Moose Springs
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Moose Springs clear sky chart from 2005-11-06 to 2025-03-27.

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 10% 4 8% 5% 4 4 3 5% 6% 47%	113066
	Night	3 9% 4 9% 5% 4 4 3 5% 6% 49%	115136
Transparency	Day	35% 6% 10% 19% 20% 11%	112831
	Night	33% 5% 11% 21% 20% 9%	114960
Seeing	Day	12% 19% 33% 23% 10% 2	15612
	Night	8% 11% 28% 34% 17% 2	26051

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	1 10% 8% 19% 8% 4 4 3 5% 5% 31%	4098
	11th to 20th	Day	2 11% 6% 16% 12% 5% 2 2 3 3 37%	4100
	21st to end	Day	2 12% 7% 13% 4 3 2 2 3 5% 48%	4510
February	1st to 10th	Day	3 16% 7% 12% 8% 5% 4 4 4 4 33%	1800
	11th to 20th	Day	3 20% 8% 11% 6% 4 4 3 5% 5% 31%	1790
	21st to end	Day	3 15% 7% 17% 6% 4 3 3 5% 5% 32%	1650
March	1st to 10th	Day	2 16% 7% 16% 6% 4 4 3 5% 6% 32%	3516
	11th to 20th	Day	2 12% 4 9% 5% 5% 6% 4 6% 7% 41%	3600
	21st to end	Day	3 26% 11% 11% 5% 4 4 4 5% 5% 21%	3892
April	1st to 10th	Day	4 16% 5% 9% 5% 5% 4 4 5% 6% 38%	2135
	11th to 20th	Day	4 17% 6% 10% 4 4 5% 4 5% 6% 35%	2348
	21st to end	Day	6% 15% 4 6% 4 4 4 3 5% 6% 42%	2470
May	1st to 10th	Day	6% 17% 7% 8% 5% 5% 5% 3 6% 6% 33%	4110
	11th to 20th	Day	5% 8% 2 5% 4 4 4 4 7% 8% 48%	4071
	21st to end	Day	6% 10% 3 7% 4 4 5% 4 6% 7% 43%	4477
June	1st to 10th	Day	4 5% 2 4 5% 5% 5% 4 6% 8% 53%	2641
	11th to 20th	Day	5% 5% 1 5% 3 4 3 2 5% 6% 59%	2660
	21st to end	Day	2 3 1 5% 3 3 3 3 6% 5% 65%	2584
July	1st to 10th	Day	2 2 1 3 2 3 2 3 4 5% 72%	4110
	11th to 20th	Day	4 5% 2 5% 5% 5% 6% 5% 7% 9% 48%	4110
	21st to end	Day	4 3 2 5% 4 4 4 4 5% 7% 58%	4454
August	1st to 10th	Day	4 4 1 6% 5% 4 5% 4 6% 6% 56%	4092
	11th to 20th	Day	3 3 2 5% 4 4 5% 3 5% 6% 60%	4028
	21st to end	Day	4 4 1 4 4 4 4 4 5% 5% 63%	4433
September	1st to 10th	Day	5% 4 2 4 4 3 4 3 5% 6% 61%	2190
	11th to 20th	Day	6% 5% 1 4 3 3 4 3 5% 5% 59%	2090
	21st to end	Day	5% 7% 1 3 2 2 3 3 4 4 65%	2090
October	1st to 10th	Day	5% 7% 1 4 3 2 3 2 5% 3 64%	3280
	11th to 20th	Day	8% 10% 3 5% 3 3 3 3 4 5% 52%	3150
	21st to end	Day	3 10% 3 7% 3 3 3 3 4 5% 57%	3438
November	1st to 10th	Day	6% 10% 4 7% 4 3 4 3 4 7% 48%	1802
	11th to 20th	Day	3 14% 4 6% 4 4 4 3 5% 7% 47%	1795
	21st to end	Day	2 11% 5% 11% 4 5% 4 3 6% 6% 44%	1600
December	1st to 10th	Day	2 8% 3 7% 5% 3 3 3 4 7% 55%	2620
	11th to 20th	Day	3 10% 7% 13% 6% 5% 5% 4 6% 6% 35%	3026
	21st to end	Day	3 17% 7% 13% 5% 5% 4 3 4 6% 34%	4306
January	1st to 10th	Night	1 9% 6% 22% 6% 4 4 3 5% 5% 34%	5867
	11th to 20th	Night	2 13% 6% 13% 11% 5% 4 3 4 4 35%	5880
	21st to end	Night	1 11% 7% 11% 4 3 3 2 4 5% 49%	6468
February	1st to 10th	Night	2 13% 5% 12% 7% 5% 4 4 6% 5% 37%	2600
	11th to 20th	Night	2 13% 5% 10% 6% 5% 5% 3 5% 5% 40%	2493
	21st to end	Night	2 12% 5% 13% 7% 5% 4 4 5% 6% 38%	1980
