Freeman Reservoir Campground
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Freeman Reservoir Campground clear sky chart from 2005-11-06 to 2026-03-18.

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	5% 10% 3 7% 4 4 4 3 5% 6% 47%	140358
	Night	6% 11% 4 7% 4 4 4 3 5% 6% 45%	138695
Transparency	Day	36% 6% 9% 22% 19% 8%	135227
	Night	38% 6% 10% 22% 18% 7%	134833
Seeing	Day	15% 17% 31% 24% 11% 2	17369
	Night	15% 9% 25% 33% 16% 2	27604

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	5% 18% 7% 16% 5% 4 3 3 4 6% 27%	4720
	11th to 20th	Day	3 13% 5% 11% 8% 4 4 3 5% 5% 39%	5254
	21st to end	Day	2 16% 8% 10% 5% 4 4 3 4 5% 39%	5844
February	1st to 10th	Day	9% 20% 6% 10% 6% 3 3 2 5% 6% 29%	1890
	11th to 20th	Day	7% 23% 8% 11% 4 4 3 2 4 4 29%	1855
	21st to end	Day	4 17% 7% 14% 6% 4 4 3 4 5% 32%	1730
March	1st to 10th	Day	4 15% 7% 10% 4 5% 4 3 5% 5% 38%	4920
	11th to 20th	Day	2 15% 6% 11% 5% 4 4 3 5% 5% 40%	5078
	21st to end	Day	7% 23% 6% 11% 5% 4 4 3 5% 5% 27%	5571
April	1st to 10th	Day	8% 16% 4 8% 4 4 4 4 5% 6% 38%	2400
	11th to 20th	Day	9% 15% 3 9% 6% 5% 5% 4 4 5% 35%	2371
	21st to end	Day	7% 14% 3 7% 6% 5% 5% 4 5% 6% 37%	2421
May	1st to 10th	Day	8% 15% 4 8% 5% 5% 5% 4 5% 6% 35%	5880
	11th to 20th	Day	5% 8% 2 7% 5% 5% 6% 5% 7% 8% 43%	6293
	21st to end	Day	6% 7% 2 6% 4 4 5% 4 6% 7% 49%	6925
June	1st to 10th	Day	6% 4 2 5% 4 5% 4 4 6% 8% 52%	2800
	11th to 20th	Day	6% 3 1 4 4 3 4 3 5% 7% 58%	2800
	21st to end	Day	3 3 1 4 3 4 4 3 5% 6% 63%	2800
July	1st to 10th	Day	3 2 1 3 3 3 4 3 5% 7% 65%	6339
	11th to 20th	Day	2 2 1 4 5% 4 5% 4 7% 9% 56%	6340
	21st to end	Day	3 3 2 4 4 3 5% 5% 7% 8% 57%	6415
August	1st to 10th	Day	3 3 2 5% 4 5% 6% 4 7% 8% 53%	5779
	11th to 20th	Day	4 3 1 4 3 4 5% 4 6% 8% 57%	5720
	21st to end	Day	9% 5% 2 5% 5% 4 4 3 5% 6% 50%	5984
September	1st to 10th	Day	5% 4 1 3 3 3 3 3 5% 5% 64%	2400
	11th to 20th	Day	8% 4 2 4 4 4 4 3 5% 6% 56%	2400
	21st to end	Day	8% 4 2 4 3 3 3 3 4 6% 61%	2111
October	1st to 10th	Day	6% 5% 1 3 3 2 3 2 3 4 69%	3270
	11th to 20th	Day	8% 7% 2 5% 3 3 4 3 5% 7% 53%	3250
	21st to end	Day	8% 12% 4 5% 3 2 3 2 4 6% 51%	3548
November	1st to 10th	Day	9% 11% 4 6% 3 3 3 2 5% 6% 48%	1903
	11th to 20th	Day	9% 14% 3 6% 4 3 4 3 4 6% 44%	1769
	21st to end	Day	6% 14% 5% 8% 4 3 3 2 5% 6% 44%	1680
December	1st to 10th	Day	5% 13% 3 11% 4 2 3 2 3 5% 50%	2700
	11th to 20th	Day	6% 15% 6% 8% 3 3 3 3 5% 6% 42%	3106
	21st to end	Day	7% 21% 5% 12% 4 3 3 3 5% 7% 31%	4092
January	1st to 10th	Night	6% 17% 6% 15% 6% 5% 5% 3 5% 4 28%	8201
	11th to 20th	Night	3 14% 5% 9% 6% 3 3 3 4 5% 45%	7793
	21st to end	Night	3 15% 6% 9% 4 4 3 3 4 5% 44%	8370
February	1st to 10th	Night	10% 18% 6% 11% 6% 4 4 3 4 4 30%	2730
	11th to 20th	Night	7% 21% 7% 9% 5% 4 3 3 4 4 31%	2651
	21st to end	Night	6% 18% 5% 10% 5% 4 3 3 5% 6% 35%	2076
