Emigration Canyon Lookout
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Emigration Canyon Lookout clear sky chart from 2005-11-06 to 2026-08-15.

This page is a summary of past forecasts. Even though it's based only on forecasts, some people use these pages as clue to a site's climate. But climate data based on actual observation should be preferred (if you can find it!).

Cloud, Transparency and Seeing forecasts are summarized individually. But because good observing conditions require a combination of minimum cloud cover, transparency and seeing, the individual forecast summaries can be difficult to interpret. The observing conditions section counts the combinations of conditions needed for common types of astronomical observation.

Observing Conditions

The following tables count the occurrence of the combinations of forecast and darkness conditions needed for different observations. Conditions are rated by by what percentage of the hours the observation would likely be attempted are usable.

Observation Type	Minimum conditions for hour to be usable				Out of hours
	Clear of Clouds	Transparency	Seeing	Sky Brightness
Planetary:	50%	(no limit)	Average	(no limit)	Nighttime Hours
Deep Sky:	70%	Average	(no limit)	5.9	Nighttime Hours
CCD Imaging:	70%	Below Average	Poor	(no limit)	Nighttime Hours

Percentages are of nighttime hours per month, or per year, when a particular observing conditions was met. Deep Sky percentages never exceed 50% because the moon is up half the time. Deep sky percentages are much lower for charts at high latitudes because of fewer dark hours in the summer.

Overall

By Month

Individual Forecasts

The length of each colored bar in the "occurrence of each Forecast" column is proportional to the number of times the chart forecast that color. The percentages are of the total number of hours per month, or per year, with a particular forecast. The colors as the same as those used in clear sky charts.

Note: Transparency probabilities are only counted for those hours that have 30% or less cloud cover. Seeing probabilities are only counted for those hours that have 80% or less cloud cover. If that's too tricky, try Observing Conditions instead.

Overall

		Occurrence of each Forecast	Data Points
Cloud Cover	Day	4 9% 3 7% 4 4 4 3 5% 6% 51%	151982
	Night	4 9% 3 7% 4 4 4 3 5% 6% 50%	147498
Transparency	Day	29% 8% 11% 19% 21% 13%	146718
	Night	29% 8% 12% 20% 21% 11%	143769
Seeing	Day	13% 17% 33% 26% 9% 1	17471
	Night	12% 8% 24% 36% 18% 3	27816

