Parc national d'Oka
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Parc national d'Oka clear sky chart from 2005-11-06 to 2024-11-03.

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% 9% 3 8% 5% 5% 5% 4 5% 7% 33%	101538
	Night	18% 11% 4 8% 5% 4 4 3 5% 6% 32%	97464
Transparency	Day	50% 5% 13% 22% 10% 1	101299
	Night	53% 4 12% 20% 10% 1	97323
Seeing	Day	20% 9% 28% 26% 13% 4	14558
	Night	22% 8% 28% 30% 11% 1	23518

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% 15% 5% 14% 6% 5% 5% 3 4 4 23%	2517
	11th to 20th	Day	15% 13% 5% 10% 6% 5% 5% 4 6% 6% 25%	2520
	21st to end	Day	14% 17% 5% 10% 5% 5% 5% 4 6% 6% 23%	2772
February	1st to 10th	Day	14% 16% 4 11% 6% 4 5% 4 4 6% 25%	1686
	11th to 20th	Day	14% 12% 4 10% 6% 5% 5% 5% 6% 5% 28%	1748
	21st to end	Day	18% 15% 4 9% 6% 4 3 3 4 5% 27%	1570
March	1st to 10th	Day	20% 13% 5% 9% 6% 4 4 3 4 5% 27%	3116
	11th to 20th	Day	11% 16% 5% 12% 6% 5% 5% 4 5% 5% 27%	3310
	21st to end	Day	14% 7% 3 8% 5% 5% 4 3 5% 6% 39%	4152
April	1st to 10th	Day	21% 11% 3 7% 5% 4 3 3 5% 5% 33%	2280
	11th to 20th	Day	21% 8% 3 7% 4 4 4 3 5% 5% 36%	2254
	21st to end	Day	22% 9% 3 7% 4 4 4 4 4 6% 32%	2418
May	1st to 10th	Day	19% 8% 3 8% 5% 5% 5% 4 5% 7% 30%	4391
	11th to 20th	Day	17% 8% 4 8% 5% 4 5% 4 5% 7% 34%	4398
	21st to end	Day	15% 6% 2 7% 5% 4 5% 4 7% 8% 37%	4837
June	1st to 10th	Day	21% 8% 3 7% 4 5% 5% 4 6% 7% 30%	2660
	11th to 20th	Day	14% 6% 2 7% 6% 4 5% 4 6% 8% 38%	2660
	21st to end	Day	19% 8% 3 7% 6% 5% 5% 4 6% 7% 31%	2660
July	1st to 10th	Day	11% 6% 3 7% 6% 6% 5% 4 6% 8% 37%	4440
	11th to 20th	Day	13% 6% 2 6% 4 5% 5% 5% 7% 9% 38%	4440
	21st to end	Day	11% 6% 2 5% 4 4 5% 4 6% 8% 45%	4814
August	1st to 10th	Day	14% 6% 3 8% 5% 5% 5% 4 7% 9% 34%	4423
	11th to 20th	Day	14% 6% 3 7% 5% 5% 4 4 5% 9% 39%	3985
	21st to end	Day	16% 4 2 6% 4 4 5% 4 6% 9% 40%	4180
September	1st to 10th	Day	11% 6% 3 6% 4 4 5% 4 6% 8% 42%	2280
	11th to 20th	Day	13% 5% 2 5% 4 4 4 4 5% 7% 49%	2213
	21st to end	Day	17% 5% 2 6% 4 4 4 4 5% 7% 41%	2090
October	1st to 10th	Day	20% 7% 3 7% 5% 4 4 4 5% 5% 37%	1943
	11th to 20th	Day	18% 9% 2 8% 7% 6% 5% 4 5% 6% 30%	1873
	21st to end	Day	23% 11% 3 7% 4 3 4 3 6% 7% 29%	1881
November	1st to 10th	Day	17% 9% 3 7% 6% 4 4 4 6% 7% 33%	1689
	11th to 20th	Day	18% 10% 4 8% 5% 5% 5% 3 6% 7% 28%	1620
	21st to end	Day	22% 11% 3 8% 6% 6% 6% 4 6% 6% 24%	1520
December	1st to 10th	Day	24% 15% 5% 10% 6% 4 5% 3 5% 5% 19%	1520
	11th to 20th	Day	21% 14% 4 8% 6% 4 4 4 5% 4 26%	1906
	21st to end	Day	28% 16% 5% 10% 5% 4 4 2 3 3 20%	2772
January	1st to 10th	Night	17% 16% 6% 9% 6% 5% 5% 3 4 6% 23%	4429
	11th to 20th	Night	12% 14% 5% 13% 7% 6% 5% 4 5% 6% 22%	4440
	21st to end	Night	16% 17% 5% 10% 6% 5% 5% 3 4 5% 24%	4884
February	1st to 10th	Night	14% 14% 5% 11% 7% 5% 4 5% 6% 6% 23%	2490
	11th to 20th	Night	14% 10% 3 10% 6% 5% 6% 4 6% 7% 29%	2317
