Milledgeville
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Milledgeville 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	12% 6% 2 6% 4 4 5% 4 6% 8% 43%	109400
	Night	13% 6% 2 6% 4 4 4 4 6% 8% 45%	109952
Transparency	Day	37% 6% 11% 20% 19% 7%	113194
	Night	36% 5% 10% 19% 21% 8%	114297
Seeing	Day	15% 9% 23% 24% 20% 9%	15520
	Night	15% 8% 22% 30% 21% 3	25659

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	15% 4 2 4 3 3 3 2 4 5% 54%	4056
	11th to 20th	Day	12% 6% 2 4 3 2 2 2 5% 7% 55%	4060
	21st to end	Day	18% 7% 2 6% 4 4 4 2 4 6% 43%	4534
February	1st to 10th	Day	15% 7% 2 7% 4 4 4 4 5% 7% 41%	2000
	11th to 20th	Day	20% 6% 2 5% 3 3 4 3 5% 6% 43%	1948
	21st to end	Day	16% 7% 2 6% 4 3 5% 3 5% 7% 42%	1650
March	1st to 10th	Day	23% 9% 2 7% 3 3 3 3 5% 6% 36%	3441
	11th to 20th	Day	10% 5% 2 5% 4 4 4 4 6% 7% 51%	3590
	21st to end	Day	18% 6% 2 6% 5% 4 4 3 4 6% 43%	3881
April	1st to 10th	Day	12% 4 2 6% 4 4 5% 4 4 6% 49%	2090
	11th to 20th	Day	11% 6% 2 5% 4 4 5% 3 5% 7% 48%	2190
	21st to end	Day	7% 4 2 5% 5% 4 4 4 5% 7% 53%	2470
May	1st to 10th	Day	8% 6% 2 7% 5% 4 5% 4 5% 7% 46%	4082
	11th to 20th	Day	17% 7% 2 7% 5% 5% 5% 4 6% 7% 37%	4081
	21st to end	Day	7% 3 1 6% 4 5% 5% 5% 7% 10% 48%	4476
June	1st to 10th	Day	10% 6% 2 6% 6% 6% 7% 5% 8% 9% 34%	2470
	11th to 20th	Day	5% 4 2 5% 5% 5% 6% 4 7% 12% 43%	2470
	21st to end	Day	5% 5% 2 7% 7% 6% 7% 6% 8% 11% 36%	2470
July	1st to 10th	Day	13% 6% 2 7% 6% 7% 7% 7% 9% 11% 24%	4120
	11th to 20th	Day	5% 5% 3 7% 6% 7% 8% 6% 10% 11% 34%	4120
	21st to end	Day	8% 7% 3 9% 7% 8% 9% 6% 10% 12% 20%	4466
August	1st to 10th	Day	13% 5% 2 7% 5% 5% 6% 6% 9% 12% 30%	4104
	11th to 20th	Day	7% 4 1 5% 4 4 6% 5% 8% 10% 45%	3919
	21st to end	Day	7% 4 2 5% 5% 5% 5% 4 6% 10% 47%	4062
September	1st to 10th	Day	9% 5% 3 7% 6% 6% 5% 5% 8% 9% 37%	2090
	11th to 20th	Day	12% 7% 2 7% 5% 4 4 4 7% 8% 39%	2090
	21st to end	Day	14% 7% 2 6% 4 4 3 4 6% 7% 43%	2090
October	1st to 10th	Day	13% 5% 2 4 4 3 4 3 4 7% 51%	2090
	11th to 20th	Day	13% 3 1 3 3 3 4 3 5% 6% 57%	1933
	21st to end	Day	11% 4 2 4 3 4 4 3 5% 5% 56%	2090
November	1st to 10th	Day	12% 6% 2 5% 4 4 3 3 4 5% 52%	1898
	11th to 20th	Day	14% 5% 2 3 4 2 3 2 5% 6% 53%	1800
	21st to end	Day	14% 5% 2 5% 4 4 4 3 5% 7% 47%	1800
December	1st to 10th	Day	12% 6% 2 6% 5% 3 4 3 5% 6% 49%	2930
	11th to 20th	Day	16% 6% 2 5% 3 3 4 3 5% 6% 48%	3373
	21st to end	Day	22% 7% 2 4 3 3 4 2 4 5% 44%	4466
January	1st to 10th	Night	14% 5% 2 4 3 3 3 3 5% 6% 53%	5889
	11th to 20th	Night	12% 6% 2 5% 4 4 4 3 6% 6% 48%	5900
	21st to end	Night	16% 8% 3 6% 3 3 3 3 5% 6% 43%	6419
February	1st to 10th	Night	15% 6% 2 5% 5% 3 4 3 5% 7% 45%	2400
	11th to 20th	Night	19% 6% 2 5% 4 3 3 3 5% 5% 44%	2338
	21st to end	Night	13% 6% 3 7% 4 4 4 3 5% 6% 45%	1980
March	1st to 10th	Night	22% 9% 2 6% 3 3 3 3 4 6% 38%	3630
