Lamoine Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lamoine Observatory clear sky chart from 2005-11-06 to 2024-11-28.

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	19% 8% 2 6% 4 4 4 3 5% 7% 37%	101449
	Night	20% 9% 3 6% 4 4 4 3 5% 6% 35%	98107
Transparency	Day	46% 6% 12% 22% 13% 1	104989
	Night	48% 6% 12% 21% 12% 1	102658
Seeing	Day	23% 15% 32% 21% 7% 1	15947
	Night	25% 15% 29% 23% 7% 1	24225

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	18% 9% 3 6% 5% 4 4 3 4 6% 40%	2513
	11th to 20th	Day	18% 8% 2 5% 3 3 5% 3 4 5% 45%	2520
	21st to end	Day	17% 10% 3 7% 4 4 3 3 5% 7% 36%	2879
February	1st to 10th	Day	17% 12% 3 7% 4 4 4 4 6% 7% 32%	1710
	11th to 20th	Day	14% 9% 3 7% 5% 5% 5% 4 6% 6% 37%	1747
	21st to end	Day	14% 11% 3 8% 5% 4 5% 4 5% 6% 36%	1570
March	1st to 10th	Day	26% 12% 3 6% 4 3 3 3 4 6% 30%	3171
	11th to 20th	Day	19% 8% 3 7% 5% 4 5% 3 5% 6% 34%	3480
	21st to end	Day	28% 9% 3 6% 4 4 4 3 5% 5% 29%	3816
April	1st to 10th	Day	20% 11% 3 6% 4 4 4 3 5% 6% 34%	2229
	11th to 20th	Day	19% 8% 3 6% 4 3 3 3 4 7% 39%	2435
	21st to end	Day	21% 9% 2 5% 4 4 4 3 4 7% 36%	2470
May	1st to 10th	Day	19% 10% 2 6% 5% 4 4 3 6% 7% 33%	4106
	11th to 20th	Day	18% 8% 2 7% 4 4 4 4 6% 7% 36%	4081
	21st to end	Day	18% 8% 3 6% 4 4 5% 4 6% 8% 34%	4934
June	1st to 10th	Day	22% 9% 3 6% 4 4 4 4 5% 8% 31%	2850
	11th to 20th	Day	18% 8% 3 5% 4 4 4 3 4 8% 38%	2850
	21st to end	Day	25% 8% 2 6% 4 4 4 4 5% 7% 30%	2850
July	1st to 10th	Day	18% 8% 2 6% 4 5% 5% 3 6% 7% 36%	4617
	11th to 20th	Day	17% 7% 2 5% 3 3 4 3 6% 9% 41%	4440
	21st to end	Day	21% 8% 2 5% 4 4 4 3 6% 8% 37%	4689
August	1st to 10th	Day	19% 8% 3 7% 4 4 4 3 5% 8% 35%	4105
	11th to 20th	Day	18% 8% 2 7% 4 5% 4 3 6% 7% 35%	4045
	21st to end	Day	10% 5% 2 5% 4 3 3 4 6% 9% 50%	4532
September	1st to 10th	Day	12% 5% 2 4 3 4 4 3 4 8% 49%	2185
	11th to 20th	Day	13% 5% 2 4 3 4 4 2 4 6% 52%	2090
	21st to end	Day	18% 6% 2 5% 3 4 3 4 4 6% 43%	2090
October	1st to 10th	Day	17% 7% 3 6% 3 4 5% 4 5% 6% 41%	2020
	11th to 20th	Day	19% 6% 2 6% 4 4 3 3 4 6% 43%	1900
	21st to end	Day	22% 7% 3 4 4 4 4 3 4 5% 39%	1895
November	1st to 10th	Day	18% 7% 2 7% 4 3 4 3 5% 6% 42%	1761
	11th to 20th	Day	21% 5% 2 5% 2 3 4 4 5% 7% 42%	1735
	21st to end	Day	20% 10% 3 6% 3 3 3 3 5% 5% 40%	1576
December	1st to 10th	Day	23% 10% 2 6% 4 5% 5% 3 5% 5% 33%	1459
	11th to 20th	Day	24% 10% 2 6% 4 4 3 4 5% 6% 33%	1668
	21st to end	Day	26% 9% 2 6% 3 3 3 3 4 6% 35%	2431
January	1st to 10th	Night	15% 9% 3 7% 5% 4 4 3 5% 7% 40%	4429
	11th to 20th	Night	14% 10% 3 9% 5% 4 4 3 5% 6% 37%	4440
	21st to end	Night	17% 11% 4 8% 5% 4 4 4 5% 7% 33%	4774
February	1st to 10th	Night	18% 10% 3 7% 4 4 5% 3 5% 6% 34%	2470
	11th to 20th	Night	15% 9% 3 7% 5% 4 4 3 5% 6% 38%	2318
	21st to end	Night	15% 10% 3 6% 5% 4 4 3 5% 6% 38%	1884
