Quispamsis
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Quispamsis clear sky chart from 2005-11-06 to 2026-10-14.

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	20% 10% 3 7% 4 4 4 3 5% 6% 33%	149785
	Night	20% 11% 3 7% 4 4 4 3 5% 5% 32%	142131
Transparency	Day	51% 5% 11% 21% 11% 1	153306
	Night	53% 4 10% 20% 11% 1	146699
Seeing	Day	30% 19% 30% 16% 5% 1	19161
	Night	28% 16% 28% 21% 6%	26841

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	12% 16% 5% 11% 6% 5% 4 3 4 5% 30%	4093
	11th to 20th	Day	16% 16% 5% 12% 6% 4 3 2 3 3 30%	4533
	21st to end	Day	10% 9% 3 8% 5% 4 5% 5% 6% 7% 38%	5781
February	1st to 10th	Day	16% 12% 4 8% 5% 5% 5% 3 5% 6% 30%	1890
	11th to 20th	Day	15% 13% 3 9% 5% 5% 4 3 6% 6% 32%	1843
	21st to end	Day	11% 12% 4 8% 6% 4 4 4 5% 5% 36%	1657
March	1st to 10th	Day	23% 13% 3 13% 4 3 3 2 4 4 28%	4894
	11th to 20th	Day	19% 16% 4 8% 4 4 4 3 5% 6% 28%	5090
	21st to end	Day	28% 12% 4 8% 4 4 4 3 5% 5% 23%	5587
April	1st to 10th	Day	22% 14% 3 7% 5% 4 3 3 4 6% 28%	2435
	11th to 20th	Day	21% 11% 2 6% 5% 4 3 3 5% 6% 34%	2702
	21st to end	Day	23% 9% 3 7% 5% 4 4 3 5% 6% 32%	2730
May	1st to 10th	Day	29% 12% 3 6% 5% 5% 4 3 4 5% 24%	7639
	11th to 20th	Day	20% 9% 3 7% 5% 4 4 4 5% 7% 32%	8102
	21st to end	Day	22% 10% 3 7% 5% 4 4 3 5% 7% 30%	9109
June	1st to 10th	Day	23% 10% 3 7% 5% 5% 4 4 5% 7% 28%	3150
	11th to 20th	Day	21% 9% 3 6% 5% 4 3 3 5% 7% 34%	3150
	21st to end	Day	29% 8% 2 7% 4 4 3 3 6% 6% 28%	3150
July	1st to 10th	Day	16% 8% 3 7% 5% 5% 5% 4 6% 8% 32%	8880
	11th to 20th	Day	18% 8% 2 6% 4 4 4 4 5% 7% 38%	8880
	21st to end	Day	17% 7% 2 6% 4 4 4 4 6% 7% 39%	8408
August	1st to 10th	Day	21% 9% 3 7% 4 4 4 3 5% 7% 33%	6015
	11th to 20th	Day	17% 8% 3 7% 4 5% 5% 4 6% 8% 33%	5953
	21st to end	Day	16% 6% 2 5% 4 3 4 3 5% 8% 42%	6553
September	1st to 10th	Day	15% 7% 2 6% 4 4 4 3 5% 7% 42%	2517
	11th to 20th	Day	17% 6% 2 5% 3 3 4 3 4 6% 47%	2310
	21st to end	Day	21% 5% 2 4 3 3 3 2 5% 6% 44%	2310
October	1st to 10th	Day	17% 7% 2 6% 5% 3 4 3 5% 6% 41%	2116
	11th to 20th	Day	21% 9% 2 6% 4 4 4 3 5% 6% 36%	2030
	21st to end	Day	20% 10% 4 7% 5% 4 4 3 5% 6% 32%	2113
November	1st to 10th	Day	23% 10% 2 6% 5% 4 3 2 4 6% 35%	1762
	11th to 20th	Day	20% 10% 3 6% 4 3 5% 3 4 7% 35%	1680
	21st to end	Day	21% 13% 4 7% 5% 4 5% 4 4 5% 30%	1680
December	1st to 10th	Day	21% 10% 3 9% 5% 3 3 3 4 6% 33%	2690
	11th to 20th	Day	24% 12% 3 7% 4 3 2 2 3 4 35%	2800
	21st to end	Day	20% 11% 3 6% 4 4 4 4 4 7% 34%	3553
January	1st to 10th	Night	14% 14% 4 8% 5% 5% 4 3 5% 5% 32%	8831
	11th to 20th	Night	21% 13% 4 9% 5% 4 4 3 5% 5% 28%	8340
	21st to end	Night	10% 13% 3 6% 4 4 4 3 5% 7% 40%	8400
February	1st to 10th	Night	17% 11% 3 8% 5% 4 4 5% 5% 6% 32%	2730
	11th to 20th	Night	16% 12% 4 9% 5% 5% 5% 4 5% 5% 31%	2663
