Woodpecker Lodge Observatory
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Woodpecker Lodge Observatory clear sky chart from 2005-11-06 to 2026-04-17.

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% 10% 3 7% 5% 4 4 3 5% 6% 33%	131454
	Night	19% 10% 3 7% 5% 4 4 3 5% 6% 34%	130860
Transparency	Day	51% 6% 12% 20% 10% 1	134946
	Night	51% 6% 12% 20% 11% 1	135455
Seeing	Day	27% 17% 31% 18% 6% 1	18317
	Night	25% 15% 33% 21% 6%	26184

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% 5% 9% 5% 4 4 4 4 5% 27%	4093
	11th to 20th	Day	14% 16% 6% 12% 7% 5% 4 3 4 4 24%	4311
	21st to end	Day	6% 9% 3 8% 6% 5% 5% 4 5% 8% 41%	5541
February	1st to 10th	Day	11% 14% 4 9% 6% 4 4 5% 5% 5% 33%	1890
	11th to 20th	Day	15% 13% 5% 7% 5% 5% 5% 4 5% 7% 30%	1843
	21st to end	Day	11% 13% 4 9% 5% 5% 4 3 5% 5% 35%	1625
March	1st to 10th	Day	22% 14% 3 8% 4 4 4 3 4 5% 29%	4874
	11th to 20th	Day	19% 14% 4 10% 5% 5% 4 3 4 4 27%	5090
	21st to end	Day	26% 14% 3 7% 4 4 3 3 5% 6% 25%	5587
April	1st to 10th	Day	21% 14% 5% 7% 4 3 3 3 5% 6% 28%	2473
	11th to 20th	Day	22% 11% 3 7% 4 4 4 3 4 5% 34%	2650
	21st to end	Day	27% 10% 3 6% 4 4 4 3 4 5% 31%	2600
May	1st to 10th	Day	25% 14% 3 7% 5% 4 4 3 4 5% 26%	5950
	11th to 20th	Day	25% 11% 3 8% 4 4 4 3 4 5% 30%	6318
	21st to end	Day	23% 9% 2 6% 5% 4 4 4 5% 7% 30%	7195
June	1st to 10th	Day	27% 9% 3 7% 5% 4 4 3 5% 6% 28%	3000
	11th to 20th	Day	21% 7% 3 5% 4 5% 5% 4 6% 7% 33%	3000
	21st to end	Day	29% 8% 2 6% 5% 4 4 3 5% 6% 27%	3000
July	1st to 10th	Day	16% 7% 3 8% 6% 5% 6% 5% 7% 9% 29%	6820
	11th to 20th	Day	15% 5% 2 7% 4 5% 5% 4 6% 7% 40%	6820
	21st to end	Day	13% 6% 2 6% 5% 5% 5% 4 6% 8% 39%	6844
August	1st to 10th	Day	18% 7% 2 7% 5% 5% 6% 4 6% 7% 34%	4235
	11th to 20th	Day	14% 6% 3 8% 5% 5% 6% 4 6% 8% 33%	4175
	21st to end	Day	16% 5% 2 5% 4 4 4 3 5% 8% 43%	4675
September	1st to 10th	Day	15% 5% 2 6% 5% 4 5% 4 5% 7% 41%	2400
	11th to 20th	Day	18% 6% 2 5% 3 3 4 3 4 5% 45%	2218
	21st to end	Day	20% 6% 2 6% 4 4 4 3 5% 7% 40%	2200
October	1st to 10th	Day	16% 7% 2 6% 5% 4 4 3 4 7% 42%	2005
	11th to 20th	Day	21% 9% 2 6% 4 4 3 3 5% 6% 37%	2000
	21st to end	Day	23% 10% 3 7% 5% 4 4 4 4 5% 31%	2085
November	1st to 10th	Day	20% 9% 2 7% 4 5% 4 3 5% 7% 33%	1709
	11th to 20th	Day	21% 10% 3 7% 5% 4 4 3 5% 6% 32%	1680
	21st to end	Day	20% 12% 4 7% 5% 4 5% 3 4 5% 31%	1680
December	1st to 10th	Day	18% 12% 4 8% 4 4 4 3 5% 5% 35%	2627
	11th to 20th	Day	20% 11% 3 9% 4 4 4 3 4 5% 33%	2688
	21st to end	Day	17% 13% 5% 9% 3 4 4 2 4 3 36%	3553
January	1st to 10th	Night	13% 17% 4 8% 5% 4 4 3 5% 7% 30%	8831
	11th to 20th	Night	18% 15% 5% 10% 6% 4 4 3 4 5% 25%	8578
	21st to end	Night	7% 10% 4 7% 4 5% 5% 4 6% 7% 42%	8625
February	1st to 10th	Night	14% 12% 4 8% 5% 4 5% 5% 6% 4 33%	2730
	11th to 20th	Night	16% 13% 5% 8% 6% 5% 5% 3 3 6% 31%	2663