March	1st to 10th	Night	4 16% 6% 8% 3 4 3 3 5% 6% 42%	5185
	11th to 20th	Night	3 12% 4 7% 4 4 5% 4 6% 7% 44%	5077
	21st to end	Night	7% 23% 5% 9% 4 5% 4 3 5% 5% 29%	5398
April	1st to 10th	Night	9% 15% 3 6% 5% 3 5% 3 5% 5% 41%	2000
	11th to 20th	Night	12% 12% 3 8% 5% 4 5% 3 5% 7% 37%	1977
	21st to end	Night	9% 12% 3 6% 5% 5% 4 3 6% 6% 40%	1975
May	1st to 10th	Night	8% 11% 3 6% 4 4 4 4 6% 8% 42%	4100
	11th to 20th	Night	9% 11% 3 8% 5% 5% 5% 3 6% 7% 38%	3620
	21st to end	Night	9% 8% 2 6% 4 4 5% 3 4 6% 49%	3972
June	1st to 10th	Night	6% 5% 2 4 4 3 4 4 7% 8% 53%	1600
	11th to 20th	Night	8% 5% 1 5% 4 4 4 3 6% 6% 55%	1600
	21st to end	Night	4 3 1 4 3 3 3 3 5% 6% 65%	1600
July	1st to 10th	Night	5% 3 2 5% 4 4 5% 4 6% 7% 57%	3640
	11th to 20th	Night	3 4 2 6% 5% 4 5% 5% 7% 9% 49%	3640
	21st to end	Night	2 3 2 6% 3 4 5% 4 6% 9% 55%	4440
August	1st to 10th	Night	4 4 2 5% 4 5% 5% 4 6% 8% 52%	4033
	11th to 20th	Night	4 3 2 5% 4 5% 6% 5% 6% 7% 54%	4129
	21st to end	Night	5% 5% 1 6% 5% 5% 6% 4 6% 7% 51%	4993
September	1st to 10th	Night	6% 4 1 4 3 3 3 3 5% 5% 62%	2000
	11th to 20th	Night	7% 5% 2 4 4 3 4 3 5% 6% 57%	2000
	21st to end	Night	7% 4 1 3 3 2 3 3 3 5% 66%	2285
October	1st to 10th	Night	7% 5% 1 3 2 2 3 2 3 4 69%	3920
	11th to 20th	Night	9% 7% 1 5% 3 3 3 3 5% 6% 55%	3898
	21st to end	Night	7% 11% 3 5% 3 3 3 2 4 6% 52%	4252
November	1st to 10th	Night	9% 12% 3 5% 3 3 3 3 5% 5% 49%	2595
	11th to 20th	Night	9% 11% 3 7% 4 4 4 3 4 5% 44%	2846
	21st to end	Night	6% 13% 4 8% 4 3 3 3 4 6% 46%	2940
December	1st to 10th	Night	5% 11% 4 8% 3 2 2 2 3 5% 53%	4710
	11th to 20th	Night	6% 13% 5% 8% 4 4 5% 3 5% 7% 40%	5321
	21st to end	Night	7% 18% 6% 10% 5% 4 4 3 5% 6% 33%	7128

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	56% 7% 13% 14% 10% 1	4723
	11th to 20th	Day	43% 7% 17% 20% 9% 4	5254
	21st to end	Day	44% 8% 10% 18% 16% 4	5844
February	1st to 10th	Day	56% 6% 11% 17% 9% 1	1890
	11th to 20th	Day	59% 6% 9% 17% 8% 2	1864
	21st to end	Day	53% 5% 10% 18% 13% 1	1730
March	1st to 10th	Day	43% 8% 8% 22% 12% 6%	4920
	11th to 20th	Day	45% 5% 11% 28% 10% 1	5078
	21st to end	Day	53% 10% 10% 19% 7% 1	5571
April	1st to 10th	Day	46% 7% 11% 18% 15% 4	2400
	11th to 20th	Day	50% 6% 7% 20% 14% 3	2374
	21st to end	Day	44% 7% 8% 26% 14% 1	2421
May	1st to 10th	Day	45% 9% 9% 17% 19% 2	5880
	11th to 20th	Day	32% 9% 9% 30% 19% 1	6297
	21st to end	Day	28% 8% 6% 29% 26% 2	6926
June	1st to 10th	Day	28% 7% 9% 23% 24% 8%	2800
	11th to 20th	Day	24% 6% 6% 16% 30% 18%	2800
	21st to end	Day	20% 5% 4 17% 32% 21%	2800
July	1st to 10th	Day	16% 5% 5% 13% 25% 36%	6271
	11th to 20th	Day	21% 5% 6% 20% 30% 18%	6265
	21st to end	Day	21% 6% 9% 16% 28% 21%	6230
August	1st to 10th	Day	27% 7% 9% 22% 17% 16%	4208
	11th to 20th	Day	27% 7% 8% 19% 25% 13%	4143
	21st to end	Day	26% 6% 7% 19% 25% 18%	4311