	21st to end	Night	15% 15% 4 9% 5% 4 4 4 3 4 31%	1884
March	1st to 10th	Night	21% 11% 3 8% 5% 4 4 3 4 5% 33%	3724
	11th to 20th	Night	18% 18% 5% 9% 5% 5% 3 3 5% 4 27%	3645
	21st to end	Night	13% 10% 3 9% 5% 4 4 3 5% 5% 39%	3480
April	1st to 10th	Night	23% 9% 3 6% 5% 4 4 4 4 6% 31%	1900
	11th to 20th	Night	22% 9% 2 7% 5% 3 4 3 5% 7% 33%	1875
	21st to end	Night	21% 9% 4 6% 5% 3 4 3 5% 5% 34%	1762
May	1st to 10th	Night	22% 10% 3 7% 5% 4 3 4 5% 6% 30%	2578
	11th to 20th	Night	23% 7% 2 5% 4 4 4 2 4 6% 38%	2495
	21st to end	Night	16% 7% 2 8% 5% 4 4 3 5% 8% 37%	2738
June	1st to 10th	Night	20% 7% 2 8% 5% 5% 4 5% 6% 8% 31%	1520
	11th to 20th	Night	16% 7% 3 6% 4 3 4 5% 6% 8% 39%	1520
	21st to end	Night	18% 7% 2 7% 5% 5% 5% 4 6% 7% 34%	1520
July	1st to 10th	Night	14% 7% 3 7% 5% 5% 5% 4 7% 7% 35%	2520
	11th to 20th	Night	14% 5% 3 7% 5% 4 4 4 6% 9% 41%	2520
	21st to end	Night	11% 7% 3 5% 5% 5% 4 3 6% 8% 44%	2739
August	1st to 10th	Night	15% 7% 3 8% 4 4 4 4 5% 8% 38%	2506
	11th to 20th	Night	15% 7% 3 7% 4 5% 4 4 5% 7% 39%	2807
	21st to end	Night	16% 6% 3 7% 5% 5% 4 4 6% 6% 40%	3476
September	1st to 10th	Night	11% 5% 3 7% 5% 4 5% 4 5% 8% 43%	1900
	11th to 20th	Night	15% 6% 2 5% 4 3 3 2 4 7% 50%	1966
	21st to end	Night	16% 6% 2 5% 4 4 4 3 5% 7% 43%	2090
October	1st to 10th	Night	18% 7% 3 7% 4 4 4 4 5% 6% 37%	2233
	11th to 20th	Night	20% 8% 3 8% 5% 5% 4 4 4 6% 35%	2305
	21st to end	Night	22% 8% 3 8% 5% 5% 5% 3 5% 6% 30%	2717
November	1st to 10th	Night	19% 9% 3 7% 5% 4 4 4 5% 7% 32%	2434
	11th to 20th	Night	18% 10% 3 8% 5% 4 4 4 6% 5% 32%	2558
	21st to end	Night	22% 13% 4 8% 5% 4 4 3 4 5% 26%	2660
December	1st to 10th	Night	21% 16% 4 10% 6% 4 4 4 5% 5% 21%	2660
	11th to 20th	Night	22% 16% 3 9% 5% 4 4 3 4 4 25%	3288
	21st to end	Night	29% 16% 4 9% 4 3 3 2 4 4 21%	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	63% 3 15% 13% 5% 1	2518
	11th to 20th	Day	58% 5% 13% 16% 8% 1	2520
	21st to end	Day	61% 5% 16% 13% 5%	2772
February	1st to 10th	Day	60% 4 10% 19% 5% 2	1686
	11th to 20th	Day	56% 4 13% 17% 9% 1	1757
	21st to end	Day	60% 3 10% 15% 9% 2	1570
March	1st to 10th	Day	61% 3 9% 19% 8% 1	3119
	11th to 20th	Day	58% 3 12% 14% 11% 2	3310
	21st to end	Day	46% 4 9% 21% 18% 2	4152
April	1st to 10th	Day	53% 4 7% 21% 12% 2	2280
	11th to 20th	Day	49% 3 8% 22% 16% 2	2254
	21st to end	Day	54% 3 9% 18% 13% 4	2418
May	1st to 10th	Day	53% 5% 9% 22% 10% 1	4405
	11th to 20th	Day	50% 4 15% 21% 9% 2	4402
	21st to end	Day	43% 5% 13% 25% 13% 2	4837
June	1st to 10th	Day	51% 5% 11% 20% 12% 1	2660
	11th to 20th	Day	43% 5% 12% 23% 14% 3	2660
	21st to end	Day	51% 5% 14% 20% 10% 1	2660
July	1st to 10th	Day	42% 5% 14% 27% 11%	4370
	11th to 20th	Day	40% 5% 17% 31% 8%	4365
	21st to end	Day	36% 6% 14% 34% 10%	4661
August	1st to 10th	Day	45% 5% 17% 24% 8%	4409
