Campbellford
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Campbellford clear sky chart from 2005-11-06 to 2024-07-31.

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% 3 7% 5% 5% 4 4 5% 7% 34%	90045
	Night	16% 10% 3 8% 5% 4 4 4 5% 6% 34%	89779
Transparency	Day	48% 8% 13% 19% 11% 1	89764
	Night	49% 8% 13% 19% 10% 1	89613
Seeing	Day	21% 17% 31% 20% 9% 3	14087
	Night	20% 13% 31% 25% 10% 1	23340

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% 4 9% 4 3 4 2 5% 5% 32%	2517
	11th to 20th	Day	12% 17% 6% 14% 8% 6% 5% 3 4 4 21%	2534
	21st to end	Day	20% 19% 6% 12% 6% 5% 3 3 4 3 20%	3124
February	1st to 10th	Day	14% 15% 5% 10% 7% 6% 5% 4 5% 5% 24%	1710
	11th to 20th	Day	11% 14% 5% 13% 6% 6% 4 3 4 6% 28%	1663
	21st to end	Day	19% 13% 5% 9% 6% 5% 5% 3 4 5% 26%	1499
March	1st to 10th	Day	20% 13% 3 8% 5% 4 4 3 4 6% 31%	3330
	11th to 20th	Day	11% 15% 4 9% 5% 4 5% 4 4 6% 32%	3480
	21st to end	Day	14% 8% 3 6% 4 3 3 3 5% 6% 46%	3878
April	1st to 10th	Day	20% 12% 3 6% 6% 4 4 3 4 5% 32%	2280
	11th to 20th	Day	22% 9% 2 5% 4 4 3 2 4 6% 38%	2254
	21st to end	Day	21% 8% 3 8% 5% 4 5% 3 4 5% 34%	2452
May	1st to 10th	Day	19% 7% 3 7% 4 5% 4 3 5% 7% 34%	4290
	11th to 20th	Day	16% 10% 3 7% 5% 4 4 4 7% 7% 33%	4398
	21st to end	Day	12% 5% 2 5% 4 5% 5% 4 6% 8% 43%	4837
June	1st to 10th	Day	17% 7% 3 7% 5% 4 5% 5% 6% 8% 33%	2660
	11th to 20th	Day	13% 6% 2 6% 4 5% 5% 4 7% 9% 39%	2660
	21st to end	Day	16% 7% 3 7% 5% 4 5% 4 6% 9% 36%	2660
July	1st to 10th	Day	10% 5% 2 5% 5% 5% 5% 5% 7% 8% 43%	2660
	11th to 20th	Day	11% 5% 2 5% 5% 5% 7% 5% 6% 9% 40%	2660
	21st to end	Day	9% 5% 2 7% 5% 6% 6% 6% 7% 8% 39%	2858
August	1st to 10th	Day	9% 6% 3 6% 5% 5% 5% 5% 7% 9% 41%	2327
	11th to 20th	Day	10% 6% 3 7% 5% 5% 6% 4 7% 9% 38%	2303
	21st to end	Day	13% 5% 2 6% 4 5% 4 4 7% 8% 41%	2417
September	1st to 10th	Day	13% 5% 2 6% 4 5% 5% 4 6% 9% 41%	2160
	11th to 20th	Day	11% 5% 2 5% 4 4 4 4 6% 7% 49%	2160
	21st to end	Day	15% 6% 3 7% 4 4 5% 4 5% 6% 41%	1878
October	1st to 10th	Day	19% 8% 3 8% 4 4 4 4 5% 7% 34%	1800
	11th to 20th	Day	20% 9% 3 8% 5% 5% 4 4 4 7% 29%	1800
	21st to end	Day	25% 11% 3 7% 5% 5% 4 4 4 6% 26%	1953
November	1st to 10th	Day	15% 9% 3 6% 5% 5% 5% 4 6% 6% 35%	1605
	11th to 20th	Day	15% 11% 4 9% 5% 4 4 4 5% 8% 30%	1520
	21st to end	Day	21% 13% 4 8% 5% 5% 5% 4 5% 6% 25%	1520
December	1st to 10th	Day	17% 16% 5% 10% 6% 5% 5% 3 4 6% 22%	1520
	11th to 20th	Day	17% 16% 5% 9% 5% 5% 4 3 4 4 29%	1906
	21st to end	Day	28% 15% 5% 9% 5% 4 3 3 4 5% 20%	2772
January	1st to 10th	Night	18% 14% 5% 9% 5% 5% 6% 4 5% 5% 24%	4429
	11th to 20th	Night	14% 12% 6% 13% 7% 6% 5% 3 5% 5% 23%	4408
	21st to end	Night	19% 15% 7% 10% 5% 4 4 3 4 5% 23%	4532
February	1st to 10th	Night	13% 15% 4 10% 7% 5% 5% 4 5% 6% 26%	2470
	11th to 20th	Night	13% 13% 5% 9% 5% 5% 5% 4 6% 6% 29%	2403
