14.1 usable nights
11–17 in the middle half of years · 5.2 typically near a dark moon.
341 astronomical-dark hours in an average month
20-year trip-planning baseline
Best time to stargaze at Blythe
May: 23.6 usable nights on average. Use this seasonal climate baseline to choose a month, then use the live forecast to choose a night.
Site darkness · modelled, not measured
Brightened skyBortle classes describe observed sky conditions; this brightness model does not establish a measured Bortle class.20.4–20.9 mag/arcsec²
The short answer
May has been strongest.
It averages 23.6 usable nights, versus 13.7 in July. A typical May lands between 22 and 26 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
13.8 usable nights
9–17 in the middle half of years · 4.0 typically near a dark moon.
286 astronomical-dark hours in an average month
16.1 usable nights
14–19 in the middle half of years · 5.2 typically near a dark moon.
288 astronomical-dark hours in an average month
20.1 usable nights
19–22 in the middle half of years · 6.3 typically near a dark moon.
240 astronomical-dark hours in an average month
23.6 usable nights
22–26 in the middle half of years · 7.8 typically near a dark moon.
209 astronomical-dark hours in an average month
23.0 usable nights
21–26 in the middle half of years · 7.5 typically near a dark moon.
180 astronomical-dark hours in an average month
13.7 usable nights
11–15 in the middle half of years · 5.0 typically near a dark moon.
193 astronomical-dark hours in an average month
15.6 usable nights
12–18 in the middle half of years · 4.5 typically near a dark moon.
243 astronomical-dark hours in an average month
22.1 usable nights
20–24 in the middle half of years · 8.1 typically near a dark moon.
258 astronomical-dark hours in an average month
23.4 usable nights
21–27 in the middle half of years · 8.0 typically near a dark moon.
310 astronomical-dark hours in an average month
18.5 usable nights
17–21 in the middle half of years · 6.2 typically near a dark moon.
326 astronomical-dark hours in an average month
14.2 usable nights
11–17 in the middle half of years · 5.1 typically near a dark moon.
352 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.