Edja Lake
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Edja Lake clear sky chart from 2005-11-06 to 2024-11-01.

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% 6% 31%	101552
	Night	17% 12% 4 9% 5% 4 4 3 5% 6% 30%	97364
Transparency	Day	53% 6% 12% 20% 9% 1	101310
	Night	55% 6% 12% 18% 8% 1	97226
Seeing	Day	24% 15% 30% 20% 9% 2	14391
	Night	23% 12% 28% 26% 10% 1	23438

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	16% 20% 7% 16% 8% 4 4 2 3 3 18%	2517
	11th to 20th	Day	13% 14% 5% 19% 8% 6% 4 3 3 4 22%	2520
	21st to end	Day	13% 19% 8% 13% 7% 5% 5% 3 4 4 18%	2850
February	1st to 10th	Day	12% 17% 6% 14% 7% 5% 3 4 5% 5% 21%	1710
	11th to 20th	Day	13% 17% 5% 12% 6% 4 4 2 4 5% 26%	1663
	21st to end	Day	17% 17% 4 9% 7% 5% 4 2 4 5% 26%	1551
March	1st to 10th	Day	17% 18% 4 9% 5% 4 4 3 4 5% 26%	3133
	11th to 20th	Day	12% 19% 7% 11% 6% 4 5% 3 4 4 26%	3480
	21st to end	Day	12% 8% 3 8% 6% 5% 4 3 5% 6% 40%	4024
April	1st to 10th	Day	22% 14% 3 8% 5% 4 3 3 4 4 30%	2280
	11th to 20th	Day	23% 11% 3 7% 5% 3 3 3 4 5% 33%	2254
	21st to end	Day	22% 11% 4 8% 4 4 4 3 4 4 31%	2461
May	1st to 10th	Day	19% 10% 3 8% 5% 5% 5% 4 5% 7% 30%	4426
	11th to 20th	Day	17% 8% 3 7% 5% 4 4 3 6% 8% 34%	4398
	21st to end	Day	16% 8% 3 7% 5% 5% 5% 4 6% 7% 36%	4837
June	1st to 10th	Day	21% 8% 3 9% 5% 5% 6% 4 6% 6% 27%	2660
	11th to 20th	Day	15% 6% 2 6% 5% 4 5% 4 7% 7% 37%	2660
	21st to end	Day	18% 7% 2 7% 7% 5% 5% 4 7% 7% 29%	2660
July	1st to 10th	Day	13% 8% 2 7% 6% 6% 5% 5% 7% 9% 31%	4440
	11th to 20th	Day	13% 7% 3 7% 5% 5% 5% 4 6% 8% 37%	4440
	21st to end	Day	11% 6% 2 6% 4 4 4 4 6% 8% 43%	4814
August	1st to 10th	Day	12% 7% 3 9% 6% 6% 7% 5% 8% 8% 31%	4378
	11th to 20th	Day	16% 7% 2 7% 5% 5% 5% 4 6% 7% 36%	4030
	21st to end	Day	12% 6% 2 8% 4 5% 5% 5% 7% 9% 37%	4180
September	1st to 10th	Day	15% 6% 2 6% 5% 4 4 4 5% 7% 42%	2280
	11th to 20th	Day	14% 7% 2 6% 4 4 4 3 5% 7% 43%	2280
	21st to end	Day	20% 7% 2 6% 5% 4 4 3 5% 8% 35%	2021
October	1st to 10th	Day	20% 9% 2 8% 4 4 4 4 4 6% 34%	1900
	11th to 20th	Day	24% 12% 3 8% 5% 4 4 3 5% 5% 26%	1900
	21st to end	Day	25% 12% 2 9% 4 4 4 3 6% 6% 24%	1929
November	1st to 10th	Day	15% 13% 4 8% 5% 4 4 4 5% 6% 33%	1638
	11th to 20th	Day	19% 15% 5% 11% 7% 4 4 4 5% 5% 22%	1520
	21st to end	Day	23% 18% 5% 13% 4 4 5% 3 3 4 18%	1520
December	1st to 10th	Day	22% 21% 5% 10% 6% 5% 4 3 4 4 15%	1520
	11th to 20th	Day	20% 17% 6% 10% 5% 5% 5% 4 5% 4 18%	1906
	21st to end	Day	26% 20% 5% 13% 4 2 3 2 2 4 18%	2772
January	1st to 10th	Night	16% 20% 6% 13% 6% 4 4 3 4 4 20%	4429
	11th to 20th	Night	13% 15% 6% 15% 7% 5% 4 3 5% 5% 23%	4440
	21st to end	Night	13% 19% 8% 12% 7% 6% 5% 3 3 4 19%	4788
February	1st to 10th	Night	12% 16% 6% 13% 7% 6% 5% 3 4 5% 22%	2470
	11th to 20th	Night	13% 15% 5% 12% 6% 5% 5% 4 4 4 25%	2403
