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Average Weather in Southampton United Kingdom

In Southampton, the summers are comfortable; the winters are long, very cold, and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 37°F to 70°F and is rarely below 28°F or above 78°F.

Climate Summary

coldcoolcomfortablecoolcoldJanFebMarAprMayJunJulAugSepOctNovDec58%58%31%31%overcastclearprecipitation: 2.7 inprecipitation: 2.7 in1.3 in1.3 inmuggy: 1%muggy: 1%0%0%drydrytourism score: 7.1tourism score: 7.10.20.2
Click on each chart for more information.

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

Temperature

The warm season lasts for 3.0 months, from June 15 to September 13, with an average daily high temperature above 66°F. The hottest day of the year is July 27, with an average high of 70°F and low of 57°F.

The cool season lasts for 4.0 months, from November 21 to March 20, with an average daily high temperature below 51°F. The coldest day of the year is February 7, with an average low of 37°F and high of 47°F.

Average High and Low Temperature

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.

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

Average Hourly Temperature in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec12 AM4 AM8 AM12 PM4 PM8 PM12 AMcoldcoolvery coldcomfortable
The average hourly temperature, color coded into bands: 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 shaded overlays indicate night and civil twilight.

Clouds

In Southampton, 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 Southampton begins around April 2 and lasts for 6.5 months, ending around October 16. On July 18, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 58% of the time, and overcast or mostly cloudy 41% of the time.

The cloudier part of the year begins around October 16 and lasts for 5.5 months, ending around April 2. On December 25, the cloudiest day of the year, the sky is overcast or mostly cloudy 69% of the time, and clear, mostly clear, or partly cloudy 31% of the time.

Cloud Cover Categories

Cloud Cover Categories in SouthamptonclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jul 1858%Jul 1858%Dec 2531%Dec 2531%Apr 245%Apr 245%Oct 1645%Oct 1645%clearpartly cloudymostly cloudyovercastmostly clear
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.

Precipitation

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

The wetter season lasts 4.1 months, from October 3 to February 6, with a greater than 28% chance of a given day being a wet day. The chance of a wet day peaks at 36% on December 30.

The drier season lasts 7.9 months, from February 6 to October 3. The smallest chance of a wet day is 20% on July 24.

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 throughout the year is rain alone, with a peak probability of 35% on December 30.

Daily Chance of Precipitation

Daily Chance of Precipitation in SouthamptonwetwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%10%20%30%40%50%60%70%80%90%100%Dec 3036%Dec 3036%Jul 2420%Jul 2420%Oct 328%Oct 328%Feb 628%Feb 628%rain
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).

Rainfall

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. Southampton experiences some seasonal variation in monthly rainfall.

Rain falls throughout the year in Southampton. The most rain falls during the 31 days centered around November 9, with an average total accumulation of 2.7 inches.

The least rain falls around July 23, with an average total accumulation of 1.3 inches.

Average Monthly Rainfall

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 liquid-equivalent snowfall.

Sun

The length of the day in Southampton varies extremely over the course of the year. In 2017, the shortest day is December 21, with 7 hours, 56 minutes of daylight; the longest day is June 21, with 16 hours, 32 minutes of daylight.

Hours of Daylight and Twilight

Hours of Daylight and Twilight in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 7 minMar 2012 hr, 7 minMar 2016 hr, 32 minJun 2116 hr, 32 minJun 2112 hr, 12 minSep 2212 hr, 12 minSep 227 hr, 56 minDec 217 hr, 56 minDec 21nightnightday
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.

The earliest sunrise is at 4:51 AM on June 17, and the latest sunrise is 3 hours, 17 minutes later at 8:08 AM on December 31. The earliest sunset is at 3:59 PM on December 12, and the latest sunset is 5 hours, 24 minutes later at 9:23 PM on June 25.

Daylight saving time (DST) is observed in Southampton during 2017, starting in the spring on March 26, lasting 7.1 months, and ending in the fall on October 29.

Sunrise & Sunset with Twilight and Daylight Saving Time

Sunrise & Sunset with Twilight and Daylight Saving Time in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMJun 174:51 AMJun 174:51 AM9:23 PMJun 259:23 PMJun 25Dec 123:59 PMDec 123:59 PM8:08 AMDec 318:08 AMDec 31Mar 26DSTMar 26DSTDSTOct 29DSTOct 29daynightnightnightnightSolarMidnightSolarMidnightSolarNoonSunset
The solar day over the course of the year 2017. 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.

