Carberry
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Carberry clear sky chart from 2005-11-06 to 2025-02-21.

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	11% 8% 3 8% 6% 5% 5% 4 6% 8% 36%	112130
	Night	9% 9% 4 10% 6% 5% 5% 4 6% 7% 35%	115186
Transparency	Day	45% 7% 16% 24% 7%	111882
	Night	46% 6% 15% 23% 9% 1	115081
Seeing	Day	14% 9% 31% 28% 15% 3	16569
	Night	14% 7% 32% 33% 12% 1	26703

By Month

Percentage Cloud Cover NW (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	4 15% 5% 14% 10% 7% 5% 5% 8% 9% 17%	3179
	11th to 20th	Day	4 9% 4 13% 8% 9% 9% 7% 9% 9% 20%	3412
	21st to end	Day	6% 11% 5% 14% 7% 6% 5% 5% 5% 6% 30%	4004
February	1st to 10th	Day	9% 12% 5% 12% 9% 7% 6% 4 7% 6% 23%	1605
	11th to 20th	Day	5% 10% 4 9% 9% 7% 7% 5% 7% 7% 29%	1773
	21st to end	Day	7% 11% 5% 11% 7% 7% 7% 4 6% 7% 28%	1570
March	1st to 10th	Day	11% 12% 4 9% 8% 7% 5% 4 5% 8% 27%	3130
	11th to 20th	Day	9% 12% 5% 10% 8% 6% 6% 5% 7% 8% 25%	3431
	21st to end	Day	8% 9% 6% 13% 7% 6% 4 3 6% 6% 32%	3893
April	1st to 10th	Day	9% 12% 3 8% 4 5% 5% 4 6% 8% 36%	2304
	11th to 20th	Day	13% 12% 4 10% 5% 5% 5% 3 5% 6% 31%	2442
	21st to end	Day	15% 8% 3 8% 5% 5% 5% 4 5% 6% 36%	2470
May	1st to 10th	Day	21% 9% 3 6% 3 4 3 3 5% 7% 34%	4226
	11th to 20th	Day	21% 8% 3 7% 5% 5% 4 4 6% 6% 31%	4660
	21st to end	Day	18% 7% 2 7% 4 5% 5% 4 6% 8% 35%	5173
June	1st to 10th	Day	14% 7% 2 7% 5% 4 5% 5% 7% 8% 36%	2850
	11th to 20th	Day	17% 6% 3 7% 6% 5% 5% 4 6% 7% 35%	2850
	21st to end	Day	12% 6% 2 6% 5% 6% 5% 5% 8% 8% 36%	2850
July	1st to 10th	Day	9% 4 1 5% 5% 5% 7% 6% 8% 11% 39%	4750
	11th to 20th	Day	7% 5% 2 5% 4 5% 5% 4 7% 9% 49%	4750
	21st to end	Day	5% 4 1 5% 4 4 5% 4 8% 11% 50%	4879
August	1st to 10th	Day	9% 6% 2 6% 4 4 5% 4 7% 9% 44%	4412
	11th to 20th	Day	10% 5% 2 5% 3 4 4 4 6% 10% 47%	4050
	21st to end	Day	10% 6% 2 5% 3 4 4 4 6% 8% 47%	4532
September	1st to 10th	Day	10% 4 2 6% 4 4 4 3 5% 7% 51%	2323
	11th to 20th	Day	15% 6% 2 6% 4 4 4 3 5% 7% 43%	2090
	21st to end	Day	16% 7% 2 6% 4 3 4 3 6% 7% 44%	2090
October	1st to 10th	Day	13% 8% 3 6% 3 4 3 3 4 6% 48%	3352
	11th to 20th	Day	9% 8% 3 7% 5% 4 4 3 5% 9% 43%	2904
	21st to end	Day	13% 12% 4 8% 4 4 4 3 5% 7% 35%	3091
November	1st to 10th	Day	18% 13% 6% 9% 5% 4 3 3 4 5% 30%	1698
	11th to 20th	Day	8% 16% 5% 12% 6% 4 4 4 5% 7% 29%	1560
	21st to end	Day	11% 12% 5% 11% 8% 5% 4 4 5% 7% 28%	1400
December	1st to 10th	Day	9% 13% 6% 17% 10% 11% 7% 4 4 5% 15%	2290
	11th to 20th	Day	8% 13% 5% 13% 8% 6% 5% 5% 7% 8% 22%	2639
	21st to end	Day	5% 10% 4 16% 8% 6% 5% 3 5% 6% 32%	3498
January	1st to 10th	Night	5% 11% 5% 17% 9% 8% 6% 4 6% 9% 20%	6787
	11th to 20th	Night	5% 11% 5% 13% 8% 7% 9% 7% 9% 8% 19%	6503
