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Climate and Average Weather Year Round in Washington Maine, United States

In Washington, the summers are comfortable, the winters are freezing and snowy, and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 13°F to 77°F and is rarely below -2°F or above 85°F.

Based on the tourism score, the best time of year to visit Washington for warm-weather activities is from late June to early September.

Climate in Washington

freezingvery coldcoldcoolwarmcoolcoldvery coldJanFebMarAprMayJunJulAugSepOctNovDecNowNow64%64%42%42%clearovercastprecipitation: 4.3 inprecipitation: 4.3 in2.7 in2.7 inmuggy: 16%muggy: 16%0%0%drydrytourism score: 6.8tourism score: 6.80.00.0
Washington weather by month. Click on each chart for more information.

The warm season lasts for 3.4 months, from June 3 to September 16, with an average daily high temperature above 67°F. The hottest month of the year in Washington is July, with an average high of 76°F and low of 59°F.

The cold season lasts for 3.3 months, from December 2 to March 12, with an average daily high temperature below 38°F. The coldest month of the year in Washington is January, with an average low of 14°F and high of 29°F.

Average High and Low Temperature in Washington

Average High and Low Temperature in WashingtonwarmcoldcoldJanFebMarAprMayJunJulAugSepOctNovDec-10°F-10°F0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FJan 2929°FJan 2929°FJul 2677°FJul 2677°F13°F13°F60°F60°FJun 367°FJun 367°FSep 1667°FSep 1667°FDec 238°FDec 238°FMar 1238°FMar 1238°F50°F50°F51°F51°F26°F26°F23°F23°FNowNow
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
AverageJanFebMarAprMayJunJulAugSepOctNovDec
High 29°F32°F40°F51°F62°F71°F76°F75°F67°F56°F45°F34°F
Temp. 21°F24°F32°F43°F53°F62°F67°F66°F59°F48°F38°F27°F
Low 14°F16°F25°F35°F45°F53°F59°F58°F51°F41°F32°F21°F

The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.

Average Hourly Temperature in Washington

Average Hourly Temperature in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMNowNowfreezingfreezingvery coldvery coldcoldcoldcoolcomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.

Sapporo, Japan (6,118 miles away) is the far-away foreign place with temperatures most similar to Washington (view comparison).

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Compare Washington to another city:

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In Washington, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.

The clearer part of the year in Washington begins around June 25 and lasts for 4.1 months, ending around October 29.

The clearest month of the year in Washington is September, during which on average the sky is clear, mostly clear, or partly cloudy 61% of the time.

The cloudier part of the year begins around October 29 and lasts for 7.9 months, ending around June 25.

The cloudiest month of the year in Washington is May, during which on average the sky is overcast or mostly cloudy 57% of the time.

Cloud Cover Categories in Washington

Cloud Cover Categories in WashingtonclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Sep 264%Sep 264%May 1542%May 1542%Jun 2553%Jun 2553%Oct 2954%Oct 2954%NowNowclearmostly clearpartly cloudymostly cloudyovercast
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.
FractionJanFebMarAprMayJunJulAugSepOctNovDec
Cloudier 52%53%55%56%57%50%43%39%39%43%51%53%
Clearer 48%47%45%44%43%50%57%61%61%57%49%47%

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Washington varies throughout the year.

The wetter season lasts 9.3 months, from March 22 to January 1, with a greater than 28% chance of a given day being a wet day. The month with the most wet days in Washington is June, with an average of 9.6 days with at least 0.04 inches of precipitation.

The drier season lasts 2.7 months, from January 1 to March 22. The month with the fewest wet days in Washington is February, with an average of 6.9 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation in Washington changes throughout the year.

Rain alone is the most common for 9.9 months, from February 22 to December 18. The month with the most days of rain alone in Washington is June, with an average of 9.6 days.

Snow alone is the most common for 2.2 months, from December 18 to February 22. The month with the most days of snow alone in Washington is January, with an average of 3.8 days.