September	1st to 10th	Day	21% 5% 6% 18% 29% 21%	2400
	11th to 20th	Day	27% 6% 7% 20% 28% 12%	2400
	21st to end	Day	25% 4 5% 27% 32% 7%	2111
October	1st to 10th	Day	21% 4 5% 24% 36% 11%	3270
	11th to 20th	Day	30% 5% 6% 34% 22% 3	3250
	21st to end	Day	35% 4 9% 35% 15% 2	3548
November	1st to 10th	Day	37% 5% 9% 28% 19% 2	1903
	11th to 20th	Day	42% 6% 13% 23% 14% 1	1769
	21st to end	Day	41% 4 12% 28% 14% 1	1680
December	1st to 10th	Day	39% 4 12% 34% 10% 1	2700
	11th to 20th	Day	42% 5% 17% 27% 9%	3104
	21st to end	Day	53% 6% 9% 19% 11% 2	4092
January	1st to 10th	Night	56% 6% 10% 16% 8% 3	8202
	11th to 20th	Night	41% 5% 16% 23% 14% 2	7793
	21st to end	Night	42% 6% 10% 17% 20% 4	8370
February	1st to 10th	Night	57% 6% 8% 18% 9% 1	2730
	11th to 20th	Night	55% 6% 9% 19% 11% 2	2652
	21st to end	Night	49% 6% 9% 18% 14% 3	2076
March	1st to 10th	Night	41% 6% 8% 24% 14% 7%	5185
	11th to 20th	Night	34% 6% 10% 32% 16% 2	5077
	21st to end	Night	53% 8% 11% 21% 6% 1	5398
April	1st to 10th	Night	43% 7% 11% 20% 15% 5%	2000
	11th to 20th	Night	46% 5% 9% 21% 16% 2	1977
	21st to end	Night	42% 6% 9% 23% 18% 1	1975
May	1st to 10th	Night	37% 8% 11% 23% 19% 3	4097
	11th to 20th	Night	40% 8% 9% 27% 12% 3	3621
	21st to end	Night	32% 8% 8% 29% 22% 1	3972
June	1st to 10th	Night	26% 6% 10% 26% 23% 9%	1600
	11th to 20th	Night	29% 5% 7% 14% 25% 20%	1600
	21st to end	Night	18% 5% 4 17% 31% 25%	1600
July	1st to 10th	Night	24% 5% 6% 11% 21% 33%	3600
	11th to 20th	Night	25% 6% 7% 22% 24% 15%	3592
	21st to end	Night	23% 6% 8% 19% 26% 18%	4313
August	1st to 10th	Night	25% 7% 11% 22% 16% 19%	2928
	11th to 20th	Night	31% 8% 10% 14% 23% 14%	2982
	21st to end	Night	28% 5% 8% 16% 26% 18%	3597
September	1st to 10th	Night	22% 5% 6% 18% 26% 23%	2000
	11th to 20th	Night	26% 6% 7% 22% 25% 14%	2000
	21st to end	Night	22% 4 5% 24% 36% 10%	2285
October	1st to 10th	Night	20% 3 5% 19% 39% 14%	3920
	11th to 20th	Night	30% 4 6% 33% 24% 4	3898
	21st to end	Night	33% 4 10% 32% 17% 3	4252
November	1st to 10th	Night	36% 5% 9% 26% 21% 3	2595
	11th to 20th	Night	41% 5% 11% 27% 14% 2	2846
	21st to end	Night	41% 4 9% 29% 16% 2	2940
December	1st to 10th	Night	36% 4 11% 33% 15% 1	4710
	11th to 20th	Night	43% 6% 17% 24% 9%	5322
	21st to end	Night	52% 6% 10% 19% 12% 2	7128

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	25% 22% 26% 19% 6% 2	330
	11th to 20th	Day	17% 23% 32% 22% 5% 1	330
	21st to end	Day	12% 26% 37% 21% 3 1	363
February	1st to 10th	Day	29% 28% 27% 13% 3	330
	11th to 20th	Day	30% 26% 26% 15% 2	330
	21st to end	Day	24% 27% 31% 15% 3	273
March	1st to 10th	Day	22% 27% 29% 16% 5%	469
	11th to 20th	Day	22% 26% 30% 17% 5% 1	529
	21st to end	Day	25% 22% 36% 13% 3 1	550
April	1st to 10th	Day	22% 26% 31% 15% 5% 1	500
	11th to 20th	Day	23% 29% 30% 15% 3	492
	21st to end	Day	22% 21% 30% 20% 7% 1	500
