Climate and average weather in Lethem
In Lethem, the weather is muggy, hot, wet, and partly cloudy and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around May.
Over the course of the year, the temperature in Lethem typically varies from 22°C to 32°C, and is rarely below 21°C or above 34°C. October is the hottest month of the year, while July is the coldest.
Based on the travel score, the best times of year to visit Lethem for warm-weather activities are from early January to mid April and late November to late December.
- Hottest
- Oct
- 32°
- Coldest
- Jul
- 22°
- Wettest
- May
- 386 mm
- Driest
- Jan
- 46 mm
- Rain / yr
- 2181 mm
- 218 wet days
- Daylight
- 11.8–12.2 h
- shortest–longest
- Elevation
- 0 m
- 3.4°N
- Clearest
- Sep
- 57% cloud
Lethem is Regional Capital of Alto Tcutu-Upper Essequibo, which is controlled by Guyana and claimed by Venezuela.
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Lethem weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early January to mid April.
Temperature through the year
Daily average highs and lows in Lethem, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
Temperatures in Lethem stay fairly even through the year, without a distinct hot or cool season. The warmest month is October, with an average high of 32°C and low of 23°C; the coolest is July, with an average low of 22°C and high of 29°C.
Days typically run about 8°C warmer than nights year-round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 31 | 31 | 32 | 31 | 29 | 29 | 29 | 30 | 31 | 32 | 32 | 31 |
| Avg low (°C) | 22 | 22 | 23 | 23 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 31 | 22 |
| Feb | 31 | 22 |
| Mar | 32 | 23 |
| Apr | 31 | 23 |
| May | 29 | 22 |
| Jun | 29 | 22 |
| Jul | 29 | 22 |
| Aug | 30 | 22 |
| Sep | 31 | 23 |
| Oct | 32 | 23 |
| Nov | 32 | 23 |
| Dec | 31 | 23 |
How hot and cold Lethem really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the hottest afternoons, once humidity is folded in, Lethem feels like about 36°C (around October 26). About 314 days a year carry some heat stress, peaking in October.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 33 | 33 | 33 | 34 | 32 | 32 | 32 | 33 | 35 | 36 | 35 | 34 |
| Air high (°C) | 31 | 31 | 32 | 31 | 29 | 29 | 29 | 30 | 31 | 32 | 32 | 31 |
| Feels-like low (°C) | 22 | 22 | 23 | 23 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 |
| Air low (°C) | 22 | 22 | 23 | 23 | 22 | 22 | 22 | 22 | 23 | 23 | 23 | 23 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 33 | 31 | 22 | 22 |
| Feb | 33 | 31 | 22 | 22 |
| Mar | 33 | 32 | 23 | 23 |
| Apr | 34 | 31 | 23 | 23 |
| May | 32 | 29 | 22 | 22 |
| Jun | 32 | 29 | 22 | 22 |
| Jul | 32 | 29 | 22 | 22 |
| Aug | 33 | 30 | 22 | 22 |
| Sep | 35 | 31 | 23 | 23 |
| Oct | 36 | 32 | 23 | 23 |
| Nov | 35 | 32 | 23 | 23 |
| Dec | 34 | 31 | 23 | 23 |
Average hourly temperature in Lethem
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on October afternoons, near 32°C, and coldest before dawn in July, near 22°C.
Lethem weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 31° / 22° | 46 | 9.3 | 11.8 | 4.6 |
| Feb | 31° / 22° | 47 | 8.2 | 11.9 | 4.5 |
| Mar | 32° / 23° | 64 | 9.3 | 12 | 4.1 |
| Apr | 31° / 23° | 188 | 17.1 | 12.1 | 3.6 |
| May | 29° / 22° | 386 | 27 | 12.2 | 3.2 |
| Jun | 29° / 22° | 367 | 28.4 | 12.2 | 3.1 |
| Jul | 29° / 22° | 363 | 28.9 | 12.2 | 3.2 |
| Aug | 30° / 22° | 261 | 25.4 | 12.1 | 3.3 |
| Sep | 31° / 23° | 157 | 18.8 | 12 | 3.5 |
| Oct | 32° / 23° | 115 | 16.4 | 11.9 | 3.5 |
| Nov | 32° / 23° | 114 | 15.6 | 11.8 | 3.5 |
| Dec | 31° / 23° | 75 | 13.6 | 11.8 | 4.1 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Lethem gets about 2181 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.
The wetter season lasts 5.1 months, from around Apr 17 to Sep 19, peaking in June at about 95% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Mar 1.