	21st to end	Night	14% 12% 4 8% 6% 4 5% 4 5% 6% 34%	2145
March	1st to 10th	Night	25% 13% 4 8% 4 5% 4 3 3 4 26%	5164
	11th to 20th	Night	21% 15% 4 9% 4 5% 4 3 5% 5% 26%	5089
	21st to end	Night	31% 12% 3 6% 4 4 4 3 3 4 28%	5587
April	1st to 10th	Night	23% 12% 3 7% 5% 4 4 3 4 3 29%	2179
	11th to 20th	Night	25% 10% 2 6% 4 4 4 3 4 5% 33%	1868
	21st to end	Night	24% 9% 3 7% 4 3 4 4 6% 6% 30%	1890
May	1st to 10th	Night	29% 11% 3 8% 4 4 4 4 3 5% 25%	5259
	11th to 20th	Night	22% 11% 2 6% 4 4 4 3 5% 6% 32%	4782
	21st to end	Night	19% 13% 4 9% 5% 4 4 3 5% 6% 30%	5147
June	1st to 10th	Night	25% 11% 2 7% 4 4 4 3 5% 6% 27%	1475
	11th to 20th	Night	22% 9% 3 7% 5% 4 3 3 5% 5% 32%	1470
	21st to end	Night	30% 9% 3 6% 5% 4 5% 2 4 5% 26%	1470
July	1st to 10th	Night	21% 10% 3 8% 5% 5% 5% 5% 5% 6% 27%	4110
	11th to 20th	Night	20% 12% 3 7% 4 4 4 3 5% 7% 32%	4110
	21st to end	Night	19% 8% 2 6% 3 4 4 3 5% 7% 38%	5593
August	1st to 10th	Night	25% 11% 3 7% 5% 4 4 3 5% 5% 28%	4135
	11th to 20th	Night	18% 11% 3 8% 4 4 4 3 5% 7% 33%	4092
	21st to end	Night	20% 10% 3 5% 4 3 3 3 4 6% 38%	4571
September	1st to 10th	Night	18% 7% 2 6% 4 4 4 3 6% 7% 40%	2100
	11th to 20th	Night	19% 6% 2 6% 3 3 3 3 5% 6% 44%	2310
	21st to end	Night	22% 6% 2 5% 4 3 3 4 4 6% 41%	2310
October	1st to 10th	Night	20% 6% 2 5% 4 4 3 3 5% 7% 41%	2503
	11th to 20th	Night	18% 9% 3 7% 4 4 4 3 4 5% 38%	2437
	21st to end	Night	22% 11% 3 7% 4 4 3 4 4 5% 33%	2725
November	1st to 10th	Night	22% 8% 3 6% 4 4 4 3 5% 6% 36%	2755
	11th to 20th	Night	21% 10% 3 7% 4 4 4 4 5% 6% 33%	2940
	21st to end	Night	21% 11% 3 7% 5% 4 4 3 5% 6% 32%	2940
December	1st to 10th	Night	18% 12% 4 8% 4 4 3 3 4 5% 35%	4720
	11th to 20th	Night	24% 11% 3 7% 4 3 3 3 4 4 36%	5624
	21st to end	Night	20% 13% 4 8% 4 3 3 3 5% 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	58% 5% 11% 17% 9% 1	4094
	11th to 20th	Day	60% 4 7% 20% 9% 1	4563
	21st to end	Day	45% 4 9% 21% 19% 3	5781
February	1st to 10th	Day	54% 4 10% 20% 10% 2	1890
	11th to 20th	Day	53% 3 11% 19% 12% 2	1851
	21st to end	Day	49% 5% 10% 23% 11% 3	1657
March	1st to 10th	Day	61% 3 7% 15% 11% 3	4898
	11th to 20th	Day	56% 5% 12% 17% 8% 1	5090
	21st to end	Day	63% 4 4 15% 12% 2	5587
April	1st to 10th	Day	58% 3 8% 15% 13% 3	2435
	11th to 20th	Day	52% 4 8% 23% 13% 1	2702
	21st to end	Day	53% 4 10% 18% 12% 4	2730
May	1st to 10th	Day	64% 4 8% 17% 7%	7651
	11th to 20th	Day	51% 5% 13% 22% 8% 1	8106
	21st to end	Day	56% 4 9% 17% 13% 1	9110
June	1st to 10th	Day	56% 5% 10% 20% 8% 1	3150
	11th to 20th	Day	51% 5% 10% 22% 11% 2	3150
	21st to end	Day	57% 5% 11% 16% 10% 1	3150
July	1st to 10th	Day	49% 7% 14% 19% 11%	8805
	11th to 20th	Day	45% 6% 14% 25% 9% 1	8799
	21st to end	Day	45% 5% 13% 27% 10%	8223
August	1st to 10th	Day	52% 6% 14% 20% 8% 1	6002
	11th to 20th	Day	47% 6% 17% 23% 6%	5992
