Lubbock
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lubbock clear sky chart from 2005-11-06 to 2025-08-05.

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	6% 4 1 4 3 3 3 3 5% 6% 62%	129597
	Night	5% 4 1 4 3 3 3 3 5% 7% 64%	127381
Transparency	Day	24% 3 7% 21% 28% 18%	129324
	Night	22% 3 7% 21% 28% 20%	127170
Seeing	Day	8% 8% 27% 32% 21% 5%	16179
	Night	7% 7% 34% 37% 14% 1	26100

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	8% 6% 2 6% 3 3 3 3 4 4 56%	4077
	11th to 20th	Day	2 4 1 3 2 2 2 3 3 5% 72%	4287
	21st to end	Day	7% 5% 2 5% 4 4 4 4 5% 6% 55%	4994
February	1st to 10th	Day	6% 6% 1 3 3 2 3 2 4 6% 63%	2000
	11th to 20th	Day	7% 4 2 5% 4 3 3 3 4 7% 57%	1949
	21st to end	Day	6% 7% 2 5% 4 3 2 2 4 5% 62%	1650
March	1st to 10th	Day	5% 5% 2 5% 2 3 3 2 3 6% 64%	4500
	11th to 20th	Day	9% 4 1 4 3 3 3 3 5% 7% 57%	4776
	21st to end	Day	2 3 1 4 3 3 4 4 6% 8% 60%	5728
April	1st to 10th	Day	6% 3 1 3 3 3 3 3 4 6% 66%	2400
	11th to 20th	Day	8% 5% 2 4 3 3 4 3 4 5% 60%	2371
	21st to end	Day	4 3 2 4 3 3 3 3 5% 5% 66%	2400
May	1st to 10th	Day	11% 4 1 4 3 3 3 3 4 5% 59%	5802
	11th to 20th	Day	9% 4 1 3 2 3 3 2 4 5% 64%	5862
	21st to end	Day	9% 5% 2 4 3 3 3 3 5% 7% 56%	6446
June	1st to 10th	Day	4 4 1 4 4 3 4 3 6% 8% 60%	2600
	11th to 20th	Day	4 3 1 3 3 3 4 3 5% 6% 65%	2600
	21st to end	Day	3 4 2 3 4 3 4 4 6% 7% 62%	2600
July	1st to 10th	Day	10% 5% 2 6% 4 4 5% 4 6% 8% 47%	5899
	11th to 20th	Day	4 3 1 4 3 3 4 3 5% 8% 62%	5900
	21st to end	Day	3 2 1 3 3 3 4 3 7% 10% 60%	6252
August	1st to 10th	Day	1 1 1 3 2 3 3 3 5% 8% 69%	3833
	11th to 20th	Day	4 2 1 2 2 3 4 3 5% 8% 66%	3726
	21st to end	Day	6% 4 1 4 3 3 3 3 6% 7% 60%	4180
September	1st to 10th	Day	8% 4 2 6% 3 4 4 4 5% 8% 52%	2256
	11th to 20th	Day	10% 4 2 6% 4 4 4 3 5% 8% 50%	2090
	21st to end	Day	9% 3 1 4 2 3 3 2 5% 6% 63%	2090
October	1st to 10th	Day	5% 2 1 3 2 2 1 1 2 4 77%	3480
	11th to 20th	Day	12% 4 2 4 2 2 2 2 3 4 65%	3458
	21st to end	Day	5% 3 1 2 1 1 2 2 3 5% 74%	3209
November	1st to 10th	Day	6% 3 1 3 2 2 3 2 5% 6% 66%	1763
	11th to 20th	Day	3 3 1 4 3 2 3 3 5% 5% 69%	1800
	21st to end	Day	9% 4 2 3 2 3 3 3 5% 6% 61%	1800
December	1st to 10th	Day	7% 5% 2 5% 3 3 3 3 4 6% 58%	2940
	11th to 20th	Day	4 3 1 4 3 4 3 2 4 5% 67%	3391
	21st to end	Day	5% 5% 2 4 2 2 2 2 3 4 69%	4488
January	1st to 10th	Night	5% 7% 2 5% 3 3 3 3 5% 6% 59%	5888
	11th to 20th	Night	2 2 1 3 2 2 2 2 4 6% 73%	5736
	21st to end	Night	6% 7% 2 4 3 3 3 3 5% 7% 56%	5984
February	1st to 10th	Night	6% 5% 2 4 3 2 3 3 4 5% 64%	2400
	11th to 20th	Night	6% 5% 2 5% 3 3 3 3 4 6% 60%	2338
	21st to end	Night	6% 4 1 3 3 3 4 3 5% 5% 62%	1980
March	1st to 10th	Night	4 5% 2 4 3 3 3 2 4 5% 66%	5374
	11th to 20th	Night	6% 3 1 3 3 2 3 3 4 6% 65%	5192