	21st to end	Night	15% 11% 4 9% 4 4 4 4 5% 7% 32%	1954
March	1st to 10th	Night	19% 10% 4 9% 5% 4 4 4 5% 6% 32%	3509
	11th to 20th	Night	15% 12% 5% 9% 5% 5% 5% 4 5% 6% 30%	3479
	21st to end	Night	16% 7% 2 5% 4 3 3 3 4 6% 46%	3754
April	1st to 10th	Night	20% 9% 3 6% 5% 4 4 3 4 6% 36%	1900
	11th to 20th	Night	18% 8% 3 7% 4 4 4 4 5% 6% 38%	1875
	21st to end	Night	18% 7% 3 7% 4 5% 4 5% 6% 7% 34%	1743
May	1st to 10th	Night	21% 7% 4 6% 4 5% 5% 3 5% 6% 36%	2651
	11th to 20th	Night	16% 8% 2 7% 4 4 5% 4 6% 7% 37%	2495
	21st to end	Night	10% 6% 2 6% 4 4 4 3 5% 8% 47%	2738
June	1st to 10th	Night	14% 5% 3 7% 6% 5% 5% 4 6% 9% 38%	1520
	11th to 20th	Night	10% 6% 2 5% 4 5% 5% 4 7% 7% 45%	1520
	21st to end	Night	13% 7% 2 7% 4 5% 4 4 5% 7% 41%	1520
July	1st to 10th	Night	6% 5% 2 5% 5% 5% 4 3 7% 7% 52%	1520
	11th to 20th	Night	10% 5% 2 4 4 4 5% 4 7% 8% 48%	1520
	21st to end	Night	9% 5% 1 5% 4 4 4 4 6% 8% 50%	1688
August	1st to 10th	Night	8% 5% 2 6% 4 4 3 3 6% 9% 48%	1611
	11th to 20th	Night	8% 6% 2 6% 4 4 5% 3 6% 9% 47%	1598
	21st to end	Night	9% 6% 3 6% 4 4 5% 4 6% 8% 47%	1921
September	1st to 10th	Night	11% 6% 2 6% 4 4 3 4 6% 8% 45%	1800
	11th to 20th	Night	12% 4 2 5% 3 4 3 3 6% 7% 52%	1800
	21st to end	Night	15% 7% 2 6% 4 4 4 3 4 5% 45%	2078
October	1st to 10th	Night	17% 7% 2 6% 5% 4 4 3 6% 6% 38%	2160
	11th to 20th	Night	20% 8% 3 8% 5% 5% 4 3 4 6% 33%	2160
	21st to end	Night	21% 11% 3 8% 5% 5% 5% 3 5% 6% 29%	2402
November	1st to 10th	Night	18% 9% 2 6% 4 4 4 4 5% 6% 39%	2469
	11th to 20th	Night	17% 10% 3 7% 6% 4 5% 4 5% 8% 31%	2660
	21st to end	Night	20% 11% 3 8% 5% 5% 5% 5% 6% 6% 27%	2660
December	1st to 10th	Night	19% 14% 4 8% 5% 5% 4 4 6% 7% 22%	2660
	11th to 20th	Night	18% 15% 4 9% 5% 5% 4 3 5% 5% 28%	3288
	21st to end	Night	29% 16% 3 10% 5% 4 4 3 4 5% 16%	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	54% 8% 16% 14% 7% 2	2518
	11th to 20th	Day	65% 7% 10% 10% 7%	2534
	21st to end	Day	68% 7% 9% 10% 5% 1	3124
February	1st to 10th	Day	60% 8% 11% 15% 5% 1	1710
	11th to 20th	Day	57% 6% 11% 14% 10% 1	1672
	21st to end	Day	60% 6% 11% 13% 9% 1	1499
March	1st to 10th	Day	53% 7% 13% 17% 9% 1	3333
	11th to 20th	Day	50% 8% 17% 15% 9% 2	3480
	21st to end	Day	39% 6% 10% 26% 17% 3	3878
April	1st to 10th	Day	53% 6% 9% 19% 11% 2	2280
	11th to 20th	Day	47% 4 11% 21% 15% 1	2254
	21st to end	Day	51% 7% 10% 17% 13% 2	2452
May	1st to 10th	Day	47% 8% 11% 20% 12% 2	4302
	11th to 20th	Day	47% 9% 14% 20% 10% 1	4402
	21st to end	Day	36% 8% 14% 24% 15% 3	4837
June	1st to 10th	Day	46% 9% 13% 17% 13% 1	2660
	11th to 20th	Day	39% 8% 14% 23% 13% 1	2660
	21st to end	Day	43% 8% 13% 22% 12% 1	2660
July	1st to 10th	Day	34% 8% 14% 26% 16% 1	2590
	11th to 20th	Day	37% 9% 17% 27% 10%	2585
	21st to end	Day	38% 11% 15% 25% 11% 1	2706
August	1st to 10th	Day	35% 10% 18% 24% 11% 1	2314
