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Average Weather at Imperatriz Brazil

At Imperatriz, the wet season is overcast, the dry season is partly cloudy, and it is hot and oppressive year round. Over the course of the year, the temperature typically varies from 68°F to 95°F and is rarely below 64°F or above 99°F.

Based on the beach/pool score, the best time of year to visit Imperatriz for hot-weather activities is from early June to late August.

Climate Summary

hotJanFebMarAprMayJunJulAugSepOctNovDecNowNow66%66%17%17%overcastprecipitation: 9.0 inprecipitation: 9.0 in0.2 in0.2 inmuggy: 100%muggy: 100%72%72%beach/pool score: 6.2beach/pool score: 6.23.73.7
Click on each chart for more information.

Temperature

The temperature at Imperatriz varies so little throughout the year that it is not entirely meaningful to discuss hot and cold seasons.

Average High and Low Temperature

Average High and Low Temperature at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F10°F10°F20°F20°F30°F30°F40°F40°F50°F50°F60°F60°F70°F70°F80°F80°F90°F90°F100°F100°FJul 2693°FJul 2693°FAug 2895°FAug 2895°F68°F68°F70°F70°FOct 194°FOct 194°FDec 1790°FDec 1790°FApr 2590°FApr 2590°F74°F74°F74°F74°F74°F74°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.

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 at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec12 AM12 AM4 AM4 AM8 AM8 AM12 PM12 PM4 PM4 PM8 PM8 PM12 AM12 AMNowNowcomfortablewarmwarmhotcomfortable
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.

Huixtla, Mexico (3,399 miles away) is the far-away foreign place with temperatures most similar to Imperatriz (view comparison).

Clouds

At Imperatriz, 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 at Imperatriz begins around June 3 and lasts for 4.3 months, ending around October 11. On July 26, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 66% of the time, and overcast or mostly cloudy 34% of the time.

The cloudier part of the year begins around October 11 and lasts for 7.7 months, ending around June 3. On March 12, the cloudiest day of the year, the sky is overcast or mostly cloudy 83% of the time, and clear, mostly clear, or partly cloudy 17% of the time.

Cloud Cover Categories

Cloud Cover Categories at ImperatrizclearercloudiercloudierJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%Jul 2666%Jul 2666%Mar 1217%Mar 1217%Jun 341%Jun 341%Oct 1142%Oct 1142%NowNowclearpartly cloudyovercastmostly 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.

Precipitation

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

The wetter season lasts 6.0 months, from November 8 to May 7, with a greater than 38% chance of a given day being a wet day. The chance of a wet day peaks at 73% on March 19.

The drier season lasts 6.0 months, from May 7 to November 8. The smallest chance of a wet day is 3% on August 10.

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 73% on March 19.

Daily Chance of Precipitation

Daily Chance of Precipitation at ImperatrizwetwetdryJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Mar 1973%Mar 1973%Aug 103%Aug 103%Jan 161%Jan 161%Nov 838%Nov 838%May 738%May 738%NowNowrain
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. Imperatriz experiences extreme seasonal variation in monthly rainfall.

The rainy period of the year lasts for 9.7 months, from August 26 to June 17, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around February 17, with an average total accumulation of 9.0 inches.

The rainless period of the year lasts for 2.3 months, from June 17 to August 26. The least rain falls around July 30, with an average total accumulation of 0.2 inches.

Average Monthly Rainfall

Average Monthly Rainfall at ImperatrizrainrainJanFebMarAprMayJunJulAugSepOctNovDec0 in0 in5 in5 in10 in10 in15 in15 inFeb 179.0 inFeb 179.0 inJul 300.2 inJul 300.2 inJun 170.5 inJun 170.5 in
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 at Imperatriz does not vary substantially over the course of the year, staying within 26 minutes of 12 hours throughout. In 2021, the shortest day is June 21, with 11 hours, 48 minutes of daylight; the longest day is December 21, with 12 hours, 27 minutes of daylight.

Hours of Daylight and Twilight

Hours of Daylight and Twilight at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hr12 hr, 6 minSep 2212 hr, 6 minSep 2212 hr, 27 minDec 2112 hr, 27 minDec 2112 hr, 7 minMar 2012 hr, 7 minMar 2011 hr, 48 minJun 2111 hr, 48 minJun 21daydaynightNowNow
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 5:43 AM on November 12, and the latest sunrise is 38 minutes later at 6:21 AM on July 17. The earliest sunset is at 6:01 PM on May 22, and the latest sunset is 32 minutes later at 6:33 PM on February 1.

Daylight saving time (DST) is not observed at Imperatriz during 2021.

Sunrise & Sunset with Twilight

Sunrise & Sunset with Twilight at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMNov 125:43 AMNov 125:43 AM6:33 PMFeb 16:33 PMFeb 1May 226:01 PMMay 226:01 PM6:21 AMJul 176:21 AMJul 17daynightSolarMidnightSolarMidnightSolarNoonSunriseSunsetNowNow
The solar day over the course of the year 2021. 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.