	21st to end	Night	2 3 1 4 3 3 4 3 5% 8% 63%	5211
April	1st to 10th	Night	6% 4 1 3 3 3 3 3 4 6% 65%	2000
	11th to 20th	Night	7% 3 1 4 3 3 3 3 4 7% 62%	1977
	21st to end	Night	5% 3 1 3 3 2 3 3 4 7% 66%	2000
May	1st to 10th	Night	9% 4 1 3 2 2 3 2 4 5% 65%	4177
	11th to 20th	Night	5% 3 1 3 2 2 4 3 4 5% 66%	4053
	21st to end	Night	8% 4 1 4 3 3 3 3 5% 6% 61%	4451
June	1st to 10th	Night	4 3 2 4 3 3 3 3 8% 12% 56%	1800
	11th to 20th	Night	2 2 1 2 3 3 4 4 6% 9% 63%	1800
	21st to end	Night	3 3 1 4 3 3 4 4 8% 9% 61%	1800
July	1st to 10th	Night	6% 5% 2 5% 4 4 4 5% 7% 10% 46%	4080
	11th to 20th	Night	3 2 1 4 3 3 3 4 7% 12% 60%	4080
	21st to end	Night	2 2 1 3 2 3 4 4 6% 12% 60%	4617
August	1st to 10th	Night	2 2 1 3 2 2 3 3 7% 11% 64%	3195
	11th to 20th	Night	2 3 2 4 3 3 4 4 6% 8% 62%	3113
	21st to end	Night	3 2 1 3 3 3 3 3 5% 10% 64%	3487
September	1st to 10th	Night	8% 4 1 5% 4 3 4 3 5% 8% 55%	1924
	11th to 20th	Night	8% 4 2 4 3 4 4 4 5% 8% 54%	2090
	21st to end	Night	7% 3 1 5% 2 3 3 2 4 6% 65%	2090
October	1st to 10th	Night	3 2 3 2 2 2 2 2 4 78%	3480
	11th to 20th	Night	11% 4 1 3 2 2 2 2 4 5% 65%	3460
	21st to end	Night	5% 2 1 1 1 1 2 2 3 5% 76%	4313
November	1st to 10th	Night	6% 3 1 2 2 2 2 2 4 6% 71%	2535
	11th to 20th	Night	2 3 1 3 2 2 3 3 5% 6% 71%	2600
	21st to end	Night	7% 5% 1 3 2 3 3 3 5% 7% 62%	2600
December	1st to 10th	Night	6% 5% 2 4 4 3 3 3 4 6% 60%	4250
	11th to 20th	Night	4 4 1 4 2 2 3 2 4 6% 67%	4816
	21st to end	Night	3 5% 2 4 3 3 3 2 4 5% 66%	6490

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	32% 2 4 19% 29% 13%	4078
	11th to 20th	Day	17% 1 4 20% 37% 21%	4287
	21st to end	Day	31% 2 4 17% 30% 16%	4994
February	1st to 10th	Day	24% 2 5% 18% 29% 22%	2000
	11th to 20th	Day	28% 3 5% 21% 24% 19%	1959
	21st to end	Day	28% 2 2 11% 35% 23%	1650
March	1st to 10th	Day	24% 2 2 8% 28% 36%	4500
	11th to 20th	Day	28% 2 5% 14% 26% 26%	4776
	21st to end	Day	22% 2 5% 20% 30% 20%	5728
April	1st to 10th	Day	21% 3 5% 16% 30% 24%	2400
	11th to 20th	Day	26% 3 5% 15% 26% 24%	2374
	21st to end	Day	20% 2 7% 21% 31% 18%	2400
May	1st to 10th	Day	29% 2 7% 18% 24% 21%	5802
	11th to 20th	Day	24% 2 5% 15% 22% 32%	5866
	21st to end	Day	28% 3 9% 19% 16% 25%	6447
June	1st to 10th	Day	22% 4 15% 28% 21% 10%	2600
	11th to 20th	Day	19% 4 8% 21% 30% 17%	2600
	21st to end	Day	21% 4 11% 26% 25% 12%	2600
July	1st to 10th	Day	35% 5% 11% 23% 22% 5%	5836
	11th to 20th	Day	21% 3 12% 35% 26% 4	5831
	21st to end	Day	19% 4 18% 31% 25% 4	6071
August	1st to 10th	Day	14% 4 10% 29% 34% 10%	3821
	11th to 20th	Day	17% 4 10% 28% 32% 9%	3762
	21st to end	Day	23% 5% 12% 26% 27% 7%	4179
September	1st to 10th	Day	30% 5% 11% 20% 23% 12%	2256
	11th to 20th	Day	32% 5% 8% 23% 24% 7%	2090
