State Camp
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the State Camp clear sky chart from 2005-11-06 to 2024-11-10.

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	17% 10% 3 8% 5% 5% 5% 4 5% 7% 32%	101458
	Night	17% 10% 3 8% 5% 4 4 3 5% 7% 33%	97692
Transparency	Day	48% 7% 12% 21% 10% 1	105063
	Night	47% 7% 12% 20% 11% 1	102175
Seeing	Day	24% 16% 27% 19% 11% 3	14757
	Night	22% 14% 25% 27% 11% 1	24157

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	15% 18% 7% 10% 5% 4 3 3 3 4 27%	2517
	11th to 20th	Day	11% 16% 9% 17% 7% 4 4 3 4 5% 19%	2781
	21st to end	Day	23% 17% 8% 11% 5% 4 4 3 3 4 19%	3124
February	1st to 10th	Day	17% 15% 6% 11% 7% 5% 4 3 5% 4 23%	1710
	11th to 20th	Day	14% 13% 6% 10% 7% 5% 4 4 5% 6% 27%	1663
	21st to end	Day	19% 13% 3 9% 7% 4 3 3 4 5% 29%	1549
March	1st to 10th	Day	22% 12% 4 7% 5% 4 4 3 4 6% 30%	3392
	11th to 20th	Day	12% 13% 5% 9% 5% 5% 4 3 4 5% 34%	3480
	21st to end	Day	15% 10% 3 8% 6% 5% 4 3 4 5% 36%	3861
April	1st to 10th	Day	17% 13% 3 9% 5% 4 4 3 5% 6% 32%	2280
	11th to 20th	Day	17% 11% 3 6% 5% 3 5% 5% 5% 5% 34%	2254
	21st to end	Day	21% 9% 3 7% 5% 4 4 3 5% 5% 34%	2361
May	1st to 10th	Day	27% 7% 2 7% 5% 3 4 3 5% 7% 29%	4108
	11th to 20th	Day	25% 9% 3 8% 5% 4 4 4 5% 6% 28%	4386
	21st to end	Day	14% 6% 2 6% 5% 5% 5% 4 6% 8% 38%	4837
June	1st to 10th	Day	15% 7% 3 7% 6% 6% 5% 4 6% 7% 34%	2660
	11th to 20th	Day	15% 7% 2 7% 6% 4 5% 4 7% 8% 35%	2660
	21st to end	Day	13% 6% 3 5% 6% 4 6% 4 6% 10% 36%	2660
July	1st to 10th	Day	8% 6% 3 8% 6% 6% 6% 5% 7% 9% 36%	4440
	11th to 20th	Day	7% 7% 3 8% 6% 5% 6% 5% 7% 9% 37%	4440
	21st to end	Day	11% 7% 3 8% 5% 5% 6% 5% 7% 8% 37%	4479
August	1st to 10th	Day	20% 7% 2 7% 5% 5% 5% 4 6% 9% 30%	4104
	11th to 20th	Day	14% 8% 3 8% 5% 6% 6% 5% 7% 8% 30%	4012
	21st to end	Day	15% 6% 2 5% 4 4 5% 3 7% 10% 39%	4180
September	1st to 10th	Day	18% 6% 2 6% 5% 4 5% 3 4 6% 42%	2280
	11th to 20th	Day	15% 6% 2 5% 5% 3 4 3 4 7% 45%	2275
	21st to end	Day	24% 6% 3 5% 5% 4 4 3 5% 6% 35%	1985
October	1st to 10th	Day	16% 8% 3 8% 4 4 4 4 6% 8% 36%	1900
	11th to 20th	Day	20% 8% 3 7% 5% 4 5% 4 5% 6% 34%	1900
	21st to end	Day	19% 9% 3 8% 6% 5% 5% 4 5% 6% 32%	2090
November	1st to 10th	Day	12% 8% 4 7% 5% 4 4 3 5% 6% 42%	1809
	11th to 20th	Day	16% 13% 3 8% 6% 5% 4 4 6% 6% 29%	1563
	21st to end	Day	19% 15% 3 8% 6% 4 4 3 4 7% 28%	1520
December	1st to 10th	Day	19% 15% 6% 11% 7% 5% 4 3 4 5% 19%	1520
	11th to 20th	Day	20% 14% 5% 10% 5% 4 4 4 5% 6% 23%	1906
	21st to end	Day	24% 17% 5% 11% 6% 5% 4 3 4 5% 16%	2772
January	1st to 10th	Night	15% 16% 5% 10% 5% 4 5% 4 5% 7% 24%	4429
	11th to 20th	Night	16% 15% 6% 14% 5% 5% 5% 4 5% 6% 20%	4175
	21st to end	Night	24% 14% 5% 11% 6% 4 4 3 4 4 20%	4532
February	1st to 10th	Night	16% 12% 5% 9% 6% 5% 5% 3 5% 6% 28%	2470
	11th to 20th	Night	16% 11% 4 8% 6% 5% 5% 5% 5% 6% 29%	2403
