Wonder Lake State Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Wonder Lake State Park clear sky chart from 2005-11-06 to 2024-04-03.

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% 7% 3 5% 5% 3 5% 5% 5% 7% 39%	78739
	Night	17% 7% 3 5% 5% 3 4 4 5% 7% 40%	81385
Transparency	Day	44% 6% 11% 23% 14% 2	78444
	Night	44% 5% 11% 23% 15% 2	81214
Seeing	Day	25% 16% 29% 19% 9% 3	14115
	Night	23% 14% 28% 26% 8% 1	23362

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% 7% 2 6% 5% 3 4 4 4 6% 45%	2517
	11th to 20th	Day	15% 10% 3 7% 8% 3 5% 4 4 5% 35%	2520
	21st to end	Day	21% 12% 6% 7% 5% 3 3 3 4 5% 31%	2932
February	1st to 10th	Day	17% 8% 3 6% 5% 3 6% 5% 5% 7% 35%	1725
	11th to 20th	Day	14% 8% 3 5% 5% 4 4 5% 5% 7% 40%	1848
	21st to end	Day	19% 9% 4 6% 4 3 5% 3 5% 6% 37%	1570
March	1st to 10th	Day	16% 7% 2 7% 6% 3 4 4 5% 6% 40%	1897
	11th to 20th	Day	15% 7% 3 6% 6% 3 5% 5% 5% 7% 37%	1971
	21st to end	Day	19% 9% 3 6% 4 3 4 3 4 5% 39%	2507
April	1st to 10th	Day	18% 9% 3 6% 5% 2 5% 4 5% 5% 37%	2184
	11th to 20th	Day	17% 6% 3 5% 5% 3 5% 5% 4 8% 40%	2134
	21st to end	Day	21% 6% 3 5% 5% 3 4 4 5% 6% 39%	2218
May	1st to 10th	Day	23% 8% 3 5% 5% 3 4 4 6% 6% 33%	2340
	11th to 20th	Day	19% 6% 2 4 5% 3 5% 5% 5% 7% 39%	2459
	21st to end	Day	15% 6% 3 5% 5% 3 5% 5% 6% 8% 41%	2725
June	1st to 10th	Day	18% 5% 2 5% 5% 3 5% 6% 8% 8% 35%	2520
	11th to 20th	Day	16% 6% 3 6% 6% 3 6% 5% 6% 8% 35%	2520
	21st to end	Day	13% 6% 2 6% 6% 4 5% 6% 5% 8% 38%	2520
July	1st to 10th	Day	13% 6% 3 5% 5% 4 5% 6% 6% 8% 40%	2520
	11th to 20th	Day	11% 5% 3 5% 6% 3 6% 5% 7% 10% 40%	2520
	21st to end	Day	12% 6% 3 6% 5% 4 6% 6% 6% 9% 37%	2744
August	1st to 10th	Day	11% 7% 3 5% 6% 4 5% 6% 8% 8% 37%	2424
	11th to 20th	Day	12% 7% 2 5% 5% 4 5% 7% 6% 9% 38%	2126
	21st to end	Day	13% 6% 3 5% 5% 3 5% 5% 6% 8% 42%	2376
September	1st to 10th	Day	14% 6% 2 6% 5% 3 6% 5% 5% 6% 42%	2160
	11th to 20th	Day	13% 5% 3 5% 4 3 3 4 4 7% 49%	2067
	21st to end	Day	15% 7% 2 6% 5% 3 4 5% 4 8% 41%	1980
October	1st to 10th	Day	23% 7% 2 5% 4 3 4 4 4 4 41%	1901
	11th to 20th	Day	15% 7% 2 4 4 3 4 4 6% 7% 44%	1800
	21st to end	Day	22% 6% 2 4 5% 3 5% 5% 5% 6% 37%	1805
November	1st to 10th	Day	14% 7% 2 4 4 3 4 3 4 6% 50%	1671
	11th to 20th	Day	18% 6% 4 4 5% 2 3 3 5% 7% 45%	1710
	21st to end	Day	17% 6% 3 5% 4 2 5% 4 6% 6% 43%	1630
December	1st to 10th	Day	19% 8% 4 7% 5% 4 4 4 4 6% 35%	1520
	11th to 20th	Day	21% 6% 2 4 3 2 3 4 4 7% 42%	1906
	21st to end	Day	19% 10% 4 7% 7% 3 4 4 4 7% 30%	2772
January	1st to 10th	Night	16% 7% 2 4 4 2 4 4 5% 7% 44%	4429
	11th to 20th	Night	15% 9% 4 7% 6% 2 4 5% 5% 6% 39%	4440
	21st to end	Night	23% 11% 4 7% 5% 3 3 3 4 5% 32%	4724
February	1st to 10th	Night	16% 9% 4 5% 5% 3 5% 4 5% 6% 40%	2453
	11th to 20th	Night	15% 8% 3 6% 4 3 5% 5% 6% 7% 39%	2218
	21st to end	Night	19% 6% 3 6% 5% 3 4 4 5% 5% 40%	1884