	21st to end	Day	24% 2 6% 19% 34% 13%	2090
October	1st to 10th	Day	15% 2 5% 13% 29% 36%	3480
	11th to 20th	Day	26% 2 6% 16% 26% 24%	3458
	21st to end	Day	16% 2 2 22% 37% 22%	3209
November	1st to 10th	Day	20% 3 7% 17% 31% 23%	1763
	11th to 20th	Day	19% 2 5% 20% 36% 19%	1800
	21st to end	Day	25% 2 4 17% 31% 21%	1800
December	1st to 10th	Day	28% 2 4 24% 28% 13%	2940
	11th to 20th	Day	22% 2 5% 16% 35% 20%	3389
	21st to end	Day	22% 1 3 20% 36% 16%	4488
January	1st to 10th	Night	29% 2 3 26% 30% 11%	5888
	11th to 20th	Night	14% 1 8% 21% 36% 19%	5736
	21st to end	Night	29% 2 6% 18% 27% 18%	5984
February	1st to 10th	Night	25% 2 5% 15% 29% 24%	2400
	11th to 20th	Night	27% 3 6% 20% 24% 21%	2338
	21st to end	Night	24% 3 4 13% 25% 31%	1980
March	1st to 10th	Night	22% 2 2 10% 24% 39%	5374
	11th to 20th	Night	22% 2 5% 16% 17% 39%	5192
	21st to end	Night	20% 2 7% 19% 29% 23%	5211
April	1st to 10th	Night	22% 3 7% 15% 27% 27%	2000
	11th to 20th	Night	23% 3 8% 16% 26% 24%	1977
	21st to end	Night	20% 3 9% 21% 27% 20%	2000
May	1st to 10th	Night	24% 2 9% 24% 18% 22%	4175
	11th to 20th	Night	21% 2 8% 14% 22% 33%	4054
	21st to end	Night	26% 3 10% 17% 13% 31%	4452
June	1st to 10th	Night	21% 5% 16% 30% 18% 10%	1800
	11th to 20th	Night	16% 5% 12% 23% 27% 17%	1800
	21st to end	Night	19% 4 14% 28% 21% 14%	1800
July	1st to 10th	Night	32% 4 13% 33% 15% 2	4035
	11th to 20th	Night	18% 3 13% 35% 26% 4	4026
	21st to end	Night	18% 4 16% 30% 29% 4	4485
August	1st to 10th	Night	15% 4 8% 29% 34% 11%	3184
	11th to 20th	Night	20% 4 9% 25% 33% 9%	3143
	21st to end	Night	18% 4 16% 28% 28% 7%	3487
September	1st to 10th	Night	29% 5% 10% 20% 25% 12%	1924
	11th to 20th	Night	28% 5% 12% 20% 27% 8%	2090
	21st to end	Night	23% 3 6% 21% 29% 18%	2090
October	1st to 10th	Night	14% 2 5% 13% 23% 43%	3480
	11th to 20th	Night	24% 2 5% 19% 25% 25%	3460
	21st to end	Night	13% 2 4 20% 36% 25%	4313
November	1st to 10th	Night	17% 2 6% 21% 33% 22%	2535
	11th to 20th	Night	16% 3 5% 19% 37% 21%	2600
	21st to end	Night	23% 2 5% 17% 33% 20%	2600
December	1st to 10th	Night	27% 2 5% 20% 32% 14%	4250
	11th to 20th	Night	20% 1 3 15% 40% 22%	4817
	21st to end	Night	23% 2 3 21% 36% 16%	6490

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	14% 13% 36% 27% 9% 2	300
	11th to 20th	Day	13% 15% 35% 26% 9% 1	300
	21st to end	Day	8% 13% 39% 28% 11% 1	330
February	1st to 10th	Day	10% 13% 38% 31% 6% 1	300
	11th to 20th	Day	11% 15% 44% 21% 8% 1	300
	21st to end	Day	12% 16% 46% 21% 4 1	249
March	1st to 10th	Day	11% 12% 44% 27% 6%	300
	11th to 20th	Day	19% 12% 33% 25% 9% 1	300
	21st to end	Day	8% 16% 44% 25% 6%	439
April	1st to 10th	Day	9% 19% 44% 23% 5%	500
	11th to 20th	Day	13% 14% 47% 21% 5% 1	492
	21st to end	Day	7% 17% 39% 30% 6% 1	500