March	1st to 10th	Night	28% 13% 3 5% 4 3 3 2 3 4 31%	3667
	11th to 20th	Night	15% 11% 3 7% 6% 6% 5% 4 7% 6% 29%	3479
	21st to end	Night	29% 9% 3 6% 4 4 4 4 5% 5% 28%	3816
April	1st to 10th	Night	23% 11% 2 5% 4 4 4 4 4 5% 34%	1948
	11th to 20th	Night	21% 8% 3 7% 4 4 3 3 5% 7% 35%	1693
	21st to end	Night	24% 9% 3 6% 4 3 3 3 4 6% 34%	1710
May	1st to 10th	Night	24% 8% 2 6% 4 3 4 3 5% 8% 33%	2834
	11th to 20th	Night	18% 7% 3 7% 6% 5% 5% 5% 6% 8% 30%	2813
	21st to end	Night	15% 11% 4 8% 5% 5% 5% 3 5% 6% 34%	2672
June	1st to 10th	Night	25% 10% 3 6% 4 4 4 4 6% 7% 28%	1330
	11th to 20th	Night	20% 9% 2 6% 3 3 4 3 6% 7% 36%	1330
	21st to end	Night	27% 11% 2 5% 4 5% 4 3 5% 6% 28%	1330
July	1st to 10th	Night	19% 10% 3 7% 5% 4 5% 5% 7% 8% 27%	2331
	11th to 20th	Night	20% 8% 2 6% 4 4 5% 4 6% 8% 34%	2520
	21st to end	Night	18% 8% 2 7% 4 4 4 4 6% 8% 34%	2833
August	1st to 10th	Night	24% 10% 3 7% 4 4 4 4 5% 6% 28%	2825
	11th to 20th	Night	19% 9% 3 7% 4 4 6% 5% 6% 8% 30%	2782
	21st to end	Night	10% 6% 2 6% 4 4 4 3 6% 9% 45%	3124
September	1st to 10th	Night	14% 5% 2 4 4 3 4 3 6% 7% 48%	1992
	11th to 20th	Night	16% 6% 2 5% 3 2 3 3 4 7% 49%	2090
	21st to end	Night	18% 7% 2 5% 3 2 4 3 5% 8% 44%	2090
October	1st to 10th	Night	20% 6% 2 5% 4 4 4 4 5% 7% 41%	2159
	11th to 20th	Night	19% 6% 2 6% 4 4 4 3 4 7% 43%	2280
	21st to end	Night	23% 9% 2 5% 4 3 3 3 4 6% 38%	2699
November	1st to 10th	Night	18% 7% 2 5% 4 3 5% 3 5% 6% 42%	2537
	11th to 20th	Night	18% 7% 2 5% 4 4 5% 3 5% 6% 41%	2663
	21st to end	Night	18% 9% 3 5% 3 4 4 4 5% 6% 38%	2759
December	1st to 10th	Night	24% 9% 2 6% 4 4 4 3 5% 6% 32%	2719
	11th to 20th	Night	24% 9% 2 5% 3 3 2 3 4 7% 37%	3531
	21st to end	Night	25% 9% 3 5% 3 3 3 3 5% 6% 36%	5236

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% 5% 15% 24% 8% 1	2514
	11th to 20th	Day	44% 6% 12% 25% 12% 2	2520
	21st to end	Day	48% 5% 15% 20% 12%	2879
February	1st to 10th	Day	53% 5% 13% 17% 11% 2	1710
	11th to 20th	Day	48% 5% 13% 19% 13% 1	1755
	21st to end	Day	48% 5% 11% 21% 10% 4	1570
March	1st to 10th	Day	56% 5% 10% 14% 13% 3	3175
	11th to 20th	Day	46% 6% 14% 19% 12% 2	3480
	21st to end	Day	57% 3 7% 14% 15% 4	3816
April	1st to 10th	Day	50% 5% 10% 17% 15% 3	2229
	11th to 20th	Day	44% 5% 11% 23% 14% 3	2435
	21st to end	Day	47% 5% 9% 18% 17% 3	2470
May	1st to 10th	Day	48% 9% 14% 20% 8% 1	4120
	11th to 20th	Day	45% 7% 16% 23% 9% 1	4085
	21st to end	Day	46% 8% 13% 19% 13% 1	4934
June	1st to 10th	Day	51% 7% 12% 20% 9%	2850
	11th to 20th	Day	45% 6% 12% 20% 15% 2	2850
	21st to end	Day	54% 7% 10% 16% 10% 2	2850
July	1st to 10th	Day	48% 7% 10% 23% 11%	4546
	11th to 20th	Day	41% 7% 16% 25% 11%	4365
	21st to end	Day	45% 7% 12% 21% 13% 1	4540
August	1st to 10th	Day	48% 7% 13% 24% 7%	4092
	11th to 20th	Day	47% 7% 17% 20% 9%	4084