By Month

Percentage Cloud Cover SW (2006-)
Color Meanings: Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	4 21% 9% 12% 6% 3 3 2 4 4 32%	5318
	11th to 20th	Day	3 12% 6% 16% 5% 3 3 2 3 4 45%	5340
	21st to end	Day	3 13% 5% 10% 3 3 3 2 4 6% 48%	5844
February	1st to 10th	Day	7% 20% 6% 11% 5% 4 3 3 4 5% 33%	1890
	11th to 20th	Day	7% 18% 6% 13% 6% 4 4 3 4 5% 30%	1908
	21st to end	Day	5% 19% 6% 15% 5% 3 4 4 4 6% 29%	1730
March	1st to 10th	Day	3 17% 10% 11% 4 5% 4 3 4 5% 34%	4947
	11th to 20th	Day	3 11% 7% 11% 4 4 4 4 6% 7% 40%	5110
	21st to end	Day	5% 23% 7% 11% 5% 5% 5% 3 4 4 28%	5607
April	1st to 10th	Day	7% 14% 5% 8% 4 4 5% 4 6% 6% 37%	2337
	11th to 20th	Day	7% 16% 4 8% 6% 5% 3 3 5% 6% 38%	2647
	21st to end	Day	7% 15% 4 6% 4 4 3 4 6% 7% 40%	2730
May	1st to 10th	Day	6% 10% 3 5% 4 4 4 4 6% 6% 47%	7626
	11th to 20th	Day	5% 10% 3 5% 4 4 4 3 5% 7% 50%	7596
	21st to end	Day	4 5% 2 6% 4 5% 5% 4 6% 7% 51%	8370
June	1st to 10th	Day	4 4 2 5% 4 4 4 4 6% 8% 55%	2856
	11th to 20th	Day	5% 4 2 4 3 3 3 3 4 6% 63%	2940
	21st to end	Day	2 2 1 4 3 3 3 3 4 5% 70%	2795
July	1st to 10th	Day	1 2 1 2 3 3 3 3 5% 7% 71%	7649
	11th to 20th	Day	2 2 1 4 3 4 5% 5% 7% 9% 59%	7650
	21st to end	Day	2 2 1 3 3 3 4 3 6% 7% 67%	8304
August	1st to 10th	Day	2 2 1 3 3 3 4 3 5% 5% 69%	5909
	11th to 20th	Day	2 2 1 3 3 3 3 3 5% 6% 70%	5851
	21st to end	Day	3 3 1 4 3 4 5% 4 7% 7% 60%	6407
September	1st to 10th	Day	3 3 1 3 2 2 3 3 5% 5% 68%	2270
	11th to 20th	Day	5% 4 1 4 3 4 4 4 5% 5% 62%	2200
	21st to end	Day	6% 4 1 4 3 3 4 2 4 6% 65%	2200
October	1st to 10th	Day	5% 5% 1 4 3 3 3 3 4 3 66%	3417
	11th to 20th	Day	8% 7% 1 3 2 2 4 3 4 7% 56%	3250
	21st to end	Day	5% 10% 3 6% 4 3 3 3 3 6% 54%	3533
November	1st to 10th	Day	7% 13% 3 6% 5% 3 5% 3 4 5% 46%	1854
	11th to 20th	Day	10% 12% 4 7% 4 4 3 3 4 6% 42%	1890
	21st to end	Day	5% 13% 5% 10% 5% 5% 4 3 4 5% 42%	1715
December	1st to 10th	Day	5% 9% 3 8% 3 2 2 3 3 6% 55%	2700
	11th to 20th	Day	6% 14% 8% 11% 5% 5% 4 4 6% 7% 30%	3106
	21st to end	Day	7% 16% 6% 13% 6% 6% 5% 4 6% 5% 29%	4486