	21st to end	Night	18% 11% 4 9% 6% 4 4 3 5% 5% 29%	1903
March	1st to 10th	Night	23% 14% 3 7% 4 4 4 3 4 5% 30%	3446
	11th to 20th	Night	12% 13% 7% 8% 5% 5% 4 3 5% 6% 31%	3479
	21st to end	Night	15% 10% 2 7% 4 4 4 3 5% 5% 41%	3770
April	1st to 10th	Night	18% 14% 3 7% 5% 3 4 4 4 7% 31%	1900
	11th to 20th	Night	17% 9% 3 6% 5% 4 4 4 5% 6% 37%	1875
	21st to end	Night	19% 7% 3 6% 4 5% 5% 4 5% 7% 36%	1836
May	1st to 10th	Night	28% 9% 2 6% 4 4 4 3 3 5% 31%	2833
	11th to 20th	Night	25% 10% 3 7% 4 4 4 3 4 6% 30%	2505
	21st to end	Night	14% 7% 2 8% 5% 4 5% 4 7% 8% 38%	2738
June	1st to 10th	Night	14% 7% 2 5% 4 5% 4 3 5% 9% 43%	1520
	11th to 20th	Night	11% 7% 2 7% 4 5% 4 4 6% 10% 41%	1520
	21st to end	Night	12% 6% 3 5% 5% 4 5% 4 8% 8% 41%	1520
July	1st to 10th	Night	9% 7% 3 7% 5% 5% 5% 4 7% 8% 40%	2520
	11th to 20th	Night	6% 5% 2 6% 5% 6% 6% 4 7% 10% 43%	2520
	21st to end	Night	12% 6% 3 8% 5% 4 5% 3 5% 7% 42%	3070
August	1st to 10th	Night	19% 6% 2 5% 5% 4 5% 4 6% 8% 36%	2825
	11th to 20th	Night	17% 7% 3 7% 3 4 4 4 5% 6% 40%	2785
	21st to end	Night	15% 5% 2 5% 4 4 4 4 5% 7% 46%	3475
September	1st to 10th	Night	16% 5% 3 6% 4 4 4 3 5% 6% 45%	1900
	11th to 20th	Night	15% 5% 2 4 4 3 3 2 5% 7% 51%	1901
	21st to end	Night	21% 5% 2 6% 5% 4 4 3 6% 6% 38%	2194
October	1st to 10th	Night	18% 6% 2 6% 4 4 3 3 5% 6% 43%	2280
	11th to 20th	Night	19% 7% 2 6% 4 4 4 4 4 7% 40%	2280
	21st to end	Night	22% 9% 3 6% 4 3 4 3 5% 8% 34%	2508
November	1st to 10th	Night	11% 8% 2 7% 3 3 4 4 5% 7% 46%	2474
	11th to 20th	Night	18% 10% 3 8% 5% 5% 4 4 5% 6% 31%	2614
	21st to end	Night	16% 12% 4 8% 5% 4 4 3 6% 7% 29%	2660
December	1st to 10th	Night	18% 14% 4 10% 6% 5% 5% 5% 6% 6% 21%	2660
	11th to 20th	Night	19% 12% 4 9% 6% 6% 5% 3 4 6% 27%	3288
	21st to end	Night	23% 14% 5% 10% 5% 5% 5% 3 5% 7% 19%	4884

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	59% 6% 12% 15% 4 2	2518
	11th to 20th	Day	67% 6% 8% 13% 5% 1	2781
	21st to end	Day	69% 6% 8% 12% 4 1	3124
February	1st to 10th	Day	63% 5% 11% 14% 7% 1	1710
	11th to 20th	Day	56% 6% 10% 20% 8% 1	1672
	21st to end	Day	58% 4 9% 19% 8% 2	1549
March	1st to 10th	Day	53% 7% 10% 22% 6% 1	3395
	11th to 20th	Day	48% 8% 15% 18% 8% 2	3480
	21st to end	Day	46% 9% 10% 21% 13% 2	3861
April	1st to 10th	Day	53% 5% 10% 19% 11% 2	2280
	11th to 20th	Day	48% 7% 11% 18% 14% 2	2254
	21st to end	Day	50% 6% 9% 19% 13% 3	2361
May	1st to 10th	Day	53% 7% 8% 21% 9% 1	4120
	11th to 20th	Day	54% 9% 11% 16% 7% 2	4390
	21st to end	Day	38% 10% 13% 25% 12% 2	4837
June	1st to 10th	Day	46% 7% 13% 19% 13% 1	2660
	11th to 20th	Day	43% 8% 15% 20% 13% 1	2660
	21st to end	Day	40% 8% 15% 24% 12%	2660
July	1st to 10th	Day	41% 8% 16% 23% 11% 1	4370
	11th to 20th	Day	38% 9% 16% 24% 13%	4365
	21st to end	Day	41% 9% 13% 24% 13% 1	4336
August	1st to 10th	Day	49% 8% 14% 20% 9%	4091