Daily Chance of Precipitation in Washington

Daily Chance of Precipitation in WashingtonsnowrainJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Jun 1334%Jun 1334%Feb 423%Feb 423%Dec 1829%Dec 1829%Mar 2228%Mar 2228%NowNowsnowrainmixed
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).
Days ofJanFebMarAprMayJunJulAugSepOctNovDec
Rain 2.1d2.4d4.6d7.4d9.3d9.6d9.9d8.7d7.8d8.2d6.9d4.0d
Mixed 1.8d1.7d2.1d0.9d0.0d0.0d0.0d0.0d0.0d0.2d1.1d1.9d
Snow 3.8d2.8d1.5d0.2d0.0d0.0d0.0d0.0d0.0d0.1d0.7d3.2d
Any 7.7d6.9d8.2d8.5d9.4d9.6d9.9d8.7d7.8d8.4d8.6d9.1d

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Washington experiences significant seasonal variation in monthly rainfall.

Rain falls throughout the year in Washington. The month with the most rain in Washington is October, with an average rainfall of 4.1 inches.

The month with the least rain in Washington is January, with an average rainfall of 1.4 inches.

Average Monthly Rainfall in Washington

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.
JanFebMarAprMayJunJulAugSepOctNovDec
Rainfall 1.4″1.6″2.4″3.4″3.4″3.3″2.8″2.7″3.4″4.1″3.8″2.4″

Snowfall

As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. Washington experiences extreme seasonal variation in monthly snowfall.

The snowy period of the year lasts for 6.1 months, from October 23 to April 26, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Washington is January, with an average snowfall of 15.7 inches.

The snowless period of the year lasts for 5.9 months, from April 26 to October 23. The least snow falls around July 19, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall in Washington

Average Monthly Snowfall in WashingtonsnowsnowJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in5 in5 in10 in10 in15 in15 in20 in20 in25 in25 in30 in30 in35 in35 inJan 1815.7 inJan 1815.7 inJul 190.0 inJul 190.0 inOct 231.0 inOct 231.0 inApr 261.0 inApr 261.0 in
The average snowfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average rainfall.
JanFebMarAprMayJunJulAugSepOctNovDec
Snowfall 15.7″13.7″9.7″2.3″0.1″0.0″0.0″0.0″0.0″0.5″4.6″12.7″

The length of the day in Washington varies significantly over the course of the year. In 2024, the shortest day is December 21, with 8 hours, 51 minutes of daylight; the longest day is June 20, with 15 hours, 31 minutes of daylight.

Hours of Daylight and Twilight in Washington

Hours of Daylight and Twilight in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 8 minMar 1912 hr, 8 minMar 1915 hr, 31 minJun 2015 hr, 31 minJun 2012 hr, 12 minSep 2212 hr, 12 minSep 228 hr, 51 minDec 218 hr, 51 minDec 21nightnightdayNowNow
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
Hours ofJanFebMarAprMayJunJulAugSepOctNovDec
Daylight 9.3h10.5h12.0h13.5h14.8h15.5h15.1h13.9h12.5h10.9h9.6h8.9h

The earliest sunrise is at 4:52 AM on June 14, and the latest sunrise is 2 hours, 24 minutes later at 7:16 AM on November 2. The earliest sunset is at 3:58 PM on December 8, and the latest sunset is 4 hours, 27 minutes later at 8:25 PM on June 26.

Daylight saving time (DST) is observed in Washington during 2024, starting in the spring on March 10, lasting 7.8 months, and ending in the fall on November 3.

Sunrise & Sunset with Twilight and Daylight Saving Time in Washington

Sunrise & Sunset with Twilight and Daylight Saving Time in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 144:52 AMJun 144:52 AM8:25 PMJun 268:25 PMJun 26Dec 83:58 PMDec 83:58 PM7:16 AMNov 27:16 AMNov 2Mar 10DSTMar 10DSTDSTNov 3DSTNov 3daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
The solar day over the course of the year 2024. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight saving time are indicated by the 'DST' labels.

