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

In Rochester, the summers are short, warm, dry, and partly cloudy and the winters are very cold, wet, and overcast. Over the course of the year, the temperature typically varies from 35°F to 79°F and is rarely below 24°F or above 90°F.

Based on the tourism score, the best time of year to visit Rochester for warm-weather activities is from early July to mid August.

Climate in Rochester

coldcoolcomfortablewarmcoolcoldJanFebMarAprMayJunJulAugSepOctNovDecNowNow78%78%22%22%clearovercastprecipitation: 10.1 inprecipitation: 10.1 in0.5 in0.5 inmuggy: 1%muggy: 1%0%0%drydrytourism score: 6.0tourism score: 6.00.10.1
Rochester weather by month. Click on each chart for more information.

The warm season lasts for 2.9 months, from June 20 to September 16, with an average daily high temperature above 72°F. The hottest month of the year in Rochester is August, with an average high of 78°F and low of 52°F.

The cool season lasts for 3.3 months, from November 12 to February 22, with an average daily high temperature below 51°F. The coldest month of the year in Rochester is December, with an average low of 35°F and high of 45°F.

Average High and Low Temperature in Rochester

Average High and Low Temperature in RochesterwarmcoolcoolJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FDec 1945°FDec 1945°FAug 279°FAug 279°F35°F35°F53°F53°FJun 2072°FJun 2072°FSep 1672°FSep 1672°FNov 1251°FNov 1251°FFeb 2251°FFeb 2251°F49°F49°F48°F48°F39°F39°F36°F36°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 46°F50°F55°F60°F66°F72°F78°F78°F72°F61°F51°F45°F
Temp. 40°F42°F45°F49°F54°F59°F64°F64°F59°F51°F44°F39°F
Low 35°F36°F38°F40°F45°F49°F52°F52°F48°F44°F39°F35°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 Rochester

Average Hourly Temperature in RochesterJanFebMarAprMayJunJulAugSepOctNovDec12 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 AMNowNowvery coldvery coldcoldcoolcoolcomfortablewarm
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.

El Bolsón, Argentina (6,907 miles away); Bande, Spain (5,132 miles); and Pruniers-en-Sologne, France (5,135 miles) are the far-away foreign places with temperatures most similar to Rochester (view comparison).

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

The clearer part of the year in Rochester begins around June 11 and lasts for 3.8 months, ending around October 6.

The clearest month of the year in Rochester is August, during which on average the sky is clear, mostly clear, or partly cloudy 72% of the time.

The cloudier part of the year begins around October 6 and lasts for 8.2 months, ending around June 11.

The cloudiest month of the year in Rochester is January, during which on average the sky is overcast or mostly cloudy 77% of the time.

Cloud Cover Categories in Rochester

Cloud Cover Categories in RochesterclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Aug 278%Aug 278%Jan 1522%Jan 1522%Jun 1150%Jun 1150%Oct 650%Oct 650%NowNowclearmostly cloudyovercastpartly cloudymostly clear
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 77%74%73%66%58%47%28%28%38%58%73%77%
Clearer 23%26%27%34%42%53%72%72%62%42%27%23%

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

The wetter season lasts 6.7 months, from October 7 to April 29, with a greater than 34% chance of a given day being a wet day. The month with the most wet days in Rochester is November, with an average of 17.5 days with at least 0.04 inches of precipitation.

The drier season lasts 5.3 months, from April 29 to October 7. The month with the fewest wet days in Rochester is July, with an average of 3.1 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. The month with the most days of rain alone in Rochester is November, with an average of 17.1 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 59% on November 16.

Daily Chance of Precipitation in Rochester

Daily Chance of Precipitation in RochesterwetwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Nov 1760%Nov 1760%Aug 27%Aug 27%Oct 734%Oct 734%Apr 2934%Apr 2934%NowNowrainmixed
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 14.4d13.6d15.2d12.2d8.9d6.5d3.1d3.4d6.6d12.6d17.1d15.6d
Mixed 1.0d0.5d0.3d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.4d0.9d
Snow 0.2d0.1d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.0d0.2d
Any 15.7d14.2d15.5d12.2d8.9d6.5d3.1d3.4d6.6d12.6d17.5d16.7d

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. Rochester experiences extreme seasonal variation in monthly rainfall.