	11th to 20th	Day	46% 8% 13% 25% 7%	4051
	21st to end	Day	39% 6% 13% 29% 11% 2	4180
September	1st to 10th	Day	44% 5% 10% 24% 15% 2	2280
	11th to 20th	Day	38% 6% 11% 24% 19% 2	2275
	21st to end	Day	49% 5% 12% 18% 15% 1	1985
October	1st to 10th	Day	40% 7% 11% 23% 16% 3	3160
	11th to 20th	Day	40% 7% 10% 22% 17% 3	3140
	21st to end	Day	35% 6% 16% 28% 14% 1	3428
November	1st to 10th	Day	42% 6% 12% 23% 14% 3	1809
	11th to 20th	Day	53% 7% 12% 18% 7% 2	1563
	21st to end	Day	55% 6% 13% 19% 7% 1	1520
December	1st to 10th	Day	66% 6% 12% 11% 5%	1520
	11th to 20th	Day	59% 6% 13% 16% 5%	1906
	21st to end	Day	69% 8% 10% 11% 2	2772
January	1st to 10th	Night	56% 9% 12% 18% 5% 1	4429
	11th to 20th	Night	62% 7% 12% 13% 4 1	4175
	21st to end	Night	67% 6% 9% 13% 5% 1	4532
February	1st to 10th	Night	54% 7% 13% 18% 7%	2470
	11th to 20th	Night	53% 7% 12% 19% 9%	2405
	21st to end	Night	56% 5% 10% 17% 10% 1	1903
March	1st to 10th	Night	55% 7% 10% 21% 7% 1	3456
	11th to 20th	Night	48% 9% 15% 19% 8% 1	3480
	21st to end	Night	43% 6% 8% 22% 18% 3	3770
April	1st to 10th	Night	52% 6% 10% 18% 13% 1	1900
	11th to 20th	Night	46% 7% 11% 20% 13% 2	1875
	21st to end	Night	45% 7% 12% 21% 14% 2	1836
May	1st to 10th	Night	56% 6% 9% 19% 8% 2	2840
	11th to 20th	Night	53% 10% 13% 14% 10% 1	2506
	21st to end	Night	38% 12% 14% 19% 13% 5%	2739
June	1st to 10th	Night	38% 8% 13% 24% 15% 1	1520
	11th to 20th	Night	38% 9% 14% 24% 14% 2	1520
	21st to end	Night	37% 9% 13% 27% 13% 1	1520
July	1st to 10th	Night	38% 8% 14% 21% 16% 2	2480
	11th to 20th	Night	32% 10% 17% 25% 16% 1	2472
	21st to end	Night	40% 7% 13% 19% 20% 1	2972
August	1st to 10th	Night	44% 10% 14% 23% 9%	2814
	11th to 20th	Night	41% 8% 12% 27% 11%	2812
	21st to end	Night	36% 7% 12% 32% 11% 2	3475
September	1st to 10th	Night	39% 6% 11% 25% 16% 3	1900
	11th to 20th	Night	33% 6% 13% 27% 20% 2	1901
	21st to end	Night	45% 6% 13% 21% 15% 1	2194
October	1st to 10th	Night	40% 6% 11% 23% 19% 1	3800
	11th to 20th	Night	35% 7% 11% 23% 18% 5%	3779
	21st to end	Night	35% 6% 16% 26% 16% 2	4120
November	1st to 10th	Night	37% 6% 15% 24% 17% 2	2474
	11th to 20th	Night	50% 6% 12% 19% 10% 2	2614
	21st to end	Night	51% 6% 15% 20% 7% 1	2660
December	1st to 10th	Night	59% 9% 13% 15% 5%	2660
	11th to 20th	Night	57% 6% 12% 19% 6%	3288
	21st to end	Night	62% 9% 13% 13% 3	4884

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	34% 22% 31% 7% 5% 1	180
	11th to 20th	Day	37% 25% 25% 11% 1	255
	21st to end	Day	31% 30% 26% 10% 3 1	297
February	1st to 10th	Day	33% 29% 27% 10% 1	270
	11th to 20th	Day	38% 25% 32% 4	270
	21st to end	Day	39% 20% 26% 13% 2	361
March	1st to 10th	Day	31% 21% 29% 15% 3	460
	11th to 20th	Day	31% 24% 26% 14% 3 2	460
	21st to end	Day	32% 22% 27% 12% 5% 2	506
April	1st to 10th	Day	31% 25% 23% 15% 5% 1	460
	11th to 20th	Day	29% 23% 21% 15% 8% 4	452
