Bonnechere Provincial Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Bonnechere Provincial Park 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	16% 10% 4 9% 5% 5% 4 4 5% 6% 32%	101645
	Night	16% 12% 4 9% 5% 5% 4 3 5% 6% 31%	97497
Transparency	Day	51% 6% 11% 21% 10% 1	105193
	Night	53% 7% 12% 19% 9% 1	102038
Seeing	Day	22% 16% 31% 19% 9% 3	14381
	Night	22% 14% 30% 24% 9% 1	23552

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% 16% 7% 14% 8% 5% 4 3 4 3 22%	2517
	11th to 20th	Day	12% 12% 6% 19% 9% 6% 4 3 4 7% 19%	2520
	21st to end	Day	15% 22% 8% 14% 6% 5% 4 3 3 3 18%	3031
February	1st to 10th	Day	10% 15% 6% 15% 9% 5% 5% 4 5% 4 21%	1710
	11th to 20th	Day	11% 17% 6% 12% 6% 6% 4 4 6% 5% 24%	1663
	21st to end	Day	17% 15% 4 9% 6% 5% 5% 5% 5% 5% 24%	1490
March	1st to 10th	Day	18% 17% 4 9% 5% 4 3 3 4 5% 27%	3276
	11th to 20th	Day	11% 17% 7% 11% 6% 5% 4 4 4 5% 26%	3480
	21st to end	Day	11% 8% 4 8% 6% 5% 4 3 4 6% 43%	3906
April	1st to 10th	Day	20% 14% 3 7% 5% 5% 4 4 4 5% 29%	2280
	11th to 20th	Day	22% 9% 3 6% 5% 4 3 3 4 5% 35%	2259
	21st to end	Day	21% 10% 3 7% 5% 4 4 3 5% 5% 33%	2470
May	1st to 10th	Day	19% 9% 3 7% 5% 4 4 3 5% 6% 33%	4384
	11th to 20th	Day	16% 9% 3 8% 4 4 4 4 4 7% 37%	4398
	21st to end	Day	16% 8% 2 7% 5% 5% 4 4 5% 7% 39%	4837
June	1st to 10th	Day	20% 9% 3 7% 5% 4 5% 4 5% 7% 30%	2660
	11th to 20th	Day	15% 6% 2 7% 5% 4 4 5% 6% 8% 39%	2660
	21st to end	Day	16% 7% 3 6% 5% 5% 5% 4 6% 8% 34%	2660
July	1st to 10th	Day	13% 7% 2 8% 5% 5% 6% 4 7% 9% 35%	4440
	11th to 20th	Day	12% 5% 2 6% 5% 5% 4 5% 7% 8% 40%	4440
	21st to end	Day	10% 5% 2 6% 4 4 5% 4 6% 8% 46%	4814
August	1st to 10th	Day	14% 6% 2 9% 6% 6% 5% 4 6% 7% 34%	4180
	11th to 20th	Day	16% 6% 2 6% 5% 5% 4 4 6% 8% 37%	4044
	21st to end	Day	10% 5% 2 6% 5% 6% 6% 4 6% 10% 41%	4276
September	1st to 10th	Day	15% 6% 3 6% 4 4 5% 3 6% 8% 41%	2280
	11th to 20th	Day	13% 6% 3 7% 5% 3 4 4 4 6% 46%	2280
	21st to end	Day	19% 7% 3 8% 5% 4 5% 3 4 7% 36%	1990
October	1st to 10th	Day	20% 9% 3 7% 5% 5% 4 3 5% 5% 35%	1900
	11th to 20th	Day	22% 12% 4 9% 5% 5% 4 3 4 5% 26%	1900
	21st to end	Day	25% 13% 4 10% 5% 5% 4 3 4 5% 22%	2014
November	1st to 10th	Day	15% 12% 5% 8% 5% 4 4 2 5% 7% 33%	1648
	11th to 20th	Day	16% 15% 5% 9% 6% 4 5% 3 5% 6% 25%	1520
	21st to end	Day	21% 17% 7% 11% 7% 5% 4 3 4 4 17%	1520
December	1st to 10th	Day	19% 21% 6% 12% 8% 5% 3 3 3 4 16%	1520
	11th to 20th	Day	18% 19% 5% 10% 6% 4 5% 3 5% 4 21%	1906
	21st to end	Day	24% 21% 6% 14% 4 3 2 2 2 4 17%	2772
January	1st to 10th	Night	15% 19% 8% 13% 8% 5% 5% 3 4 4 16%	4429
	11th to 20th	Night	11% 13% 5% 17% 8% 7% 6% 4 5% 5% 19%	4440
	21st to end	Night	14% 21% 7% 12% 6% 7% 4 3 4 4 18%	4624
February	1st to 10th	Night	11% 16% 5% 13% 9% 6% 4 4 5% 6% 21%	2470
	11th to 20th	Night	11% 15% 6% 11% 7% 5% 5% 3 5% 5% 27%	2403