	21st to end	Night	13% 16% 5% 10% 6% 5% 3 3 6% 5% 26%	1903
March	1st to 10th	Night	20% 14% 4 8% 6% 4 4 2 4 5% 29%	3705
	11th to 20th	Night	16% 19% 5% 11% 5% 4 4 3 4 5% 24%	3479
	21st to end	Night	12% 9% 4 10% 5% 4 4 3 5% 6% 39%	3608
April	1st to 10th	Night	22% 11% 3 7% 5% 4 3 3 5% 6% 30%	1900
	11th to 20th	Night	19% 10% 3 5% 5% 3 3 4 5% 5% 37%	1875
	21st to end	Night	22% 11% 3 7% 5% 4 3 3 4 5% 34%	1735
May	1st to 10th	Night	20% 11% 4 8% 4 4 5% 4 5% 6% 29%	2514
	11th to 20th	Night	17% 8% 3 8% 4 4 5% 4 6% 6% 34%	2495
	21st to end	Night	15% 9% 3 7% 5% 4 5% 4 6% 7% 35%	2738
June	1st to 10th	Night	18% 8% 2 6% 5% 4 4 4 7% 8% 33%	1520
	11th to 20th	Night	15% 7% 2 7% 5% 4 4 4 5% 7% 40%	1520
	21st to end	Night	17% 7% 2 7% 6% 5% 4 3 5% 7% 36%	1520
July	1st to 10th	Night	12% 8% 3 8% 5% 6% 6% 4 7% 7% 34%	2520
	11th to 20th	Night	13% 8% 3 7% 4 4 5% 4 7% 8% 38%	2520
	21st to end	Night	9% 6% 2 6% 4 4 4 4 6% 8% 46%	2739
August	1st to 10th	Night	12% 6% 3 7% 5% 5% 5% 4 7% 8% 38%	2535
	11th to 20th	Night	16% 7% 2 5% 4 4 5% 4 6% 9% 38%	2785
	21st to end	Night	16% 6% 3 7% 4 4 4 4 7% 7% 38%	3444
September	1st to 10th	Night	13% 6% 3 7% 4 4 4 3 6% 6% 45%	1900
	11th to 20th	Night	15% 6% 2 5% 3 3 3 3 5% 8% 47%	1900
	21st to end	Night	19% 7% 2 7% 4 4 3 3 4 7% 40%	2156
October	1st to 10th	Night	20% 9% 2 6% 4 4 3 3 5% 6% 39%	2280
	11th to 20th	Night	22% 10% 4 8% 6% 5% 4 3 4 6% 29%	2280
	21st to end	Night	24% 10% 4 7% 5% 5% 4 3 5% 6% 27%	2667
November	1st to 10th	Night	18% 12% 4 9% 5% 5% 4 3 4 6% 30%	2444
	11th to 20th	Night	19% 13% 4 10% 6% 5% 5% 4 4 5% 26%	2660
	21st to end	Night	23% 17% 4 10% 6% 4 4 4 5% 5% 19%	2660
December	1st to 10th	Night	20% 20% 6% 11% 6% 4 4 3 4 4 17%	2660
	11th to 20th	Night	21% 16% 6% 10% 5% 4 3 3 3 5% 23%	3288
	21st to end	Night	25% 22% 6% 12% 4 3 3 2 3 3 18%	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	70% 6% 9% 10% 4	2518
	11th to 20th	Day	67% 5% 8% 13% 6%	2520
	21st to end	Day	69% 6% 9% 10% 5% 1	2850
February	1st to 10th	Day	65% 5% 9% 14% 6% 1	1710
	11th to 20th	Day	62% 4 12% 13% 9% 1	1672
	21st to end	Day	62% 4 9% 14% 10% 1	1551
March	1st to 10th	Day	60% 6% 9% 15% 10% 1	3136
	11th to 20th	Day	61% 5% 10% 14% 8% 2	3480
	21st to end	Day	43% 6% 8% 24% 16% 2	4024
April	1st to 10th	Day	58% 4 8% 17% 10% 3	2280
	11th to 20th	Day	53% 4 7% 21% 12% 2	2254
	21st to end	Day	56% 5% 7% 16% 12% 3	2461
May	1st to 10th	Day	51% 7% 10% 20% 10% 2	4440
	11th to 20th	Day	46% 8% 13% 22% 10% 1	4402
	21st to end	Day	47% 7% 11% 18% 15% 2	4837
June	1st to 10th	Day	55% 6% 11% 17% 10% 1	2660
	11th to 20th	Day	43% 7% 12% 25% 11% 2	2660
	21st to end	Day	51% 8% 12% 19% 9%	2660
July	1st to 10th	Day	47% 5% 15% 26% 8%	4370
	11th to 20th	Day	45% 4 16% 27% 7%	4365
	21st to end	Day	39% 5% 15% 31% 9%	4661
August	1st to 10th	Day	50% 6% 15% 23% 7%	4364
