Washington DC Dulles, VA Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Washington DC Dulles's primary NOAA station, WASHINGTON DC DULLES AP.
The climate verdict for Washington DC Dulles
Washington DC Dulles, Virginia has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 56°F. Its climate comfort score of 73/100 (good) lands mid-pack nationally, exceeding 66% of station-mapped location scores.
- 56°F
- annual average temperature (NOAA normal)
- 73/100
- comfort score, above 66% of station-mapped location scores
- 43.2"
- annual precipitation · 21" snow
- 192 days
- frost-free days per growing season
Washington DC Dulles: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USW00093738 · Washington DC Dulles, VA 56°F mean · 43.2" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-MID · SWING-MID · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 56°F
- RANK-UPPER #4,322
- PHOTO-FINISH ≈ S Point
- PRCP-MID 43.2"
- SWING-MID 43°F
- COMF-MID 73/100
- LOAD-HEAT 4,604 HDD
- STN-1 USW00093738
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: S Point, OH (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every VA station list.
- Washington DC D… (this station) 56°F
- Cold Wilmington New…, DE 56°F
- Hot Newark Ag Farm, DE 56°F
- Near S Point, OH 56°F
- Near W Plains, MO 56°F
Climate Living Index · Washington DC Dulles
Washington DC Dulles: 61/100 · grade C
Washington DC Dulles publishes all six Living Index dimensions from NOAA annual/seasonal normals · NOAA daily multivariate normals · NOAA hourly normals.
PlainClimate-derived for Washington DC Dulles, not an official NOAA rating. Rankings still use Comfort Score 73/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 102 calendar days | 75/100 · B |
| Precipitation balance | 43.2 in · 8.2 from 35 in | 71/100 · B |
| Annual temperature balance | 55.7°F · 11.8° from 67.5°F | 62/100 · C |
| Frost-free season | 192 days/year | 59/100 · C |
| Snowfall burden | 21.0 inches/year | 48/100 · D |
| Summer moisture balance | 64.1°F mean dew point | 39/100 · F |
Washington DC Dulles · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Washington DC Dulles is a temperate Köppen climate: Cfa
Coldest-month mean 33.9°F and warmest-month mean 77.2°F place this station in temperate, no dry season, hot summer climates (Cfa). Class Cfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, no dry season, hot summer.
- Köppen code
- Cfa
- Group
- Temperate
- Warmest month
- 77.2°F
- Coldest month
- 33.9°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Washington DC Dulles sits across the climate record
Three NOAA fields for Washington DC Dulles's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 63rd percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- 65th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- 50th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Washington DC Dulles compares across U.S. station-mapped locations
Washington DC Dulles's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
73 Top 34% score exceeds 66% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). Below this entry.
- 70–80: 650 station-mapped locations (11%). This entry sits in this band.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Washington DC Dulles's measured station temperature trend
MethodologyAcross 53 complete annual observations from 1964 to 2025, WASHINGTON DC DULLES AP warmed at a fitted rate of 0.25°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Washington DC Dulles primary station fitted change +0.25 °C/decade
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 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 88°F around July 12, short of 90°F on every date, while 102 dates carry a normal low at or below freezing, the coldest 25°F near January 21.
The freezing stretch
The normal low stays at or below 32°F into March 10, then returns to freezing around November 30, covering 102 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is May 8, when 41% of years recorded at least a hundredth of an inch. The driest is October 23 at 27%. Summed across the calendar, that is about 121 wet dates a year.
The widest day
April 20 carries the biggest normal gap between afternoon and dawn, 24°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Washington DC Dulles.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 6.9"
10.3 days with precipitation
Snow: 7.0"
9.1 days with precipitation
Snow: 3.9"
11.0 days with precipitation
Snow: 0.1"
11.0 days with precipitation
12.7 days with precipitation
10.8 days with precipitation
11.0 days with precipitation
9.3 days with precipitation
9.0 days with precipitation
8.1 days with precipitation
Snow: 0.3"
8.6 days with precipitation
Snow: 2.8"
10.2 days with precipitation
Washington DC Dulles spreads its precipitation across the year
Neither half of the year dominates here: June through August take 28% of the annual total and December through February 20%, with neither reaching the 35% that would mark a distinct wet season. Washington DC Dulles has no dry season to plan around, though it does carry a 43.3°F seasonal spread.
The gap between the wettest and driest month still matters: May averages 4.7" and February 2.6". The three wettest months together take 30% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
When it rains in Washington DC Dulles, it arrives in quantity
43.2" of precipitation falls across only about 121 wet days here, averaging 0.36 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 121 a year, 33% of all days
- Average depth per wet day
- 0.36 inches
- Most wet days
- May, about 13
- Fewest wet days
- October, about 8
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Winter brings real snow to Washington DC Dulles
Washington DC Dulles averages 21.0 inches of snowfall a year, with February the snowiest month on the normals, spread across roughly 10 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 21.0 inches of depth.
- Days recording measurable snow: about 10 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 5% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 24
50% probability date
Last Spring Freeze
April 15
50% probability date
Growing Season
192 days
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 | 16% | 33% |
| May | 69% | 6.4 | 16% | 30% |
| June | 69% | 5.8 | 15% | 22% |
| July | 70% | 5.6 | 17% | 24% |
| August | 71% | 5.6 | 19% | 23% |
| September | 73% | 6.0 | 24% | 27% |
| October | 67% | 6.6 | 25% | 30% |
| November | 66% | 7.0 | 21% | 34% |
| December | 65% | 7.4 | 19% | 37% |
Nationwide similar cities
Other rankable U.S. places outside VA closest to Washington DC Dulles on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (56°F here).
- Alton, MO 56°F · 0.0°F off
- Boonville, MO 56°F · 0.0°F off
- Festus, MO 56°F · 0.0°F off
- Hamlin, WV 56°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (43.2" here), excluding temperature-peer places.
- Osceola, MO 43.2" · 0.0" off
- Wilmington, OH 43.2" · 0.0" off
- Jamestown, IN 43.3" · 0.0" off
- Xenia, OH 43.3" · 0.0" off
Snow and freeze rhythm
When cold and snow define Washington DC Dulles
heating led · moderate · mid swing
Washington DC Dulles's energy balance leans toward cold weather: 4,604 annual heating degree days against 1,233 for cooling. Its 43.3°F seasonal range still makes the monthly rows more useful than the annual average alone.
Washington DC Dulles's frost-free season lasts about 192 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Washington DC Dulles coldest normal
January
The monthly mean of 34°F (1°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Washington DC Dulles typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Washington DC Dulles snow peak
February
Washington DC Dulles averages 21.0 inches of snow a year, with February the snowiest month on the normals.
Questions about Washington DC Dulles's climate
How much snow does Washington DC Dulles get? ▼
How many days above 90°F does Washington DC Dulles get? ▼
How much energy does heating and cooling require in Washington DC Dulles? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Washington DC Dulles's primary station: WASHINGTON DC DULLES AP (USW00093738). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Washington DC Dulles; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Washington DC Dulles comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.