The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation.

Solar Elevation and Azimuth in Washington

Solar Elevation and Azimuth in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AM000101010102020203030304040506000010101020202020303040405050602269NowNow
northeastsouthwest
Solar elevation and azimuth over the course of the year 2024. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).

The figure below presents a compact representation of key lunar data for 2024. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases.

Moon Rise, Set & Phases in Washington

The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.

We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.

Washington experiences some seasonal variation in the perceived humidity.

The muggier period of the year lasts for 2.8 months, from June 18 to September 11, during which time the comfort level is muggy, oppressive, or miserable at least 4% of the time. The month with the most muggy days in Washington is July, with 4.2 days that are muggy or worse.

The least muggy day of the year is March 1, when muggy conditions are essentially unheard of.

Humidity Comfort Levels in Washington

Humidity Comfort Levels in WashingtonmuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Mar 10%Mar 10%Jul 2916%Jul 2916%Jun 184%Jun 184%Sep 114%Sep 114%NowNowmuggymuggycomfortablecomfortabledrydryhumidhumid
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.
JanFebMarAprMayJunJulAugSepOctNovDec
Muggy days 0.0d0.0d0.0d0.0d0.1d1.1d4.2d3.7d0.9d0.0d0.0d0.0d

This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.

The average hourly wind speed in Washington experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 6.0 months, from October 21 to April 21, with average wind speeds of more than 6.6 miles per hour. The windiest month of the year in Washington is February, with an average hourly wind speed of 8.6 miles per hour.

The calmer time of year lasts for 6.0 months, from April 21 to October 21. The calmest month of the year in Washington is July, with an average hourly wind speed of 4.7 miles per hour.

Average Wind Speed in Washington

Average Wind Speed in WashingtonwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mph14 mph14 mphFeb 238.7 mphFeb 238.7 mphJul 304.5 mphJul 304.5 mphOct 216.6 mphOct 216.6 mphApr 216.6 mphApr 216.6 mphNowNow
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Wind Speed (mph) 8.38.68.26.95.65.04.74.75.46.57.27.6

The predominant average hourly wind direction in Washington varies throughout the year.

The wind is most often from the north for 2.4 months, from February 10 to April 22, with a peak percentage of 38% on March 3. The wind is most often from the south for 5.5 months, from April 22 to October 5, with a peak percentage of 43% on July 1. The wind is most often from the west for 4.2 months, from October 5 to February 10, with a peak percentage of 43% on January 1.

Wind Direction in Washington

Wind Direction in WashingtonWNSWJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestsouthnortheast
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Washington is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.

The average water temperature experiences significant seasonal variation over the course of the year.

The time of year with warmer water lasts for 3.0 months, from June 29 to September 28, with an average temperature above 55°F. The month of the year in Washington with the warmest water is August, with an average temperature of 60°F.

The time of year with cooler water lasts for 3.4 months, from January 10 to April 24, with an average temperature below 42°F. The month of the year in Washington with the coolest water is March, with an average temperature of 38°F.

Average Water Temperature in Washington

Average Water Temperature in WashingtonwarmcoolJanFebMarAprMayJunJulAugSepOctNovDec35°F35°F40°F40°F45°F45°F50°F50°F55°F55°F60°F60°F65°F65°FAug 1260°FAug 1260°F37°FMar 937°FMar 9Jun 2955°FJun 2955°FSep 2855°FSep 2855°FJan 1042°FJan 1042°FApr 2442°FApr 2442°FNowNow
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 41°F38°F38°F40°F46°F52°F58°F60°F57°F53°F49°F45°F

To characterize how pleasant the weather is in Washington throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best time of year to visit Washington for general outdoor tourist activities is from late June to early September, with a peak score in the last week of July.

