Lake Charles
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lake Charles clear sky chart from 2005-11-06 to 2025-10-19.

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	12% 7% 3 7% 5% 5% 5% 4 6% 8% 38%	126147
	Night	13% 7% 2 6% 4 4 4 3 5% 7% 44%	123756
Transparency	Day	41% 5% 12% 19% 16% 7%	129754
	Night	38% 4 12% 19% 18% 8%	128226
Seeing	Day	12% 7% 20% 26% 24% 12%	16176
	Night	14% 5% 20% 31% 25% 5%	25883

By Month

Percentage Cloud Cover SE (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	20% 9% 3 6% 3 4 3 2 4 5% 41%	4077
	11th to 20th	Day	14% 7% 2 6% 3 4 3 2 4 5% 51%	4080
	21st to end	Day	24% 10% 3 7% 3 3 3 2 4 6% 34%	4488
February	1st to 10th	Day	19% 8% 3 8% 5% 4 3 3 5% 6% 36%	1809
	11th to 20th	Day	20% 10% 3 7% 4 4 3 3 4 6% 37%	2017
	21st to end	Day	21% 11% 3 7% 4 3 4 3 4 5% 35%	1815
March	1st to 10th	Day	21% 9% 3 7% 4 4 4 4 5% 6% 32%	4936
	11th to 20th	Day	14% 7% 2 7% 4 4 4 4 5% 6% 42%	4980
	21st to end	Day	16% 9% 3 7% 5% 4 4 3 5% 6% 39%	5462
April	1st to 10th	Day	12% 7% 3 7% 6% 5% 5% 3 5% 7% 39%	2310
	11th to 20th	Day	15% 7% 2 6% 5% 4 4 3 7% 9% 38%	2374
	21st to end	Day	9% 7% 2 5% 5% 5% 5% 4 7% 9% 43%	2400
May	1st to 10th	Day	16% 9% 3 8% 6% 6% 5% 4 6% 8% 29%	5405
	11th to 20th	Day	9% 6% 2 6% 4 4 5% 5% 6% 9% 43%	5404
	21st to end	Day	7% 5% 2 7% 6% 6% 7% 5% 8% 11% 35%	6422
June	1st to 10th	Day	7% 6% 2 8% 5% 6% 7% 5% 9% 10% 36%	2600
	11th to 20th	Day	4 6% 2 7% 6% 6% 7% 6% 9% 10% 36%	2600
	21st to end	Day	7% 6% 3 7% 6% 7% 9% 7% 10% 12% 26%	2600
July	1st to 10th	Day	6% 6% 3 8% 6% 7% 8% 6% 10% 12% 28%	5900
	11th to 20th	Day	6% 6% 3 10% 7% 7% 8% 6% 8% 12% 27%	5900
	21st to end	Day	10% 7% 3 8% 6% 5% 6% 5% 8% 11% 31%	6422
August	1st to 10th	Day	3 2 1 4 4 5% 6% 5% 7% 10% 54%	4086
	11th to 20th	Day	3 3 2 5% 5% 6% 7% 6% 9% 12% 42%	3849
	21st to end	Day	11% 7% 3 7% 6% 7% 7% 5% 7% 8% 32%	4312
September	1st to 10th	Day	10% 4 2 7% 6% 6% 7% 5% 7% 10% 36%	2400
	11th to 20th	Day	14% 6% 2 7% 6% 5% 5% 5% 7% 7% 36%	2286
	21st to end	Day	10% 5% 2 6% 6% 5% 5% 3 5% 8% 44%	2133
October	1st to 10th	Day	6% 4 2 5% 4 4 4 3 4 6% 58%	2000
	11th to 20th	Day	9% 5% 1 5% 4 4 3 3 6% 7% 54%	1980
	21st to end	Day	11% 5% 2 4 3 3 4 4 5% 6% 53%	2090
November	1st to 10th	Day	12% 6% 2 5% 5% 4 5% 4 5% 6% 46%	1958
	11th to 20th	Day	10% 7% 3 5% 3 3 4 3 4 6% 52%	2000
	21st to end	Day	15% 7% 2 6% 3 3 5% 4 4 6% 46%	2000
December	1st to 10th	Day	19% 8% 3 7% 4 3 3 3 3 6% 40%	3173
	11th to 20th	Day	13% 7% 3 8% 5% 4 4 4 4 5% 43%	3391
	21st to end	Day	16% 7% 3 6% 3 3 3 3 5% 6% 45%	4488
January	1st to 10th	Night	18% 6% 4 5% 3 3 3 3 5% 5% 46%	5888
	11th to 20th	Night	17% 7% 2 5% 4 3 3 2 3 5% 47%	5900
	21st to end	Night	26% 10% 3 7% 4 3 3 2 4 6% 31%	6490
February	1st to 10th	Night	17% 9% 3 7% 4 4 4 3 3 5% 40%	2589
	11th to 20th	Night	20% 9% 3 6% 3 3 3 3 4 5% 41%	2285