March	1st to 10th	Night	17% 7% 2 5% 4 3 4 5% 6% 7% 41%	2270
	11th to 20th	Night	16% 7% 3 5% 6% 3 4 5% 5% 7% 40%	2204
	21st to end	Night	17% 8% 3 5% 4 2 4 5% 4 6% 40%	2090
April	1st to 10th	Night	16% 9% 3 5% 5% 4 5% 5% 5% 6% 36%	1821
	11th to 20th	Night	18% 7% 3 6% 5% 3 5% 4 5% 6% 38%	1775
	21st to end	Night	21% 8% 2 6% 4 2 4 3 5% 6% 39%	1740
May	1st to 10th	Night	21% 8% 4 6% 6% 3 4 4 5% 7% 32%	1620
	11th to 20th	Night	19% 8% 3 5% 4 3 4 4 5% 6% 39%	1449
	21st to end	Night	15% 8% 3 5% 4 3 4 4 5% 8% 41%	1550
June	1st to 10th	Night	18% 5% 2 5% 5% 3 5% 4 5% 7% 41%	1440
	11th to 20th	Night	15% 6% 3 6% 4 2 5% 5% 7% 9% 39%	1440
	21st to end	Night	12% 4 2 5% 5% 2 5% 5% 6% 11% 42%	1440
July	1st to 10th	Night	13% 6% 3 5% 4 4 4 6% 6% 8% 41%	1440
	11th to 20th	Night	13% 5% 3 6% 5% 3 4 6% 6% 10% 39%	1440
	21st to end	Night	10% 5% 3 6% 5% 3 6% 6% 6% 9% 42%	1574
August	1st to 10th	Night	8% 6% 2 5% 6% 3 6% 5% 7% 9% 43%	1494
	11th to 20th	Night	12% 6% 3 6% 7% 4 6% 5% 5% 9% 36%	1774
	21st to end	Night	16% 6% 2 5% 4 2 3 4 5% 7% 45%	1980
September	1st to 10th	Night	16% 6% 2 6% 5% 3 4 4 4 6% 45%	1800
	11th to 20th	Night	14% 5% 2 4 3 2 3 3 4 7% 53%	1891
	21st to end	Night	17% 6% 3 5% 4 2 4 5% 4 5% 46%	1980
October	1st to 10th	Night	20% 7% 3 5% 4 3 3 4 4 5% 42%	2056
	11th to 20th	Night	16% 5% 3 5% 4 3 4 3 5% 7% 45%	2160
	21st to end	Night	22% 6% 3 5% 4 3 4 4 5% 6% 38%	2551
November	1st to 10th	Night	13% 6% 2 5% 5% 2 5% 3 5% 6% 47%	2407
	11th to 20th	Night	19% 6% 3 4 4 2 3 4 4 7% 44%	2470
	21st to end	Night	15% 6% 2 5% 5% 3 4 4 6% 8% 43%	2549
December	1st to 10th	Night	19% 8% 2 6% 5% 3 5% 4 5% 6% 38%	2660
	11th to 20th	Night	19% 8% 3 5% 4 3 4 5% 4 7% 38%	3288
	21st to end	Night	21% 11% 3 6% 5% 2 4 3 5% 6% 33%	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	41% 4 10% 33% 9% 2	2518
	11th to 20th	Day	50% 6% 9% 24% 10% 1	2520
	21st to end	Day	56% 4 8% 21% 10% 1	2932
February	1st to 10th	Day	48% 6% 11% 20% 13% 1	1725
	11th to 20th	Day	43% 6% 10% 23% 16% 2	1857
	21st to end	Day	49% 4 11% 21% 12% 3	1570
March	1st to 10th	Day	45% 4 11% 22% 14% 3	1900
	11th to 20th	Day	44% 6% 10% 24% 14% 2	1971
	21st to end	Day	48% 4 7% 17% 18% 5%	2507
April	1st to 10th	Day	47% 6% 8% 21% 14% 4	2184
	11th to 20th	Day	43% 5% 10% 23% 16% 3	2134
	21st to end	Day	45% 6% 10% 21% 15% 4	2218
May	1st to 10th	Day	51% 5% 9% 20% 13% 2	2340
	11th to 20th	Day	44% 6% 10% 21% 16% 2	2463
	21st to end	Day	41% 7% 16% 22% 13% 2	2725
June	1st to 10th	Day	43% 8% 13% 22% 12% 1	2520
	11th to 20th	Day	45% 7% 13% 23% 11% 1	2520
	21st to end	Day	42% 8% 12% 25% 12% 1	2520
July	1st to 10th	Day	41% 8% 12% 21% 16% 2	2450
	11th to 20th	Day	38% 7% 15% 25% 14% 1	2445
	21st to end	Day	41% 7% 12% 20% 16% 2	2591
August	1st to 10th	Day	41% 7% 14% 25% 13%	2410
	11th to 20th	Day	40% 7% 17% 23% 12% 1	2126