Humidity

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 Southampton, 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

Humidity Comfort Levels in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec0%10%20%30%40%50%60%70%80%90%100%Jan 200%Jan 200%Aug 121%Aug 121%drydrycomfortablecomfortable
The percentage of time spent at various humidity comfort levels, categorized by dew point: dry < 55°F < comfortable < 60°F < humid < 65°F < muggy < 70°F < oppressive < 75°F < miserable.

Wind

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 Southampton experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 5.5 months, from October 10 to March 26, with average wind speeds of more than 12.7 miles per hour. The windiest day of the year is January 3, with an average hourly wind speed of 14.9 miles per hour.

The calmer time of year lasts for 6.5 months, from March 26 to October 10. The calmest day of the year is August 3, with an average hourly wind speed of 10.5 miles per hour.

Average Wind Speed

Average Wind Speed in SouthamptonwindywindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph2 mph4 mph6 mph8 mph10 mph12 mph14 mph16 mph18 mph20 mph22 mph24 mphJan 314.9 mphJan 314.9 mphAug 310.5 mphAug 310.5 mphOct 1012.7 mphOct 1012.7 mphMar 2612.7 mphMar 2612.7 mph
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.

The predominant average hourly wind direction in Southampton is from the west throughout the year.

Wind Direction

Wind Direction in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%eastwestnorthsouth
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions (north, east, south, and west), excluding hours in which the mean wind speed is less than 1 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Water Temperature

Southampton 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 3.2 months, from July 7 to October 15, with an average temperature above 60°F. The day of the year with the warmest water is August 23, with an average temperature of 63°F.

The time of year with cooler water lasts for 3.8 months, from December 31 to April 24, with an average temperature below 49°F. The day of the year with the coolest water is March 3, with an average temperature of 46°F.

Average Water Temperature

The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.

Best Time of Year to Visit

To characterize how pleasant the weather is in Southampton 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 Southampton for general outdoor tourist activities is from late June to early September, with a peak score in the last week of July.

Tourism Score

Tourism Score in Southamptonbest timeJanFebMarAprMayJunJulAugSepOctNovDec02468107.17.10.20.2 precipitationprecipitationcloudscloudstemperaturetemperaturetourism 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 Southampton for hot-weather activities is from mid July to mid August, with a peak score in the last week of July.

Beach/Pool Score

Beach/Pool Score in SouthamptonJanFebMarAprMayJunJulAugSepOctNovDec02468102.72.70.00.0 precipitationprecipitationcloudscloudstemperaturetemperature
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.

Growing Season

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 Southampton typically lasts for 7.5 months (229 days), from around March 29 to around November 13, rarely starting before February 17 or after April 23, and rarely ending before October 17 or after December 12.

Time Spent in Various Temperature Bands and the Growing Season

Time Spent in Various Temperature Bands and the Growing Season in Southamptongrowing seasonJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%50%Mar 2950%Mar 2950%Nov 1350%Nov 1390%Apr 2390%Apr 2390%Oct 1790%Oct 1710%Feb 1710%Feb 1710%Dec 1210%Dec 120%Jan 160%Jan 16Jul 20100%Jul 20100%coldcoolvery coldcomfortablewarm
The percentage of time spent in various temperature bands: 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 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 Southampton should appear around April 28, only rarely appearing before April 11 or after May 16.

Growing Degree Days

The average growing degree days accumulated over the course of the year, with 25th to 75th and 10th to 90th percentile bands.

Solar Energy

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 3.4 months, from May 3 to August 16, with an average daily incident shortwave energy per square meter above 5.4 kWh. The brightest day of the year is June 28, with an average of 6.6 kWh.

The darker period of the year lasts for 3.8 months, from October 26 to February 20, with an average daily incident shortwave energy per square meter below 1.9 kWh. The darkest day of the year is December 26, with an average of 0.7 kWh.

Average Daily Incident Shortwave Solar Energy

The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

Topography

For the purposes of this report, the geographical coordinates of Southampton are 50.904 deg latitude, -1.404 deg longitude, and 46 ft elevation.

The topography within 2 miles of Southampton contains only modest variations in elevation, with a maximum elevation change of 194 feet and an average elevation above sea level of 35 feet. Within 10 miles contains only modest variations in elevation (522 feet). Within 50 miles contains significant variations in elevation (1,030 feet).

The area within 2 miles of Southampton is covered by artificial surfaces (74%) and water (18%), within 10 miles by grassland (30%) and artificial surfaces (21%), and within 50 miles by water (34%) and cropland (29%).

Data Sources

This report illustrates the typical weather in Southampton, 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 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Southampton.

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

The stations contributing to this reconstruction are: Southampton / Weather Centre (93%, 6 kilometers, northeast) and Bournemouth Airport (7%, 34 kilometers, southwest).

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , 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 aiports and weather stations are provided by AskGeo.com .

Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.

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.