	21st to end	Night	21% 10% 3 7% 4 3 3 2 5% 6% 37%	1815
March	1st to 10th	Night	20% 10% 3 7% 3 3 3 3 4 5% 38%	4919
	11th to 20th	Night	20% 8% 2 6% 4 3 3 3 4 5% 42%	4980
	21st to end	Night	19% 7% 3 6% 4 3 4 3 5% 5% 42%	5467
April	1st to 10th	Night	15% 6% 3 6% 4 4 4 3 6% 8% 40%	2087
	11th to 20th	Night	14% 6% 1 5% 3 3 4 3 5% 7% 48%	1975
	21st to end	Night	9% 5% 2 6% 4 5% 5% 3 5% 8% 48%	2000
May	1st to 10th	Night	21% 9% 3 7% 5% 4 5% 3 6% 9% 28%	4490
	11th to 20th	Night	14% 6% 3 6% 4 4 4 4 6% 8% 42%	4489
	21st to end	Night	11% 7% 2 7% 5% 5% 5% 5% 8% 9% 35%	4450
June	1st to 10th	Night	5% 3 2 5% 4 4 4 4 7% 12% 51%	1800
	11th to 20th	Night	4 4 2 5% 5% 4 4 4 7% 13% 50%	1800
	21st to end	Night	5% 5% 2 5% 4 5% 6% 5% 9% 13% 42%	1800
July	1st to 10th	Night	3 4 2 7% 4 5% 6% 5% 9% 14% 39%	4078
	11th to 20th	Night	3 4 2 6% 5% 5% 6% 5% 8% 11% 45%	4077
	21st to end	Night	5% 6% 3 7% 5% 5% 5% 4 7% 10% 42%	4449
August	1st to 10th	Night	2 2 1 2 2 3 4 4 7% 11% 63%	3053
	11th to 20th	Night	2 2 1 3 3 3 4 4 6% 13% 60%	3200
	21st to end	Night	7% 5% 2 6% 5% 6% 6% 6% 7% 9% 41%	3586
September	1st to 10th	Night	8% 5% 2 6% 4 4 5% 4 7% 12% 45%	2000
	11th to 20th	Night	10% 6% 2 6% 5% 6% 4 3 6% 9% 41%	2108
	21st to end	Night	8% 4 2 5% 3 3 4 3 5% 7% 56%	2245
October	1st to 10th	Night	5% 4 2 4 3 3 4 4 5% 8% 58%	2400
	11th to 20th	Night	8% 4 2 4 3 4 3 3 4 6% 59%	2377
	21st to end	Night	10% 5% 2 4 2 2 3 3 5% 5% 58%	2508
November	1st to 10th	Night	10% 5% 2 5% 4 4 4 3 6% 6% 52%	2340
	11th to 20th	Night	11% 6% 2 5% 3 3 3 2 5% 6% 56%	2400
	21st to end	Night	14% 8% 2 7% 4 3 3 3 4 6% 46%	2400
December	1st to 10th	Night	21% 8% 3 7% 5% 4 4 2 5% 6% 36%	4005
	11th to 20th	Night	12% 9% 3 7% 4 4 4 3 4 6% 43%	4816
	21st to end	Night	16% 9% 3 6% 3 3 3 3 4 5% 46%	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	47% 3 4 21% 19% 7%	4078
	11th to 20th	Day	37% 2 5% 16% 27% 12%	4080
	21st to end	Day	55% 2 4 14% 15% 11%	4488
February	1st to 10th	Day	48% 3 7% 15% 17% 9%	1809
	11th to 20th	Day	50% 2 7% 15% 16% 9%	2027
	21st to end	Day	52% 3 7% 15% 16% 8%	1815
March	1st to 10th	Day	52% 3 8% 12% 15% 10%	4936
	11th to 20th	Day	43% 2 9% 12% 19% 15%	4980
	21st to end	Day	46% 3 9% 19% 19% 4	5464
April	1st to 10th	Day	42% 4 10% 19% 16% 9%	2310
	11th to 20th	Day	42% 3 11% 18% 17% 9%	2374
	21st to end	Day	36% 4 13% 21% 22% 5%	2400
May	1st to 10th	Day	51% 4 12% 21% 10% 2	5440
	11th to 20th	Day	36% 5% 15% 23% 19% 2	5408
	21st to end	Day	39% 6% 16% 27% 11% 1	6435
June	1st to 10th	Day	39% 6% 17% 23% 15% 1	2600
	11th to 20th	Day	38% 7% 15% 25% 13% 2	2600
	21st to end	Day	42% 9% 21% 21% 7%	2600
July	1st to 10th	Day	41% 12% 27% 18% 2	5836
	11th to 20th	Day	44% 12% 27% 15% 2	5831
	21st to end	Day	45% 9% 19% 24% 3 1	6240
August	1st to 10th	Day	23% 6% 16% 35% 20%	4072
	11th to 20th	Day	28% 10% 29% 29% 3	3885