May is the wettest month by volume, with 386 mm over about 27 wet days; January is the driest, with 46 mm.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 30 | 29 | 31 | 58 | 86 | 94 | 93 | 82 | 63 | 53 | 52 | 43 |
| Rain days | 9 | 8 | 9 | 17 | 27 | 28 | 29 | 25 | 19 | 16 | 16 | 14 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 30 | 9 |
| Feb | 29 | 8 |
| Mar | 31 | 9 |
| Apr | 58 | 17 |
| May | 86 | 27 |
| Jun | 94 | 28 |
| Jul | 93 | 29 |
| Aug | 82 | 25 |
| Sep | 63 | 19 |
| Oct | 53 | 16 |
| Nov | 52 | 16 |
| Dec | 43 | 14 |
Monthly rainfall
Over a full year, Lethem collects about 2181 mm of rain across 218 wet days — roughly 182 mm in an average month.
It doesn’t fall evenly. May is the wettest month with 386 mm, while January is the driest at just 46 mm. The three wettest months alone bring about 51% of the year’s total.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 46 | 47 | 64 | 188 | 386 | 367 | 363 | 261 | 157 | 115 | 114 | 75 |
| Rain days | 9 | 8 | 9 | 17 | 27 | 28 | 29 | 25 | 19 | 16 | 16 | 14 |
| Rainfall (mm) | Rain days | |
|---|---|---|
| Jan | 46 | 9 |
| Feb | 47 | 8 |
| Mar | 64 | 9 |
| Apr | 188 | 17 |
| May | 386 | 27 |
| Jun | 367 | 28 |
| Jul | 363 | 29 |
| Aug | 261 | 25 |
| Sep | 157 | 19 |
| Oct | 115 | 16 |
| Nov | 114 | 16 |
| Dec | 75 | 14 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Lethem, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.
The clearer part of the year begins around August 7 and lasts for 5.5 months, ending around January 21. The clearest month is September, when the sky is clear, mostly clear, or partly cloudy 57% of the time on average.
The cloudier part of the year begins around January 22 and lasts for 6.5 months, ending around August 6. The cloudiest month is May, when it is overcast or mostly cloudy 89% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 35 | 31 | 31 | 21 | 11 | 18 | 25 | 41 | 57 | 52 | 40 | 37 |
| Cloudier (%) | 65 | 69 | 69 | 79 | 89 | 82 | 75 | 59 | 43 | 48 | 60 | 63 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 35 | 65 |
| Feb | 31 | 69 |
| Mar | 31 | 69 |
| Apr | 21 | 79 |
| May | 11 | 89 |
| Jun | 18 | 82 |
| Jul | 25 | 75 |
| Aug | 41 | 59 |
| Sep | 57 | 43 |
| Oct | 52 | 48 |
| Nov | 40 | 60 |
| Dec | 37 | 63 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. Close to the equator, Lethem barely changes through the year: days stay near 12 h 12 min of light in every season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 11.8 | 11.9 | 12.0 | 12.1 | 12.2 | 12.2 | 12.2 | 12.1 | 12.0 | 11.9 | 11.8 | 11.8 |
| Sunrise (AM) | 6:14 | 6:17 | 6:10 | 5:57 | 5:51 | 5:54 | 5:59 | 6:00 | 5:53 | 5:46 | 5:49 | 6:01 |
| Sunset (PM) | 6:03 | 6:11 | 6:08 | 6:02 | 6:00 | 6:05 | 6:10 | 6:07 | 5:54 | 5:42 | 5:40 | 5:50 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 11.8 | 6:14 | 6:03 |
| Feb | 11.9 | 6:17 | 6:11 |
| Mar | 12.0 | 6:10 | 6:08 |
| Apr | 12.1 | 5:57 | 6:02 |
| May | 12.2 | 5:51 | 6:00 |
| Jun | 12.2 | 5:54 | 6:05 |
| Jul | 12.2 | 5:59 | 6:10 |
| Aug | 12.1 | 6:00 | 6:07 |
| Sep | 12.0 | 5:53 | 5:54 |
| Oct | 11.9 | 5:46 | 5:42 |
| Nov | 11.8 | 5:49 | 5:40 |
| Dec | 11.8 | 6:01 | 5:50 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Lethem averages about 4 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 10 days.
The sunnier stretch runs 3.9 months, from around Aug 10 to Dec 6. The sunniest month is September, with roughly 9 sunny days (mixed).