	11th to 20th	Day	42% 5% 18% 29% 6%	4027
	21st to end	Day	39% 6% 18% 23% 14% 1	4180
September	1st to 10th	Day	37% 6% 15% 29% 13%	2280
	11th to 20th	Day	35% 4 13% 32% 15% 1	2213
	21st to end	Day	42% 5% 14% 27% 11% 1	2090
October	1st to 10th	Day	49% 5% 12% 24% 11%	1943
	11th to 20th	Day	54% 4 15% 20% 7%	1873
	21st to end	Day	55% 4 14% 19% 8% 1	1881
November	1st to 10th	Day	48% 5% 16% 22% 8% 1	1689
	11th to 20th	Day	55% 5% 11% 19% 10%	1620
	21st to end	Day	60% 6% 13% 16% 5% 1	1520
December	1st to 10th	Day	68% 5% 11% 13% 4	1520
	11th to 20th	Day	61% 6% 12% 16% 5%	1906
	21st to end	Day	70% 3 10% 12% 5%	2772
January	1st to 10th	Night	64% 3 15% 13% 4	4429
	11th to 20th	Night	61% 5% 13% 16% 4 1	4440
	21st to end	Night	64% 4 13% 12% 6% 1	4884
February	1st to 10th	Night	62% 6% 9% 17% 6% 1	2490
	11th to 20th	Night	53% 5% 12% 21% 8% 1	2319
	21st to end	Night	56% 3 9% 18% 13% 1	1884
March	1st to 10th	Night	55% 3 10% 20% 10% 3	3734
	11th to 20th	Night	61% 3 9% 15% 11% 2	3646
	21st to end	Night	48% 3 5% 24% 16% 3	3480
April	1st to 10th	Night	54% 4 8% 19% 14% 2	1900
	11th to 20th	Night	52% 4 7% 21% 14% 2	1875
	21st to end	Night	51% 4 7% 20% 14% 4	1762
May	1st to 10th	Night	54% 4 11% 20% 9% 3	2584
	11th to 20th	Night	48% 4 13% 21% 12% 2	2496
	21st to end	Night	46% 3 11% 20% 18% 1	2739
June	1st to 10th	Night	51% 6% 10% 21% 12% 1	1520
	11th to 20th	Night	42% 4 12% 23% 16% 2	1520
	21st to end	Night	48% 5% 13% 19% 14% 1	1520
July	1st to 10th	Night	46% 5% 14% 21% 13%	2480
	11th to 20th	Night	40% 5% 17% 29% 9%	2472
	21st to end	Night	38% 5% 17% 26% 13%	2651
August	1st to 10th	Night	44% 5% 15% 28% 9%	2496
	11th to 20th	Night	44% 5% 19% 24% 8%	2831
	21st to end	Night	43% 5% 15% 22% 13% 1	3476
September	1st to 10th	Night	39% 6% 11% 27% 16% 1	1900
	11th to 20th	Night	36% 3 13% 34% 13% 1	1966
	21st to end	Night	41% 6% 11% 27% 14%	2090
October	1st to 10th	Night	46% 6% 10% 24% 12% 1	2233
	11th to 20th	Night	51% 4 12% 25% 9%	2305
	21st to end	Night	56% 4 14% 17% 9% 1	2717
November	1st to 10th	Night	52% 4 12% 22% 9% 1	2434
	11th to 20th	Night	53% 5% 13% 18% 10% 1	2558
	21st to end	Night	61% 5% 11% 16% 6%	2660
December	1st to 10th	Night	66% 5% 11% 15% 4	2660
	11th to 20th	Night	63% 5% 8% 17% 6%	3288
	21st to end	Night	68% 4 9% 15% 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	23% 12% 28% 25% 11% 1	180
	11th to 20th	Day	28% 12% 32% 21% 7% 1	180
	21st to end	Day	20% 11% 35% 24% 9% 1	198
February	1st to 10th	Day	29% 16% 34% 15% 5%	258
	11th to 20th	Day	22% 10% 41% 23% 3	355
	21st to end	Day	28% 9% 30% 29% 4	382
March	1st to 10th	Day	23% 10% 35% 24% 8%	460
	11th to 20th	Day	19% 13% 35% 23% 7% 2	460
	21st to end	Day	24% 10% 31% 19% 13% 2	506
April	1st to 10th	Day	27% 11% 26% 23% 10% 2	460
	11th to 20th	Day	26% 13% 27% 20% 11% 3	452
	21st to end	Day	27% 11% 28% 22% 10% 2	460