	21st to end	Day	38% 6% 11% 25% 18% 1	2376
September	1st to 10th	Day	41% 7% 11% 23% 17% 1	2160
	11th to 20th	Day	36% 4 10% 24% 25% 2	2067
	21st to end	Day	42% 5% 11% 22% 17% 3	1980
October	1st to 10th	Day	47% 4 9% 23% 15% 3	1901
	11th to 20th	Day	38% 5% 13% 27% 15% 2	1800
	21st to end	Day	47% 5% 10% 21% 15% 3	1805
November	1st to 10th	Day	37% 4 12% 27% 18% 3	1671
	11th to 20th	Day	40% 4 11% 23% 18% 3	1710
	21st to end	Day	41% 4 14% 28% 12% 2	1630
December	1st to 10th	Day	50% 5% 13% 18% 14% 1	1520
	11th to 20th	Day	42% 5% 15% 21% 13% 2	1906
	21st to end	Day	54% 6% 10% 21% 9%	2772
January	1st to 10th	Night	40% 5% 11% 29% 11% 3	4429
	11th to 20th	Night	45% 5% 13% 23% 11% 3	4440
	21st to end	Night	55% 4 8% 21% 11% 2	4724
February	1st to 10th	Night	46% 5% 12% 23% 12% 2	2453
	11th to 20th	Night	44% 5% 10% 18% 19% 4	2220
	21st to end	Night	45% 4 8% 23% 15% 4	1884
March	1st to 10th	Night	41% 6% 11% 23% 15% 3	2280
	11th to 20th	Night	44% 5% 9% 22% 16% 3	2205
	21st to end	Night	45% 5% 8% 19% 19% 5%	2090
April	1st to 10th	Night	47% 6% 10% 19% 15% 3	1821
	11th to 20th	Night	46% 5% 10% 19% 18% 1	1775
	21st to end	Night	46% 5% 8% 22% 15% 4	1740
May	1st to 10th	Night	52% 6% 9% 17% 14% 2	1620
	11th to 20th	Night	46% 5% 10% 20% 17% 2	1450
	21st to end	Night	42% 7% 15% 22% 12% 2	1551
June	1st to 10th	Night	43% 7% 10% 24% 15% 2	1440
	11th to 20th	Night	41% 6% 18% 24% 10% 1	1440
	21st to end	Night	35% 8% 15% 27% 14% 1	1440
July	1st to 10th	Night	39% 8% 14% 23% 14% 2	1400
	11th to 20th	Night	39% 7% 15% 28% 10% 1	1392
	21st to end	Night	37% 7% 17% 21% 16% 2	1486
August	1st to 10th	Night	35% 9% 16% 26% 14% 1	1484
	11th to 20th	Night	44% 7% 15% 22% 10% 1	1774
	21st to end	Night	38% 6% 12% 23% 20% 1	1980
September	1st to 10th	Night	41% 5% 10% 28% 16% 1	1800
	11th to 20th	Night	33% 4 11% 25% 25% 2	1891
	21st to end	Night	41% 5% 8% 22% 23% 2	1980
October	1st to 10th	Night	45% 5% 10% 24% 14% 2	2056
	11th to 20th	Night	39% 5% 12% 30% 13% 1	2160
	21st to end	Night	47% 5% 11% 21% 14% 1	2551
November	1st to 10th	Night	37% 5% 11% 22% 21% 4	2407
	11th to 20th	Night	42% 3 10% 23% 19% 4	2470
	21st to end	Night	39% 5% 13% 30% 12% 1	2549
December	1st to 10th	Night	47% 6% 11% 22% 14% 1	2660
	11th to 20th	Night	45% 6% 13% 19% 15% 2	3288
	21st to end	Night	51% 6% 11% 21% 11%	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	35% 22% 24% 16% 3	180
	11th to 20th	Day	38% 22% 26% 12% 2	180
	21st to end	Day	23% 30% 32% 10% 4 1	243
February	1st to 10th	Day	36% 27% 27% 8% 2	285
	11th to 20th	Day	31% 26% 31% 11% 1	456
	21st to end	Day	35% 21% 29% 12% 3	382
March	1st to 10th	Day	31% 20% 32% 14% 3	460
	11th to 20th	Day	31% 25% 28% 13% 3 1	460
	21st to end	Day	34% 21% 30% 10% 4 2	506
April	1st to 10th	Day	34% 22% 25% 11% 7% 1	428
	11th to 20th	Day	27% 23% 28% 12% 7% 2	412
	21st to end	Day	34% 15% 33% 13% 4 2	420
