Solis Lacus Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Solis Lacus Observatory clear sky chart from 2005-11-06 to 2024-11-04.

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	16% 11% 4 8% 5% 5% 5% 4 6% 7% 30%	101491
	Night	16% 11% 4 9% 5% 4 4 4 5% 6% 31%	97525
Transparency	Day	53% 3 11% 21% 10% 1	105039
	Night	54% 3 11% 21% 10% 1	102066
Seeing	Day	26% 13% 28% 19% 10% 4	14757
	Night	24% 12% 26% 27% 10% 1	23960

By Month

Percentage Cloud Cover NE (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	13% 18% 10% 13% 5% 4 5% 3 3 5% 22%	2517
	11th to 20th	Day	14% 15% 8% 16% 6% 7% 5% 3 4 5% 18%	2520
	21st to end	Day	17% 18% 9% 12% 9% 5% 4 3 4 4 16%	3123
February	1st to 10th	Day	16% 15% 5% 13% 7% 6% 5% 4 5% 5% 19%	1710
	11th to 20th	Day	12% 14% 6% 13% 8% 5% 6% 4 5% 5% 22%	1724
	21st to end	Day	19% 12% 3 11% 9% 5% 4 3 4 5% 24%	1570
March	1st to 10th	Day	23% 15% 6% 10% 5% 4 3 2 3 4 25%	3171
	11th to 20th	Day	11% 17% 5% 10% 6% 4 4 3 5% 6% 28%	3480
	21st to end	Day	18% 12% 4 10% 6% 4 4 4 4 5% 30%	3999
April	1st to 10th	Day	18% 14% 3 7% 5% 4 4 3 5% 6% 30%	2280
	11th to 20th	Day	17% 10% 3 8% 6% 4 5% 4 4 6% 33%	2254
	21st to end	Day	18% 11% 3 8% 5% 4 3 3 3 7% 33%	2280
May	1st to 10th	Day	25% 9% 3 6% 4 4 4 3 5% 6% 32%	4317
	11th to 20th	Day	20% 9% 3 8% 5% 6% 5% 4 7% 7% 26%	4398
	21st to end	Day	12% 6% 2 7% 5% 4 5% 4 7% 9% 40%	4837
June	1st to 10th	Day	18% 7% 3 6% 5% 5% 5% 4 6% 9% 32%	2660
	11th to 20th	Day	15% 7% 2 5% 5% 6% 5% 5% 7% 9% 34%	2660
	21st to end	Day	14% 8% 2 6% 5% 5% 7% 4 6% 10% 34%	2660
July	1st to 10th	Day	9% 6% 2 7% 5% 5% 6% 5% 9% 12% 34%	4440
	11th to 20th	Day	8% 5% 2 7% 6% 6% 6% 5% 8% 11% 35%	4440
	21st to end	Day	12% 7% 2 7% 6% 6% 6% 5% 8% 8% 32%	4814
August	1st to 10th	Day	18% 8% 3 8% 4 5% 5% 5% 7% 7% 30%	4105
	11th to 20th	Day	15% 8% 3 7% 4 6% 6% 5% 8% 10% 28%	3885
	21st to end	Day	14% 8% 3 6% 4 5% 5% 4 6% 8% 37%	4180
September	1st to 10th	Day	16% 8% 2 6% 4 4 4 4 6% 8% 38%	2280
	11th to 20th	Day	13% 7% 3 6% 4 4 4 4 5% 6% 44%	2280
	21st to end	Day	18% 8% 3 7% 4 5% 4 4 6% 7% 34%	2033
October	1st to 10th	Day	17% 8% 4 8% 5% 5% 4 3 6% 8% 33%	1900
	11th to 20th	Day	18% 8% 3 8% 5% 5% 4 3 5% 6% 33%	1900
	21st to end	Day	22% 13% 4 8% 5% 4 4 3 5% 7% 27%	2014
November	1st to 10th	Day	14% 11% 3 8% 5% 4 4 3 4 7% 37%	1698
	11th to 20th	Day	15% 15% 4 9% 6% 4 5% 3 4 5% 30%	1644
