12.0 usable nights
10–16 in the middle half of years · 3.9 typically near a dark moon.
310 astronomical-dark hours in an average month
20-year trip-planning baseline
Best time to stargaze at Fort Myers
March: 15.7 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
Bright skyBortle classes describe observed sky conditions; this brightness model does not establish a measured Bortle class.18.9–19.6 mag/arcsec²
The short answer
March has been strongest.
It averages 15.7 usable nights, versus 4.3 in July. A typical March lands between 13 and 20 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
13.6 usable nights
12–15 in the middle half of years · 4.5 typically near a dark moon.
283 astronomical-dark hours in an average month
15.7 usable nights
13–20 in the middle half of years · 5.5 typically near a dark moon.
300 astronomical-dark hours in an average month
13.9 usable nights
11–16 in the middle half of years · 4.3 typically near a dark moon.
244 astronomical-dark hours in an average month
14.1 usable nights
11–18 in the middle half of years · 4.4 typically near a dark moon.
248 astronomical-dark hours in an average month
5.5 usable nights
2–8 in the middle half of years · 1.9 typically near a dark moon.
240 astronomical-dark hours in an average month
4.3 usable nights
2–7 in the middle half of years · 1.6 typically near a dark moon.
248 astronomical-dark hours in an average month
4.6 usable nights
1–7 in the middle half of years · 1.4 typically near a dark moon.
248 astronomical-dark hours in an average month
6.4 usable nights
3–9 in the middle half of years · 1.8 typically near a dark moon.
274 astronomical-dark hours in an average month
13.9 usable nights
12–16 in the middle half of years · 4.6 typically near a dark moon.
310 astronomical-dark hours in an average month
15.7 usable nights
13–19 in the middle half of years · 5.2 typically near a dark moon.
313 astronomical-dark hours in an average month
14.4 usable nights
12–18 in the middle half of years · 4.8 typically near a dark moon.
315 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.