	21st to end	Day	48% 8% 14% 15% 14% 2	4311
September	1st to 10th	Day	42% 8% 15% 19% 13% 4	2400
	11th to 20th	Day	45% 6% 13% 19% 13% 5%	2286
	21st to end	Day	38% 4 11% 22% 15% 10%	2133
October	1st to 10th	Day	24% 4 5% 13% 20% 34%	3260
	11th to 20th	Day	20% 2 5% 21% 31% 21%	3220
	21st to end	Day	25% 3 5% 10% 43% 14%	3428
November	1st to 10th	Day	36% 4 9% 18% 22% 10%	1958
	11th to 20th	Day	33% 3 6% 18% 27% 13%	2000
	21st to end	Day	40% 4 8% 19% 21% 9%	2000
December	1st to 10th	Day	47% 3 7% 17% 21% 6%	3173
	11th to 20th	Day	42% 4 7% 15% 20% 12%	3389
	21st to end	Day	41% 3 6% 18% 24% 9%	4488
January	1st to 10th	Night	42% 2 4 21% 23% 7%	5888
	11th to 20th	Night	41% 2 4 17% 26% 10%	5900
	21st to end	Night	55% 2 4 13% 15% 11%	6490
February	1st to 10th	Night	47% 2 6% 14% 19% 11%	2589
	11th to 20th	Night	46% 3 6% 18% 18% 10%	2286
	21st to end	Night	49% 3 8% 14% 15% 11%	1815
March	1st to 10th	Night	49% 2 7% 14% 16% 12%	4919
	11th to 20th	Night	46% 2 8% 14% 15% 16%	4980
	21st to end	Night	45% 3 9% 18% 20% 7%	5467
April	1st to 10th	Night	42% 4 10% 19% 16% 10%	2087
	11th to 20th	Night	36% 3 13% 21% 16% 12%	1975
	21st to end	Night	35% 4 11% 23% 21% 6%	2000
May	1st to 10th	Night	53% 4 11% 18% 10% 3	4520
	11th to 20th	Night	39% 4 13% 22% 20% 2	4490
	21st to end	Night	40% 6% 20% 25% 9% 1	4459
June	1st to 10th	Night	26% 5% 22% 30% 15% 1	1800
	11th to 20th	Night	25% 8% 20% 30% 14% 2	1800
	21st to end	Night	31% 8% 27% 24% 9%	1800
July	1st to 10th	Night	32% 10% 36% 19% 3	4035
	11th to 20th	Night	29% 11% 38% 19% 2	4026
	21st to end	Night	37% 11% 20% 27% 6%	4320
August	1st to 10th	Night	14% 6% 20% 40% 19%	3043
	11th to 20th	Night	17% 7% 38% 33% 6%	3230
	21st to end	Night	38% 10% 17% 20% 14% 2	3586
September	1st to 10th	Night	32% 8% 22% 21% 13% 4	2000
	11th to 20th	Night	38% 6% 18% 19% 14% 5%	2108
	21st to end	Night	28% 5% 13% 25% 18% 11%	2245
October	1st to 10th	Night	20% 3 8% 15% 19% 35%	3920
	11th to 20th	Night	17% 3 4 22% 31% 22%	3876
	21st to end	Night	20% 2 6% 13% 39% 20%	4120
November	1st to 10th	Night	32% 3 9% 21% 23% 11%	2340
	11th to 20th	Night	31% 2 7% 20% 26% 14%	2400
	21st to end	Night	40% 2 6% 20% 21% 11%	2400
December	1st to 10th	Night	51% 3 5% 16% 18% 6%	4005
	11th to 20th	Night	40% 4 9% 14% 21% 12%	4817
	21st to end	Night	43% 3 5% 16% 25% 9%	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	28% 11% 39% 15% 7% 1	300
	11th to 20th	Day	18% 16% 35% 22% 9% 1	300
	21st to end	Day	24% 14% 37% 21% 4	330
February	1st to 10th	Day	19% 17% 34% 23% 6%	300
	11th to 20th	Day	29% 17% 30% 21% 3	300
	21st to end	Day	23% 19% 39% 14% 4 1	249
March	1st to 10th	Day	27% 15% 33% 18% 7%	300
	11th to 20th	Day	16% 21% 41% 16% 5% 1	300
	21st to end	Day	16% 19% 36% 20% 7% 1	330
April	1st to 10th	Day	16% 14% 32% 28% 10%	410
	11th to 20th	Day	21% 11% 29% 25% 13% 1	492