	21st to end	Day	17% 15% 4 10% 6% 4 4 4 5% 7% 23%	1520
December	1st to 10th	Day	17% 17% 7% 10% 6% 5% 6% 4 4 6% 18%	1520
	11th to 20th	Day	20% 15% 8% 11% 4 4 3 2 4 5% 24%	1906
	21st to end	Day	24% 19% 7% 12% 6% 4 4 3 3 4 14%	2772
January	1st to 10th	Night	15% 15% 7% 15% 6% 4 4 4 5% 5% 19%	4429
	11th to 20th	Night	12% 15% 7% 14% 8% 6% 5% 3 5% 6% 20%	4440
	21st to end	Night	22% 15% 6% 14% 9% 5% 4 3 3 4 16%	4532
February	1st to 10th	Night	15% 12% 5% 10% 8% 6% 6% 4 6% 5% 24%	2470
	11th to 20th	Night	13% 14% 5% 14% 7% 6% 6% 4 5% 5% 21%	2342
	21st to end	Night	19% 11% 4 13% 6% 4 5% 3 5% 6% 25%	1884
March	1st to 10th	Night	20% 13% 5% 9% 5% 4 3 3 4 4 28%	3665
	11th to 20th	Night	13% 18% 5% 9% 6% 4 4 3 5% 5% 28%	3479
	21st to end	Night	15% 14% 3 9% 5% 5% 4 4 4 5% 31%	3631
April	1st to 10th	Night	20% 12% 3 8% 4 5% 4 4 4 7% 30%	1900
	11th to 20th	Night	20% 10% 3 7% 5% 2 3 4 4 6% 35%	1875
	21st to end	Night	18% 9% 3 6% 4 4 5% 2 5% 5% 37%	1900
May	1st to 10th	Night	26% 9% 2 7% 5% 4 4 3 4 6% 31%	2637
	11th to 20th	Night	17% 10% 3 7% 4 4 4 4 6% 7% 32%	2495
	21st to end	Night	11% 8% 3 8% 5% 5% 5% 4 6% 7% 38%	2738
June	1st to 10th	Night	16% 8% 2 6% 4 3 3 4 6% 8% 39%	1520
	11th to 20th	Night	15% 6% 2 5% 5% 4 5% 4 7% 8% 40%	1520
	21st to end	Night	11% 5% 2 6% 5% 4 5% 5% 6% 8% 43%	1520
July	1st to 10th	Night	8% 7% 3 8% 6% 5% 5% 3 6% 8% 40%	2520
	11th to 20th	Night	10% 6% 2 7% 4 5% 4 4 7% 10% 42%	2520
	21st to end	Night	13% 7% 3 7% 5% 4 5% 4 6% 7% 39%	2739
August	1st to 10th	Night	18% 7% 3 8% 5% 4 4 4 6% 7% 35%	2820
	11th to 20th	Night	14% 8% 3 7% 5% 5% 4 3 5% 6% 40%	2911
	21st to end	Night	11% 8% 2 6% 4 4 5% 4 5% 8% 43%	3476
September	1st to 10th	Night	15% 5% 2 6% 4 4 4 4 6% 7% 43%	1900
	11th to 20th	Night	12% 6% 2 5% 3 4 4 3 5% 7% 49%	1900
	21st to end	Night	17% 7% 3 6% 5% 4 4 4 5% 7% 38%	2142
October	1st to 10th	Night	16% 8% 3 9% 5% 4 4 4 5% 7% 36%	2280
	11th to 20th	Night	19% 8% 3 7% 4 4 4 3 5% 6% 37%	2280
	21st to end	Night	22% 13% 3 8% 5% 4 3 2 5% 7% 28%	2584
November	1st to 10th	Night	12% 11% 3 8% 5% 4 4 3 4 6% 38%	2453
	11th to 20th	Night	18% 11% 3 7% 5% 5% 5% 4 5% 6% 32%	2531
	21st to end	Night	14% 14% 5% 8% 5% 5% 5% 4 7% 7% 27%	2660
December	1st to 10th	Night	17% 16% 6% 11% 6% 4 4 4 5% 6% 20%	2660
	11th to 20th	Night	19% 14% 5% 10% 6% 4 5% 4 5% 5% 22%	3288
	21st to end	Night	25% 16% 6% 10% 4 4 4 3 4 5% 18%	4884