May	1st to 10th	Day	36% 18% 26% 12% 5% 3	423
	11th to 20th	Day	26% 17% 33% 18% 6% 1	447
	21st to end	Day	21% 11% 26% 27% 12% 3	485
June	1st to 10th	Day	21% 11% 32% 23% 12% 1	450
	11th to 20th	Day	18% 14% 33% 22% 12% 2	450
	21st to end	Day	16% 12% 30% 25% 15% 2	450
July	1st to 10th	Day	17% 7% 29% 28% 15% 4	445
	11th to 20th	Day	14% 6% 30% 31% 16% 3	444
	21st to end	Day	14% 8% 33% 30% 13% 2	488
August	1st to 10th	Day	15% 7% 26% 31% 16% 5%	446
	11th to 20th	Day	16% 7% 27% 28% 16% 6%	439
	21st to end	Day	13% 11% 28% 26% 14% 7%	495
September	1st to 10th	Day	19% 13% 24% 20% 18% 7%	450
	11th to 20th	Day	15% 9% 30% 24% 12% 9%	450
	21st to end	Day	22% 12% 29% 20% 11% 5%	450
October	1st to 10th	Day	30% 10% 25% 17% 15% 4	450
	11th to 20th	Day	19% 20% 28% 22% 9% 2	450
	21st to end	Day	31% 13% 27% 19% 9% 1	408
November	1st to 10th	Day	21% 17% 25% 23% 11% 2	365
	11th to 20th	Day	29% 22% 27% 15% 6% 1	370
	21st to end	Day	24% 22% 28% 19% 6% 1	290
December	1st to 10th	Day	28% 27% 29% 12% 3 1	180
	11th to 20th	Day	39% 22% 28% 9% 2	180
	21st to end	Day	30% 25% 27% 13% 6%	198
January	1st to 10th	Night	23% 19% 36% 19% 3	760
	11th to 20th	Night	28% 20% 28% 21% 3	760
	21st to end	Night	23% 22% 31% 20% 3	836
February	1st to 10th	Night	26% 19% 32% 22% 2	760
	11th to 20th	Night	25% 22% 36% 16% 1	743
	21st to end	Night	30% 20% 30% 18% 3	628
March	1st to 10th	Night	27% 20% 31% 18% 4	760
	11th to 20th	Night	25% 23% 30% 19% 3	760
	21st to end	Night	25% 21% 31% 19% 4	836
April	1st to 10th	Night	27% 20% 31% 18% 4	729
	11th to 20th	Night	23% 17% 31% 23% 5%	711
	21st to end	Night	27% 19% 30% 19% 5%	660
May	1st to 10th	Night	27% 15% 31% 22% 5% 1	540
	11th to 20th	Night	25% 14% 32% 24% 5%	388
	21st to end	Night	20% 6% 25% 37% 11% 1	389
June	1st to 10th	Night	20% 7% 28% 32% 13%	360
	11th to 20th	Night	19% 8% 24% 34% 15% 1	360
	21st to end	Night	14% 4 25% 46% 12% 1	360
July	1st to 10th	Night	16% 5% 19% 38% 21% 1	350
	11th to 20th	Night	14% 3 22% 44% 16% 1	348
	21st to end	Night	12% 4 24% 42% 17% 1	394
August	1st to 10th	Night	10% 3 27% 42% 16% 2	420
	11th to 20th	Night	15% 4 18% 39% 22% 2	710
	21st to end	Night	19% 4 18% 36% 21% 2	792
September	1st to 10th	Night	18% 6% 26% 34% 14% 3	720
	11th to 20th	Night	17% 7% 25% 30% 17% 4	720
	21st to end	Night	21% 7% 26% 29% 15% 2	720
October	1st to 10th	Night	26% 10% 22% 27% 14% 2	720
	11th to 20th	Night	19% 13% 29% 28% 10% 1	720
	21st to end	Night	28% 14% 26% 24% 8%	792
November	1st to 10th	Night	18% 14% 29% 27% 10% 1	740
	11th to 20th	Night	23% 18% 28% 22% 7% 1	760
	21st to end	Night	23% 17% 28% 25% 7% 1	760
December	1st to 10th	Night	27% 18% 29% 20% 5%	760
	11th to 20th	Night	26% 19% 29% 22% 4	760
	21st to end	Night	28% 18% 31% 22% 2	836

Page generated at 2024-03-31 06:08:52. Version ac07

Copyright © 2024 Attilla Danko.