The greyest month is June, down near 1 sunny days — about 89% fewer than the September peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 3 | 2 | 3 | 2 | 1 | 1 | 2 | 5 | 9 | 8 | 5 | 3 |
| Sky | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Mixed | Mixed | Gloomy | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 3 | Gloomy |
| Feb | 2 | Gloomy |
| Mar | 3 | Gloomy |
| Apr | 2 | Gloomy |
| May | 1 | Gloomy |
| Jun | 1 | Gloomy |
| Jul | 2 | Gloomy |
| Aug | 5 | Gloomy |
| Sep | 9 | Mixed |
| Oct | 8 | Mixed |
| Nov | 5 | Gloomy |
| Dec | 3 | Gloomy |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
Lethem is humid all year round — on a typical day the air feels at least humid, and there is no real dry season to wait for.
The stickiest month is January, when it feels muggy, oppressive or miserable about 89% of the time. Even in February, the mildest month, the air is dry or comfortable only 1% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Comfortable (%) | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Humid (%) | 11 | 17 | 16 | 6 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 2 |
| Muggy (%) | 66 | 63 | 60 | 34 | 12 | 2 | 2 | 2 | 10 | 22 | 24 | 43 |
| Oppressive (%) | 24 | 19 | 24 | 59 | 88 | 98 | 98 | 98 | 90 | 77 | 76 | 55 |
| Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | |
|---|---|---|---|---|
| Jan | 0 | 11 | 66 | 24 |
| Feb | 1 | 17 | 63 | 19 |
| Mar | 0 | 16 | 60 | 24 |
| Apr | 0 | 6 | 34 | 59 |
| May | 0 | 0 | 12 | 88 |
| Jun | 0 | 0 | 2 | 98 |
| Jul | 0 | 0 | 2 | 98 |
| Aug | 0 | 0 | 2 | 98 |
| Sep | 0 | 0 | 10 | 90 |
| Oct | 0 | 1 | 22 | 77 |
| Nov | 0 | 0 | 24 | 76 |
| Dec | 0 | 2 | 43 | 55 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Lethem is typically calm, near 9 km/h, and varies moderately with the seasons.
The windier part of the year lasts 5.1 months, from around Nov 21 to Apr 25. The windiest month is February, averaging about 13 km/h (light breeze).
The calmer part of the year runs from around Apr 26 to Nov 20, with July the calmest month at about 5 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 13 | 13 | 13 | 10 | 8 | 6 | 5 | 6 | 7 | 8 | 9 | 11 |
| Feels | light breeze | light breeze | light breeze | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 13 | light breeze |
| Feb | 13 | light breeze |
| Mar | 13 | light breeze |
| Apr | 10 | calm |
| May | 8 | calm |
| Jun | 6 | calm |
| Jul | 5 | calm |
| Aug | 6 | calm |
| Sep | 7 | calm |
| Oct | 8 | calm |
| Nov | 9 | calm |
| Dec | 11 | calm |
Hazard calendar for Lethem
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Lethem's monsoon runs April–August, when most of the year's rain falls.
Best time to visit Lethem
To characterize how pleasant the weather is in Lethem throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around early April, Lethem is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Lethem for general outdoor tourist activities is from late November to mid April, with a peak score in the second week of January.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 4.6 | 4.5 | 4.1 | 3.6 | 3.2 | 3.1 | 3.2 | 3.3 | 3.5 | 3.5 | 3.5 | 4.1 |
| Rating | fair | fair | fair | fair | poor | poor | poor | poor | fair | poor | fair | fair |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 4.6 | fair |
| Feb | 4.5 | fair |
| Mar | 4.1 | fair |
| Apr | 3.6 | fair |
| May | 3.2 | poor |
| Jun | 3.1 | poor |
| Jul | 3.2 | poor |
| Aug | 3.3 | poor |
| Sep | 3.5 | fair |
| Oct | 3.5 | poor |
| Nov | 3.5 | fair |
| Dec | 4.1 | fair |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Lethem for hot-weather activities is from mid September to mid April, with a peak score in the third week of January.
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).
What to pack for Lethem, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
Lethem packs about the same all year — highs hold near 32°C. Across the year the things worth having are light clothes, rain gear and sun protection.
In October, Lethem sees daytime highs around 32°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 16 days see rain.