	21st to end	Night	13% 15% 5% 11% 6% 5% 4 4 5% 6% 26%	1962
March	1st to 10th	Night	17% 13% 4 9% 5% 4 4 3 4 5% 32%	3549
	11th to 20th	Night	14% 16% 6% 10% 6% 5% 4 3 5% 5% 24%	3479
	21st to end	Night	11% 10% 3 10% 6% 4 4 3 6% 7% 36%	3725
April	1st to 10th	Night	19% 14% 4 8% 6% 3 3 3 5% 5% 31%	1900
	11th to 20th	Night	19% 10% 2 7% 4 4 4 3 4 6% 37%	1875
	21st to end	Night	20% 11% 3 8% 5% 4 4 4 4 5% 32%	1720
May	1st to 10th	Night	20% 8% 3 6% 5% 5% 4 4 5% 6% 35%	2556
	11th to 20th	Night	18% 8% 2 7% 5% 5% 4 3 5% 7% 35%	2495
	21st to end	Night	12% 7% 3 8% 5% 5% 5% 3 6% 6% 40%	2738
June	1st to 10th	Night	17% 8% 3 7% 5% 5% 5% 4 5% 7% 35%	1520
	11th to 20th	Night	13% 7% 2 5% 4 4 6% 4 5% 7% 44%	1520
	21st to end	Night	16% 7% 3 6% 5% 4 5% 4 5% 8% 36%	1520
July	1st to 10th	Night	10% 6% 2 7% 5% 6% 5% 5% 6% 7% 40%	2520
	11th to 20th	Night	14% 5% 2 6% 4 4 4 4 6% 7% 44%	2520
	21st to end	Night	10% 5% 2 6% 4 4 4 4 6% 8% 48%	2739
August	1st to 10th	Night	12% 5% 2 6% 4 5% 5% 4 6% 7% 44%	2747
	11th to 20th	Night	16% 5% 2 5% 4 3 4 4 5% 7% 45%	2785
	21st to end	Night	13% 4 2 6% 4 4 4 4 6% 8% 45%	3348
September	1st to 10th	Night	12% 5% 1 5% 4 4 4 5% 5% 7% 48%	1900
	11th to 20th	Night	14% 5% 2 5% 3 3 4 3 4 6% 50%	1900
	21st to end	Night	17% 8% 2 5% 4 4 3 3 5% 7% 41%	2188
October	1st to 10th	Night	21% 7% 2 6% 3 4 3 3 4 5% 41%	2280
	11th to 20th	Night	20% 11% 3 7% 5% 5% 4 3 5% 6% 30%	2280
	21st to end	Night	22% 13% 3 9% 5% 4 3 4 5% 6% 26%	2583
November	1st to 10th	Night	16% 12% 3 8% 6% 4 4 4 6% 5% 32%	2630
	11th to 20th	Night	16% 14% 4 10% 7% 5% 4 3 6% 5% 26%	2660
	21st to end	Night	21% 16% 5% 10% 7% 4 5% 3 4 5% 21%	2660
December	1st to 10th	Night	18% 21% 6% 11% 7% 5% 4 3 4 4 16%	2660
	11th to 20th	Night	17% 18% 5% 12% 6% 5% 4 3 3 4 23%	3288
	21st to end	Night	25% 20% 6% 14% 5% 4 3 2 3 4 14%	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	66% 8% 12% 9% 6%	2518
	11th to 20th	Day	66% 6% 9% 12% 6% 1	2520
	21st to end	Day	72% 5% 6% 11% 5% 1	3031
February	1st to 10th	Day	65% 5% 9% 15% 5% 1	1710
	11th to 20th	Day	59% 6% 12% 13% 8% 1	1672
	21st to end	Day	61% 5% 8% 14% 10% 1	1490
March	1st to 10th	Day	59% 5% 10% 15% 10% 1	3279
	11th to 20th	Day	58% 6% 11% 14% 9% 1	3480
	21st to end	Day	42% 6% 9% 23% 17% 4	3906
April	1st to 10th	Day	56% 5% 8% 18% 10% 3	2280
	11th to 20th	Day	52% 4 8% 21% 13% 2	2259
	21st to end	Day	53% 4 8% 16% 15% 3	2470
May	1st to 10th	Day	49% 7% 9% 22% 10% 3	4398
	11th to 20th	Day	45% 8% 12% 25% 9% 1	4402
	21st to end	Day	44% 7% 11% 19% 16% 3	4837
June	1st to 10th	Day	52% 7% 10% 19% 11% 1	2660
	11th to 20th	Day	42% 7% 12% 23% 14% 2	2660
	21st to end	Day	47% 8% 12% 20% 12% 1	2660
July	1st to 10th	Day	43% 7% 14% 26% 10% 1	4370
	11th to 20th	Day	38% 8% 14% 30% 10%	4365
	21st to end	Day	35% 7% 12% 33% 13%	4661
August	1st to 10th	Day	47% 7% 13% 24% 9%	4166
