Youngstown
Clear Sky Chart
History

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

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 9% 5% 5% 5% 4 5% 7% 29%	119485
	Night	17% 12% 4 10% 5% 4 4 3 5% 6% 30%	118721
Transparency	Day	53% 6% 11% 19% 10% 1	123146
	Night	54% 5% 10% 19% 10% 1	123198
Seeing	Day	23% 14% 28% 20% 11% 4	15344
	Night	22% 11% 26% 27% 11% 1	25133

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% 20% 7% 23% 6% 4 3 2 3 4 13%	4056
	11th to 20th	Day	12% 24% 8% 17% 9% 6% 5% 2 3 4 11%	4060
	21st to end	Day	21% 19% 8% 13% 7% 5% 4 2 4 4 12%	4466
February	1st to 10th	Day	19% 18% 6% 11% 8% 4 4 3 3 5% 20%	1800
	11th to 20th	Day	17% 14% 7% 13% 9% 5% 4 3 4 5% 20%	1753
	21st to end	Day	19% 14% 4 12% 5% 5% 4 4 6% 5% 23%	1650
March	1st to 10th	Day	17% 11% 6% 12% 5% 4 4 3 4 6% 28%	4927
	11th to 20th	Day	12% 10% 5% 10% 5% 5% 5% 3 5% 6% 36%	4980
	21st to end	Day	20% 11% 4 10% 5% 4 4 3 4 6% 28%	5465
April	1st to 10th	Day	16% 13% 4 8% 5% 4 5% 3 6% 7% 29%	2281
	11th to 20th	Day	18% 11% 3 8% 5% 4 4 4 5% 6% 32%	2467
	21st to end	Day	20% 12% 3 6% 5% 3 4 3 4 6% 34%	2600
May	1st to 10th	Day	21% 9% 3 8% 5% 5% 6% 4 5% 6% 28%	5862
	11th to 20th	Day	18% 9% 3 7% 5% 5% 5% 4 6% 8% 30%	5861
	21st to end	Day	18% 7% 3 6% 5% 5% 5% 4 6% 8% 33%	6747
June	1st to 10th	Day	14% 7% 2 7% 6% 5% 6% 4 7% 8% 34%	2786
	11th to 20th	Day	13% 7% 3 8% 6% 4 5% 4 5% 9% 36%	2660
	21st to end	Day	13% 5% 2 6% 4 5% 5% 5% 7% 10% 37%	2660
July	1st to 10th	Day	9% 6% 2 8% 5% 5% 5% 5% 6% 10% 39%	4265
	11th to 20th	Day	9% 5% 2 6% 5% 5% 6% 4 8% 9% 40%	4120
	21st to end	Day	11% 7% 3 7% 6% 5% 5% 4 7% 9% 36%	4466
August	1st to 10th	Day	14% 7% 3 8% 5% 6% 6% 4 6% 9% 30%	4104
	11th to 20th	Day	12% 7% 3 7% 5% 5% 6% 5% 8% 9% 33%	4044
	21st to end	Day	8% 5% 3 7% 5% 6% 7% 5% 6% 9% 39%	4381
September	1st to 10th	Day	14% 7% 2 6% 4 4 4 3 5% 6% 44%	2246
	11th to 20th	Day	11% 6% 3 6% 3 4 5% 4 6% 8% 43%	2090
	21st to end	Day	19% 9% 3 7% 4 4 4 3 5% 6% 35%	2090
October	1st to 10th	Day	15% 6% 3 7% 4 5% 5% 4 6% 8% 37%	1924
	11th to 20th	Day	20% 9% 3 8% 5% 4 4 4 5% 6% 32%	1900
	21st to end	Day	23% 10% 3 8% 4 5% 4 3 5% 6% 28%	2090
November	1st to 10th	Day	12% 9% 3 8% 5% 4 5% 4 5% 6% 40%	1819
	11th to 20th	Day	18% 15% 3 8% 4 4 4 5% 4 5% 28%	1691
	21st to end	Day	18% 18% 6% 9% 7% 4 4 3 5% 6% 21%	1600
