What humidity is best for stargazing in Guyana?

Lower humidity and a wider temperature-to-dew-point spread reduce fog and dew risk. Tropical nights can still be usable, but saturated air often softens stars and wets optics faster than dry climates. This tool scores dew risk and prefers drier hours for the best window.

What does transparency mean here?

Transparency is estimated from CAMS aerosol optical depth via Open-Meteo’s open Air Quality API. It describes haze, not telescope seeing (arcsecond FWHM). Low AOD means a clearer line of sight.

Is this a replacement for a general weather app?

No — it filters forecast data for astronomy: cloud layer trends, humidity/dew risk, transparency, and when a usable dark window might open. Pair it with the Dark Sky Window tool for moonless darkness timing.

How far ahead should I check?

The 7-night outlook is for planning; treat tonight and tomorrow as the most reliable. Tropical convection can change quickly — refresh before you leave.

Tools

Is the Sky Clear Tonight? Free Forecast

Is tonight good for stargazing? Hourly cloud layers, dew risk, transparency, and a Go / Maybe / Skip score — so you know if tonight is worth the drive.

Georgetown

6.8000°N, 58.1700°W

Drizzle

Go tonight — solid window, dew is a concern

Georgetown·6.8000, -58.1700

Tonight

2% cloud
watch dew
transparency good
4.0h astro dark
moon 28% lit
clear window soon

Transparency · good · AOD 0.15Dew risk · low · Δ 6.4°C

Best viewing now

19:00–06:00 · excellent · 2% cloud · 84% RH

Prefers clear, drier night hours inside astronomical darkness when available.

Current conditions

Cloud Cover

23%

Visibility

8 km

Humidity

69%

Dew spread

6.4°C · Low dew risk

Temp

30°C

Wind

13 km/h

Cloud layers · Next 24h

Tonight avg 4%

LowMidHighAstro darkBest windowStack = low / mid / high cloud %

7-night outlook

Score · cloud · dew · dark

Best night this week: Tonight · 75 (Go)

Tonight · best
75Go
2% cloud
84% · moderate dew
4h dark
Tomorrow
62Maybe
33% cloud
88% · moderate dew
3h dark
Wed
66Maybe
11% cloud
87% · moderate dew
2h dark
Thu
51Maybe
41% cloud
87% · moderate dew
1h dark
Fri
53Maybe
28% cloud
87% · moderate dew
No astro dark
Sat
26Skip
88% cloud
86% · moderate dew
No astro dark
Sun
25Skip
89% cloud
84% · moderate dew
No astro dark

Weather by Open-Meteo (CC BY 4.0). Transparency uses CAMS aerosol optical depth via Open-Meteo Air Quality — not telescope seeing (arcseconds).

Frequently asked questions

What humidity is best for stargazing in Guyana?: Lower humidity and a wider temperature-to-dew-point spread reduce fog and dew risk. Tropical nights can still be usable, but saturated air often softens stars and wets optics faster than dry climates. This tool scores dew risk and prefers drier hours for the best window.
What does transparency mean here?: Transparency is estimated from CAMS aerosol optical depth via Open-Meteo’s open Air Quality API. It describes haze, not telescope seeing (arcsecond FWHM). Low AOD means a clearer line of sight.
Is this a replacement for a general weather app?: No — it filters forecast data for astronomy: cloud layer trends, humidity/dew risk, transparency, and when a usable dark window might open. Pair it with the Dark Sky Window tool for moonless darkness timing.
How far ahead should I check?: The 7-night outlook is for planning; treat tonight and tomorrow as the most reliable. Tropical convection can change quickly — refresh before you leave.

Forecast and air-quality data by Open-Meteo (CC BY 4.0); aerosol fields from CAMS. Next: check your Bortle class, confirm moonless hours, then see what’s in the sky.