	11th to 20th	Night	12% 4 1 4 3 4 4 4 6% 8% 50%	3590
	21st to end	Night	18% 6% 2 6% 3 4 4 4 6% 6% 42%	3890
April	1st to 10th	Night	11% 5% 2 5% 4 3 3 3 6% 7% 50%	2090
	11th to 20th	Night	13% 4 2 4 3 3 4 4 6% 8% 50%	1951
	21st to end	Night	7% 4 1 6% 4 4 4 4 4 8% 54%	1710
May	1st to 10th	Night	6% 4 2 6% 4 5% 5% 6% 8% 11% 44%	2813
	11th to 20th	Night	14% 5% 2 6% 4 5% 5% 4 6% 8% 41%	2812
	21st to end	Night	7% 3 1 5% 4 4 4 4 6% 10% 52%	3079
June	1st to 10th	Night	8% 7% 2 6% 6% 7% 6% 5% 8% 11% 35%	1710
	11th to 20th	Night	5% 4 2 5% 5% 6% 6% 4 8% 11% 44%	1710
	21st to end	Night	6% 6% 1 6% 5% 5% 5% 6% 11% 12% 37%	1710
July	1st to 10th	Night	13% 7% 4 7% 6% 6% 5% 5% 8% 11% 27%	2840
	11th to 20th	Night	5% 5% 2 7% 6% 6% 7% 7% 11% 14% 29%	2840
	21st to end	Night	10% 7% 3 8% 6% 7% 7% 6% 9% 12% 24%	3087
August	1st to 10th	Night	12% 6% 3 8% 6% 6% 6% 5% 8% 12% 29%	2825
	11th to 20th	Night	8% 4 2 7% 5% 5% 6% 5% 7% 10% 42%	2904
	21st to end	Night	7% 4 2 5% 4 4 4 4 7% 10% 49%	3562
September	1st to 10th	Night	10% 6% 2 6% 5% 6% 6% 5% 7% 10% 38%	2090
	11th to 20th	Night	12% 6% 2 7% 5% 5% 4 4 6% 8% 42%	2090
	21st to end	Night	12% 4 1 7% 5% 4 5% 4 5% 7% 46%	2090
October	1st to 10th	Night	12% 5% 2 5% 4 3 3 3 4 7% 53%	2090
	11th to 20th	Night	12% 4 1 4 3 3 3 3 4 5% 59%	2247
	21st to end	Night	11% 4 1 4 3 3 4 3 4 5% 57%	2508
November	1st to 10th	Night	12% 5% 1 5% 4 4 4 2 4 5% 54%	2396
	11th to 20th	Night	15% 5% 2 4 3 3 4 2 4 5% 53%	2600
	21st to end	Night	13% 5% 2 5% 4 4 4 3 4 6% 50%	2600
December	1st to 10th	Night	13% 6% 2 5% 3 2 3 2 4 6% 55%	4250
	11th to 20th	Night	17% 5% 2 5% 3 3 3 2 4 6% 48%	4822
	21st to end	Night	20% 7% 2 6% 4 4 3 3 4 5% 42%	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	34% 3 4 19% 31% 9%	4057
	11th to 20th	Day	31% 2 3 18% 32% 13%	4060
	21st to end	Day	44% 3 4 18% 22% 10%	4534
February	1st to 10th	Day	44% 4 7% 19% 19% 8%	2000
	11th to 20th	Day	43% 3 4 19% 23% 7%	1958
	21st to end	Day	41% 4 7% 16% 23% 9%	1650
March	1st to 10th	Day	49% 4 7% 14% 18% 8%	3441
	11th to 20th	Day	32% 5% 9% 17% 24% 14%	3590
	21st to end	Day	43% 3 6% 22% 17% 8%	3881
April	1st to 10th	Day	36% 4 10% 20% 20% 10%	2090
	11th to 20th	Day	35% 4 8% 21% 21% 11%	2190
	21st to end	Day	29% 5% 11% 26% 26% 4	2470
May	1st to 10th	Day	37% 5% 12% 25% 18% 3	4120
	11th to 20th	Day	45% 5% 11% 23% 15% 1	4085
	21st to end	Day	30% 6% 16% 24% 21% 3	4489
June	1st to 10th	Day	42% 8% 16% 19% 13% 2	2470
	11th to 20th	Day	32% 9% 17% 26% 15% 1	2470
	21st to end	Day	38% 10% 19% 18% 13% 3	2470
July	1st to 10th	Day	48% 12% 19% 15% 4 2	4055
	11th to 20th	Day	38% 14% 22% 22% 4 1	4051
	21st to end	Day	50% 15% 17% 13% 4	4324
August	1st to 10th	Day	42% 10% 21% 24% 3	4091
	11th to 20th	Day	31% 9% 16% 29% 13% 1	3958
	21st to end	Day	31% 7% 16% 29% 16% 2	4062
September	1st to 10th	Day	41% 8% 14% 16% 16% 4	2090
