14.3 usable nights
11–17 in the middle half of years · 5.0 typically near a dark moon.
341 astronomical-dark hours in an average month
20-year trip-planning baseline
When to plan an observing trip to Hemet
June: 23.8 usable nights on average. A regional planning baseline, not a forecast for your trip.
Site darkness · modelled, not measured
Bright skyBortle classes describe observed sky conditions; this brightness model does not establish a measured Bortle class.19.0–19.7 mag/arcsec²
The short answer
June has been strongest.
It averages 23.8 usable nights, versus 12.8 in February. A typical June lands between 22 and 28 usable nights.
Record2005–2024 · 20 complete years
Usable nightAt least 3 astronomical-dark hours and NASA POWER nighttime cloud ≤30%
Dark-moon nightUsable night with ≤25% illumination at local solar midnight
ResolutionCERES SYN1deg 1° cloud grid; regional climate, not a campsite guarantee
Seasonal fingerprint
Usable nights by month
Month by month
12.8 usable nights
9–17 in the middle half of years · 4.2 typically near a dark moon.
286 astronomical-dark hours in an average month
12.9 usable nights
8–17 in the middle half of years · 3.7 typically near a dark moon.
288 astronomical-dark hours in an average month
15.7 usable nights
13–17 in the middle half of years · 5.2 typically near a dark moon.
240 astronomical-dark hours in an average month
17.3 usable nights
14–22 in the middle half of years · 6.3 typically near a dark moon.
208 astronomical-dark hours in an average month
23.8 usable nights
22–28 in the middle half of years · 7.5 typically near a dark moon.
180 astronomical-dark hours in an average month
19.4 usable nights
17–22 in the middle half of years · 6.0 typically near a dark moon.
193 astronomical-dark hours in an average month
22.9 usable nights
21–24 in the middle half of years · 7.0 typically near a dark moon.
243 astronomical-dark hours in an average month
23.5 usable nights
22–26 in the middle half of years · 8.3 typically near a dark moon.
257 astronomical-dark hours in an average month
22.1 usable nights
20–25 in the middle half of years · 7.6 typically near a dark moon.
310 astronomical-dark hours in an average month
17.4 usable nights
16–19 in the middle half of years · 6.0 typically near a dark moon.
326 astronomical-dark hours in an average month
13.8 usable nights
10–16 in the middle half of years · 5.0 typically near a dark moon.
353 astronomical-dark hours in an average month
Use the baseline honestly
Climate chooses the month. Forecasts choose the night.
The cloud product is a roughly 1° regional grid. It can reveal seasonality, but it cannot know a mountain ridge, valley fog pocket, locked gate, smoke event or the exact sky you will get.
Source: NASA POWER daily data, parameter CLOUD_AMT_NIGHT from the CERES SYN1deg cloud product. GoodSeeing calculates astronomical darkness and lunar illumination independently for each place.