May	1st to 10th	Day	7% 11% 42% 31% 8% 1	657
	11th to 20th	Day	12% 10% 31% 29% 15% 3	725
	21st to end	Day	8% 8% 36% 32% 14% 2	789
June	1st to 10th	Day	5% 4 22% 45% 20% 4	730
	11th to 20th	Day	4 4 27% 43% 19% 3	730
	21st to end	Day	3 2 19% 42% 30% 5%	730
July	1st to 10th	Day	7% 2 9% 34% 36% 12%	721
	11th to 20th	Day	3 7% 38% 40% 12%	718
	21st to end	Day	2 1 6% 33% 43% 13%	723
August	1st to 10th	Day	2 1 9% 37% 42% 9%	504
	11th to 20th	Day	6% 1 8% 35% 37% 12%	477
	21st to end	Day	5% 1 7% 33% 39% 16%	539
September	1st to 10th	Day	6% 1 9% 38% 34% 12%	466
	11th to 20th	Day	3 1 11% 37% 38% 11%	300
	21st to end	Day	12% 3 11% 34% 33% 8%	300
October	1st to 10th	Day	10% 2 21% 32% 30% 5%	300
	11th to 20th	Day	8% 7% 25% 37% 21% 3	300
	21st to end	Day	16% 9% 25% 27% 19% 4	330
November	1st to 10th	Day	13% 9% 30% 32% 13% 3	300
	11th to 20th	Day	6% 13% 27% 34% 15% 5%	300
	21st to end	Day	13% 16% 34% 24% 10% 2	300
December	1st to 10th	Day	11% 13% 36% 28% 12% 1	300
	11th to 20th	Day	8% 11% 36% 37% 7%	300
	21st to end	Day	12% 16% 42% 23% 7% 1	330
January	1st to 10th	Night	10% 8% 39% 34% 9%	1000
	11th to 20th	Night	8% 8% 38% 36% 9% 1	927
	21st to end	Night	6% 9% 41% 35% 8%	880
February	1st to 10th	Night	8% 11% 44% 30% 7% 1	800
	11th to 20th	Night	10% 11% 44% 29% 6%	784
	21st to end	Night	9% 15% 45% 29% 2	660
March	1st to 10th	Night	9% 13% 44% 29% 5%	800
	11th to 20th	Night	12% 15% 40% 28% 6%	695
	21st to end	Night	7% 16% 45% 28% 4	660
April	1st to 10th	Night	8% 13% 48% 29% 3	600
	11th to 20th	Night	8% 14% 52% 25% 2	593
	21st to end	Night	7% 11% 51% 27% 4	600
May	1st to 10th	Night	6% 9% 48% 33% 4	600
	11th to 20th	Night	8% 8% 39% 32% 12% 1	591
	21st to end	Night	7% 8% 43% 34% 8%	650
June	1st to 10th	Night	4 4 38% 43% 11%	600
	11th to 20th	Night	3 3 43% 42% 9%	600
	21st to end	Night	3 2 30% 44% 21% 1	600
July	1st to 10th	Night	5% 15% 47% 30% 2	585
	11th to 20th	Night	3 1 15% 48% 31% 2	582
	21st to end	Night	2 1 9% 46% 40% 2	657
August	1st to 10th	Night	2 1 11% 47% 38% 2	579
	11th to 20th	Night	4 1 11% 44% 37% 2	564
	21st to end	Night	3 1 9% 46% 38% 3	627
September	1st to 10th	Night	8% 1 10% 47% 32% 2	570
	11th to 20th	Night	9% 3 15% 47% 25% 1	570
	21st to end	Night	7% 2 20% 44% 24% 2	570
October	1st to 10th	Night	5% 3 27% 46% 17% 1	570
	11th to 20th	Night	11% 6% 31% 40% 12% 1	570
	21st to end	Night	9% 7% 30% 33% 20% 1	941
November	1st to 10th	Night	8% 6% 30% 40% 15% 1	975
	11th to 20th	Night	4 8% 33% 39% 14% 1	1000
	21st to end	Night	11% 8% 32% 36% 12% 1	1000
December	1st to 10th	Night	10% 8% 36% 37% 9% 1	1000
	11th to 20th	Night	9% 9% 42% 33% 7%	1000
	21st to end	Night	9% 11% 37% 34% 9%	1100

Page generated at 2025-08-02 00:32:25. Version ac07

Copyright © 2025 Attilla Danko.