Frederick, Maryland Weather
Day 93 of summer. Read today’s microseason across nine climate regions →
Frederick weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 10:23 AM EDT · Open-Meteo
- TodaySep 21Drizzle later40%0.04″72°64°—
- TuesdaySep 22Rain71%0.74″64°58°-8°
- WednesdaySep 23Light Drizzle71%0.12″64°50°0°
- ThursdaySep 24Overcast23%—66°46°+2°
- FridaySep 25Clear12%—70°46°+4°
- SaturdaySep 26Clear12%—73°47°+3°
- SundaySep 27Overcast——75°49°+2°
Air quality now AQI 25 · Good
AQI 25 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 5.0 µg/m³, PM10 at 5.1 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 during the projected peak around 7 PM.
What's driving it
PM × Wind × Precip
PM2.5 at 5.0 µg/m³, PM10 at 5.1 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.98
- 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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:40 PM
- Moonset
- 1:30 AM
- In sign
- ♑︎ Capricorn
Frederick at a glance
- Today vs. normal: Today averages 68°F (high 72°F, low 64°F), about the 67°F normal for Sep 21
- Last frost: April 2 (1991–2020 median, NOAA station 3 km away)
- Microseason: Sep 21–25
- Planting calendar: September — harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Frederick
- Mon72°64°40%
- Tue64°58°71%
- Wed64°50°71%
- Thu66°46°23%
- Fri70°46°12%
- Sat73°47°12%
- Sun75°49°6%
- Mon77°54°5%
- Tue78°56°8%
- Wed79°57°20%
- Thu81°58°16%
- Fri76°56°18%
- Sat79°54°23%
- Sun74°58°17%
- Mon72°51°23%
- Tue63°43°19%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Frederick
Interactive wind and temperature map centered on Frederick — it loads in your browser. Open the full weather map.
Right now in the garden
Late season
As of September 21, the first frost (around November 6) is about 7 weeks away. Frost-tender plants keep producing until then. This city's planting calendar for September: harvest tomatoes, peppers, beans, summer squash, and winter squash.
SPC Convective Outlook
Storm Prediction Center — Frederick
SPC includes Frederick in the general thunderstorm area today — no severe risk, but storms are possible.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWNONENo severe risk
- DAY 3NONENo severe risk
Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook.
Sun & seasons in Frederick
Frederick sits in Frederick County, where the year’s longest day runs 14h 57m of daylight and its shortest just 9h 23m — a swing of +5h 34m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Baltimore, the state’s largest city, lies about 44 miles to the ESE. The nearest town Frederick tracks is Keedysville, roughly 16 miles to the WNW.
Air quality in Frederick
Air quality in Frederick’s county has trended dirtier since 2020; its cleanest year on record was 2020 (median AQI 40). See the full air-quality history for Frederick.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes | lettuce, spinach, radishes |
| May | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | beans, squash | lettuce, peas, spinach, beans, summer squash, garlic |
| July | tomatoes, peppers, beans, squash | tomatoes, peppers, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| September | — | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
The year in Frederick tops out in July (~79°F) and dips lowest in January (~35°F), with September wettest at 5.8 inches and January driest at 2.6 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 35° | 2.6″ | 6 |
| February | 38° | 3.0″ | 5 |
| March | 46° | 3.7″ | 9 |
| April | 57° | 3.5″ | 7 |
| May | 66° | 4.0″ | 7 |
| June | 74° | 4.3″ | 7 |
| July | 79° | 3.9″ | 7 |
| August | 77° | 2.9″ | 5 |
| September | 70° | 5.8″ | 7 |
| October | 58° | 3.3″ | 4 |
| November | 47° | 2.7″ | 5 |
| December | 39° | 4.0″ | 7 |
Regional context
Similar climates Ballenger Creek, MD, Spring Ridge, MD, Bartonsville, MD
By the nearest station's NOAA NCEI 1991-2020 normals, Frederick sees 35°F Januarys and 79°F Julys, a 44°F range, plus around 43.5 inches of precipitation across 76 days.
Rainfall in Frederick splits evenly between the seasons: September tops out at 5.8 inches over 7.3 rainy days, and January logs 2.6 inches across 5.8 — neither half of Frederick's year dominates. It is a balanced pattern Frederick shares with places like Ballenger Creek, MD, Spring Ridge, MD and Bartonsville, MD.
By April 2 the frosts ease in Frederick, opening the season for peas, lettuce, spinach, and radishes. Warm-soil crops in Frederick wait about two weeks past Frederick's last frost, once the soil warms. Around November 6, freezing nights resume in Frederick and tender crops must come in. Sheltered Frederick yards can escape a light frost.
Similar climates: Ballenger Creek, MD, Spring Ridge, MD, Bartonsville, MD, Walkersville, MD, Braddock Heights, MD.
Frequently asked
- When does it freeze in Frederick?
- In Frederick, expect the last spring frost near April 2; Frederick's first autumn frost comes around November 6.
- What is the rainy season in Frederick?
- Frederick sees its heaviest rain in September (around 5.8 inches), part of roughly 44 inches a year.
- What is the warmest month in Frederick?
- The warmest stretch in Frederick comes in July, around 79°F on average.
- What is the coldest month in Frederick?
- On average January is the chilliest month in Frederick, about 35°F.
- When can I start a vegetable garden in Frederick?
- Frost-hardy sowings begin at April 2 in Frederick; warm-season starts follow two weeks on.
- How many rainy days does Frederick get?
- Frederick averages about 76 days with measurable rain or snow each year.
- What hardiness zone is Frederick?
- Frederick sits in the USDA zone set by January lows near 35°F; the USDA ZIP tool gives the band.
- What is the 10-day forecast for Frederick?
- Frederick'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 Frederick?
- See this week's day-by-day rain chances for Frederick in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Frederick?
- Current conditions for Frederick and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Frederick forecast updated?
- The Frederick forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Frederick?
- Today's sunrise and sunset times for Frederick 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 Frederick?
- The next few days in Frederick's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Frederick sits at 39.4°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in Frederick
- 21701
- 21702
- 21703
- 21704
- 21705
- 21709