January	1st to 10th	Night	5% 17% 8% 15% 4 4 3 3 4 5% 33%	7605
	11th to 20th	Night	4 14% 5% 11% 3 3 3 2 3 4 48%	7650
	21st to end	Night	2 10% 5% 8% 4 4 4 3 4 7% 49%	8370
February	1st to 10th	Night	6% 14% 6% 11% 5% 4 5% 4 5% 6% 35%	2730
	11th to 20th	Night	5% 16% 5% 12% 4 3 3 3 4 6% 37%	2594
	21st to end	Night	4 15% 5% 12% 5% 3 4 3 5% 6% 38%	2076
March	1st to 10th	Night	6% 15% 6% 11% 5% 4 4 4 5% 6% 35%	5165
	11th to 20th	Night	3 12% 5% 8% 5% 4 5% 4 7% 8% 38%	5110
	21st to end	Night	5% 19% 6% 8% 4 3 4 3 5% 5% 37%	5610
April	1st to 10th	Night	9% 13% 5% 6% 4 3 4 3 4 6% 45%	2282
	11th to 20th	Night	6% 12% 2 6% 4 4 4 4 6% 6% 44%	1917
	21st to end	Night	7% 11% 2 7% 6% 5% 4 3 5% 7% 43%	1890
May	1st to 10th	Night	5% 9% 3 5% 4 3 3 4 6% 7% 50%	5321
	11th to 20th	Night	5% 6% 2 4 3 3 3 3 5% 7% 59%	5296
	21st to end	Night	5% 4 2 5% 4 4 4 4 6% 8% 55%	5837
June	1st to 10th	Night	5% 5% 2 5% 4 3 4 4 5% 8% 56%	1754
	11th to 20th	Night	4 3 2 3 3 2 4 3 6% 6% 65%	1680
	21st to end	Night	3 3 1 4 3 3 3 3 5% 7% 66%	1814
July	1st to 10th	Night	2 2 1 4 3 4 4 3 5% 5% 66%	5340
	11th to 20th	Night	2 3 1 5% 4 5% 5% 5% 8% 10% 53%	5340
	21st to end	Night	2 2 1 4 3 3 5% 4 7% 8% 61%	5805
August	1st to 10th	Night	2 2 1 3 2 3 4 3 5% 8% 67%	4123
	11th to 20th	Night	2 2 1 4 3 5% 4 3 5% 6% 64%	4087
	21st to end	Night	3 3 2 5% 4 5% 5% 4 5% 6% 58%	4570
September	1st to 10th	Night	4 3 2 4 2 3 4 3 3 6% 66%	2127
	11th to 20th	Night	5% 3 1 5% 2 3 4 2 5% 7% 64%	2200
	21st to end	Night	5% 5% 1 3 3 2 2 2 4 5% 69%	2200
October	1st to 10th	Night	4 4 1 3 3 3 2 2 3 4 70%	3775
	11th to 20th	Night	7% 7% 2 4 3 3 4 3 5% 6% 57%	3898
	21st to end	Night	6% 8% 2 5% 3 4 4 4 6% 6% 52%	4252
November	1st to 10th	Night	6% 10% 3 6% 4 3 3 4 6% 7% 47%	2665
	11th to 20th	Night	8% 9% 3 7% 4 4 4 3 5% 7% 45%	2730
	21st to end	Night	6% 12% 4 7% 4 3 4 3 5% 6% 45%	2880
December	1st to 10th	Night	4 9% 3 7% 3 4 3 3 4 7% 54%	4710
	11th to 20th	Night	6% 13% 4 7% 4 4 5% 4 6% 6% 42%	5321
	21st to end	Night	6% 16% 5% 13% 6% 4 4 3 5% 6% 31%	6774

