Climate Comfort Score
72/100
Good
2026 data Public-data reference. official source
Washington DC Dulles, VA Climate
Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →
30-year climate normals from 1 weather station (1991-2020).
Washington DC Dulles, Virginia has an average annual temperature of 56°F and a climate comfort score of 72/100 (Good). Annual precipitation totals 43.2", including 21.0" of snow. Based on NOAA 30-year normals (1991–2020).
Avg Temperature
56°F (13°C)
Avg High
66°F
Avg Low
45°F
Annual Precip
43.2"
Annual Snow
21.0"
Comfort Score
72/100
Good
Avg Annual Temperature
56°F
30-year mean (NOAA NCEI)
Annual Precipitation
43.2"
Plus 21.0" of snow
Comfort score vs national 100-point ceiling (Washington DC Dulles) 72.0%
National median (≈55)
PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Washington DC Dulles area.
Warming context for Washington DC Dulles
MethodologyHow the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Washington DC Dulles captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 43°F (6°C) | 25°F (-4°C) | 34°F (1°C) | 2.9" | 6.9" | 24.3 | 0.0 |
| February | 46°F (8°C) | 27°F (-3°C) | 36°F (2°C) | 2.6" | 7.0" | 21.1 | 0.0 |
| March | 55°F (13°C) | 34°F (1°C) | 44°F (7°C) | 3.5" | 3.9" | 15.2 | 0.0 |
| April | 67°F (19°C) | 43°F (6°C) | 55°F (13°C) | 3.5" | 0.1" | 3.7 | 0.4 |
| May | 75°F (24°C) | 53°F (12°C) | 64°F (18°C) | 4.7" | 0.0" | 0.2 | 1.4 |
| June | 83°F (28°C) | 62°F (17°C) | 73°F (23°C) | 4.3" | 0.0" | 0.0 | 5.7 |
| July | 88°F (31°C) | 67°F (19°C) | 77°F (25°C) | 4.2" | 0.0" | 0.0 | 12.5 |
| August | 86°F (30°C) | 65°F (18°C) | 76°F (24°C) | 3.5" | 0.0" | 0.0 | 9.3 |
| September | 79°F (26°C) | 58°F (14°C) | 69°F (20°C) | 3.9" | 0.0" | 0.0 | 3.1 |
| October | 68°F (20°C) | 45°F (7°C) | 57°F (14°C) | 3.6" | 0.0" | 2.4 | 0.2 |
| November | 57°F (14°C) | 36°F (2°C) | 46°F (8°C) | 3.1" | 0.3" | 12.9 | 0.0 |
| December | 47°F (8°C) | 29°F (-2°C) | 38°F (3°C) | 3.3" | 2.8" | 21.8 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 2.9"
Snow: 6.9"
10.3 days with precipitation
February 2.6"
Snow: 7.0"
9.1 days with precipitation
March 3.5"
Snow: 3.9"
11.0 days with precipitation
April 3.5"
Snow: 0.1"
11.0 days with precipitation
May 4.7"
12.7 days with precipitation
June 4.3"
10.8 days with precipitation
July 4.2"
11.0 days with precipitation
August 3.5"
9.3 days with precipitation
September 3.9"
9.0 days with precipitation
October 3.6"
8.1 days with precipitation
November 3.1"
Snow: 0.3"
8.6 days with precipitation
December 3.3"
Snow: 2.8"
10.2 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
October 24
50% probability date
Last Spring Freeze
April 15
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,604
Higher = more heating needed
Cooling Degree Days
1,233
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 61% | 7.6 | 20% | 36% |
| February | 60% | 8.7 | 18% | 39% |
| March | 57% | 8.6 | 18% | 36% |
| April | 62% | 7.4 | -401% | -385% |
| May | 69% | 6.4 | -4991% | -4985% |
| June | 69% | 5.8 | -3740% | -3736% |
| July | 70% | 5.6 | -2904% | -2899% |
| August | 71% | 5.6 | 19% | 23% |
| September | 73% | 6.0 | 24% | 27% |
| October | 67% | 6.6 | 25% | 30% |
| November | 66% | 7.0 | -814% | -802% |
| December | 65% | 7.4 | 19% | 37% |
Related Data
PlainEnviro
EPA environmental data — pollution, water quality, and environmental health by location
PlainCarbon
Carbon emissions data — greenhouse gas reporting and facility-level CO2 data
PlainHazard
Natural disaster data — weather-related hazards, FEMA declarations, and risk profiles
PlainAirData
EPA air quality data — AQI readings, pollutant levels, and air quality trends
Climate Guides
Climate Insight: Washington DC Dulles, VA
The NOAA 1991–2020 climate normals describe Washington DC Dulles, Virginia as a location with an annual average temperature of 56°F, ranging from a mean daily high of 66°F to a mean daily low of 45°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USW00093738, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.
Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Washington DC Dulles receives roughly 43.2 inches of precipitation each year, with 21.0 inches typically falling as snow. Growing-season length varies with elevation and microclimate, with the last spring freeze near April 15 and the first fall freeze near October 24. For energy use, 4,604 heating degree days and 1,233 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Washington DC Dulles scores 72/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows — shoulder seasons for mild highs and lows, peak summer for July-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.
Frequently Asked Questions
What is the average temperature in Washington DC Dulles, VA? ▼
The average annual temperature in Washington DC Dulles, Virginia is 56°F. The warmest month averages 88°F (31°C) and the coldest averages 25°F (-4°C).
How much rain does Washington DC Dulles get? ▼
Washington DC Dulles receives 43.2 inches of precipitation annually, including 21.0 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Washington DC Dulles? ▼
Washington DC Dulles has a climate comfort score of 72/100 (Good). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Washington DC Dulles? ▼
Growing season data is not available for Washington DC Dulles.
How much energy does heating and cooling require in Washington DC Dulles? ▼
Washington DC Dulles has 4,604 heating degree days and 1,233 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Washington DC Dulles climate data come from? ▼
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from weather station USW00093738. These 30-year averages are the standard reference for typical weather conditions.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USW00093738. For informational purposes only.
Read our methodology — how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