Tourism Score in Washington

Tourism Score in Washingtonbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.86.80.00.06.86.8NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationtourism score
The tourism score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit Washington for hot-weather activities is from early July to mid August, with a peak score in the last week of July.

Beach/Pool Score in Washington

Beach/Pool Score in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec002244668810104.34.30.00.0NowNowtemperaturetemperature cloudscloudsprecipitationprecipitationbeach/pool score
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

The growing season in Washington typically lasts for 5.5 months (165 days), from around April 27 to around October 9, rarely starting before April 11 or after May 13, and rarely ending before September 23 or after October 26.

Time Spent in Various Temperature Bands and the Growing Season in Washington

Time Spent in Various Temperature Bands and the Growing Season in Washingtongrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Apr 2750%Apr 2750%Oct 950%Oct 950%May 1390%May 1390%Sep 2390%Sep 2390%Apr 1110%Apr 1110%Oct 2610%Oct 2610%0%Feb 110%Feb 11Jul 23100%Jul 23100%NowNowfrigidfreezingvery coldcoldcoolcomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

Based on growing degree days alone, the first spring blooms in Washington should appear around May 13, only rarely appearing before May 4 or after May 22.

Growing Degree Days in Washington

Growing Degree Days in WashingtonJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F500°F500°F1,000°F1,000°F1,500°F1,500°F2,000°F2,000°FMay 1390°FMay 1390°FJul 21900°FJul 21900°FSep 191,800°FSep 191,800°FDec 311,993°FDec 311,993°F
The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.

The average daily incident shortwave solar energy experiences extreme seasonal variation over the course of the year.

The brighter period of the year lasts for 3.5 months, from May 7 to August 23, with an average daily incident shortwave energy per square meter above 5.7 kWh. The brightest month of the year in Washington is July, with an average of 6.5 kWh.

The darker period of the year lasts for 3.4 months, from October 30 to February 10, with an average daily incident shortwave energy per square meter below 2.5 kWh. The darkest month of the year in Washington is December, with an average of 1.5 kWh.

Average Daily Incident Shortwave Solar Energy in Washington

Average Daily Incident Shortwave Solar Energy in WashingtonbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJun 306.7 kWhJun 306.7 kWhDec 161.4 kWhDec 161.4 kWhMay 75.7 kWhMay 75.7 kWhAug 235.7 kWhAug 235.7 kWhOct 302.5 kWhOct 302.5 kWhFeb 102.5 kWhFeb 102.5 kWhNowNow
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.
JanFebMarAprMayJunJulAugSepOctNovDec
Solar Energy (kWh) 1.82.63.74.95.96.56.55.84.63.11.91.5

For the purposes of this report, the geographical coordinates of Washington are 44.274 deg latitude, -69.367 deg longitude, and 295 ft elevation.

The topography within 2 miles of Washington contains only modest variations in elevation, with a maximum elevation change of 328 feet and an average elevation above sea level of 298 feet. Within 10 miles contains only modest variations in elevation (1,076 feet). Within 50 miles also contains very significant variations in elevation (1,837 feet).

The area within 2 miles of Washington is covered by trees (90%) and water (10%), within 10 miles by trees (89%), and within 50 miles by trees (58%) and water (35%).

This report illustrates the typical weather in Washington, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.

Temperature and Dew Point

There are 5 weather stations near enough to contribute to our estimation of the temperature and dew point in Washington.

For each station, the records are corrected for the elevation difference between that station and Washington according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.

The estimated value at Washington is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Washington and a given station.

The stations contributing to this reconstruction are:

To get a sense of how much these sources agree with each other, you can view a comparison of Washington and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data.

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus.

All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.

Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.

Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.

Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .

Time zones for airports and weather stations are provided by AskGeo.com .

Maps are © OpenStreetMap contributors.

Disclaimer

The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.

We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.

We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.

Please review our full terms contained on our Terms of Service page.