	11th to 20th	Day	44% 7% 15% 26% 8% 1	4083
	21st to end	Day	37% 8% 13% 32% 10% 1	4276
September	1st to 10th	Day	40% 8% 13% 27% 12%	2280
	11th to 20th	Day	39% 7% 11% 30% 13%	2280
	21st to end	Day	49% 6% 12% 23% 9%	1990
October	1st to 10th	Day	52% 5% 9% 26% 7%	3160
	11th to 20th	Day	52% 6% 12% 23% 7%	3140
	21st to end	Day	58% 7% 15% 15% 5% 1	3304
November	1st to 10th	Day	52% 5% 14% 22% 7%	1648
	11th to 20th	Day	59% 6% 13% 13% 7% 1	1520
	21st to end	Day	71% 5% 10% 9% 5% 1	1520
December	1st to 10th	Day	73% 5% 8% 9% 4	1520
	11th to 20th	Day	65% 8% 9% 11% 7%	1906
	21st to end	Day	74% 3 6% 14% 3	2772
January	1st to 10th	Night	70% 7% 10% 9% 3	4429
	11th to 20th	Night	63% 10% 12% 10% 4	4440
	21st to end	Night	70% 6% 8% 9% 6%	4624
February	1st to 10th	Night	64% 6% 10% 13% 6% 1	2470
	11th to 20th	Night	59% 5% 10% 18% 6% 1	2405
	21st to end	Night	57% 6% 10% 18% 8% 1	1962
March	1st to 10th	Night	55% 6% 12% 17% 9% 1	3559
	11th to 20th	Night	59% 7% 12% 14% 7% 1	3480
	21st to end	Night	44% 7% 11% 21% 14% 2	3725
April	1st to 10th	Night	55% 5% 8% 18% 11% 2	1900
	11th to 20th	Night	50% 4 8% 23% 13% 2	1875
	21st to end	Night	54% 5% 7% 16% 15% 2	1720
May	1st to 10th	Night	47% 8% 12% 21% 10% 2	2562
	11th to 20th	Night	44% 10% 12% 22% 10% 2	2496
	21st to end	Night	40% 10% 11% 22% 15% 2	2739
June	1st to 10th	Night	47% 8% 11% 22% 11% 1	1520
	11th to 20th	Night	38% 7% 12% 26% 16% 2	1520
	21st to end	Night	44% 8% 13% 20% 13% 1	1520
July	1st to 10th	Night	42% 8% 15% 21% 14% 1	2480
	11th to 20th	Night	39% 7% 13% 32% 9%	2472
	21st to end	Night	33% 8% 13% 31% 14%	2651
August	1st to 10th	Night	38% 7% 14% 27% 14%	2737
	11th to 20th	Night	38% 7% 17% 29% 10%	2812
	21st to end	Night	36% 8% 15% 29% 11% 2	3348
September	1st to 10th	Night	36% 7% 13% 30% 14% 1	1900
	11th to 20th	Night	36% 7% 15% 32% 11%	1900
	21st to end	Night	43% 7% 12% 28% 10%	2188
October	1st to 10th	Night	40% 5% 13% 30% 12%	3800
	11th to 20th	Night	47% 6% 16% 21% 10%	3779
	21st to end	Night	53% 6% 17% 16% 7%	4243
November	1st to 10th	Night	53% 6% 14% 19% 8%	2630
	11th to 20th	Night	59% 7% 12% 15% 7% 1	2660
	21st to end	Night	65% 6% 12% 13% 3	2660
December	1st to 10th	Night	71% 6% 9% 10% 3	2660
	11th to 20th	Night	64% 6% 9% 13% 7% 1	3288
	21st to end	Night	76% 4 6% 11% 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	21% 22% 36% 19% 3 1	180
	11th to 20th	Day	26% 16% 37% 16% 4 1	180
	21st to end	Day	24% 18% 32% 20% 6%	272
February	1st to 10th	Day	24% 28% 34% 10% 3 1	270
	11th to 20th	Day	26% 26% 40% 8% 1	270
	21st to end	Day	34% 19% 34% 12% 1	302
March	1st to 10th	Day	24% 23% 34% 15% 3	460
	11th to 20th	Day	26% 17% 33% 18% 5% 1	460
	21st to end	Day	29% 20% 32% 14% 5% 1	506
April	1st to 10th	Day	28% 21% 30% 15% 6% 1	460
	11th to 20th	Day	34% 18% 23% 14% 8% 3	452
	21st to end	Day	28% 17% 33% 14% 5% 2	460
