GoodSeeing
Home › Locations › Chillán Viejo

Chillán Viejo

-36.623° S   72.132° W  ·  117 M
54 /100
PEAK
Marginal, but there is a 4 hours gap from 01:00.
BEST WINDOW 01:00–05:00 · ASTRO DARK 20:00–07:00 · MOON 0%
Transparency
0.57
Seeing
1.00
Cloud
31%
Moon
0%

Fair tonight

Hour by hour, local to Chillán Viejo. Colour encodes the score and nothing else; every other measurement is luminance.

Sky state
Lighter = daylight and twilight  ·  unshaded = astronomical dark
Score
18
19
20
21
22
23
00
01
02
03
04
05
06
07
08
0
20
32
17
12
12
32
39
54
45
41
28
21
2
0
BEST WINDOW
Low cloud
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
4%
8%
Mid cloud
5%
22%
32%
60%
82%
88%
31%
40%
23%
7%
20%
52%
48%
46%
82%
High cloud
37%
15%
78%
93%
71%
49%
75%
31%
10%
57%
52%
44%
84%
100%
90%
Transparency
0.66
0.57
0.49
0.47
0.48
0.46
0.40
0.36
0.32
0.26
0.24
0.22
0.22
0.21
0.24
Seeing
1.00
1.00
0.99
0.94
0.91
0.96
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
Moon clear
0%
down
down
down
down
down
down
down
down
down
down
down
down
down
down
Inspect

Cloud tracks show clear sky — a longer bar is better. The figure inside each track is the raw measurement.

Why this hour scored what it did
18 Clouded out · 0/100
Starting from
100
Cloud
−24
Transparency
−11
Seeing
−0
Moonlight
−0
Darkness
−66
Score
0
CLOUD 38% LOW 0% MID 5% HIGH 37% SUN 1.6° MOON 4.7° / 0% WIND 1 TEMP 10°
Excellent 75+ Good 55+ Fair 35+ Poor 15+ Not worth it Seeing is estimated from surface wind — see how we score.

What are you doing tonight?

The same forecast, weighted for the target. Planetary work barely cares about moonlight; long exposures die on high cloud a visual observer would never notice.

SET UP 00:30 · OBSERVE 01:00–05:00 · 4H · MEAN 44

Darkness and moonlight dominate. Faint fuzzies need a genuinely dark sky more than they need steady air.

1820220002040608
HIGH CLOUD CLEARS 01:00
SET UP 23:30 · OBSERVE 00:00–05:00 · 5H · MEAN 50

Seeing is everything and moonlight is irrelevant. Bright targets punch through twilight, so darkness barely counts.

1820220002040608
MOONLIGHT IGNORED FOR THIS TARGET
SET UP 01:30 · OBSERVE 02:00–04:00 · 2H · MEAN 42

Tolerates soft seeing, but high cloud wrecks a wide frame and moonlight raises the background everywhere.

1820220002040608
HIGH CLOUD CLEARS 02:00
SET UP 01:30 · OBSERVE 02:00–03:00 · 1H · MEAN 38

Needs conditions to hold still for hours. Sustained transparency matters more than any single good hour.

1820220002040608
HIGH CLOUD CLEARS 02:00CLOUD RETURNS 03:00
SET UP 00:30 · OBSERVE 01:00–05:00 · 4H · MEAN 42

Naked eye, whole sky. Total cloud and moonlight are the only things that count.

1820220002040608
HIGH CLOUD CLEARS 01:00
Advertisement
Reserved

The next week of nights

Tonight · 12 Aug
54
Fair
MOON 0%
01:00–05:00
Tomorrow · 13 Aug
30
Poor
MOON 3%
Friday · 14 Aug
23
Poor
MOON 7%
Saturday · 15 Aug
36
Fair
MOON 15%
20:00–21:00
Sunday · 16 Aug
57
Good
MOON 23%
02:00–03:00
Monday · 17 Aug
72
Good
MOON 32%
02:00–03:00
Tuesday · 18 Aug
52
Fair
MOON 42%
20:00–21:00
Advertisement
Reserved

Nearby locations

About this forecast

Conditions for Chillán Viejo, Chile are computed from the MET Norway forecast model for these exact coordinates, combined with sun and moon positions we calculate directly. The score weighs cloud cover by layer, atmospheric transparency, estimated seeing, moonlight and how dark the sky actually gets. Read the full method →