UV index (midday) in Lethem by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Lethem peaks around March 21 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 16 at about 11 (extreme).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 14 | 14 | 15 | 15 | 13 | 12 | 11 | 12 | 12 | 12 | 11 | 11 |
| Level | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 14 | Extreme |
| Mar | 15 | Extreme |
| Apr | 15 | Extreme |
| May | 13 | Extreme |
| Jun | 12 | Extreme |
| Jul | 11 | Extreme |
| Aug | 12 | Extreme |
| Sep | 12 | Extreme |
| Oct | 12 | Extreme |
| Nov | 11 | Extreme |
| Dec | 11 | Extreme |
Average hourly UV index in Lethem
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in March the burn window is concentrated in the middle of the day: about 8 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 8 | 8 | 8 | 8.5 | 8 | 8 | 7.5 | 8 | 8 | 8 | 7.5 | 7.5 |
| UV ≥ 6 (h/day) | 6 | 6.5 | 6.5 | 6.5 | 6 | 6 | 5.5 | 6 | 6 | 6 | 5.5 | 5.5 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 8 | 6 |
| Feb | 8 | 6.5 |
| Mar | 8 | 6.5 |
| Apr | 8.5 | 6.5 |
| May | 8 | 6 |
| Jun | 8 | 6 |
| Jul | 7.5 | 5.5 |
| Aug | 8 | 6 |
| Sep | 8 | 6 |
| Oct | 8 | 6 |
| Nov | 7.5 | 5.5 |
| Dec | 7.5 | 5.5 |
Air quality in Lethem by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Lethem is worst in April — around 20 µg/m³ PM2.5 (moderate), about 1.9× the cleanest month (August, 10 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 15 | 18 | 20 | 20 | 14 | 12 | 11 | 10 | 11 | 12 | 12 | 13 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 18 | Moderate |
| Mar | 20 | Moderate |
| Apr | 20 | Moderate |
| May | 14 | Moderate |
| Jun | 12 | Moderate |
| Jul | 11 | Good |
| Aug | 10 | Good |
| Sep | 11 | Good |
| Oct | 12 | Good |
| Nov | 12 | Moderate |
| Dec | 13 | Moderate |
Growing season
Lethem is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
| Frost nights | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Lethem banks about 6,005 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around October.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 512 | 464 | 531 | 506 | 491 | 458 | 468 | 491 | 505 | 540 | 520 | 520 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 512 |
| Feb | 464 |
| Mar | 531 |
| Apr | 506 |
| May | 491 |
| Jun | 458 |
| Jul | 468 |
| Aug | 491 |
| Sep | 505 |
| Oct | 540 |
| Nov | 520 |
| Dec | 520 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Lethem receives about 4.9 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.8 and 5.8 kWh/m².
The brighter stretch of the year lasts 4.0 months, from around Aug 17 to Dec 15. The brightest month is October, averaging about 5.7 kWh/m² (bright).
The dimmest month is June, down near 3.9 kWh/m² — roughly 33% less than the October peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 5.0 | 5.1 | 5.4 | 4.8 | 3.8 | 3.8 | 4.2 | 4.9 | 5.6 | 5.7 | 5.3 | 4.9 |
| Level | Bright | Bright | Bright | Bright | Moderate | Moderate | Bright | Bright | Bright | Bright | Bright | Bright |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 5.0 | Bright |
| Feb | 5.1 | Bright |
| Mar | 5.4 | Bright |
| Apr | 4.8 | Bright |
| May | 3.8 | Moderate |
| Jun | 3.8 | Moderate |
| Jul | 4.2 | Bright |
| Aug | 4.9 | Bright |
| Sep | 5.6 | Bright |
| Oct | 5.7 | Bright |
| Nov | 5.3 | Bright |
| Dec | 4.9 | Bright |
Where is Lethem?
Lethem sits at 3.4°N, 59.8°W, 0 m above sea level, in Guyana. The nearest listed city is Boa Vista, 115 km away.
Topography around Lethem
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Lethem.
Within 3 km, the terrain around Lethem has only modest variations in elevation — a maximum elevation change of 23 m around an average of 87 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 832 m; within 80 km, large variations in elevation — a maximum elevation change of 1,000 m.
The land around Lethem is covered by grassland (79%) within 3 km, grassland (85%) within 16 km, and grassland (68%) and trees (30%) within 80 km.
Guyana travel facts
- Travel advisory
- Level 3
- Reconsider Travel
- Power plugs
- Type A / B / D / G
- 240 V · 60 Hz
- Prices
- ≈ 33% of US
- price level, 2025
- GDP per capita
- $32,414
- 2025
- Happiness
- 6.0 / 10
- World Happiness, 2011
- Safe drinking water
- 67%
- of population, 2024
- Homicide rate
- 19.1
- per 100k, 2023
- Road deaths
- 22.3
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Lethem (3.3726°, -59.7997°, elevation 0 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).