May	1st to 10th	Day	21% 21% 29% 20% 7% 1	503
	11th to 20th	Day	17% 12% 30% 24% 15% 3	720
	21st to end	Day	14% 16% 29% 24% 15% 2	789
June	1st to 10th	Day	7% 13% 28% 31% 16% 4	730
	11th to 20th	Day	10% 16% 35% 25% 13% 1	730
	21st to end	Day	8% 13% 33% 28% 16% 3	730
July	1st to 10th	Day	6% 7% 28% 34% 22% 3	721
	11th to 20th	Day	5% 6% 28% 36% 20% 5%	718
	21st to end	Day	7% 7% 30% 36% 19% 2	589
August	1st to 10th	Day	7% 11% 35% 34% 11% 2	527
	11th to 20th	Day	6% 9% 33% 33% 15% 4	517
	21st to end	Day	8% 11% 33% 29% 16% 3	583
September	1st to 10th	Day	7% 10% 32% 34% 13% 4	530
	11th to 20th	Day	10% 14% 38% 23% 12% 3	530
	21st to end	Day	11% 18% 27% 26% 14% 5%	420
October	1st to 10th	Day	16% 12% 28% 24% 17% 4	330
	11th to 20th	Day	18% 19% 28% 23% 8% 4	330
	21st to end	Day	21% 18% 34% 18% 8% 1	363
November	1st to 10th	Day	22% 25% 28% 17% 8% 1	330
	11th to 20th	Day	18% 23% 33% 21% 4 1	330
	21st to end	Day	16% 22% 34% 22% 5% 1	330
December	1st to 10th	Day	26% 21% 25% 20% 6% 1	330
	11th to 20th	Day	18% 24% 38% 16% 5%	330
	21st to end	Day	28% 20% 34% 14% 3 1	363
January	1st to 10th	Night	17% 13% 27% 31% 10% 1	1050
	11th to 20th	Night	18% 12% 30% 29% 9% 1	892
	21st to end	Night	15% 12% 31% 31% 10% 2	924
February	1st to 10th	Night	21% 12% 35% 24% 8% 1	840
	11th to 20th	Night	18% 15% 30% 29% 7%	824
	21st to end	Night	17% 14% 33% 32% 4	692
March	1st to 10th	Night	16% 13% 28% 31% 10% 1	840
	11th to 20th	Night	13% 11% 27% 36% 11% 1	828
	21st to end	Night	18% 12% 27% 30% 12% 1	840
April	1st to 10th	Night	20% 12% 27% 33% 8%	600
	11th to 20th	Night	19% 11% 28% 30% 10% 2	593
	21st to end	Night	19% 11% 22% 32% 15% 2	600
May	1st to 10th	Night	18% 10% 26% 30% 14% 2	600
	11th to 20th	Night	15% 7% 20% 34% 22% 3	591
	21st to end	Night	14% 8% 20% 33% 21% 3	650
June	1st to 10th	Night	9% 7% 21% 35% 25% 3	600
	11th to 20th	Night	11% 9% 25% 37% 17% 1	600
	21st to end	Night	6% 5% 20% 43% 25% 2	600
July	1st to 10th	Night	7% 2 18% 35% 35% 2	585
	11th to 20th	Night	4 2 13% 45% 31% 4	582
	21st to end	Night	5% 1 12% 41% 38% 4	657
August	1st to 10th	Night	6% 2 14% 38% 37% 3	597
	11th to 20th	Night	7% 2 12% 44% 31% 4	594
	21st to end	Night	7% 2 13% 39% 33% 7%	660
September	1st to 10th	Night	8% 2 16% 39% 30% 5%	600
	11th to 20th	Night	10% 3 17% 38% 28% 3	600
	21st to end	Night	9% 6% 18% 30% 28% 8%	775
October	1st to 10th	Night	15% 5% 24% 31% 23% 3	800
	11th to 20th	Night	14% 10% 22% 36% 16% 3	800
	21st to end	Night	16% 10% 23% 32% 16% 3	880
November	1st to 10th	Night	17% 13% 25% 30% 14% 2	955
	11th to 20th	Night	18% 13% 29% 30% 9% 1	1050
	21st to end	Night	14% 13% 27% 36% 10% 1	1050
December	1st to 10th	Night	20% 11% 29% 30% 10% 1	1050
	11th to 20th	Night	19% 12% 32% 29% 7% 1	1050
	21st to end	Night	22% 14% 33% 23% 7% 1	1155

Page generated at 2026-03-15 00:23:53. Version ac07

Copyright © 2026 Attilla Danko.