December	1st to 10th	Day	21% 15% 8% 13% 5% 4 4 4 4 5% 17%	2600
	11th to 20th	Day	23% 20% 6% 10% 5% 3 3 3 4 5% 18%	2990
	21st to end	Day	24% 23% 7% 13% 6% 5% 3 2 3 4 9%	3984
January	1st to 10th	Night	15% 19% 8% 23% 5% 4 3 3 3 4 12%	5889
	11th to 20th	Night	12% 20% 10% 17% 8% 6% 5% 3 3 4 13%	5900
	21st to end	Night	23% 17% 7% 13% 7% 4 4 3 3 4 16%	6490
February	1st to 10th	Night	21% 15% 5% 11% 7% 5% 4 3 4 5% 21%	2600
	11th to 20th	Night	18% 14% 5% 13% 7% 6% 4 3 4 5% 21%	2528
	21st to end	Night	20% 13% 5% 12% 5% 5% 4 3 4 4 24%	1980
March	1st to 10th	Night	22% 13% 4 9% 4 4 4 2 3 5% 29%	4924
	11th to 20th	Night	14% 10% 4 8% 4 4 3 3 5% 6% 38%	4980
	21st to end	Night	18% 12% 3 8% 5% 5% 4 3 4 5% 33%	5467
April	1st to 10th	Night	18% 13% 3 8% 5% 4 5% 3 5% 7% 30%	2117
	11th to 20th	Night	16% 10% 3 7% 5% 5% 4 3 5% 7% 34%	1897
	21st to end	Night	16% 9% 3 6% 5% 4 4 3 5% 8% 36%	1800
May	1st to 10th	Night	26% 10% 3 8% 5% 4 4 4 4 6% 26%	4033
	11th to 20th	Night	16% 10% 3 7% 4 4 4 3 5% 7% 37%	4032
	21st to end	Night	18% 7% 2 6% 4 4 4 4 6% 9% 37%	4102
June	1st to 10th	Night	10% 6% 3 6% 5% 6% 5% 4 6% 7% 42%	1598
	11th to 20th	Night	10% 6% 3 7% 5% 4 4 4 6% 8% 44%	1520
	21st to end	Night	11% 5% 2 7% 5% 4 5% 4 7% 9% 41%	1520
July	1st to 10th	Night	10% 7% 2 7% 6% 4 4 3 5% 8% 42%	2677
	11th to 20th	Night	10% 5% 2 5% 4 4 5% 4 6% 9% 46%	2840
	21st to end	Night	8% 7% 2 7% 5% 5% 5% 4 6% 7% 43%	3087
August	1st to 10th	Night	12% 9% 3 8% 5% 4 5% 3 6% 6% 38%	2825
	11th to 20th	Night	13% 9% 3 7% 4 4 4 3 5% 6% 42%	2785
	21st to end	Night	8% 5% 2 6% 5% 5% 6% 5% 6% 8% 44%	3242
September	1st to 10th	Night	13% 6% 2 4 4 4 4 4 5% 7% 47%	1930
	11th to 20th	Night	11% 5% 1 4 4 3 4 4 6% 8% 51%	2090
	21st to end	Night	18% 8% 3 6% 4 4 5% 3 5% 7% 38%	2090
October	1st to 10th	Night	14% 5% 2 7% 3 4 4 3 5% 7% 44%	2256
	11th to 20th	Night	17% 7% 3 8% 5% 4 5% 3 6% 7% 35%	2280
	21st to end	Night	24% 9% 2 6% 4 4 3 4 5% 6% 34%	2508
November	1st to 10th	Night	14% 8% 3 6% 4 4 5% 3 4 7% 42%	2476
	11th to 20th	Night	18% 15% 4 7% 6% 4 4 3 4 5% 29%	2705
	21st to end	Night	20% 18% 3 7% 5% 4 4 3 5% 7% 25%	2800
December	1st to 10th	Night	17% 18% 8% 13% 7% 5% 4 3 4 5% 16%	4580
	11th to 20th	Night	20% 21% 8% 11% 5% 4 4 3 3 5% 18%	5205
	21st to end	Night	24% 19% 6% 12% 6% 4 4 3 4 5% 14%	6968