	21st to end	Night	13% 15% 4 6% 5% 4 4 4 5% 4 35%	2176
March	1st to 10th	Night	25% 13% 3 8% 5% 5% 5% 3 3 3 27%	5185
	11th to 20th	Night	22% 13% 3 9% 5% 4 4 4 5% 6% 24%	5089
	21st to end	Night	30% 12% 3 6% 4 3 3 2 5% 4 27%	5587
April	1st to 10th	Night	25% 12% 3 8% 4 4 3 3 4 5% 29%	2144
	11th to 20th	Night	24% 9% 3 6% 4 3 4 3 5% 5% 34%	1833
	21st to end	Night	24% 12% 2 6% 4 4 3 3 4 4 33%	1800
May	1st to 10th	Night	24% 13% 3 7% 4 4 3 3 4 6% 28%	3993
	11th to 20th	Night	26% 7% 2 7% 4 4 4 3 5% 6% 32%	3596
	21st to end	Night	19% 8% 3 7% 5% 5% 4 4 6% 7% 34%	3730
June	1st to 10th	Night	28% 8% 2 6% 4 3 4 3 5% 6% 32%	1400
	11th to 20th	Night	18% 7% 2 7% 5% 4 4 4 4 7% 37%	1400
	21st to end	Night	29% 8% 3 6% 5% 3 4 4 4 5% 29%	1400
July	1st to 10th	Night	19% 7% 2 7% 4 4 5% 5% 6% 7% 33%	3160
	11th to 20th	Night	15% 6% 2 7% 5% 5% 5% 4 6% 7% 38%	3160
	21st to end	Night	12% 6% 2 6% 5% 5% 5% 4 6% 8% 44%	3966
August	1st to 10th	Night	17% 6% 2 8% 5% 6% 6% 5% 7% 7% 32%	2915
	11th to 20th	Night	12% 8% 3 7% 4 5% 4 5% 6% 8% 38%	2872
	21st to end	Night	15% 4 2 6% 4 3 4 4 5% 7% 46%	3223
September	1st to 10th	Night	17% 6% 2 5% 3 3 4 3 4 6% 47%	2000
	11th to 20th	Night	16% 6% 2 4 3 4 3 3 4 6% 49%	2179
	21st to end	Night	19% 7% 2 4 4 3 4 3 5% 5% 45%	2200
October	1st to 10th	Night	19% 6% 2 6% 3 3 4 3 4 6% 44%	2395
	11th to 20th	Night	19% 8% 3 7% 5% 4 4 3 4 6% 38%	2400
	21st to end	Night	23% 10% 2 6% 4 4 3 3 4 5% 37%	2753
November	1st to 10th	Night	21% 11% 3 7% 4 4 4 3 4 5% 35%	2808
	11th to 20th	Night	21% 11% 2 8% 4 4 4 3 6% 5% 30%	2940
	21st to end	Night	23% 11% 3 7% 5% 4 4 3 4 5% 31%	2940
December	1st to 10th	Night	15% 10% 4 8% 4 4 4 3 5% 6% 38%	4781
	11th to 20th	Night	22% 10% 3 7% 4 4 3 3 4 5% 35%	5741
	21st to end	Night	20% 12% 4 9% 4 4 3 3 4 5% 32%	7667

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	60% 5% 10% 13% 12%	4094
	11th to 20th	Day	62% 5% 11% 12% 9% 1	4338
	21st to end	Day	41% 5% 12% 21% 19% 1	5541
February	1st to 10th	Day	51% 6% 9% 19% 12% 2	1890
	11th to 20th	Day	53% 5% 11% 19% 10% 1	1851
	21st to end	Day	50% 6% 9% 22% 12% 2	1625
March	1st to 10th	Day	57% 6% 9% 13% 11% 3	4878
	11th to 20th	Day	60% 6% 12% 14% 6% 2	5090
	21st to end	Day	61% 3 6% 18% 11% 2	5587
April	1st to 10th	Day	58% 4 8% 16% 12% 2	2473
	11th to 20th	Day	53% 5% 9% 20% 11% 2	2650
	21st to end	Day	56% 5% 9% 14% 12% 4	2600
May	1st to 10th	Day	61% 5% 9% 15% 10%	5961
	11th to 20th	Day	54% 7% 13% 18% 5% 1	6322
	21st to end	Day	50% 8% 11% 19% 11%	7195
June	1st to 10th	Day	56% 7% 11% 17% 9% 1	3000
	11th to 20th	Day	49% 7% 12% 20% 11% 2	3000
	21st to end	Day	58% 6% 11% 15% 10% 1	3000
July	1st to 10th	Day	50% 6% 17% 19% 8%	6745
	11th to 20th	Day	42% 6% 15% 28% 8%	6739
	21st to end	Day	42% 7% 16% 28% 7%	6648
August	1st to 10th	Day	48% 7% 15% 22% 9%	4222