	11th to 20th	Day	41% 8% 10% 19% 19% 3	2090
	21st to end	Day	40% 5% 10% 21% 19% 5%	2090
October	1st to 10th	Day	30% 4 5% 16% 33% 12%	3480
	11th to 20th	Day	17% 2 4 17% 27% 32%	3186
	21st to end	Day	23% 2 4 20% 35% 15%	3428
November	1st to 10th	Day	35% 4 8% 14% 26% 13%	1898
	11th to 20th	Day	33% 3 5% 21% 25% 13%	1800
	21st to end	Day	37% 3 8% 19% 25% 8%	1800
December	1st to 10th	Day	37% 4 6% 17% 26% 10%	2930
	11th to 20th	Day	39% 3 8% 21% 22% 7%	3370
	21st to end	Day	44% 3 6% 21% 23% 3	4466
January	1st to 10th	Night	33% 3 4 20% 32% 9%	5889
	11th to 20th	Night	37% 3 4 20% 27% 9%	5900
	21st to end	Night	43% 3 4 15% 27% 8%	6419
February	1st to 10th	Night	40% 4 7% 18% 22% 9%	2400
	11th to 20th	Night	43% 3 5% 17% 22% 10%	2339
	21st to end	Night	40% 4 7% 16% 19% 14%	1980
March	1st to 10th	Night	49% 3 10% 15% 14% 8%	3630
	11th to 20th	Night	31% 5% 10% 14% 27% 13%	3590
	21st to end	Night	42% 4 7% 18% 17% 12%	3890
April	1st to 10th	Night	33% 4 10% 21% 21% 11%	2090
	11th to 20th	Night	32% 4 6% 24% 22% 12%	1951
	21st to end	Night	29% 5% 11% 24% 23% 8%	1710
May	1st to 10th	Night	31% 8% 15% 25% 17% 4	2840
	11th to 20th	Night	39% 7% 13% 25% 15% 1	2813
	21st to end	Night	27% 6% 13% 28% 22% 4	3087
June	1st to 10th	Night	40% 9% 18% 19% 14% 1	1710
	11th to 20th	Night	31% 8% 18% 28% 13% 2	1710
	21st to end	Night	33% 11% 22% 19% 11% 4	1710
July	1st to 10th	Night	48% 13% 20% 13% 4 2	2795
	11th to 20th	Night	39% 13% 27% 16% 4 1	2786
	21st to end	Night	50% 16% 18% 13% 4 1	2988
August	1st to 10th	Night	45% 9% 22% 21% 3	2814
	11th to 20th	Night	34% 9% 19% 25% 12% 2	2931
	21st to end	Night	29% 8% 17% 29% 15% 2	3562
September	1st to 10th	Night	39% 9% 17% 17% 14% 4	2090
	11th to 20th	Night	39% 8% 11% 18% 18% 5%	2090
	21st to end	Night	36% 6% 11% 19% 21% 6%	2090
October	1st to 10th	Night	34% 5% 6% 13% 31% 12%	3480
	11th to 20th	Night	18% 2 4 13% 29% 34%	3733
	21st to end	Night	20% 3 4 20% 32% 20%	4120
November	1st to 10th	Night	34% 4 7% 15% 26% 14%	2396
	11th to 20th	Night	34% 3 5% 17% 26% 14%	2600
	21st to end	Night	36% 3 7% 18% 25% 10%	2600
December	1st to 10th	Night	33% 3 6% 19% 32% 7%	4250
	11th to 20th	Night	38% 4 10% 19% 22% 8%	4824
	21st to end	Night	45% 3 4 22% 23% 3	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	21% 22% 41% 13% 2	300
	11th to 20th	Day	22% 24% 33% 13% 7% 1	300
	21st to end	Day	23% 28% 35% 11% 4	330
February	1st to 10th	Day	22% 18% 39% 19% 3	300
	11th to 20th	Day	31% 22% 31% 16% 1	300
	21st to end	Day	26% 19% 39% 13% 4	249
March	1st to 10th	Day	21% 20% 29% 23% 7% 1	430
	11th to 20th	Day	18% 16% 36% 20% 9%	500
	21st to end	Day	19% 17% 35% 21% 8%	530
April	1st to 10th	Day	21% 15% 28% 23% 12% 1	460
	11th to 20th	Day	13% 14% 29% 27% 13% 3	452
	21st to end	Day	11% 11% 26% 28% 20% 5%	460
