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Night Forecast

Weather
Observing Conditions.

Hour-by-hour night-window forecast built for observing, imaging, and planning around clouds, rain risk, visibility, dew spread, wind, humidity, and your active rig.

Good conditions
Observing Outlook

Good observing conditions expected

Night-window score reflects clouds, rain risk, visibility, dew risk, wind, and humidity. Clouds 3%, rain risk 17%, wind 6 mph.

75/100 Good Best: 3 AM – 6 AM
Choose Forecast Date
Su M T W Th F Sa
16 17 18 19 20 21 22 23 24 25 26 27 28 29
Forecast Location Chicago Area 41.878100, -87.629800 41.87810, -87.62980
Overall 75 Good
Clouds 3% Clear
Rain Risk 17% Max overnight
Visibility 11.8 mi Fair
Wind 6 mph Gusts 17 mph
Observatory Intelligence

No default rig selected

Add your telescope, focal length, and mount to unlock equipment-specific weather guidance.

Ephemeris can interpret wind, cloud layers, humidity, and dew risk differently for widefield, mid-focal, and long-focal-length setups.

Best Use Tonight General observing guidance
Avoid Tonight Rig-specific guidance unavailable
Improves After 2 AM
•
Visual Observing

General sky conditions are available now.

What makes an observing forecast different? →
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Deep Sky Imaging

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Why does rig data matter for imaging? →
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Planetary / Lunar

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Why does focal length change weather sensitivity? →
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Forecast Confidence

Moderate Confidence

The forecast is usable, but cloud timing or moisture may change the practical observing window.

3 forecast source active
  • Forecast sources active: 2
  • Alert sources active: 1
  • Forecast models disagree during multiple observing hours
  • Cloud cover changes sharply during the night
Hour-by-Hour

Observing Window

2026-08-26 7 PM → next morning 6 AM
Time Score Outlook Clouds Low Mid High Rain Visibility Dew Spread Wind Humidity
8/26 - 7 PM 77 Good 15% 14% 0% 0% 16% 15 mi 11.5°F ? 9 mph 68%
8/26 - 8 PM 77 Good 12% 11% 0% 0% 17% 10.7 mi 8.9°F ? 8 mph 74%
8/26 - 9 PM 75 Good 5% 5% 0% 0% 17% 6.3 mi 5.9°F ? 7 mph 82%
8/26 - 10 PM 67 Good 0% 0% 0% 0% 17% 2 mi 3.8°F ? 7 mph 88%
8/26 - 11 PM 70 Good 0% 0% 0% 0% 17% 6.3 mi 2.5°F ? 6 mph 92%
8/27 - 12 AM 74 Good 0% 0% 0% 0% 17% 10.7 mi 1.8°F ? 6 mph 94%
8/27 - 1 AM 74 Good 0% 0% 0% 0% 17% 15 mi 1.5°F ? 6 mph 95%
8/27 - 2 AM 78 Good 0% 0% 0% 0% 9% 15 mi 1.4°F ? 6 mph 95%
8/27 - 3 AM 78 Good 0% 0% 0% 0% 9% 15 mi 1.5°F ? 5 mph 95%
8/27 - 4 AM 78 Good 0% 0% 0% 0% 9% 15 mi 1.8°F ? 5 mph 94%
8/27 - 5 AM 78 Good 0% 0% 0% 0% 9% 15 mi 1.8°F ? 5 mph 94%
8/27 - 6 AM 78 Good 0% 0% 0% 0% 9% 15 mi 1.8°F ? 5 mph 94%
Cloud Timeline

Cloud Cover by Hour

Each hour shows total cloud cover plus the split between low, mid, and high cloud layers.

Low Mid High
7 PM
15% Total
Low
14%
Mid
0%
High
0%
8 PM
12% Total
Low
11%
Mid
0%
High
0%
9 PM
5% Total
Low
5%
Mid
0%
High
0%
10 PM
0% Total
Low
0%
Mid
0%
High
0%
11 PM
0% Total
Low
0%
Mid
0%
High
0%
12 AM
0% Total
Low
0%
Mid
0%
High
0%
1 AM
0% Total
Low
0%
Mid
0%
High
0%
2 AM
0% Total
Low
0%
Mid
0%
High
0%
3 AM
0% Total
Low
0%
Mid
0%
High
0%
4 AM
0% Total
Low
0%
Mid
0%
High
0%
5 AM
0% Total
Low
0%
Mid
0%
High
0%
6 AM
0% Total
Low
0%
Mid
0%
High
0%
Why this score?

Limiting Factors

Humidity 89% Major limiter
Dew Spread 3.7°F Major limiter
Visibility 11.8 mi High impact
Precipitation 17% max Low impact
Wind 6 mph Low impact
Source Comparison

Forecast Sources

MVP starts with Open-Meteo; additional sources will improve confidence scoring.
Source Clouds Rain Humidity Wind Status
Open-Meteo 3% 17% 89% 6 mph Primary forecast
Tomorrow.io -- -- -- -- Secondary forecast active
National Weather Service -- -- -- -- No severe alert cap