May	1st to 10th	Day	21% 9% 29% 27% 10% 3	463
	11th to 20th	Day	18% 6% 30% 25% 16% 4	487
	21st to end	Day	17% 9% 29% 26% 13% 5%	529
June	1st to 10th	Day	21% 9% 23% 30% 13% 4	490
	11th to 20th	Day	16% 8% 25% 31% 17% 2	490
	21st to end	Day	22% 7% 25% 25% 15% 5%	490
July	1st to 10th	Day	10% 8% 25% 31% 20% 7%	485
	11th to 20th	Day	13% 6% 26% 31% 18% 6%	484
	21st to end	Day	13% 6% 21% 36% 19% 5%	532
August	1st to 10th	Day	15% 5% 20% 31% 21% 7%	486
	11th to 20th	Day	12% 4 20% 33% 22% 10%	479
	21st to end	Day	14% 6% 25% 25% 20% 9%	539
September	1st to 10th	Day	15% 7% 24% 26% 19% 9%	490
	11th to 20th	Day	13% 6% 21% 25% 21% 13%	490
	21st to end	Day	18% 8% 25% 24% 19% 6%	490
October	1st to 10th	Day	21% 9% 25% 25% 14% 6%	490
	11th to 20th	Day	20% 12% 30% 23% 13% 2	475
	21st to end	Day	29% 12% 25% 24% 9%	429
November	1st to 10th	Day	26% 12% 23% 27% 9% 1	371
	11th to 20th	Day	23% 14% 34% 20% 8% 1	280
	21st to end	Day	25% 14% 33% 21% 7% 1	180
December	1st to 10th	Day	32% 8% 27% 24% 8% 1	180
	11th to 20th	Day	24% 13% 39% 17% 6% 1	180
	21st to end	Day	32% 13% 29% 18% 6% 2	198
January	1st to 10th	Night	25% 12% 30% 28% 5%	760
	11th to 20th	Night	27% 9% 33% 26% 5% 1	760
	21st to end	Night	19% 10% 34% 28% 8% 1	836
February	1st to 10th	Night	21% 10% 36% 26% 6% 1	760
	11th to 20th	Night	20% 11% 36% 29% 5%	743
	21st to end	Night	22% 9% 34% 29% 5%	628
March	1st to 10th	Night	24% 11% 31% 29% 6%	760
	11th to 20th	Night	25% 10% 30% 27% 7% 1	760
	21st to end	Night	22% 9% 29% 31% 9%	836
April	1st to 10th	Night	27% 10% 26% 31% 6%	760
	11th to 20th	Night	25% 11% 30% 28% 7% 1	751
	21st to end	Night	26% 9% 27% 28% 9%	622
May	1st to 10th	Night	25% 6% 29% 29% 9% 2	418
	11th to 20th	Night	21% 7% 26% 34% 10% 1	374
	21st to end	Night	15% 5% 32% 38% 10%	411
June	1st to 10th	Night	25% 4 26% 34% 11% 1	380
	11th to 20th	Night	17% 5% 25% 36% 16% 1	380
	21st to end	Night	19% 6% 26% 32% 17% 1	380
July	1st to 10th	Night	12% 4 24% 40% 19% 1	370
	11th to 20th	Night	11% 3 24% 44% 17% 1	368
	21st to end	Night	13% 4 21% 42% 17% 1	416
August	1st to 10th	Night	16% 3 15% 44% 21% 1	378
	11th to 20th	Night	14% 3 19% 36% 25% 3	570
	21st to end	Night	15% 3 22% 35% 22% 2	836
September	1st to 10th	Night	14% 4 23% 39% 19% 1	760
	11th to 20th	Night	18% 5% 17% 35% 23% 3	760
	21st to end	Night	19% 6% 23% 31% 19% 2	760
October	1st to 10th	Night	21% 7% 26% 31% 14% 1	760
	11th to 20th	Night	23% 9% 28% 29% 11% 1	760
	21st to end	Night	26% 10% 30% 28% 6%	836
November	1st to 10th	Night	25% 11% 29% 26% 9% 1	749
	11th to 20th	Night	23% 13% 33% 20% 9% 1	760
	21st to end	Night	29% 12% 29% 21% 8% 1	760
December	1st to 10th	Night	31% 11% 30% 23% 5%	760
	11th to 20th	Night	29% 13% 29% 23% 5% 1	760
	21st to end	Night	35% 11% 27% 22% 5%	836

Page generated at 2024-10-31 03:39:24. Version ac07

Copyright © 2024 Attilla Danko.