Rain falls throughout the year in Rochester. The month with the most rain in Rochester is November, with an average rainfall of 9.8 inches.

The month with the least rain in Rochester is July, with an average rainfall of 0.7 inches.

Average Monthly Rainfall in Rochester

Average Monthly Rainfall in RochesterJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in5 in5 in10 in10 in15 in15 inNov 2210.1 inNov 2210.1 inJul 280.5 inJul 280.5 inNowNow
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 7.9″7.1″6.2″4.1″2.4″1.6″0.7″0.8″2.2″5.6″9.8″8.8″

Snowfall

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

The snowy period of the year lasts for 2.0 months, from December 6 to February 7, with a sliding 31-day snowfall of at least 1.0 inches. The month with the most snow in Rochester is January, with an average snowfall of 2.1 inches.

The snowless period of the year lasts for 10.0 months, from February 7 to December 6. The least snow falls around July 14, with an average total accumulation of 0.0 inches.

Average Monthly Snowfall in Rochester

Average Monthly Snowfall in RochestersnowsnowJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in2 in2 in4 in4 in6 in6 in8 in8 in10 in10 inJan 72.5 inJan 72.5 inJul 140.0 inJul 140.0 inDec 61.0 inDec 61.0 inNowNow
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 2.1″0.7″0.1″0.0″0.0″0.0″0.0″0.0″0.0″0.0″0.3″1.7″

The length of the day in Rochester varies significantly over the course of the year. In 2024, the shortest day is December 21, with 8 hours, 32 minutes of daylight; the longest day is June 20, with 15 hours, 52 minutes of daylight.

Hours of Daylight and Twilight in Rochester

Hours of Daylight and Twilight in RochesterJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 9 minMar 1912 hr, 9 minMar 1915 hr, 52 minJun 2015 hr, 52 minJun 2012 hr, 12 minSep 2212 hr, 12 minSep 228 hr, 32 minDec 218 hr, 32 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 9.0h10.3h12.0h13.7h15.1h15.8h15.4h14.1h12.5h10.8h9.4h8.6h

The earliest sunrise is at 5:17 AM on June 15, and the latest sunrise is 2 hours, 40 minutes later at 7:57 AM on January 1. The earliest sunset is at 4:23 PM on December 10, and the latest sunset is 4 hours, 47 minutes later at 9:10 PM on June 25.

Daylight saving time (DST) is observed in Rochester 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 Rochester

Sunrise & Sunset with Twilight and Daylight Saving Time in RochesterJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 155:17 AMJun 155:17 AM9:10 PMJun 259:10 PMJun 25Dec 104:23 PMDec 104:23 PM7:57 AMJan 17:57 AMJan 1Mar 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 Rochester

Solar Elevation and Azimuth in RochesterJanFebMarAprMayJunJulAugSepOctNovDec12 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 AM0001010101020203030304040506000010101020202020303040405050602067NowNow
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 Rochester

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.

The perceived humidity level in Rochester, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.

Humidity Comfort Levels in Rochester

Humidity Comfort Levels in RochesterJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Feb 60%Feb 60%Aug 71%Aug 71%NowNowcomfortablecomfortabledrydryhumidhumid
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 0.0d0.0d0.0d0.0d0.0d0.0d0.1d0.1d0.0d0.0d0.0d0.0d

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 Rochester experiences mild seasonal variation over the course of the year.

The windier part of the year lasts for 5.9 months, from October 18 to April 15, with average wind speeds of more than 4.0 miles per hour. The windiest month of the year in Rochester is November, with an average hourly wind speed of 4.6 miles per hour.

The calmer time of year lasts for 6.1 months, from April 15 to October 18. The calmest month of the year in Rochester is August, with an average hourly wind speed of 3.3 miles per hour.

Average Wind Speed in Rochester

Average Wind Speed in RochesterwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph1 mph1 mph2 mph2 mph3 mph3 mph4 mph4 mph5 mph5 mph6 mph6 mph7 mph7 mph8 mph8 mphNov 304.7 mphNov 304.7 mphAug 13.2 mphAug 13.2 mphOct 184.0 mphOct 184.0 mphApr 154.0 mphApr 154.0 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) 4.44.44.34.03.73.63.33.33.53.94.64.6

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

The wind is most often from the west for 5.9 months, from April 8 to October 4, with a peak percentage of 66% on June 28. The wind is most often from the south for 6.1 months, from October 4 to April 8, with a peak percentage of 46% on January 1.