May	1st to 10th	Day	11% 12% 26% 28% 16% 8%	463
	11th to 20th	Day	15% 5% 21% 26% 22% 11%	487
	21st to end	Day	11% 6% 17% 28% 26% 12%	529
June	1st to 10th	Day	13% 3 15% 30% 27% 12%	490
	11th to 20th	Day	6% 4 16% 26% 28% 19%	490
	21st to end	Day	7% 2 13% 32% 27% 18%	490
July	1st to 10th	Day	7% 2 10% 22% 34% 24%	485
	11th to 20th	Day	8% 1 7% 20% 37% 27%	484
	21st to end	Day	5% 2 8% 27% 36% 22%	532
August	1st to 10th	Day	13% 3 12% 24% 30% 18%	486
	11th to 20th	Day	8% 1 9% 24% 37% 21%	479
	21st to end	Day	13% 2 9% 26% 32% 18%	539
September	1st to 10th	Day	10% 4 12% 28% 31% 15%	490
	11th to 20th	Day	15% 4 15% 23% 31% 12%	490
	21st to end	Day	19% 3 14% 26% 28% 9%	490
October	1st to 10th	Day	16% 4 22% 28% 22% 8%	490
	11th to 20th	Day	13% 7% 22% 30% 20% 8%	490
	21st to end	Day	15% 7% 24% 28% 20% 5%	539
November	1st to 10th	Day	19% 6% 27% 28% 17% 4	436
	11th to 20th	Day	18% 15% 37% 22% 6% 2	300
	21st to end	Day	15% 16% 29% 29% 9% 2	300
December	1st to 10th	Day	22% 18% 37% 15% 7% 1	300
	11th to 20th	Day	24% 17% 35% 18% 6% 1	300
	21st to end	Day	26% 15% 34% 19% 5% 1	330
January	1st to 10th	Night	21% 19% 33% 22% 6%	800
	11th to 20th	Night	19% 15% 30% 27% 8%	800
	21st to end	Night	20% 17% 34% 25% 3	880
February	1st to 10th	Night	21% 12% 31% 30% 7%	800
	11th to 20th	Night	24% 15% 31% 27% 3	783
	21st to end	Night	18% 15% 36% 28% 3	660
March	1st to 10th	Night	17% 15% 31% 31% 6%	800
	11th to 20th	Night	17% 14% 32% 28% 9% 1	800
	21st to end	Night	16% 14% 31% 29% 10%	863
April	1st to 10th	Night	15% 14% 31% 28% 12% 1	760
	11th to 20th	Night	15% 12% 26% 31% 15% 1	653
	21st to end	Night	8% 8% 25% 40% 18% 1	570
May	1st to 10th	Night	8% 8% 25% 38% 19% 2	570
	11th to 20th	Night	11% 3 23% 34% 24% 5%	561
	21st to end	Night	12% 2 14% 34% 32% 6%	617
June	1st to 10th	Night	11% 2 12% 39% 33% 3	570
	11th to 20th	Night	6% 2 13% 32% 35% 12%	570
	21st to end	Night	8% 2 8% 36% 39% 7%	570
July	1st to 10th	Night	9% 1 8% 28% 40% 13%	555
	11th to 20th	Night	8% 2 5% 26% 46% 13%	552
	21st to end	Night	7% 1 6% 31% 45% 10%	624
August	1st to 10th	Night	8% 1 8% 29% 42% 11%	567
	11th to 20th	Night	12% 1 7% 29% 42% 9%	564
	21st to end	Night	13% 3 8% 27% 39% 9%	674
September	1st to 10th	Night	11% 3 10% 29% 38% 9%	760
	11th to 20th	Night	15% 3 11% 29% 37% 5%	760
	21st to end	Night	14% 2 16% 31% 33% 4	760
October	1st to 10th	Night	14% 4 19% 32% 27% 5%	760
	11th to 20th	Night	14% 5% 20% 33% 24% 4	760
	21st to end	Night	12% 7% 23% 32% 23% 2	836
November	1st to 10th	Night	14% 7% 22% 33% 22% 2	780
	11th to 20th	Night	16% 12% 25% 31% 15% 2	800
	21st to end	Night	15% 11% 27% 31% 15% 1	800
December	1st to 10th	Night	19% 11% 30% 29% 11% 1	800
	11th to 20th	Night	20% 11% 28% 30% 10% 1	800
	21st to end	Night	26% 12% 24% 30% 8%	880

Page generated at 2025-03-24 09:04:33. Version ac07

Copyright © 2025 Attilla Danko.