	21st to end	Day	39% 5% 15% 24% 14% 1	6553
September	1st to 10th	Day	42% 4 11% 26% 15% 1	2517
	11th to 20th	Day	41% 4 10% 27% 16% 2	2310
	21st to end	Day	43% 4 8% 27% 17% 2	2310
October	1st to 10th	Day	45% 6% 11% 28% 11%	3376
	11th to 20th	Day	46% 4 9% 31% 10%	3270
	21st to end	Day	42% 5% 16% 21% 17%	3389
November	1st to 10th	Day	53% 4 10% 22% 11% 1	1762
	11th to 20th	Day	49% 5% 12% 19% 14% 2	1680
	21st to end	Day	57% 4 11% 20% 7%	1680
December	1st to 10th	Day	54% 4 13% 22% 6%	2690
	11th to 20th	Day	56% 3 9% 17% 12% 3	2800
	21st to end	Day	51% 4 10% 20% 13% 2	3553
January	1st to 10th	Night	53% 5% 9% 24% 9% 1	8831
	11th to 20th	Night	59% 4 9% 20% 8% 1	8385
	21st to end	Night	44% 3 7% 24% 17% 4	8400
February	1st to 10th	Night	52% 4 11% 18% 14% 2	2730
	11th to 20th	Night	54% 4 9% 20% 11% 2	2666
	21st to end	Night	51% 5% 7% 21% 13% 3	2145
March	1st to 10th	Night	62% 3 5% 13% 13% 4	5173
	11th to 20th	Night	60% 4 12% 15% 8% 1	5090
	21st to end	Night	62% 3 4 17% 12% 2	5587
April	1st to 10th	Night	59% 3 7% 15% 12% 4	2179
	11th to 20th	Night	54% 3 8% 21% 13% 1	1868
	21st to end	Night	54% 4 8% 19% 13% 2	1890
May	1st to 10th	Night	64% 4 10% 15% 7% 1	5265
	11th to 20th	Night	54% 4 12% 21% 7% 2	4783
	21st to end	Night	56% 4 11% 17% 10% 2	5148
June	1st to 10th	Night	58% 4 10% 20% 8% 1	1475
	11th to 20th	Night	53% 5% 11% 22% 8% 1	1470
	21st to end	Night	61% 4 7% 17% 9% 1	1470
July	1st to 10th	Night	58% 6% 10% 16% 10%	4075
	11th to 20th	Night	53% 5% 10% 23% 9%	4068
	21st to end	Night	46% 5% 12% 23% 13% 1	5464
August	1st to 10th	Night	59% 5% 11% 17% 7% 1	4123
	11th to 20th	Night	52% 5% 17% 20% 5%	4119
	21st to end	Night	48% 5% 11% 22% 13% 1	4570
September	1st to 10th	Night	44% 4 10% 27% 14% 1	2100
	11th to 20th	Night	42% 3 11% 26% 17% 1	2310
	21st to end	Night	45% 4 8% 26% 15% 2	2310
October	1st to 10th	Night	45% 4 12% 24% 14% 1	4023
	11th to 20th	Night	41% 4 10% 27% 17%	3936
	21st to end	Night	46% 4 12% 23% 14% 1	4399
November	1st to 10th	Night	50% 4 12% 21% 12% 1	2755
	11th to 20th	Night	53% 4 9% 20% 12% 1	2940
	21st to end	Night	53% 5% 13% 18% 10% 1	2940
December	1st to 10th	Night	50% 5% 10% 25% 9%	4720
	11th to 20th	Night	54% 4 6% 20% 14% 2	5625
	21st to end	Night	55% 4 9% 18% 12% 3	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	31% 28% 30% 10%	220
	11th to 20th	Day	41% 20% 28% 9% 2	221
	21st to end	Day	22% 26% 35% 14% 3	473
February	1st to 10th	Day	30% 24% 27% 14% 4	430
	11th to 20th	Day	28% 29% 28% 12% 3	426
	21st to end	Day	26% 29% 30% 13% 2	408
March	1st to 10th	Day	30% 26% 32% 9% 2	540
	11th to 20th	Day	31% 24% 30% 11% 3 1	540
	21st to end	Day	39% 21% 26% 8% 4 1	594
April	1st to 10th	Day	39% 29% 22% 7% 2	540
	11th to 20th	Day	37% 25% 25% 10% 4	532
	21st to end	Day	32% 22% 29% 13% 4 1	540