	21st to end	Day	30% 7% 13% 29% 21% 1	4532
September	1st to 10th	Day	34% 7% 13% 27% 18% 2	2185
	11th to 20th	Day	34% 6% 12% 26% 20% 3	2090
	21st to end	Day	42% 6% 9% 26% 16% 1	2090
October	1st to 10th	Day	46% 7% 12% 23% 12% 1	3358
	11th to 20th	Day	32% 3 9% 34% 21%	3140
	21st to end	Day	33% 5% 17% 24% 18% 3	3095
November	1st to 10th	Day	43% 5% 13% 24% 13% 1	1761
	11th to 20th	Day	42% 6% 9% 22% 18% 3	1735
	21st to end	Day	48% 5% 16% 22% 8% 1	1576
December	1st to 10th	Day	53% 6% 12% 20% 8% 1	1459
	11th to 20th	Day	54% 4 10% 21% 10% 1	1668
	21st to end	Day	52% 6% 12% 18% 8% 3	2431
January	1st to 10th	Night	46% 5% 15% 26% 8% 1	4429
	11th to 20th	Night	49% 6% 13% 21% 10% 1	4440
	21st to end	Night	52% 5% 12% 22% 9% 1	4774
February	1st to 10th	Night	52% 5% 12% 18% 11% 2	2470
	11th to 20th	Night	47% 6% 11% 20% 15% 2	2321
	21st to end	Night	48% 4 10% 21% 14% 4	1884
March	1st to 10th	Night	59% 3 9% 14% 12% 3	3676
	11th to 20th	Night	48% 9% 17% 14% 11% 1	3480
	21st to end	Night	58% 3 7% 15% 14% 2	3816
April	1st to 10th	Night	52% 5% 10% 14% 16% 3	1948
	11th to 20th	Night	49% 5% 8% 21% 15% 2	1693
	21st to end	Night	52% 5% 9% 17% 14% 3	1710
May	1st to 10th	Night	49% 7% 16% 19% 8% 1	2840
	11th to 20th	Night	49% 9% 16% 18% 6% 1	2814
	21st to end	Night	49% 7% 14% 20% 10% 1	2673
June	1st to 10th	Night	55% 7% 10% 19% 7% 1	1330
	11th to 20th	Night	47% 8% 12% 21% 11% 2	1330
	21st to end	Night	57% 5% 8% 18% 9% 2	1330
July	1st to 10th	Night	54% 8% 11% 17% 10% 1	2293
	11th to 20th	Night	47% 8% 14% 22% 10%	2472
	21st to end	Night	48% 7% 12% 20% 12% 1	2742
August	1st to 10th	Night	57% 7% 11% 19% 7%	2813
	11th to 20th	Night	50% 7% 13% 21% 9%	2809
	21st to end	Night	36% 7% 11% 25% 21% 1	3124
September	1st to 10th	Night	36% 6% 12% 28% 17% 1	1992
	11th to 20th	Night	37% 5% 11% 26% 19% 2	2090
	21st to end	Night	40% 4 10% 28% 17% 1	2090
October	1st to 10th	Night	42% 4 13% 25% 15% 1	3601
	11th to 20th	Night	34% 4 10% 29% 24% 1	3779
	21st to end	Night	39% 3 10% 30% 15% 3	4449
November	1st to 10th	Night	43% 5% 13% 25% 14% 1	2537
	11th to 20th	Night	44% 5% 11% 22% 16% 2	2663
	21st to end	Night	46% 6% 14% 20% 12% 2	2759
December	1st to 10th	Night	55% 5% 11% 19% 10%	2719
	11th to 20th	Night	49% 5% 12% 21% 13% 1	3532
	21st to end	Night	51% 6% 13% 17% 11% 2	5236

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	26% 28% 29% 13% 3	180
	11th to 20th	Day	31% 25% 32% 11% 2 1	180
	21st to end	Day	19% 25% 35% 17% 3	266
February	1st to 10th	Day	26% 26% 31% 15% 2	370
	11th to 20th	Day	26% 31% 33% 9% 2	406
	21st to end	Day	24% 24% 34% 16% 2	382
March	1st to 10th	Day	27% 25% 33% 14% 2	460
	11th to 20th	Day	23% 25% 33% 16% 3	460
	21st to end	Day	28% 24% 28% 15% 5% 1	506
April	1st to 10th	Day	29% 23% 32% 12% 3 1	460
	11th to 20th	Day	27% 18% 37% 13% 5% 1	452