Transparency (when cloud cover <= 30%)
Color Meanings: Too cloudy to forecast Poor Below Average Average Above average Transparent
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	48% 12% 14% 15% 10% 1	5321
	11th to 20th	Day	40% 7% 10% 23% 13% 6%	5340
	21st to end	Day	35% 8% 16% 19% 20% 2	5844
February	1st to 10th	Day	52% 7% 13% 16% 10% 2	1890
	11th to 20th	Day	52% 9% 12% 16% 10% 1	1917
	21st to end	Day	51% 8% 12% 18% 10% 2	1730
March	1st to 10th	Day	42% 13% 10% 19% 11% 5%	4947
	11th to 20th	Day	31% 15% 15% 26% 12% 1	5110
	21st to end	Day	50% 12% 16% 15% 6% 1	5607
April	1st to 10th	Day	42% 8% 13% 19% 14% 4	2337
	11th to 20th	Day	42% 8% 12% 20% 16% 2	2650
	21st to end	Day	38% 8% 11% 24% 18% 1	2730
May	1st to 10th	Day	29% 10% 11% 22% 22% 6%	7626
	11th to 20th	Day	25% 9% 10% 22% 28% 5%	7599
	21st to end	Day	24% 8% 10% 24% 30% 4	8371
June	1st to 10th	Day	23% 7% 10% 21% 30% 8%	2856
	11th to 20th	Day	21% 4 8% 18% 27% 22%	2940
	21st to end	Day	15% 4 5% 13% 31% 32%	2795
July	1st to 10th	Day	11% 4 6% 7% 20% 52%	7586
	11th to 20th	Day	16% 7% 11% 12% 22% 31%	7581
	21st to end	Day	13% 6% 7% 14% 24% 37%	8120
August	1st to 10th	Day	18% 5% 7% 18% 24% 27%	4338
	11th to 20th	Day	15% 6% 8% 15% 32% 24%	4250
	21st to end	Day	14% 3 7% 16% 30% 29%	4614
September	1st to 10th	Day	17% 5% 7% 17% 29% 26%	2270
	11th to 20th	Day	22% 5% 8% 18% 28% 19%	2200
	21st to end	Day	21% 4 7% 20% 33% 15%	2200
October	1st to 10th	Day	22% 4 6% 14% 35% 20%	3417
	11th to 20th	Day	26% 4 8% 29% 26% 6%	3250
	21st to end	Day	29% 6% 11% 28% 22% 4	3533
November	1st to 10th	Day	35% 8% 13% 21% 17% 5%	1854
	11th to 20th	Day	39% 7% 12% 25% 15% 1	1890
	21st to end	Day	42% 6% 12% 24% 14% 3	1715
December	1st to 10th	Day	28% 8% 12% 38% 12% 3	2700
	11th to 20th	Day	43% 12% 15% 19% 11% 1	3104
	21st to end	Day	47% 11% 13% 15% 13% 1	4486
January	1st to 10th	Night	45% 11% 16% 16% 10% 2	7605
	11th to 20th	Night	37% 8% 9% 29% 14% 4	7650
	21st to end	Night	31% 9% 16% 18% 23% 3	8370
February	1st to 10th	Night	46% 8% 15% 19% 10% 2	2730
	11th to 20th	Night	45% 7% 12% 19% 15% 2	2595
	21st to end	Night	42% 8% 13% 21% 12% 3	2076
March	1st to 10th	Night	40% 12% 12% 18% 13% 5%	5165
	11th to 20th	Night	31% 13% 15% 25% 15% 1	5110
	21st to end	Night	39% 12% 16% 18% 13% 1	5610
April	1st to 10th	Night	37% 7% 14% 21% 17% 5%	2282
	11th to 20th	Night	32% 9% 13% 22% 20% 3	1917
	21st to end	Night	35% 9% 14% 23% 19% 1	1890
May	1st to 10th	Night	25% 9% 12% 21% 29% 4	5319
	11th to 20th	Night	19% 8% 10% 22% 32% 9%	5297
	21st to end	Night	21% 7% 11% 24% 35% 2	5838
June	1st to 10th	Night	24% 6% 10% 22% 31% 8%	1754
	11th to 20th	Night	17% 6% 8% 18% 29% 23%	1680
	21st to end	Night	16% 3 5% 11% 31% 33%	1814
July	1st to 10th	Night	16% 4 5% 8% 20% 48%	5295
	11th to 20th	Night	19% 6% 11% 11% 20% 33%	5286
	21st to end	Night	16% 6% 8% 13% 24% 33%	5677
August	1st to 10th	Night	18% 6% 8% 14% 27% 27%	3018
	11th to 20th	Night	22% 6% 8% 12% 27% 25%	2964
	21st to end	Night	14% 5% 8% 11% 31% 31%	3294
September	1st to 10th	Night	18% 5% 7% 17% 24% 29%	2127
	11th to 20th	Night	19% 5% 7% 19% 28% 21%	2200
	21st to end	Night	19% 3 7% 19% 34% 18%	2200
October	1st to 10th	Night	17% 4 7% 16% 35% 22%	3775
	11th to 20th	Night	25% 7% 7% 29% 25% 8%	3898
	21st to end	Night	26% 7% 10% 28% 26% 3	4252
November	1st to 10th	Night	31% 7% 12% 24% 21% 6%	2665
	11th to 20th	Night	33% 8% 13% 26% 17% 3	2730
	21st to end	Night	37% 5% 12% 26% 16% 4	2880
December	1st to 10th	Night	27% 8% 11% 34% 17% 2	4710
	11th to 20th	Night	35% 10% 20% 24% 11% 1	5322
	21st to end	Night	45% 11% 16% 16% 11% 2	6774