	11th to 20th	Day	38% 9% 17% 24% 11%	2303
	21st to end	Day	37% 9% 15% 26% 11% 1	2417
September	1st to 10th	Day	37% 8% 15% 27% 12% 1	2160
	11th to 20th	Day	32% 8% 15% 29% 15% 1	2160
	21st to end	Day	41% 8% 16% 27% 8%	1878
October	1st to 10th	Day	48% 7% 14% 19% 11% 1	1800
	11th to 20th	Day	53% 8% 15% 17% 6% 1	1800
	21st to end	Day	59% 7% 11% 14% 8%	1953
November	1st to 10th	Day	46% 8% 16% 19% 10% 1	1605
	11th to 20th	Day	51% 8% 15% 15% 9% 1	1520
	21st to end	Day	59% 8% 13% 13% 7%	1520
December	1st to 10th	Day	63% 8% 12% 12% 6%	1520
	11th to 20th	Day	58% 8% 13% 12% 8%	1906
	21st to end	Day	67% 6% 10% 12% 5%	2772
January	1st to 10th	Night	59% 9% 14% 12% 5%	4429
	11th to 20th	Night	59% 11% 12% 12% 4 1	4408
	21st to end	Night	63% 8% 11% 12% 6%	4532
February	1st to 10th	Night	58% 7% 13% 17% 5% 1	2470
	11th to 20th	Night	54% 7% 11% 19% 8%	2405
	21st to end	Night	50% 7% 14% 19% 9% 1	1954
March	1st to 10th	Night	52% 7% 10% 20% 10% 1	3519
	11th to 20th	Night	50% 8% 16% 16% 8% 1	3480
	21st to end	Night	37% 5% 12% 25% 18% 2	3754
April	1st to 10th	Night	49% 5% 10% 20% 13% 2	1900
	11th to 20th	Night	46% 6% 12% 18% 17% 2	1875
	21st to end	Night	45% 9% 13% 16% 15% 2	1743
May	1st to 10th	Night	47% 8% 13% 16% 14% 2	2658
	11th to 20th	Night	43% 9% 14% 22% 10% 2	2496
	21st to end	Night	34% 9% 13% 22% 20% 2	2739
June	1st to 10th	Night	42% 7% 12% 23% 14% 2	1520
	11th to 20th	Night	35% 8% 13% 21% 20% 3	1520
	21st to end	Night	41% 7% 15% 22% 14% 2	1520
July	1st to 10th	Night	30% 7% 13% 26% 23% 2	1480
	11th to 20th	Night	33% 7% 14% 30% 16%	1472
	21st to end	Night	31% 7% 16% 32% 12% 1	1599
August	1st to 10th	Night	33% 8% 17% 28% 13% 1	1600
	11th to 20th	Night	33% 8% 19% 26% 14% 1	1598
	21st to end	Night	33% 9% 13% 29% 14% 1	1921
September	1st to 10th	Night	35% 9% 16% 25% 14% 1	1800
	11th to 20th	Night	31% 7% 14% 31% 17% 1	1800
	21st to end	Night	40% 8% 11% 28% 12% 1	2078
October	1st to 10th	Night	44% 8% 13% 20% 13% 1	2160
	11th to 20th	Night	52% 7% 14% 20% 8%	2160
	21st to end	Night	56% 7% 12% 14% 10%	2402
November	1st to 10th	Night	45% 7% 14% 23% 11% 1	2469
	11th to 20th	Night	49% 9% 14% 17% 9% 2	2660
	21st to end	Night	53% 10% 16% 16% 5%	2660
December	1st to 10th	Night	59% 9% 14% 14% 4	2660
	11th to 20th	Night	58% 8% 12% 16% 6% 1	3288
	21st to end	Night	69% 7% 10% 10% 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% 24% 32% 16% 4 1	180
	11th to 20th	Day	26% 25% 30% 16% 3 1	186
	21st to end	Day	27% 23% 30% 14% 4 1	297
February	1st to 10th	Day	30% 26% 30% 11% 2	270
	11th to 20th	Day	27% 28% 37% 8%	270
	21st to end	Day	34% 23% 34% 9%	311
March	1st to 10th	Day	23% 22% 36% 15% 4	460
	11th to 20th	Day	26% 23% 32% 15% 3	460
	21st to end	Day	32% 17% 32% 13% 5% 1	506
April	1st to 10th	Day	27% 21% 35% 11% 6%	460
	11th to 20th	Day	31% 21% 23% 15% 8% 3	452
	21st to end	Day	27% 22% 31% 13% 5% 2	460