March	1st to 10th	Night	1 12% 6% 15% 7% 5% 5% 3 5% 6% 35%	3577
	11th to 20th	Night	1 8% 4 8% 5% 4 4 5% 7% 7% 46%	3600
	21st to end	Night	2 17% 7% 13% 5% 4 4 4 5% 5% 34%	3899
April	1st to 10th	Night	5% 14% 4 7% 4 4 4 2 5% 6% 46%	2043
	11th to 20th	Night	4 10% 4 6% 5% 5% 5% 4 6% 7% 45%	1776
	21st to end	Night	6% 12% 3 6% 4 3 4 4 6% 7% 45%	1710
May	1st to 10th	Night	4 12% 5% 7% 6% 5% 5% 4 6% 7% 39%	2860
	11th to 20th	Night	3 5% 1 4 3 3 4 4 5% 7% 60%	2834
	21st to end	Night	4 7% 2 5% 4 4 5% 3 6% 8% 52%	3110
June	1st to 10th	Night	4 5% 2 5% 4 4 5% 4 6% 7% 55%	1534
	11th to 20th	Night	4 4 1 4 4 3 3 3 5% 6% 64%	1520
	21st to end	Night	2 2 2 3 2 3 4 3 5% 7% 66%	1587
July	1st to 10th	Night	4 3 1 3 3 2 3 3 4 4 70%	2860
	11th to 20th	Night	3 4 2 6% 5% 6% 6% 6% 7% 8% 49%	2860
	21st to end	Night	3 4 2 6% 5% 5% 5% 4 6% 5% 56%	3109
August	1st to 10th	Night	4 4 2 5% 4 4 4 3 5% 8% 57%	2847
	11th to 20th	Night	4 4 2 5% 4 4 4 4 5% 6% 57%	2811
	21st to end	Night	2 3 1 3 2 3 4 3 5% 6% 68%	3233
September	1st to 10th	Night	3 3 1 3 3 3 4 3 5% 6% 66%	1985
	11th to 20th	Night	4 3 1 3 3 3 3 3 6% 6% 63%	2090
	21st to end	Night	5% 5% 1 3 2 2 2 2 4 5% 68%	2090
October	1st to 10th	Night	4 4 2 3 2 2 2 2 4 4 71%	3693
	11th to 20th	Night	7% 7% 2 6% 3 3 3 3 4 6% 57%	3778
	21st to end	Night	4 9% 3 7% 3 3 3 3 5% 6% 55%	4120
November	1st to 10th	Night	3 10% 3 6% 4 3 3 4 6% 7% 49%	2492
	11th to 20th	Night	3 11% 3 7% 3 3 4 3 6% 8% 49%	2600
	21st to end	Night	2 10% 4 10% 5% 4 4 3 5% 7% 46%	2781
December	1st to 10th	Night	2 7% 3 7% 6% 5% 3 3 4 6% 56%	4570
	11th to 20th	Night	2 11% 5% 10% 5% 4 4 4 6% 7% 42%	5181
	21st to end	Night	2 14% 6% 14% 6% 5% 4 4 5% 7% 33%	6698

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% 7% 13% 16% 13% 3	4099
	11th to 20th	Day	51% 5% 8% 15% 15% 5%	4100
	21st to end	Day	38% 5% 14% 14% 20% 10%	4510
February	1st to 10th	Day	53% 6% 11% 15% 10% 4	1800
	11th to 20th	Day	53% 5% 11% 18% 11% 2	1799
	21st to end	Day	51% 6% 11% 17% 12% 3	1650
March	1st to 10th	Day	48% 8% 10% 21% 10% 5%	3516
	11th to 20th	Day	36% 9% 19% 26% 8% 2	3600
	21st to end	Day	60% 7% 13% 14% 4 1	3892
April	1st to 10th	Day	43% 7% 14% 18% 14% 4	2135
	11th to 20th	Day	47% 7% 12% 21% 14% 1	2351
	21st to end	Day	41% 7% 11% 27% 14% 1	2470
May	1st to 10th	Day	42% 9% 12% 19% 14% 3	4110
	11th to 20th	Day	27% 7% 11% 34% 20% 2	4074
	21st to end	Day	33% 7% 11% 25% 21% 2	4477
June	1st to 10th	Day	25% 7% 11% 24% 26% 7%	2641
	11th to 20th	Day	24% 4 8% 19% 28% 17%	2660
	21st to end	Day	20% 3 7% 13% 29% 29%	2584
July	1st to 10th	Day	14% 3 6% 8% 16% 53%	4046
	11th to 20th	Day	29% 5% 5% 15% 25% 21%	4041
	21st to end	Day	23% 5% 7% 11% 25% 28%	4314
August	1st to 10th	Day	26% 5% 9% 23% 19% 17%	4078
	11th to 20th	Day	24% 4 7% 18% 27% 19%	4067
	21st to end	Day	22% 3 7% 15% 31% 21%	4432
September	1st to 10th	Day	23% 5% 8% 15% 26% 23%	2190