	11th to 20th	Day	47% 5% 15% 27% 6%	4069
	21st to end	Day	42% 5% 16% 24% 12% 1	4180
September	1st to 10th	Day	41% 6% 14% 26% 12%	2280
	11th to 20th	Day	40% 7% 13% 29% 11% 1	2280
	21st to end	Day	46% 7% 14% 24% 9%	2021
October	1st to 10th	Day	51% 6% 12% 22% 9%	1900
	11th to 20th	Day	59% 7% 13% 16% 4 1	1900
	21st to end	Day	60% 5% 14% 14% 6% 1	1929
November	1st to 10th	Day	50% 7% 13% 23% 6% 1	1638
	11th to 20th	Day	63% 7% 12% 12% 6%	1520
	21st to end	Day	71% 5% 10% 8% 5%	1520
December	1st to 10th	Day	72% 6% 10% 9% 3	1520
	11th to 20th	Day	65% 8% 9% 12% 6%	1906
	21st to end	Day	74% 3 5% 15% 3	2772
January	1st to 10th	Night	67% 7% 15% 9% 2	4429
	11th to 20th	Night	62% 7% 14% 12% 5%	4440
	21st to end	Night	68% 6% 9% 9% 7%	4788
February	1st to 10th	Night	64% 5% 9% 15% 6% 1	2470
	11th to 20th	Night	61% 5% 9% 17% 6% 1	2405
	21st to end	Night	58% 5% 10% 18% 9% 1	1903
March	1st to 10th	Night	57% 5% 12% 15% 9% 2	3715
	11th to 20th	Night	61% 6% 10% 14% 7% 1	3480
	21st to end	Night	44% 6% 10% 22% 14% 3	3608
April	1st to 10th	Night	54% 5% 11% 16% 13% 2	1900
	11th to 20th	Night	48% 5% 9% 23% 14% 2	1875
	21st to end	Night	53% 4 8% 17% 15% 2	1735
May	1st to 10th	Night	51% 9% 10% 18% 9% 2	2520
	11th to 20th	Night	45% 9% 14% 20% 10% 2	2496
	21st to end	Night	46% 8% 10% 20% 14% 2	2739
June	1st to 10th	Night	47% 8% 15% 21% 9% 1	1520
	11th to 20th	Night	42% 6% 13% 25% 12% 2	1520
	21st to end	Night	47% 8% 11% 21% 12%	1520
July	1st to 10th	Night	48% 4 17% 20% 11%	2480
	11th to 20th	Night	44% 5% 15% 29% 8%	2472
	21st to end	Night	35% 7% 15% 33% 11%	2651
August	1st to 10th	Night	44% 7% 13% 27% 9%	2525
	11th to 20th	Night	44% 5% 17% 27% 7%	2812
	21st to end	Night	44% 5% 14% 23% 11% 2	3444
September	1st to 10th	Night	38% 7% 13% 29% 12%	1900
	11th to 20th	Night	37% 6% 15% 33% 9%	1900
	21st to end	Night	44% 6% 13% 27% 9%	2156
October	1st to 10th	Night	47% 7% 11% 24% 11%	2280
	11th to 20th	Night	56% 6% 12% 19% 6% 1	2280
	21st to end	Night	58% 7% 12% 16% 6%	2667
November	1st to 10th	Night	55% 7% 13% 18% 7%	2444
	11th to 20th	Night	60% 6% 11% 15% 7% 1	2660
	21st to end	Night	67% 7% 11% 13% 2	2660
December	1st to 10th	Night	71% 5% 10% 10% 3	2660
	11th to 20th	Night	64% 5% 9% 14% 7%	3288
	21st to end	Night	73% 4 6% 13% 4	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	22% 21% 35% 18% 4 1	180
	11th to 20th	Day	30% 13% 35% 16% 6% 1	180
	21st to end	Day	21% 18% 33% 20% 7%	222
February	1st to 10th	Day	27% 26% 35% 9% 4	270
	11th to 20th	Day	26% 29% 36% 9% 1	270
	21st to end	Day	31% 20% 34% 13% 1	363
March	1st to 10th	Day	23% 20% 34% 18% 4	460
	11th to 20th	Day	26% 19% 33% 18% 4 1	460
	21st to end	Day	30% 18% 31% 15% 5% 1	506
April	1st to 10th	Day	33% 17% 27% 16% 7%	460
	11th to 20th	Day	35% 19% 21% 14% 9% 3	452
	21st to end	Day	32% 20% 28% 13% 6% 1	460