	11th to 20th	Day	46% 9% 15% 23% 7%	4214
	21st to end	Day	39% 6% 14% 24% 17%	4675
September	1st to 10th	Day	40% 8% 14% 25% 13%	2400
	11th to 20th	Day	40% 5% 12% 27% 14% 1	2218
	21st to end	Day	42% 7% 10% 26% 14% 1	2200
October	1st to 10th	Day	43% 5% 16% 26% 9%	3265
	11th to 20th	Day	47% 5% 11% 27% 9%	3240
	21st to end	Day	45% 5% 15% 20% 15%	3348
November	1st to 10th	Day	51% 6% 11% 22% 9% 1	1709
	11th to 20th	Day	53% 5% 13% 16% 11% 1	1680
	21st to end	Day	55% 6% 13% 18% 7%	1680
December	1st to 10th	Day	52% 4 14% 20% 9%	2627
	11th to 20th	Day	55% 4 11% 18% 10% 2	2688
	21st to end	Day	54% 4 10% 16% 13% 3	3553
January	1st to 10th	Night	54% 4 13% 21% 7%	8831
	11th to 20th	Night	61% 5% 10% 16% 8% 1	8625
	21st to end	Night	40% 5% 11% 23% 18% 2	8625
February	1st to 10th	Night	52% 6% 11% 16% 12% 2	2730
	11th to 20th	Night	56% 5% 9% 17% 11% 1	2666
	21st to end	Night	50% 6% 8% 19% 14% 2	2176
March	1st to 10th	Night	61% 4 8% 11% 13% 3	5194
	11th to 20th	Night	58% 7% 13% 12% 8% 1	5090
	21st to end	Night	61% 3 5% 17% 13% 2	5587
April	1st to 10th	Night	58% 4 8% 16% 10% 4	2144
	11th to 20th	Night	51% 5% 10% 18% 14% 2	1833
	21st to end	Night	54% 5% 10% 15% 13% 3	1800
May	1st to 10th	Night	56% 6% 10% 15% 11% 1	3999
	11th to 20th	Night	51% 7% 13% 19% 8% 2	3597
	21st to end	Night	46% 11% 15% 18% 10%	3731
June	1st to 10th	Night	54% 7% 10% 20% 10% 1	1400
	11th to 20th	Night	48% 6% 12% 23% 9% 2	1400
	21st to end	Night	57% 6% 11% 17% 8% 1	1400
July	1st to 10th	Night	50% 6% 16% 18% 9%	3125
	11th to 20th	Night	44% 6% 16% 29% 4	3118
	21st to end	Night	38% 8% 17% 27% 10%	3848
August	1st to 10th	Night	50% 8% 13% 20% 8%	2903
	11th to 20th	Night	42% 9% 19% 24% 6%	2899
	21st to end	Night	38% 6% 16% 25% 14% 1	3223
September	1st to 10th	Night	38% 7% 12% 30% 13% 1	2000
	11th to 20th	Night	38% 6% 13% 29% 14% 1	2179
	21st to end	Night	40% 6% 12% 27% 14% 1	2200
October	1st to 10th	Night	46% 4 14% 25% 10% 1	3915
	11th to 20th	Night	45% 4 11% 30% 10%	3899
	21st to end	Night	43% 5% 18% 21% 13%	4440
November	1st to 10th	Night	52% 5% 12% 20% 9% 1	2808
	11th to 20th	Night	54% 6% 13% 17% 9% 1	2940
	21st to end	Night	56% 6% 13% 16% 9%	2940
December	1st to 10th	Night	48% 4 12% 26% 9%	4781
	11th to 20th	Night	52% 4 9% 21% 13% 1	5742
	21st to end	Night	55% 5% 9% 18% 12% 1	7667

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	30% 21% 31% 15% 2	220
	11th to 20th	Day	40% 17% 25% 11% 5% 1	220
	21st to end	Day	23% 19% 33% 18% 5% 1	389
February	1st to 10th	Day	26% 19% 30% 17% 6% 2	430
	11th to 20th	Day	27% 23% 32% 12% 5% 1	426
	21st to end	Day	24% 23% 33% 16% 3	391
March	1st to 10th	Day	34% 21% 29% 13% 2 1	540
	11th to 20th	Day	31% 22% 28% 15% 4 1	540
	21st to end	Day	33% 20% 30% 13% 3 1	594
April	1st to 10th	Day	36% 25% 26% 10% 3	540
	11th to 20th	Day	33% 22% 25% 15% 4 1	516