May	1st to 10th	Day	36% 20% 30% 10% 3	543
	11th to 20th	Day	28% 19% 30% 18% 4 1	732
	21st to end	Day	33% 18% 29% 16% 4 1	845
June	1st to 10th	Day	31% 17% 29% 18% 5%	780
	11th to 20th	Day	29% 16% 29% 21% 5% 1	780
	21st to end	Day	34% 13% 28% 18% 6% 1	780
July	1st to 10th	Day	28% 11% 34% 21% 7% 1	770
	11th to 20th	Day	29% 10% 31% 22% 7% 2	768
	21st to end	Day	26% 13% 37% 18% 6% 1	637
August	1st to 10th	Day	22% 11% 34% 26% 5% 1	566
	11th to 20th	Day	24% 11% 36% 21% 7% 1	559
	21st to end	Day	22% 15% 30% 24% 8% 2	627
September	1st to 10th	Day	19% 15% 38% 20% 6% 2	570
	11th to 20th	Day	25% 15% 30% 20% 7% 3	570
	21st to end	Day	24% 16% 34% 18% 6% 2	570
October	1st to 10th	Day	24% 15% 29% 20% 10% 2	459
	11th to 20th	Day	26% 18% 28% 19% 7% 2	429
	21st to end	Day	28% 21% 32% 15% 4 1	462
November	1st to 10th	Day	32% 18% 31% 13% 4 1	425
	11th to 20th	Day	33% 22% 26% 14% 4	430
	21st to end	Day	35% 24% 28% 9% 3	430
December	1st to 10th	Day	36% 20% 28% 14% 3	430
	11th to 20th	Day	37% 28% 25% 8% 2	293
	21st to end	Day	35% 26% 26% 11% 2	242
January	1st to 10th	Night	27% 24% 28% 17% 4	950
	11th to 20th	Night	31% 20% 26% 18% 4	862
	21st to end	Night	22% 26% 33% 16% 4	924
February	1st to 10th	Night	28% 22% 29% 18% 3	840
	11th to 20th	Night	27% 25% 28% 17% 3	823
	21st to end	Night	24% 22% 30% 21% 3 1	692
March	1st to 10th	Night	27% 21% 34% 17% 1	840
	11th to 20th	Night	27% 18% 31% 20% 4	840
	21st to end	Night	28% 20% 30% 16% 5% 1	924
April	1st to 10th	Night	33% 19% 30% 16% 2	723
	11th to 20th	Night	32% 14% 32% 17% 4	624
	21st to end	Night	29% 16% 29% 21% 5%	630
May	1st to 10th	Night	31% 13% 29% 21% 5%	630
	11th to 20th	Night	31% 12% 32% 20% 5%	622
	21st to end	Night	28% 15% 34% 18% 4	682
June	1st to 10th	Night	35% 6% 27% 27% 5%	425
	11th to 20th	Night	28% 8% 30% 29% 5%	420
	21st to end	Night	35% 6% 23% 30% 6%	420
July	1st to 10th	Night	28% 6% 27% 31% 8%	410
	11th to 20th	Night	30% 6% 23% 32% 8%	408
	21st to end	Night	27% 5% 29% 29% 9%	654
August	1st to 10th	Night	23% 5% 29% 33% 10% 1	628
	11th to 20th	Night	27% 7% 24% 31% 10%	622
	21st to end	Night	23% 7% 26% 30% 13% 1	693
September	1st to 10th	Night	23% 7% 31% 29% 9% 1	630
	11th to 20th	Night	24% 10% 23% 28% 14% 1	840
	21st to end	Night	26% 10% 28% 24% 11% 1	840
October	1st to 10th	Night	26% 10% 25% 27% 10% 1	840
	11th to 20th	Night	24% 16% 28% 21% 10% 1	813
	21st to end	Night	30% 18% 27% 22% 3	880
November	1st to 10th	Night	30% 17% 27% 18% 7% 1	867
	11th to 20th	Night	29% 21% 25% 19% 6% 1	950
	21st to end	Night	31% 21% 24% 18% 4 1	950
December	1st to 10th	Night	33% 19% 27% 17% 3	950
	11th to 20th	Night	33% 26% 26% 12% 2	950
	21st to end	Night	31% 24% 25% 16% 4	1045

Page generated at 2026-10-11 06:06:29. Version ac07

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