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	69% 1 8% 16% 5% 1	2518
	11th to 20th	Day	71% 2 8% 13% 5% 1	2520
	21st to end	Day	73% 2 9% 11% 5%	3123
February	1st to 10th	Day	68% 3 8% 14% 6% 1	1710
	11th to 20th	Day	64% 3 6% 19% 6%	1733
	21st to end	Day	63% 3 8% 17% 8% 1	1570
March	1st to 10th	Day	66% 1 8% 17% 7% 1	3174
	11th to 20th	Day	59% 1 11% 18% 9% 2	3480
	21st to end	Day	58% 1 7% 18% 15% 1	3999
April	1st to 10th	Day	56% 3 6% 23% 10% 2	2280
	11th to 20th	Day	53% 3 9% 19% 14% 2	2254
	21st to end	Day	54% 2 7% 21% 13% 3	2280
May	1st to 10th	Day	55% 2 10% 20% 11% 2	4331
	11th to 20th	Day	57% 2 10% 22% 7% 1	4402
	21st to end	Day	42% 2 11% 28% 16% 1	4837
June	1st to 10th	Day	49% 4 11% 22% 14% 1	2660
	11th to 20th	Day	46% 4 13% 25% 11% 1	2660
	21st to end	Day	45% 5% 12% 25% 11% 1	2660
July	1st to 10th	Day	40% 7% 18% 25% 10% 1	4370
	11th to 20th	Day	39% 6% 17% 27% 10%	4365
	21st to end	Day	47% 5% 14% 22% 11% 1	4661
August	1st to 10th	Day	52% 5% 13% 19% 10%	4091
	11th to 20th	Day	47% 6% 16% 24% 7%	3924
	21st to end	Day	45% 4 10% 32% 8% 1	4180
September	1st to 10th	Day	45% 4 10% 26% 14% 1	2280
	11th to 20th	Day	41% 3 11% 24% 20% 1	2280
	21st to end	Day	50% 3 11% 23% 12% 2	2033
October	1st to 10th	Day	47% 4 10% 24% 14% 1	3160
	11th to 20th	Day	46% 3 12% 23% 15% 1	3140
	21st to end	Day	42% 4 16% 27% 11% 1	3304
November	1st to 10th	Day	48% 3 11% 22% 13% 2	1698
	11th to 20th	Day	58% 2 10% 19% 10% 2	1644
	21st to end	Day	62% 3 13% 17% 6% 1	1520
December	1st to 10th	Day	69% 2 11% 13% 5%	1520
	11th to 20th	Day	66% 3 14% 13% 4	1906
	21st to end	Day	76% 2 6% 12% 3	2772
January	1st to 10th	Night	68% 2 11% 13% 5%	4429
	11th to 20th	Night	67% 2 10% 15% 5%	4440
	21st to end	Night	75% 2 6% 12% 4 1	4532
February	1st to 10th	Night	62% 3 11% 15% 8%	2470
	11th to 20th	Night	65% 3 9% 15% 7% 1	2344
	21st to end	Night	60% 2 9% 18% 9% 1	1884
March	1st to 10th	Night	61% 2 9% 19% 9%	3675
	11th to 20th	Night	60% 1 11% 21% 6%	3480
	21st to end	Night	57% 2 5% 20% 13% 2	3631
April	1st to 10th	Night	56% 2 9% 20% 11% 2	1900
	11th to 20th	Night	51% 2 11% 20% 16%	1875
	21st to end	Night	50% 2 10% 22% 14% 3	1900
May	1st to 10th	Night	57% 2 8% 21% 9% 2	2643
	11th to 20th	Night	51% 3 15% 21% 9% 1	2496
	21st to end	Night	46% 2 12% 22% 16% 1	2739
June	1st to 10th	Night	43% 3 12% 26% 16%	1520
	11th to 20th	Night	41% 4 16% 26% 11% 2	1520
	21st to end	Night	39% 4 14% 29% 13% 1	1520
July	1st to 10th	Night	42% 5% 15% 21% 15% 1	2480
	11th to 20th	Night	37% 5% 16% 27% 15%	2472
	21st to end	Night	44% 5% 12% 23% 16% 1	2651
August	1st to 10th	Night	50% 6% 15% 22% 8%	2810
	11th to 20th	Night	46% 4 14% 26% 9%	2938
	21st to end	Night	40% 4 12% 32% 11% 1	3476
September	1st to 10th	Night	41% 4 12% 26% 15% 1	1900
	11th to 20th	Night	36% 3 11% 31% 19% 1	1900
	21st to end	Night	47% 3 10% 24% 15% 1	2142
October	1st to 10th	Night	52% 4 10% 23% 10% 1	3800
	11th to 20th	Night	44% 3 14% 21% 15% 3	3779
	21st to end	Night	44% 3 15% 27% 10%	4244
November	1st to 10th	Night	47% 3 11% 21% 15% 2	2453
	11th to 20th	Night	54% 2 11% 21% 11% 2	2531
	21st to end	Night	55% 3 15% 21% 6%	2660
December	1st to 10th	Night	66% 3 11% 16% 4	2660
	11th to 20th	Night	64% 3 10% 16% 6%	3288
	21st to end	Night	70% 2 10% 15% 2	4884