	21st to end	Day	36% 19% 26% 13% 5% 1	500
May	1st to 10th	Day	37% 19% 25% 14% 4 1	528
	11th to 20th	Day	31% 15% 29% 16% 7% 1	724
	21st to end	Day	29% 18% 33% 16% 5%	790
June	1st to 10th	Day	33% 16% 28% 16% 6% 1	730
	11th to 20th	Day	24% 18% 30% 21% 6% 1	730
	21st to end	Day	30% 14% 30% 20% 5%	730
July	1st to 10th	Day	22% 13% 36% 22% 7%	720
	11th to 20th	Day	16% 11% 40% 24% 8% 1	718
	21st to end	Day	18% 14% 34% 26% 7% 1	678
August	1st to 10th	Day	15% 12% 36% 27% 8% 2	526
	11th to 20th	Day	19% 10% 28% 30% 11% 1	519
	21st to end	Day	19% 13% 31% 23% 11% 3	583
September	1st to 10th	Day	18% 15% 35% 21% 9% 2	530
	11th to 20th	Day	22% 12% 33% 22% 9% 3	530
	21st to end	Day	21% 15% 35% 17% 8% 5%	530
October	1st to 10th	Day	19% 16% 28% 22% 12% 3	423
	11th to 20th	Day	29% 18% 25% 18% 9% 2	420
	21st to end	Day	32% 20% 29% 13% 5% 1	462
November	1st to 10th	Day	33% 16% 32% 14% 3 1	425
	11th to 20th	Day	32% 20% 27% 15% 6% 1	430
	21st to end	Day	32% 21% 28% 14% 3 1	430
December	1st to 10th	Day	30% 18% 28% 18% 5%	393
	11th to 20th	Day	35% 25% 30% 8% 2	220
	21st to end	Day	30% 20% 32% 13% 5%	242
January	1st to 10th	Night	24% 19% 34% 19% 4	950
	11th to 20th	Night	26% 19% 32% 19% 5%	904
	21st to end	Night	19% 20% 38% 19% 4	924
February	1st to 10th	Night	22% 19% 35% 19% 5% 1	840
	11th to 20th	Night	26% 19% 34% 17% 3	823
	21st to end	Night	23% 16% 37% 20% 4	692
March	1st to 10th	Night	27% 17% 35% 19% 1	840
	11th to 20th	Night	26% 17% 33% 19% 4	840
	21st to end	Night	24% 17% 36% 18% 5%	924
April	1st to 10th	Night	32% 19% 30% 17% 2	705
	11th to 20th	Night	29% 14% 35% 18% 5%	613
	21st to end	Night	33% 16% 28% 19% 4	600
May	1st to 10th	Night	30% 14% 30% 23% 4	600
	11th to 20th	Night	27% 13% 34% 22% 5%	592
	21st to end	Night	19% 17% 39% 21% 4	561
June	1st to 10th	Night	31% 8% 32% 25% 6%	400
	11th to 20th	Night	22% 12% 32% 27% 7%	400
	21st to end	Night	33% 7% 30% 26% 5%	400
July	1st to 10th	Night	19% 9% 42% 23% 7%	390
	11th to 20th	Night	16% 7% 34% 33% 10%	388
	21st to end	Night	18% 9% 33% 31% 9%	550
August	1st to 10th	Night	17% 6% 34% 30% 12% 1	598
	11th to 20th	Night	17% 5% 32% 33% 11% 1	592
	21st to end	Night	16% 8% 28% 32% 14% 1	660
September	1st to 10th	Night	18% 11% 36% 27% 8%	600
	11th to 20th	Night	20% 9% 30% 28% 12% 1	779
	21st to end	Night	23% 10% 33% 24% 9%	800
October	1st to 10th	Night	22% 11% 34% 24% 10%	800
	11th to 20th	Night	22% 12% 34% 23% 9%	800
	21st to end	Night	28% 17% 33% 18% 4	880
November	1st to 10th	Night	29% 15% 31% 19% 5%	894
	11th to 20th	Night	31% 16% 29% 16% 6% 1	950
	21st to end	Night	29% 19% 27% 20% 4 1	950
December	1st to 10th	Night	29% 16% 34% 17% 4	950
	11th to 20th	Night	28% 21% 32% 15% 3	950
	21st to end	Night	29% 19% 29% 17% 5% 1	1045

Page generated at 2026-04-14 03:44:23. Version ac07

Copyright © 2026 Attilla Danko.