Seeing (when cloud cover <= 80%)
Color Meanings: Too cloudy to forecast Bad 1/5 Poor 2/5 Average 3/5 Good 4/5 Excellent 5/5
Month	Days in Month		Occurrence of each Forecast	Data Points
January	1st to 10th	Day	26% 17% 28% 18% 9% 1	330
	11th to 20th	Day	16% 15% 33% 23% 11% 2	330
	21st to end	Day	15% 16% 30% 30% 7% 1	363
February	1st to 10th	Day	28% 16% 31% 20% 6%	330
	11th to 20th	Day	20% 21% 33% 20% 5% 1	393
	21st to end	Day	18% 21% 36% 20% 4 1	446
March	1st to 10th	Day	20% 24% 31% 16% 8% 1	540
	11th to 20th	Day	16% 24% 34% 20% 7%	540
	21st to end	Day	22% 25% 32% 19% 2	594
April	1st to 10th	Day	21% 21% 29% 22% 6% 1	540
	11th to 20th	Day	23% 22% 32% 18% 4	532
	21st to end	Day	21% 23% 28% 21% 6% 1	540
May	1st to 10th	Day	15% 22% 37% 19% 6% 1	543
	11th to 20th	Day	16% 22% 31% 22% 8% 2	568
	21st to end	Day	13% 17% 31% 26% 11% 2	617
June	1st to 10th	Day	8% 17% 34% 29% 10% 2	696
	11th to 20th	Day	10% 16% 36% 26% 11% 1	780
	21st to end	Day	5% 18% 39% 30% 8% 1	635
July	1st to 10th	Day	3 13% 41% 33% 8% 2	566
	11th to 20th	Day	3 9% 41% 33% 11% 3	564
	21st to end	Day	4 7% 41% 34% 12% 2	619
August	1st to 10th	Day	5% 13% 38% 30% 12% 2	567
	11th to 20th	Day	4 10% 37% 35% 12% 3	534
	21st to end	Day	6% 12% 32% 36% 13% 3	583
September	1st to 10th	Day	4 11% 33% 33% 17% 3	530
	11th to 20th	Day	9% 18% 30% 31% 11% 1	530
	21st to end	Day	9% 13% 28% 33% 16% 1	530
October	1st to 10th	Day	13% 16% 28% 28% 14% 1	425
	11th to 20th	Day	14% 21% 22% 26% 16% 2	330
	21st to end	Day	14% 17% 31% 28% 9% 1	363
November	1st to 10th	Day	21% 19% 24% 27% 8% 2	330
	11th to 20th	Day	18% 13% 31% 26% 8% 4	330
	21st to end	Day	14% 15% 27% 28% 13% 2	330
December	1st to 10th	Day	17% 15% 26% 28% 10% 2	330
	11th to 20th	Day	19% 14% 32% 28% 7%	330
	21st to end	Day	28% 12% 30% 23% 6% 1	363
January	1st to 10th	Night	18% 9% 27% 28% 16% 3	840
	11th to 20th	Night	16% 7% 26% 34% 13% 3	840
	21st to end	Night	12% 10% 27% 33% 14% 3	924
February	1st to 10th	Night	18% 8% 28% 34% 11% 2	840
	11th to 20th	Night	15% 10% 29% 31% 13% 1	824
	21st to end	Night	13% 10% 34% 29% 12% 1	692
March	1st to 10th	Night	17% 11% 29% 30% 9% 3	840
	11th to 20th	Night	11% 11% 28% 34% 14% 2	840
	21st to end	Night	17% 12% 26% 33% 10% 2	924
April	1st to 10th	Night	17% 12% 25% 34% 11% 2	812
	11th to 20th	Night	14% 13% 27% 34% 10% 1	623
	21st to end	Night	14% 9% 25% 35% 16% 2	630
May	1st to 10th	Night	12% 8% 29% 35% 14% 1	630
	11th to 20th	Night	11% 7% 23% 37% 20% 3	621
	21st to end	Night	11% 7% 23% 35% 21% 4	683
June	1st to 10th	Night	9% 8% 19% 42% 21% 1	630
	11th to 20th	Night	6% 9% 23% 45% 16% 1	630
	21st to end	Night	5% 5% 22% 39% 27% 3	630
July	1st to 10th	Night	4 5% 20% 37% 32% 2	615
	11th to 20th	Night	6% 3 16% 45% 28% 2	612
	21st to end	Night	3 3 12% 43% 37% 1	690
August	1st to 10th	Night	4 3 18% 48% 25% 2	627
	11th to 20th	Night	3 2 20% 44% 29% 2	606
	21st to end	Night	5% 4 17% 47% 25% 2	660
September	1st to 10th	Night	5% 6% 15% 47% 24% 3	727
	11th to 20th	Night	7% 6% 21% 39% 23% 5%	800
	21st to end	Night	7% 5% 20% 33% 27% 7%	800
October	1st to 10th	Night	10% 6% 25% 38% 17% 4	800
	11th to 20th	Night	13% 5% 22% 35% 21% 4	800
	21st to end	Night	12% 8% 22% 37% 19% 3	880
November	1st to 10th	Night	14% 10% 21% 34% 18% 3	820
	11th to 20th	Night	15% 7% 26% 34% 14% 4	840
	21st to end	Night	14% 10% 25% 33% 14% 4	990
December	1st to 10th	Night	15% 9% 28% 33% 15% 1	1050
	11th to 20th	Night	19% 9% 27% 33% 10% 2	1050
	21st to end	Night	23% 12% 24% 31% 8% 1	996

Page generated at 2026-08-12 01:37:16. Version ac07

Copyright © 2026 Attilla Danko.