	21st to end	Day	13% 8% 33% 28% 16% 2	500
May	1st to 10th	Day	15% 10% 26% 32% 14% 3	503
	11th to 20th	Day	12% 6% 21% 34% 22% 5%	527
	21st to end	Day	6% 4 26% 35% 22% 7%	777
June	1st to 10th	Day	7% 2 15% 35% 28% 13%	730
	11th to 20th	Day	6% 2 14% 35% 31% 12%	730
	21st to end	Day	10% 2 9% 26% 33% 20%	730
July	1st to 10th	Day	7% 3 6% 27% 37% 20%	721
	11th to 20th	Day	6% 2 5% 24% 36% 25%	718
	21st to end	Day	8% 2 5% 25% 38% 23%	794
August	1st to 10th	Day	4 2 2 18% 43% 31%	643
	11th to 20th	Day	4 2 3 11% 44% 36%	519
	21st to end	Day	12% 2 6% 18% 36% 27%	583
September	1st to 10th	Day	9% 2 6% 21% 39% 22%	530
	11th to 20th	Day	13% 2 5% 25% 38% 18%	416
	21st to end	Day	10% 1 14% 28% 37% 11%	330
October	1st to 10th	Day	8% 2 17% 38% 27% 8%	330
	11th to 20th	Day	9% 3 16% 39% 19% 13%	324
	21st to end	Day	15% 9% 21% 33% 16% 7%	330
November	1st to 10th	Day	14% 7% 25% 27% 22% 5%	300
	11th to 20th	Day	14% 8% 30% 33% 13% 2	300
	21st to end	Day	18% 14% 30% 24% 12% 2	300
December	1st to 10th	Day	20% 7% 35% 23% 12% 3	300
	11th to 20th	Day	16% 12% 39% 25% 6% 1	300
	21st to end	Day	20% 11% 39% 21% 7% 2	330
January	1st to 10th	Night	22% 7% 33% 30% 8%	1000
	11th to 20th	Night	22% 8% 31% 32% 8% 1	1000
	21st to end	Night	22% 8% 33% 31% 7%	1100
February	1st to 10th	Night	22% 9% 31% 32% 5%	989
	11th to 20th	Night	24% 10% 30% 30% 6%	730
	21st to end	Night	23% 11% 33% 28% 4	495
March	1st to 10th	Night	20% 7% 30% 34% 9%	600
	11th to 20th	Night	19% 7% 32% 33% 10%	600
	21st to end	Night	18% 5% 29% 35% 11%	660
April	1st to 10th	Night	19% 7% 30% 34% 10% 1	600
	11th to 20th	Night	16% 9% 28% 32% 15%	593
	21st to end	Night	11% 4 31% 39% 15% 1	600
May	1st to 10th	Night	17% 5% 22% 42% 14% 1	600
	11th to 20th	Night	10% 3 25% 38% 22% 1	591
	21st to end	Night	7% 3 14% 38% 34% 4	650
June	1st to 10th	Night	5% 1 7% 33% 47% 8%	600
	11th to 20th	Night	5% 1 5% 34% 48% 7%	600
	21st to end	Night	8% 1 5% 22% 50% 15%	600
July	1st to 10th	Night	5% 2 2 18% 54% 19%	585
	11th to 20th	Night	5% 2 2 13% 55% 23%	582
	21st to end	Night	5% 1 2 19% 54% 19%	657
August	1st to 10th	Night	4 1 2 12% 61% 20%	597
	11th to 20th	Night	5% 1 1 13% 58% 22%	594
	21st to end	Night	9% 2 4 18% 49% 19%	660
September	1st to 10th	Night	9% 2 4 21% 49% 16%	600
	11th to 20th	Night	12% 2 5% 23% 50% 10%	600
	21st to end	Night	9% 1 7% 32% 45% 7%	645
October	1st to 10th	Night	7% 2 9% 39% 38% 6%	800
	11th to 20th	Night	9% 2 17% 40% 27% 4	793
	21st to end	Night	12% 5% 17% 39% 24% 3	836
November	1st to 10th	Night	11% 3 19% 42% 23% 2	780
	11th to 20th	Night	14% 6% 22% 40% 18% 1	800
	21st to end	Night	16% 6% 27% 34% 15% 1	800
December	1st to 10th	Night	20% 7% 25% 33% 15%	846
	11th to 20th	Night	20% 7% 29% 34% 9% 1	1000
	21st to end	Night	22% 8% 29% 33% 9%	1100

Page generated at 2025-10-16 00:50:28. Version ac07

Copyright © 2025 Attilla Danko.