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	77% 4 7% 8% 4	4057
	11th to 20th	Day	78% 4 7% 8% 3	4060
	21st to end	Day	77% 4 7% 9% 3	4466
February	1st to 10th	Day	69% 3 8% 13% 6%	1800
	11th to 20th	Day	67% 5% 8% 13% 7%	1762
	21st to end	Day	62% 6% 10% 14% 7% 1	1650
March	1st to 10th	Day	57% 5% 10% 21% 7%	4927
	11th to 20th	Day	49% 5% 15% 23% 7% 1	4980
	21st to end	Day	56% 5% 8% 18% 12% 1	5465
April	1st to 10th	Day	53% 6% 11% 16% 12% 1	2281
	11th to 20th	Day	51% 6% 11% 17% 12% 2	2467
	21st to end	Day	51% 6% 10% 21% 10% 2	2600
May	1st to 10th	Day	54% 6% 10% 17% 9% 4	5897
	11th to 20th	Day	50% 7% 10% 21% 10% 1	5865
	21st to end	Day	46% 7% 12% 21% 12% 3	6762
June	1st to 10th	Day	45% 7% 13% 23% 11% 1	2786
	11th to 20th	Day	44% 7% 13% 22% 13% 1	2660
	21st to end	Day	40% 8% 13% 25% 13% 1	2660
July	1st to 10th	Day	40% 5% 13% 24% 14% 3	4200
	11th to 20th	Day	38% 5% 12% 27% 17% 1	4051
	21st to end	Day	43% 6% 13% 19% 17% 1	4324
August	1st to 10th	Day	48% 7% 13% 22% 10%	4091
	11th to 20th	Day	44% 7% 11% 29% 9% 1	4083
	21st to end	Day	39% 7% 13% 27% 12% 2	4381
September	1st to 10th	Day	40% 6% 11% 23% 17% 3	2246
	11th to 20th	Day	37% 7% 13% 25% 17% 1	2090
	21st to end	Day	48% 6% 12% 22% 11% 1	2090
October	1st to 10th	Day	33% 5% 13% 30% 18% 1	3197
	11th to 20th	Day	47% 4 10% 20% 14% 4	3140
	21st to end	Day	42% 3 13% 27% 15%	3428
November	1st to 10th	Day	43% 6% 12% 21% 16% 2	1819
	11th to 20th	Day	55% 7% 10% 17% 8% 3	1691
	21st to end	Day	63% 5% 11% 15% 6% 1	1600
December	1st to 10th	Day	70% 4 11% 12% 2	2600
	11th to 20th	Day	70% 4 9% 13% 4	2986
	21st to end	Day	79% 3 7% 8% 2	3984
January	1st to 10th	Night	75% 4 7% 9% 4	5889
	11th to 20th	Night	76% 4 8% 9% 3	5900
	21st to end	Night	73% 3 8% 10% 5% 1	6490
February	1st to 10th	Night	66% 5% 9% 15% 5%	2600
	11th to 20th	Night	64% 5% 9% 16% 5%	2530
	21st to end	Night	63% 5% 8% 14% 9% 1	1980
March	1st to 10th	Night	59% 3 11% 19% 8%	4924
	11th to 20th	Night	46% 5% 14% 24% 9% 2	4980
	21st to end	Night	53% 5% 9% 18% 15% 1	5467
April	1st to 10th	Night	54% 6% 10% 17% 13% 2	2117
	11th to 20th	Night	49% 6% 12% 17% 14% 2	1897
	21st to end	Night	45% 6% 12% 21% 14% 2	1800
May	1st to 10th	Night	59% 5% 8% 15% 9% 4	4060
	11th to 20th	Night	47% 6% 9% 24% 13% 2	4033
	21st to end	Night	43% 6% 13% 24% 13% 2	4109
June	1st to 10th	Night	40% 7% 11% 23% 16% 2	1598
	11th to 20th	Night	37% 7% 15% 23% 16% 2	1520
	21st to end	Night	38% 8% 13% 23% 17% 1	1520
July	1st to 10th	Night	41% 6% 11% 22% 19% 2	2633
	11th to 20th	Night	34% 5% 14% 30% 16% 1	2786
	21st to end	Night	39% 6% 13% 18% 23% 2	2988
August	1st to 10th	Night	46% 6% 12% 23% 13% 1	2814
	11th to 20th	Night	41% 6% 11% 29% 13% 1	2812
	21st to end	Night	36% 6% 13% 30% 13% 2	3242
September	1st to 10th	Night	34% 7% 11% 25% 19% 4	1930
	11th to 20th	Night	30% 7% 15% 24% 22% 2	2090
	21st to end	Night	44% 6% 12% 21% 16% 1	2090
October	1st to 10th	Night	35% 4 9% 28% 23% 1	3763
	11th to 20th	Night	40% 5% 12% 23% 13% 7%	3779
	21st to end	Night	38% 4 11% 30% 17% 1	4120
November	1st to 10th	Night	41% 5% 12% 23% 15% 3	2476
	11th to 20th	Night	56% 6% 9% 18% 8% 3	2705
	21st to end	Night	59% 5% 12% 18% 5% 1	2800
December	1st to 10th	Night	70% 4 12% 11% 3	4580
	11th to 20th	Night	70% 4 10% 14% 2	5208
	21st to end	Night	73% 5% 10% 11% 2	6968