	21st to end	Day	25% 17% 36% 17% 4 1	460
May	1st to 10th	Day	26% 21% 34% 15% 4 1	463
	11th to 20th	Day	17% 18% 36% 23% 5%	487
	21st to end	Day	25% 12% 36% 18% 8% 1	644
June	1st to 10th	Day	25% 9% 32% 24% 8% 1	680
	11th to 20th	Day	24% 8% 30% 24% 12% 1	680
	21st to end	Day	30% 6% 29% 25% 9% 1	680
July	1st to 10th	Day	23% 7% 33% 23% 13% 1	596
	11th to 20th	Day	20% 4 33% 31% 11% 1	484
	21st to end	Day	17% 6% 35% 31% 10% 2	532
August	1st to 10th	Day	16% 7% 30% 34% 12% 1	486
	11th to 20th	Day	20% 6% 30% 29% 12% 3	479
	21st to end	Day	17% 7% 29% 32% 12% 3	539
September	1st to 10th	Day	18% 5% 34% 32% 10% 1	490
	11th to 20th	Day	20% 10% 29% 24% 11% 6%	490
	21st to end	Day	19% 9% 33% 25% 11% 4	490
October	1st to 10th	Day	18% 14% 26% 28% 12% 1	453
	11th to 20th	Day	19% 17% 31% 23% 8% 2	390
	21st to end	Day	29% 14% 33% 19% 5%	429
November	1st to 10th	Day	22% 21% 29% 21% 6% 1	395
	11th to 20th	Day	24% 23% 33% 16% 3 1	400
	21st to end	Day	29% 24% 28% 16% 4	391
December	1st to 10th	Day	28% 20% 33% 16% 3	309
	11th to 20th	Day	34% 28% 28% 8% 1	180
	21st to end	Day	32% 29% 21% 14% 4	198
January	1st to 10th	Night	23% 25% 31% 18% 2	760
	11th to 20th	Night	28% 24% 32% 14% 3	760
	21st to end	Night	19% 29% 33% 16% 3	836
February	1st to 10th	Night	25% 25% 34% 13% 3	760
	11th to 20th	Night	23% 30% 31% 13% 2 1	743
	21st to end	Night	23% 21% 33% 19% 4	628
March	1st to 10th	Night	25% 20% 35% 18% 2	760
	11th to 20th	Night	23% 20% 32% 20% 6%	760
	21st to end	Night	25% 18% 33% 18% 6% 1	836
April	1st to 10th	Night	31% 15% 32% 19% 3	760
	11th to 20th	Night	26% 10% 34% 25% 4	569
	21st to end	Night	30% 10% 29% 22% 7% 1	570
May	1st to 10th	Night	27% 8% 31% 26% 7% 1	570
	11th to 20th	Night	24% 8% 33% 27% 7%	562
	21st to end	Night	25% 6% 27% 31% 10% 1	495
June	1st to 10th	Night	32% 5% 24% 29% 8% 1	380
	11th to 20th	Night	25% 4 26% 32% 12% 1	380
	21st to end	Night	35% 2 19% 34% 10% 1	380
July	1st to 10th	Night	25% 3 25% 35% 12%	370
	11th to 20th	Night	24% 2 22% 37% 14% 1	368
	21st to end	Night	25% 2 21% 39% 13% 1	473
August	1st to 10th	Night	23% 3 21% 38% 14% 1	568
	11th to 20th	Night	22% 2 21% 39% 14% 1	562
	21st to end	Night	18% 4 22% 35% 19% 2	627
September	1st to 10th	Night	17% 3 28% 35% 15% 1	738
	11th to 20th	Night	20% 6% 25% 28% 16% 4	760
	21st to end	Night	21% 6% 28% 29% 14% 2	760
October	1st to 10th	Night	23% 9% 25% 26% 15% 1	760
	11th to 20th	Night	21% 14% 28% 23% 11% 1	760
	21st to end	Night	28% 17% 29% 20% 5%	836
November	1st to 10th	Night	22% 16% 30% 23% 7% 1	780
	11th to 20th	Night	22% 24% 29% 19% 6% 1	833
	21st to end	Night	26% 22% 30% 16% 5%	886
December	1st to 10th	Night	31% 19% 33% 14% 3	850
	11th to 20th	Night	28% 26% 29% 15% 2	850
	21st to end	Night	30% 22% 30% 15% 3	935

Page generated at 2024-11-25 00:22:21. Version ac07

Copyright © 2024 Attilla Danko.