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	30% 18% 33% 16% 3 1	180
	11th to 20th	Day	42% 21% 24% 11% 3	180
	21st to end	Day	26% 26% 30% 14% 4 1	297
February	1st to 10th	Day	29% 27% 35% 9%	270
	11th to 20th	Day	37% 27% 28% 7% 1	331
	21st to end	Day	37% 21% 27% 11% 3	382
March	1st to 10th	Day	34% 18% 29% 14% 4 1	460
	11th to 20th	Day	35% 19% 27% 13% 5% 1	460
	21st to end	Day	34% 21% 26% 12% 3 2	506
April	1st to 10th	Day	37% 16% 28% 14% 4 1	460
	11th to 20th	Day	31% 22% 26% 12% 6% 4	452
	21st to end	Day	34% 16% 29% 13% 7% 2	460
May	1st to 10th	Day	34% 13% 27% 14% 9% 3	463
	11th to 20th	Day	24% 12% 30% 22% 8% 4	487
	21st to end	Day	19% 9% 31% 23% 14% 4	529
June	1st to 10th	Day	23% 10% 31% 21% 13% 2	490
	11th to 20th	Day	20% 10% 26% 29% 13% 3	490
	21st to end	Day	21% 9% 33% 24% 11% 2	490
July	1st to 10th	Day	16% 4 29% 28% 17% 6%	485
	11th to 20th	Day	12% 7% 26% 31% 18% 5%	484
	21st to end	Day	15% 6% 36% 26% 13% 4	532
August	1st to 10th	Day	16% 6% 24% 26% 21% 7%	486
	11th to 20th	Day	19% 5% 23% 29% 16% 9%	479
	21st to end	Day	13% 7% 27% 27% 15% 11%	539
September	1st to 10th	Day	20% 11% 22% 20% 18% 8%	490
	11th to 20th	Day	15% 5% 23% 25% 19% 12%	490
	21st to end	Day	24% 11% 27% 20% 13% 6%	490
October	1st to 10th	Day	26% 10% 23% 20% 14% 7%	490
	11th to 20th	Day	26% 15% 27% 20% 9% 2	490
	21st to end	Day	34% 12% 29% 18% 8%	499
November	1st to 10th	Day	28% 15% 21% 23% 11% 2	374
	11th to 20th	Day	33% 18% 24% 15% 9% 1	304
	21st to end	Day	37% 17% 33% 11% 3	180
December	1st to 10th	Day	33% 22% 31% 9% 3 2	180
	11th to 20th	Day	34% 18% 28% 17% 3	180
	21st to end	Day	38% 20% 30% 11% 2 1	198
January	1st to 10th	Night	27% 21% 31% 18% 2	760
	11th to 20th	Night	29% 17% 27% 23% 4	760
	21st to end	Night	21% 20% 35% 20% 3	836
February	1st to 10th	Night	28% 17% 31% 22% 2	760
	11th to 20th	Night	27% 20% 34% 17% 2	743
	21st to end	Night	34% 15% 29% 18% 4	628
March	1st to 10th	Night	28% 19% 28% 21% 4	760
	11th to 20th	Night	28% 18% 31% 18% 5%	760
	21st to end	Night	26% 19% 28% 20% 6% 1	836
April	1st to 10th	Night	30% 15% 30% 23% 3	760
	11th to 20th	Night	28% 14% 30% 20% 7% 1	751
	21st to end	Night	25% 14% 27% 26% 7%	760
May	1st to 10th	Night	30% 6% 23% 31% 11%	464
	11th to 20th	Night	19% 9% 30% 32% 9% 1	374
	21st to end	Night	14% 5% 27% 37% 15% 1	411
June	1st to 10th	Night	19% 7% 22% 38% 13% 1	380
	11th to 20th	Night	19% 5% 21% 39% 15% 1	380
	21st to end	Night	14% 4 28% 42% 12% 1	380
July	1st to 10th	Night	11% 3 19% 46% 19% 2	370
	11th to 20th	Night	11% 2 17% 46% 21% 1	368
	21st to end	Night	15% 2 19% 46% 18% 1	416
August	1st to 10th	Night	13% 1 21% 37% 26% 2	562
	11th to 20th	Night	16% 3 13% 35% 29% 5%	638
	21st to end	Night	15% 3 16% 37% 26% 2	836
September	1st to 10th	Night	19% 4 23% 33% 19% 3	760
	11th to 20th	Night	17% 4 16% 32% 26% 5%	760
	21st to end	Night	21% 8% 23% 28% 19% 2	760
October	1st to 10th	Night	23% 8% 22% 27% 18% 2	760
	11th to 20th	Night	24% 10% 25% 31% 9% 1	760
	21st to end	Night	32% 10% 28% 24% 6%	836
November	1st to 10th	Night	21% 12% 28% 30% 9% 1	755
	11th to 20th	Night	27% 14% 30% 21% 7% 1	760
	21st to end	Night	25% 15% 32% 21% 6% 1	760
December	1st to 10th	Night	30% 18% 28% 19% 4	760
	11th to 20th	Night	27% 19% 29% 21% 3	760
	21st to end	Night	30% 17% 32% 18% 3	836

Page generated at 2024-11-01 22:47:29. Version ac07

Copyright © 2024 Attilla Danko.