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	33% 24% 30% 10% 4	300
	11th to 20th	Day	32% 26% 31% 8% 3	300
	21st to end	Day	28% 26% 33% 10% 2 1	330
February	1st to 10th	Day	31% 19% 40% 8% 1	300
	11th to 20th	Day	32% 26% 31% 9% 2	300
	21st to end	Day	31% 24% 35% 9%	249
March	1st to 10th	Day	28% 18% 34% 16% 3	492
	11th to 20th	Day	30% 17% 31% 16% 4 1	500
	21st to end	Day	35% 17% 27% 16% 4 1	550
April	1st to 10th	Day	27% 22% 27% 16% 6% 1	500
	11th to 20th	Day	29% 16% 26% 17% 8% 4	492
	21st to end	Day	26% 17% 31% 18% 6% 2	500
May	1st to 10th	Day	29% 19% 26% 16% 8% 3	503
	11th to 20th	Day	21% 14% 32% 22% 9% 3	527
	21st to end	Day	18% 10% 24% 27% 16% 5%	573
June	1st to 10th	Day	16% 10% 34% 25% 11% 4	526
	11th to 20th	Day	19% 9% 26% 27% 16% 3	490
	21st to end	Day	16% 9% 33% 24% 14% 3	490
July	1st to 10th	Day	13% 6% 19% 28% 24% 11%	485
	11th to 20th	Day	13% 6% 26% 28% 18% 8%	484
	21st to end	Day	14% 4 25% 28% 20% 9%	532
August	1st to 10th	Day	14% 7% 20% 30% 19% 10%	486
	11th to 20th	Day	16% 5% 22% 26% 19% 11%	479
	21st to end	Day	11% 5% 22% 29% 21% 12%	539
September	1st to 10th	Day	14% 8% 21% 26% 20% 10%	490
	11th to 20th	Day	10% 5% 20% 30% 26% 10%	490
	21st to end	Day	25% 11% 24% 21% 14% 6%	490
October	1st to 10th	Day	15% 9% 26% 25% 19% 6%	490
	11th to 20th	Day	22% 14% 34% 19% 8% 2	490
	21st to end	Day	28% 15% 30% 20% 6%	539
November	1st to 10th	Day	18% 22% 33% 15% 10% 1	357
	11th to 20th	Day	32% 17% 30% 14% 6% 1	245
	21st to end	Day	31% 17% 40% 12% 1	200
December	1st to 10th	Day	34% 23% 30% 11% 3 1	200
	11th to 20th	Day	35% 15% 36% 11% 4	200
	21st to end	Day	37% 17% 32% 13% 1	226
January	1st to 10th	Night	27% 19% 34% 17% 3	800
	11th to 20th	Night	30% 18% 31% 18% 4	800
	21st to end	Night	28% 18% 30% 21% 3	880
February	1st to 10th	Night	30% 16% 29% 22% 3	800
	11th to 20th	Night	29% 16% 34% 19% 2	783
	21st to end	Night	29% 14% 35% 19% 3	660
March	1st to 10th	Night	26% 15% 31% 25% 3	800
	11th to 20th	Night	24% 15% 29% 25% 6% 1	800
	21st to end	Night	24% 14% 33% 23% 5% 1	880
April	1st to 10th	Night	27% 14% 30% 24% 6%	800
	11th to 20th	Night	23% 13% 32% 24% 8% 1	713
	21st to end	Night	20% 9% 35% 31% 6%	600
May	1st to 10th	Night	23% 9% 24% 32% 10% 1	600
	11th to 20th	Night	20% 7% 24% 36% 12% 1	591
	21st to end	Night	12% 4 24% 38% 19% 3	512
June	1st to 10th	Night	12% 5% 26% 41% 16%	400
	11th to 20th	Night	12% 6% 23% 45% 14% 1	380
	21st to end	Night	10% 4 26% 41% 19% 1	380
July	1st to 10th	Night	8% 3 15% 44% 24% 5%	458
	11th to 20th	Night	10% 3 18% 38% 27% 4	552
	21st to end	Night	12% 2 13% 43% 29% 2	624
August	1st to 10th	Night	12% 3 14% 42% 27% 2	567
	11th to 20th	Night	16% 2 12% 37% 29% 4	564
	21st to end	Night	12% 2 18% 33% 29% 5%	693
September	1st to 10th	Night	16% 4 17% 33% 25% 4	760
	11th to 20th	Night	13% 3 14% 35% 29% 5%	760
	21st to end	Night	20% 8% 23% 26% 19% 4	760
October	1st to 10th	Night	17% 8% 25% 28% 20% 3	760
	11th to 20th	Night	21% 11% 30% 27% 10% 1	760
	21st to end	Night	28% 10% 28% 27% 6%	836
November	1st to 10th	Night	19% 10% 30% 28% 11% 1	780
	11th to 20th	Night	28% 15% 29% 21% 7% 1	800
	21st to end	Night	30% 15% 29% 21% 5%	800
December	1st to 10th	Night	32% 18% 27% 18% 5%	800
	11th to 20th	Night	29% 18% 29% 20% 4	800
	21st to end	Night	30% 16% 31% 21% 2	880

Page generated at 2025-06-07 10:28:13. Version ac07

Copyright © 2025 Attilla Danko.