	11th to 20th	Day	25% 6% 7% 18% 25% 19%	2090
	21st to end	Day	23% 4 7% 20% 35% 12%	2090
October	1st to 10th	Day	24% 4 5% 20% 36% 11%	3280
	11th to 20th	Day	35% 3 5% 30% 23% 4	3150
	21st to end	Day	31% 3 10% 27% 26% 3	3438
November	1st to 10th	Day	35% 7% 11% 23% 20% 4	1802
	11th to 20th	Day	34% 5% 14% 25% 20% 2	1795
	21st to end	Day	39% 6% 12% 23% 15% 6%	1600
December	1st to 10th	Day	29% 5% 10% 33% 19% 4	2620
	11th to 20th	Day	47% 5% 13% 19% 15% 1	3024
	21st to end	Day	50% 4 9% 13% 16% 6%	4306
January	1st to 10th	Night	48% 7% 10% 14% 16% 5%	5867
	11th to 20th	Night	51% 5% 8% 15% 17% 4	5880
	21st to end	Night	36% 5% 13% 18% 19% 9%	6468
February	1st to 10th	Night	45% 8% 13% 19% 11% 3	2600
	11th to 20th	Night	43% 5% 12% 20% 17% 2	2494
	21st to end	Night	44% 6% 13% 20% 11% 6%	1980
March	1st to 10th	Night	40% 8% 14% 21% 13% 3	3577
	11th to 20th	Night	28% 10% 20% 29% 11% 2	3600
	21st to end	Night	45% 9% 14% 20% 11% 2	3899
April	1st to 10th	Night	37% 6% 15% 20% 17% 5%	2043
	11th to 20th	Night	34% 6% 16% 26% 17% 2	1776
	21st to end	Night	35% 6% 15% 26% 18% 1	1710
May	1st to 10th	Night	38% 7% 13% 20% 19% 2	2860
	11th to 20th	Night	20% 7% 11% 33% 24% 5%	2835
	21st to end	Night	25% 7% 13% 30% 23% 2	3110
June	1st to 10th	Night	24% 6% 11% 24% 27% 7%	1534
	11th to 20th	Night	21% 5% 8% 18% 31% 18%	1520
	21st to end	Night	16% 3 6% 15% 27% 33%	1587
July	1st to 10th	Night	17% 3 6% 9% 12% 53%	2815
	11th to 20th	Night	29% 5% 6% 13% 24% 23%	2806
	21st to end	Night	27% 5% 8% 15% 22% 23%	3011
August	1st to 10th	Night	25% 4 9% 22% 21% 19%	2838
	11th to 20th	Night	28% 4 7% 16% 25% 20%	2838
	21st to end	Night	17% 4 9% 15% 30% 25%	3233
September	1st to 10th	Night	18% 4 7% 18% 27% 25%	1985
	11th to 20th	Night	19% 5% 10% 20% 27% 18%	2090
	21st to end	Night	20% 4 5% 19% 37% 15%	2090
October	1st to 10th	Night	18% 3 6% 24% 36% 13%	3693
	11th to 20th	Night	29% 4 5% 30% 26% 6%	3778
	21st to end	Night	29% 4 8% 30% 25% 4	4120
November	1st to 10th	Night	31% 5% 13% 23% 21% 5%	2492
	11th to 20th	Night	31% 5% 14% 29% 19% 3	2600
	21st to end	Night	36% 5% 11% 22% 19% 7%	2781
December	1st to 10th	Night	29% 4 10% 31% 19% 7%	4570
	11th to 20th	Night	40% 5% 16% 25% 13% 1	5182
	21st to end	Night	47% 5% 13% 17% 12% 5%	6698

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	17% 23% 27% 20% 11% 1	300
	11th to 20th	Day	15% 21% 33% 21% 8% 1	300
	21st to end	Day	9% 25% 37% 22% 6% 1	330
February	1st to 10th	Day	24% 26% 35% 11% 3	300
	11th to 20th	Day	17% 30% 33% 15% 4 1	335
	21st to end	Day	16% 30% 36% 14% 3	414
March	1st to 10th	Day	17% 28% 33% 16% 6%	500
	11th to 20th	Day	15% 29% 32% 20% 4	500
	21st to end	Day	21% 30% 34% 13% 2	531
April	1st to 10th	Day	20% 26% 29% 18% 5% 2	460
	11th to 20th	Day	22% 28% 32% 13% 4 1	452
	21st to end	Day	22% 25% 27% 21% 5% 1	460