May	1st to 10th	Day	25% 15% 29% 20% 8% 3	463
	11th to 20th	Day	22% 15% 30% 21% 9% 3	487
	21st to end	Day	17% 17% 33% 20% 10% 2	529
June	1st to 10th	Day	23% 12% 35% 21% 8%	490
	11th to 20th	Day	18% 15% 29% 25% 11% 3	490
	21st to end	Day	18% 15% 33% 23% 9% 3	490
July	1st to 10th	Day	11% 8% 33% 34% 11% 2	485
	11th to 20th	Day	13% 11% 34% 26% 12% 3	484
	21st to end	Day	14% 10% 31% 29% 12% 4	532
August	1st to 10th	Day	16% 7% 32% 25% 15% 5%	486
	11th to 20th	Day	15% 6% 27% 26% 19% 5%	479
	21st to end	Day	15% 9% 32% 25% 12% 6%	539
September	1st to 10th	Day	18% 11% 30% 20% 13% 7%	490
	11th to 20th	Day	14% 10% 23% 23% 19% 11%	490
	21st to end	Day	19% 14% 25% 21% 16% 6%	490
October	1st to 10th	Day	24% 17% 23% 19% 13% 3	490
	11th to 20th	Day	28% 22% 27% 15% 7% 1	490
	21st to end	Day	33% 17% 26% 18% 5%	499
November	1st to 10th	Day	27% 17% 34% 15% 6% 1	288
	11th to 20th	Day	27% 24% 34% 7% 7% 1	180
	21st to end	Day	32% 22% 33% 9% 3 1	180
December	1st to 10th	Day	30% 16% 37% 13% 4	180
	11th to 20th	Day	31% 26% 31% 9% 2 1	180
	21st to end	Day	35% 17% 30% 13% 4 1	198
January	1st to 10th	Night	24% 18% 34% 19% 4	760
	11th to 20th	Night	26% 16% 31% 21% 6%	760
	21st to end	Night	18% 15% 35% 25% 7% 1	836
February	1st to 10th	Night	20% 19% 38% 18% 4	760
	11th to 20th	Night	21% 19% 39% 18% 3	743
	21st to end	Night	22% 20% 31% 24% 3	628
March	1st to 10th	Night	25% 18% 33% 21% 4	760
	11th to 20th	Night	23% 21% 32% 18% 5% 1	760
	21st to end	Night	20% 16% 34% 22% 7%	836
April	1st to 10th	Night	28% 15% 31% 22% 4	760
	11th to 20th	Night	27% 16% 30% 19% 8%	751
	21st to end	Night	24% 14% 27% 25% 9% 1	580
May	1st to 10th	Night	21% 11% 31% 29% 8% 1	409
	11th to 20th	Night	22% 10% 32% 26% 9% 1	374
	21st to end	Night	14% 11% 36% 27% 10%	411
June	1st to 10th	Night	18% 7% 37% 33% 5% 1	380
	11th to 20th	Night	18% 9% 29% 33% 11% 1	380
	21st to end	Night	20% 10% 28% 30% 12%	380
July	1st to 10th	Night	11% 8% 32% 37% 11% 2	370
	11th to 20th	Night	12% 8% 26% 39% 14% 1	368
	21st to end	Night	8% 6% 34% 36% 15%	416
August	1st to 10th	Night	12% 4 27% 34% 22% 1	515
	11th to 20th	Night	12% 4 23% 37% 21% 3	564
	21st to end	Night	14% 8% 29% 31% 17% 2	760
September	1st to 10th	Night	16% 6% 31% 28% 18% 2	760
	11th to 20th	Night	17% 7% 24% 29% 21% 3	760
	21st to end	Night	20% 10% 24% 25% 19% 2	760
October	1st to 10th	Night	25% 10% 28% 22% 13% 1	760
	11th to 20th	Night	26% 17% 27% 20% 9% 1	760
	21st to end	Night	28% 17% 28% 21% 5%	836
November	1st to 10th	Night	26% 17% 28% 22% 6% 1	779
	11th to 20th	Night	23% 21% 30% 16% 9% 1	760
	21st to end	Night	30% 18% 25% 23% 4	760
December	1st to 10th	Night	31% 18% 30% 16% 4	760
	11th to 20th	Night	26% 19% 29% 21% 4	760
	21st to end	Night	33% 16% 27% 19% 3 1	836

Page generated at 2024-11-07 06:55:48. Version ac07

Copyright © 2024 Attilla Danko.