May	1st to 10th	Day	22% 18% 31% 19% 6% 4	463
	11th to 20th	Day	19% 15% 34% 21% 9% 3	487
	21st to end	Day	15% 13% 36% 20% 12% 4	529
June	1st to 10th	Day	18% 14% 35% 24% 7% 2	490
	11th to 20th	Day	14% 15% 31% 24% 13% 3	490
	21st to end	Day	21% 12% 32% 24% 9% 3	490
July	1st to 10th	Day	10% 10% 32% 29% 15% 4	485
	11th to 20th	Day	15% 9% 30% 25% 16% 5%	484
	21st to end	Day	9% 10% 35% 29% 12% 5%	529
August	1st to 10th	Day	8% 8% 31% 30% 15% 7%	446
	11th to 20th	Day	12% 6% 28% 29% 18% 7%	439
	21st to end	Day	13% 11% 31% 25% 13% 8%	495
September	1st to 10th	Day	11% 10% 33% 26% 12% 8%	450
	11th to 20th	Day	12% 10% 26% 26% 17% 10%	450
	21st to end	Day	15% 15% 28% 24% 13% 6%	450
October	1st to 10th	Day	22% 19% 23% 17% 14% 6%	450
	11th to 20th	Day	24% 21% 31% 16% 7% 1	450
	21st to end	Day	31% 19% 27% 19% 4	481
November	1st to 10th	Day	24% 20% 26% 19% 10% 1	299
	11th to 20th	Day	24% 24% 33% 14% 4 1	180
	21st to end	Day	24% 24% 33% 13% 5%	180
December	1st to 10th	Day	28% 19% 33% 14% 5%	180
	11th to 20th	Day	32% 23% 30% 12% 2 1	180
	21st to end	Day	36% 20% 33% 10% 1	198
January	1st to 10th	Night	25% 21% 31% 18% 4	760
	11th to 20th	Night	25% 18% 33% 19% 5%	760
	21st to end	Night	20% 16% 34% 23% 5%	836
February	1st to 10th	Night	21% 20% 38% 18% 2	760
	11th to 20th	Night	22% 19% 38% 17% 4	743
	21st to end	Night	23% 21% 35% 18% 4	628
March	1st to 10th	Night	20% 19% 37% 21% 4	760
	11th to 20th	Night	24% 17% 34% 20% 4 1	760
	21st to end	Night	20% 15% 34% 23% 7% 1	836
April	1st to 10th	Night	23% 16% 35% 23% 3	760
	11th to 20th	Night	22% 17% 32% 21% 8% 1	751
	21st to end	Night	21% 11% 32% 25% 10% 1	603
May	1st to 10th	Night	21% 9% 30% 27% 11% 2	466
	11th to 20th	Night	14% 9% 36% 32% 10%	374
	21st to end	Night	12% 6% 33% 34% 14% 1	411
June	1st to 10th	Night	13% 7% 36% 31% 13% 1	380
	11th to 20th	Night	10% 9% 30% 35% 15% 1	380
	21st to end	Night	14% 8% 28% 36% 14% 1	380
July	1st to 10th	Night	6% 5% 29% 43% 16% 1	370
	11th to 20th	Night	10% 3 28% 36% 23% 1	368
	21st to end	Night	10% 2 29% 41% 17% 1	442
August	1st to 10th	Night	10% 4 22% 36% 27% 2	537
	11th to 20th	Night	8% 7% 21% 37% 25% 3	534
	21st to end	Night	11% 5% 28% 34% 19% 2	733
September	1st to 10th	Night	12% 6% 30% 31% 19% 3	720
	11th to 20th	Night	13% 6% 22% 31% 25% 4	720
	21st to end	Night	17% 9% 24% 27% 19% 3	720
October	1st to 10th	Night	22% 9% 28% 23% 16% 2	720
	11th to 20th	Night	22% 16% 31% 23% 9%	720
	21st to end	Night	27% 14% 33% 22% 5%	792
November	1st to 10th	Night	24% 13% 25% 28% 9% 1	740
	11th to 20th	Night	22% 18% 33% 20% 6% 1	760
	21st to end	Night	27% 16% 32% 20% 6%	760
December	1st to 10th	Night	28% 19% 32% 18% 3	760
	11th to 20th	Night	25% 18% 34% 18% 3	760
	21st to end	Night	32% 16% 34% 15% 3	836

Page generated at 2024-07-28 09:52:08. Version ac07

Copyright © 2024 Attilla Danko.