhealthy for Sensitive Groups), driven by Ozone. AQI up 54 in the last 6 hours — air quality is degrading. Ozone at AQI 75. Overcast through the UV peak window (cloud cover ~98%) — afternoon ozone should stay flat.
CAUTION Sensitive groups (children, elderly, respiratory conditions) should limit prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 75. Overcast through the UV peak window (cloud cover ~98%) — afternoon ozone should stay flat.
- Present
- AQI 75
- UV peak
- 0.3 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 9
PM × Wind × Precip
PM scrubbed by 2 hours of recent rain — PM2.5 down to 7.7 µg/m³, PM10 to 7.9 µg/m³.
- PM2.5/PM10
- 0.97
- Wind
- light
- Recent rain
- 2h in last 6h
- Pattern
- washed out
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
- 10:56 PM
- Moonset
- 10:08 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Charlestown at a glance
- Today vs. normal: 25°F above the seasonal normal for this latitude
- Last frost: April 13 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 21914
16-Day Forecast — Charlestown
- Sat101°77°25%
- Sun93°76°59%
- Mon80°72°85%
- Tue85°68°85%
- Wed79°66°27%
- Thu90°67°14%
- Fri92°71°45%
- Sat90°71°36%
- Sun83°66°28%
- Mon79°67°22%
- Tue87°66°16%
- Wed90°64°39%
- Thu91°68°36%
- Fri93°71°36%
- Sat95°70°31%
- Sun91°72°49%
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 — Charlestown
SPC has placed Charlestown in the Enhanced Risk category for severe thunderstorms today.
- TODAYENHEnhanced Risk
- TOMORROWSLGTSlight Risk
- DAY 3TSTMGeneral Thunderstorms
Numerous severe storms likely. Tornadoes, large hail, and damaging wind gusts possible across the area. Track NWS warnings if storms develop.
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 Charlestown
- 21901
- 21914