Moon

The figure below presents a compact representation of key lunar data for 2021. 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

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.

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.

Imperatriz experiences some seasonal variation in the perceived humidity.

The muggier period of the year lasts for 11 months, from August 29 to July 23, during which time the comfort level is muggy, oppressive, or miserable at least 79% of the time. The muggiest day of the year is March 14, with muggy conditions 100% of the time.

The least muggy day of the year is August 10, with muggy conditions 72% of the time.

Humidity Comfort Levels

Humidity Comfort Levels at ImperatrizmuggymuggyJanFebMarAprMayJunJulAugSepOctNovDec0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%Aug 1072%Aug 1072%100%Mar 14100%Mar 14NowNowmiserablemiserableoppressiveoppressivemuggymuggycomfortablecomfortable
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.

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 at Imperatriz experiences mild seasonal variation over the course of the year.

The windier part of the year lasts for 4.2 months, from June 17 to October 22, with average wind speeds of more than 5.7 miles per hour. The windiest day of the year is August 30, with an average hourly wind speed of 7.1 miles per hour.

The calmer time of year lasts for 7.8 months, from October 22 to June 17. The calmest day of the year is March 29, with an average hourly wind speed of 4.3 miles per hour.

Average Wind Speed

Average Wind Speed at ImperatrizwindyJanFebMarAprMayJunJulAugSepOctNovDec0 mph0 mph1 mph1 mph2 mph2 mph3 mph3 mph4 mph4 mph5 mph5 mph6 mph6 mph7 mph7 mph8 mph8 mph9 mph9 mph10 mph10 mph11 mph11 mphAug 307.1 mphAug 307.1 mphMar 294.3 mphMar 294.3 mphJun 175.7 mphJun 175.7 mphOct 225.7 mphOct 225.7 mphNowNow
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 at Imperatriz varies throughout the year.

The wind is most often from the north for 3.0 months, from January 6 to April 7, with a peak percentage of 48% on March 12. The wind is most often from the east for 9.0 months, from April 7 to January 6, with a peak percentage of 41% on January 1.

Wind Direction

Wind Direction at ImperatrizNEJanFebMarAprMayJunJulAugSepOctNovDec0%100%20%80%40%60%60%40%80%20%100%0%NowNoweastnorthwestsouth
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).

Best Time of Year to Visit

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

Tourism Score

Tourism Score at Imperatrizbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810104.74.72.62.6NowNowprecipitationprecipitationcloudscloudstourism 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 Imperatriz for hot-weather activities is from early June to late August, with a peak score in the third week of July.

Beach/Pool Score

Beach/Pool Score at Imperatrizbest timeJanFebMarAprMayJunJulAugSepOctNovDec002244668810106.26.23.73.7NowNowprecipitationprecipitationcloudscloudstemperaturetemperature beach/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.

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).

Temperatures at Imperatriz are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.

Time Spent in Various Temperature Bands and the Growing Season

Time Spent in Various Temperature Bands and the Growing Season at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%100%Jan 1100%Jan 1100%Jul 3100%Jul 3NowNowcomfortablewarmhotsweltering
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.

Growing Degree Days

Growing Degree Days at ImperatrizJanFebMarAprMayJunJulAugSepOctNovDec0°F0°F2,000°F2,000°F4,000°F4,000°F6,000°F6,000°F8,000°F8,000°F10,000°F10,000°FJul 490°FJul 490°FSep 11,800°FSep 11,800°FJun 3010,908°FJun 3010,908°F
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 some seasonal variation over the course of the year.

The brighter period of the year lasts for 2.2 months, from August 7 to October 12, with an average daily incident shortwave energy per square meter above 6.4 kWh. The brightest day of the year is September 11, with an average of 6.8 kWh.

The darker period of the year lasts for 5.3 months, from December 17 to May 26, with an average daily incident shortwave energy per square meter below 5.2 kWh. The darkest day of the year is March 29, with an average of 4.8 kWh.

Average Daily Incident Shortwave Solar Energy

Average Daily Incident Shortwave Solar Energy at ImperatrizbrightdarkJanFebMarAprMayJunJulAugSepOctNovDec0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWhSep 116.8 kWhSep 116.8 kWhMar 294.8 kWhMar 294.8 kWhDec 175.2 kWhDec 175.2 kWhMay 265.2 kWhMay 265.2 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.

Data Sources

This report illustrates the typical weather at Imperatriz, 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

Imperatriz has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required.

There are no other weather stations in our network within 200 kilometers of this location. Consequently, in the case of missing or erroneous measurements from this station, we fall back on NASA's MERRA-2 modern-era reanalysis , adjusted according to typical seasonal and diurnal differences between this station and the wide-area MERRA-2 reconstructed values.

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 © 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.