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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 35%, rain risk 7%, wind 4 mph.

69/100 Good Best: 12 AM – 3 AM
Choose Forecast Date
Su M T W Th F Sa
4 5 6 7 8 9 10 11 12 13 14 15 16 17
Forecast Location Chicago Area 41.878100, -87.629800 41.87810, -87.62980
Overall 69 Good
Clouds 35% Mainly clear
Rain Risk 7% Max overnight
Visibility 15.0 mi Good
Wind 4 mph Gusts 11 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 12 AM
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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

2026-10-11 7 PM → next morning 6 AM
Time Score Outlook Clouds Low Mid High Rain Visibility Dew Spread Wind Humidity Temp
10/11 - 7 PM 25 Poor 100% 2% 98% 100% 6% 15.0 mi 8.4°F 3 mph 74% 63°F
10/11 - 8 PM 35 Poor 90% 2% 69% 90% 7% 15.0 mi 8.0°F 2 mph 75% 63°F
10/11 - 9 PM 50 Fair 76% 1% 29% 75% 7% 15.0 mi 8.0°F 1 mph 75% 62°F
10/11 - 10 PM 65 Good 60% 0% 0% 58% 7% 15.0 mi 8.1°F 1 mph 75% 62°F
10/11 - 11 PM 75 Good 41% 0% 0% 39% 7% 15.0 mi 8.0°F 2 mph 75% 62°F
10/12 - 12 AM 87 Excellent 19% 0% 0% 18% 7% 15.0 mi 8.4°F 4 mph 74% 63°F
10/12 - 1 AM 85 Excellent 4% 0% 0% 3% 7% 15.0 mi 8.4°F 5 mph 74% 63°F
10/12 - 2 AM 85 Excellent 0% 0% 0% 0% 6% 15.0 mi 8.1°F 5 mph 75% 62°F
10/12 - 3 AM 85 Excellent 0% 0% 0% 0% 6% 15.0 mi 7.3°F 5 mph 77% 62°F
10/12 - 4 AM 85 Excellent 0% 0% 0% 0% 6% 15.0 mi 6.6°F 4 mph 79% 62°F
10/12 - 5 AM 81 Excellent 7% 7% 0% 0% 6% 15.0 mi 5.9°F 5 mph 81% 61°F
10/12 - 6 AM 75 Good 18% 18% 0% 0% 6% 15.0 mi 4.9°F 7 mph 84% 60°F
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
100% Total
Low
2%
Mid
98%
High
100%
8 PM
90% Total
Low
2%
Mid
69%
High
90%
9 PM
76% Total
Low
1%
Mid
29%
High
75%
10 PM
60% Total
Low
0%
Mid
0%
High
58%
11 PM
41% Total
Low
0%
Mid
0%
High
39%
12 AM
19% Total
Low
0%
Mid
0%
High
18%
1 AM
4% Total
Low
0%
Mid
0%
High
3%
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
7% Total
Low
7%
Mid
0%
High
0%
6 AM
18% Total
Low
18%
Mid
0%
High
0%
Why this score?

Limiting Factors

Humidity 77% Major limiter
Dew Spread 7.5°F High impact
Visibility 15 mi Moderate impact
High Clouds 32% Moderate impact
Mid Clouds 16% 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 35% 7% 77% 4 mph Primary forecast
Tomorrow.io -- -- -- -- Secondary forecast active
National Weather Service -- -- -- -- Active alert cap: 20