	21st to end	Day	28% 16% 34% 13% 8% 1	460
May	1st to 10th	Day	32% 19% 23% 15% 9% 3	463
	11th to 20th	Day	25% 16% 27% 20% 8% 4	487
	21st to end	Day	20% 12% 27% 21% 16% 4	529
June	1st to 10th	Day	17% 14% 30% 24% 12% 2	490
	11th to 20th	Day	18% 14% 25% 27% 14% 2	490
	21st to end	Day	16% 13% 33% 24% 11% 3	490
July	1st to 10th	Day	12% 8% 28% 27% 17% 8%	485
	11th to 20th	Day	6% 10% 30% 31% 17% 6%	484
	21st to end	Day	13% 7% 33% 25% 15% 6%	532
August	1st to 10th	Day	12% 7% 26% 27% 20% 7%	486
	11th to 20th	Day	14% 8% 25% 28% 16% 8%	479
	21st to end	Day	17% 8% 26% 22% 16% 10%	539
September	1st to 10th	Day	19% 11% 21% 24% 18% 7%	490
	11th to 20th	Day	16% 6% 22% 23% 24% 9%	490
	21st to end	Day	29% 10% 23% 20% 15% 4	490
October	1st to 10th	Day	23% 12% 22% 20% 19% 4	490
	11th to 20th	Day	25% 16% 29% 19% 8% 3	490
	21st to end	Day	27% 17% 27% 19% 8% 1	539
November	1st to 10th	Day	22% 17% 27% 20% 13% 2	422
	11th to 20th	Day	26% 26% 26% 15% 7%	223
	21st to end	Day	29% 25% 33% 9% 4	180
December	1st to 10th	Day	34% 27% 23% 11% 4 1	180
	11th to 20th	Day	38% 19% 27% 14% 2	180
	21st to end	Day	43% 16% 27% 11% 4	198
January	1st to 10th	Night	25% 23% 33% 16% 3	760
	11th to 20th	Night	28% 21% 28% 19% 4	760
	21st to end	Night	25% 22% 30% 20% 2	836
February	1st to 10th	Night	27% 20% 31% 21% 2	760
	11th to 20th	Night	28% 24% 33% 14% 1	743
	21st to end	Night	31% 19% 29% 19% 2	628
March	1st to 10th	Night	27% 19% 31% 20% 3	760
	11th to 20th	Night	27% 21% 26% 20% 5% 1	760
	21st to end	Night	22% 21% 32% 20% 5% 1	836
April	1st to 10th	Night	28% 20% 28% 20% 5%	760
	11th to 20th	Night	24% 16% 28% 24% 8% 1	751
	21st to end	Night	23% 14% 26% 30% 7%	696
May	1st to 10th	Night	24% 10% 22% 30% 13%	570
	11th to 20th	Night	18% 11% 24% 38% 9%	384
	21st to end	Night	15% 7% 23% 33% 22% 1	411
June	1st to 10th	Night	14% 8% 20% 41% 16% 1	380
	11th to 20th	Night	13% 7% 22% 42% 17%	380
	21st to end	Night	11% 4 27% 41% 17%	380
July	1st to 10th	Night	15% 5% 18% 39% 21% 2	370
	11th to 20th	Night	6% 3 20% 44% 27% 1	368
	21st to end	Night	12% 4 19% 40% 24% 2	607
August	1st to 10th	Night	11% 3 15% 41% 27% 2	567
	11th to 20th	Night	13% 6% 12% 38% 26% 4	564
	21st to end	Night	13% 4 17% 34% 29% 2	835
September	1st to 10th	Night	18% 6% 20% 31% 23% 3	760
	11th to 20th	Night	16% 4 19% 27% 29% 5%	760
	21st to end	Night	23% 9% 17% 29% 19% 3	760
October	1st to 10th	Night	20% 10% 20% 28% 19% 3	760
	11th to 20th	Night	22% 14% 23% 29% 10% 1	760
	21st to end	Night	25% 16% 24% 28% 6%	836
November	1st to 10th	Night	17% 13% 28% 32% 10% 1	779
	11th to 20th	Night	27% 16% 24% 25% 6% 2	760
	21st to end	Night	24% 17% 28% 26% 5%	760
December	1st to 10th	Night	28% 21% 30% 16% 5%	760
	11th to 20th	Night	28% 17% 28% 22% 4	760
	21st to end	Night	27% 18% 29% 25% 2	836

Page generated at 2024-11-07 06:55:47. Version ac07

Copyright © 2024 Attilla Danko.