Wind Direction in Rochester

Wind Direction in RochesterSWSJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNowwestsoutheastnorth
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).

Rochester 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 some seasonal variation over the course of the year.

The time of year with warmer water lasts for 3.5 months, from June 14 to September 30, with an average temperature above 56°F. The month of the year in Rochester with the warmest water is August, with an average temperature of 58°F.

The time of year with cooler water lasts for 4.0 months, from December 6 to April 6, with an average temperature below 50°F. The month of the year in Rochester with the coolest water is February, with an average temperature of 48°F.

Average Water Temperature in Rochester

The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
WaterJanFebMarAprMayJunJulAugSepOctNovDec
Temperature 48°F48°F49°F51°F54°F56°F57°F58°F57°F55°F52°F49°F

To characterize how pleasant the weather is in Rochester 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 Rochester for general outdoor tourist activities is from early July to mid August, with a peak score in the last week of July.

Tourism Score in Rochester

Tourism Score in Rochesterbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.06.00.10.1NowNowtemperaturetemperature 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 Rochester for hot-weather activities is from mid July to mid August, with a peak score in the first week of August.

Beach/Pool Score in Rochester

Beach/Pool Score in RochesterJanFebMarAprMayJunJulAugSepOctNovDec002244668810101.91.90.00.0NowNow 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 Rochester typically lasts for 6.1 months (185 days), from around April 19 to around October 22, rarely starting before March 27 or after May 10, and rarely ending before September 28 or after November 13.

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

Time Spent in Various Temperature Bands and the Growing Season in Rochestergrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%50%Apr 1950%Apr 1950%Oct 2250%Oct 2290%May 1090%May 1090%Sep 2890%Sep 2810%Mar 2710%Mar 2710%Nov 1310%Nov 130%Feb 20%Feb 2Jul 18100%Jul 18100%freezingvery coldcoldcoolcomfortablehot
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 Rochester should appear around April 15, only rarely appearing before March 28 or after April 30.

Growing Degree Days in Rochester

Growing Degree Days in RochesterJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F500°F500°F1,000°F1,000°F1,500°F1,500°F2,000°F2,000°FApr 1590°FApr 1590°FJul 22900°FJul 22900°FOct 131,800°FOct 131,800°FDec 311,883°FDec 311,883°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 3.1 months, from May 21 to August 23, with an average daily incident shortwave energy per square meter above 5.7 kWh. The brightest month of the year in Rochester is July, with an average of 6.8 kWh.

The darker period of the year lasts for 4.0 months, from October 24 to February 22, with an average daily incident shortwave energy per square meter below 2.1 kWh. The darkest month of the year in Rochester is December, with an average of 0.9 kWh.

Average Daily Incident Shortwave Solar Energy in Rochester

Average Daily Incident Shortwave Solar Energy in RochesterbrightdarkdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhJul 156.9 kWhJul 156.9 kWhDec 240.9 kWhDec 240.9 kWhMay 215.7 kWhMay 215.7 kWhAug 235.7 kWhAug 235.7 kWhOct 242.1 kWhOct 242.1 kWhFeb 222.1 kWhFeb 222.1 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) 1.11.82.94.35.56.36.86.04.42.51.30.9

For the purposes of this report, the geographical coordinates of Rochester are 46.822 deg latitude, -123.096 deg longitude, and 141 ft elevation.

The topography within 2 miles of Rochester contains only modest variations in elevation, with a maximum elevation change of 285 feet and an average elevation above sea level of 141 feet. Within 10 miles contains only modest variations in elevation (2,142 feet). Within 50 miles contains large variations in elevation (6,145 feet).

The area within 2 miles of Rochester is covered by cropland (69%), artificial surfaces (18%), and trees (11%), within 10 miles by trees (55%) and cropland (22%), and within 50 miles by trees (58%) and shrubs (17%).

This report illustrates the typical weather in Rochester, 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 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Rochester.

For each station, the records are corrected for the elevation difference between that station and Rochester 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 Rochester is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Rochester 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 Rochester 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.