May	1st to 10th	Day	18% 25% 35% 14% 6% 1	463
	11th to 20th	Day	16% 21% 31% 21% 9% 2	488
	21st to end	Day	16% 21% 29% 22% 10% 2	529
June	1st to 10th	Day	6% 15% 35% 26% 16% 2	661
	11th to 20th	Day	9% 19% 34% 24% 12% 1	680
	21st to end	Day	6% 13% 41% 27% 12% 1	604
July	1st to 10th	Day	4 11% 37% 35% 11% 1	486
	11th to 20th	Day	6% 7% 44% 29% 11% 2	484
	21st to end	Day	4 4 38% 36% 14% 4	531
August	1st to 10th	Day	7% 9% 40% 30% 11% 3	487
	11th to 20th	Day	4 12% 34% 34% 12% 4	477
	21st to end	Day	5% 12% 34% 32% 12% 4	539
September	1st to 10th	Day	6% 13% 29% 30% 16% 6%	490
	11th to 20th	Day	10% 19% 32% 24% 12% 3	490
	21st to end	Day	11% 16% 25% 30% 15% 3	490
October	1st to 10th	Day	12% 16% 27% 23% 15% 5%	371
	11th to 20th	Day	13% 18% 26% 25% 16% 3	300
	21st to end	Day	15% 20% 34% 22% 8%	330
November	1st to 10th	Day	20% 20% 27% 20% 12% 1	300
	11th to 20th	Day	12% 21% 36% 20% 9% 3	300
	21st to end	Day	13% 16% 32% 26% 11% 3	300
December	1st to 10th	Day	9% 18% 36% 24% 10% 3	300
	11th to 20th	Day	8% 24% 35% 26% 6% 1	300
	21st to end	Day	20% 24% 28% 21% 5% 1	330
January	1st to 10th	Night	9% 15% 32% 28% 13% 2	800
	11th to 20th	Night	9% 14% 33% 30% 11% 2	800
	21st to end	Night	7% 12% 37% 31% 11% 2	880
February	1st to 10th	Night	12% 15% 39% 24% 9% 1	800
	11th to 20th	Night	7% 16% 37% 29% 10% 1	784
	21st to end	Night	10% 14% 41% 27% 8% 1	660
March	1st to 10th	Night	9% 17% 32% 32% 8% 2	800
	11th to 20th	Night	8% 13% 31% 34% 14% 2	800
	21st to end	Night	10% 16% 35% 29% 8% 1	862
April	1st to 10th	Night	13% 16% 29% 30% 11% 1	713
	11th to 20th	Night	10% 16% 34% 32% 9%	563
	21st to end	Night	12% 13% 29% 29% 15% 1	570
May	1st to 10th	Night	10% 12% 34% 30% 13% 1	570
	11th to 20th	Night	8% 5% 28% 37% 21% 2	561
	21st to end	Night	9% 9% 27% 34% 18% 2	617
June	1st to 10th	Night	6% 8% 25% 38% 20% 2	570
	11th to 20th	Night	6% 10% 29% 38% 16% 1	570
	21st to end	Night	3 4 25% 41% 26% 2	570
July	1st to 10th	Night	4 3 18% 40% 33% 3	555
	11th to 20th	Night	5% 2 17% 42% 31% 3	552
	21st to end	Night	3 2 10% 41% 42% 2	624
August	1st to 10th	Night	5% 2 17% 45% 30% 2	567
	11th to 20th	Night	6% 3 13% 42% 33% 3	564
	21st to end	Night	5% 3 15% 43% 32% 2	627
September	1st to 10th	Night	4 4 20% 37% 31% 4	655
	11th to 20th	Night	6% 6% 17% 37% 29% 6%	760
	21st to end	Night	8% 7% 18% 33% 28% 6%	760
October	1st to 10th	Night	8% 9% 24% 33% 22% 3	760
	11th to 20th	Night	6% 9% 25% 37% 19% 4	760
	21st to end	Night	9% 12% 25% 35% 17% 3	836
November	1st to 10th	Night	9% 11% 28% 33% 17% 2	780
	11th to 20th	Night	9% 14% 30% 32% 12% 3	800
	21st to end	Night	9% 14% 28% 34% 12% 3	981
December	1st to 10th	Night	9% 12% 34% 33% 11% 1	1000
	11th to 20th	Night	10% 14% 35% 32% 9% 1	1000
	21st to end	Night	14% 14% 37% 27% 7% 1	980

Page generated at 2025-03-24 07:04:26. Version ac07

Copyright © 2025 Attilla Danko.