May	1st to 10th	Day	28% 14% 32% 17% 6% 3	463
	11th to 20th	Day	23% 16% 32% 19% 8% 2	487
	21st to end	Day	23% 17% 30% 21% 8% 2	529
June	1st to 10th	Day	25% 13% 33% 21% 7% 1	490
	11th to 20th	Day	18% 16% 30% 22% 12% 2	490
	21st to end	Day	20% 14% 32% 22% 10% 1	490
July	1st to 10th	Day	14% 8% 32% 34% 10% 2	485
	11th to 20th	Day	14% 10% 36% 26% 12% 2	484
	21st to end	Day	13% 8% 32% 29% 15% 2	532
August	1st to 10th	Day	17% 7% 28% 30% 15% 3	486
	11th to 20th	Day	19% 7% 26% 25% 16% 8%	479
	21st to end	Day	15% 13% 31% 21% 13% 6%	539
September	1st to 10th	Day	18% 13% 28% 22% 13% 6%	490
	11th to 20th	Day	15% 12% 24% 21% 17% 10%	490
	21st to end	Day	21% 12% 27% 19% 14% 7%	490
October	1st to 10th	Day	27% 14% 23% 21% 11% 3	490
	11th to 20th	Day	30% 21% 27% 14% 6% 1	490
	21st to end	Day	31% 14% 30% 19% 6%	454
November	1st to 10th	Day	27% 17% 28% 22% 5% 1	332
	11th to 20th	Day	29% 19% 33% 12% 5% 1	180
	21st to end	Day	32% 22% 30% 12% 2 1	180
December	1st to 10th	Day	30% 16% 35% 16% 3 1	180
	11th to 20th	Day	29% 26% 32% 9% 3 1	180
	21st to end	Day	31% 18% 31% 15% 5% 1	198
January	1st to 10th	Night	29% 14% 33% 19% 5%	760
	11th to 20th	Night	31% 14% 25% 23% 6%	760
	21st to end	Night	18% 12% 33% 28% 8% 1	836
February	1st to 10th	Night	21% 16% 36% 23% 5%	760
	11th to 20th	Night	23% 16% 36% 20% 4	743
	21st to end	Night	23% 18% 29% 25% 4	628
March	1st to 10th	Night	24% 19% 29% 25% 4	760
	11th to 20th	Night	25% 16% 30% 23% 6%	760
	21st to end	Night	21% 15% 30% 25% 8%	836
April	1st to 10th	Night	27% 16% 25% 27% 5%	760
	11th to 20th	Night	25% 17% 26% 23% 9%	751
	21st to end	Night	27% 13% 26% 24% 9% 1	595
May	1st to 10th	Night	25% 9% 32% 23% 10% 1	380
	11th to 20th	Night	22% 11% 28% 31% 9%	374
	21st to end	Night	16% 9% 36% 29% 9%	411
June	1st to 10th	Night	17% 9% 34% 34% 6% 1	380
	11th to 20th	Night	18% 9% 24% 33% 13% 1	380
	21st to end	Night	19% 6% 25% 36% 14%	380
July	1st to 10th	Night	12% 5% 25% 42% 16%	370
	11th to 20th	Night	13% 5% 21% 43% 18%	368
	21st to end	Night	11% 5% 25% 41% 17% 2	416
August	1st to 10th	Night	10% 6% 23% 39% 22% 1	394
	11th to 20th	Night	14% 3 17% 37% 26% 2	564
	21st to end	Night	16% 7% 25% 31% 19% 2	817
September	1st to 10th	Night	17% 5% 28% 31% 18% 1	760
	11th to 20th	Night	18% 6% 22% 30% 20% 4	760
	21st to end	Night	21% 9% 23% 27% 19% 1	760
October	1st to 10th	Night	25% 9% 27% 23% 14% 2	760
	11th to 20th	Night	29% 12% 28% 21% 8% 1	760
	21st to end	Night	30% 12% 28% 24% 6%	836
November	1st to 10th	Night	28% 16% 25% 24% 6% 1	743
	11th to 20th	Night	26% 16% 29% 19% 9% 1	760
	21st to end	Night	34% 14% 26% 21% 5%	760
December	1st to 10th	Night	32% 15% 28% 19% 5%	760
	11th to 20th	Night	27% 16% 30% 20% 5% 1	760
	21st to end	Night	34% 15% 27% 20% 3 1	836

Page generated at 2024-10-29 11:20:48. Version ac07

Copyright © 2024 Attilla Danko.