	21st to end	Night	7% 13% 7% 16% 7% 5% 5% 4 5% 7% 24%	6974
February	1st to 10th	Night	8% 12% 5% 11% 8% 6% 6% 4 5% 6% 28%	2793
	11th to 20th	Night	6% 9% 3 8% 6% 6% 7% 5% 7% 8% 35%	2533
	21st to end	Night	7% 11% 4 8% 7% 5% 5% 4 6% 8% 34%	1884
March	1st to 10th	Night	10% 11% 4 10% 6% 5% 5% 5% 7% 7% 29%	3734
	11th to 20th	Night	7% 11% 4 7% 4 4 5% 4 5% 8% 41%	3527
	21st to end	Night	7% 10% 4 11% 7% 6% 5% 4 6% 6% 34%	3739
April	1st to 10th	Night	7% 7% 3 7% 5% 4 6% 4 7% 8% 42%	1876
	11th to 20th	Night	15% 13% 4 9% 5% 3 4 3 5% 7% 32%	1689
	21st to end	Night	12% 9% 4 7% 5% 5% 5% 4 5% 6% 37%	1710
May	1st to 10th	Night	20% 8% 3 5% 5% 4 4 3 5% 6% 37%	2740
	11th to 20th	Night	16% 7% 2 7% 4 4 4 4 5% 6% 42%	2244
	21st to end	Night	18% 7% 2 5% 4 4 4 3 5% 7% 42%	2414
June	1st to 10th	Night	13% 5% 2 6% 4 4 4 4 7% 8% 44%	1330
	11th to 20th	Night	13% 5% 2 7% 4 5% 4 3 5% 8% 43%	1330
	21st to end	Night	10% 5% 2 5% 4 5% 5% 5% 7% 10% 42%	1330
July	1st to 10th	Night	8% 3 1 5% 3 4 4 5% 7% 11% 48%	2220
	11th to 20th	Night	6% 3 1 4 3 4 3 4 5% 8% 58%	2220
	21st to end	Night	4 4 1 4 4 3 4 4 5% 10% 56%	2682
August	1st to 10th	Night	5% 4 2 6% 4 4 5% 5% 6% 9% 50%	2528
	11th to 20th	Night	6% 4 2 5% 4 4 6% 4 7% 9% 50%	2788
	21st to end	Night	10% 6% 2 5% 3 4 3 3 5% 7% 53%	3135
September	1st to 10th	Night	7% 4 2 5% 3 4 4 3 5% 8% 54%	1853
	11th to 20th	Night	13% 5% 2 6% 4 3 4 3 6% 8% 48%	2090
	21st to end	Night	15% 7% 2 7% 4 3 3 3 4 8% 44%	2090
October	1st to 10th	Night	12% 7% 2 5% 4 3 4 3 5% 7% 48%	3576
	11th to 20th	Night	10% 6% 2 6% 4 4 5% 4 6% 8% 45%	4019
	21st to end	Night	7% 9% 3 7% 5% 5% 5% 4 6% 7% 43%	4467
November	1st to 10th	Night	12% 12% 4 9% 6% 5% 4 4 6% 6% 32%	2598
	11th to 20th	Night	10% 14% 6% 11% 6% 4 4 3 5% 6% 29%	2835
	21st to end	Night	10% 13% 5% 12% 6% 4 5% 3 4 6% 32%	3000
December	1st to 10th	Night	9% 13% 5% 16% 10% 8% 6% 4 5% 5% 19%	4900
	11th to 20th	Night	9% 13% 5% 12% 7% 6% 6% 4 6% 7% 25%	5568
	21st to end	Night	6% 8% 4 13% 9% 7% 7% 5% 6% 7% 30%	7480

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	59% 7% 14% 16% 4	3179
	11th to 20th	Day	56% 6% 11% 18% 7%	3435
	21st to end	Day	53% 5% 16% 21% 4	4004
February	1st to 10th	Day	58% 7% 11% 16% 7%	1605
	11th to 20th	Day	48% 9% 14% 20% 9%	1782
	21st to end	Day	53% 7% 14% 18% 7%	1570
March	1st to 10th	Day	50% 10% 18% 17% 4	3130
	11th to 20th	Day	53% 9% 14% 20% 5%	3433
	21st to end	Day	49% 8% 15% 22% 6%	3893
April	1st to 10th	Day	44% 6% 16% 25% 9% 1	2304
	11th to 20th	Day	53% 6% 12% 18% 10% 1	2442
	21st to end	Day	47% 7% 16% 21% 8% 1	2470
May	1st to 10th	Day	47% 7% 16% 22% 8% 1	4226
	11th to 20th	Day	50% 8% 11% 21% 9% 1	4664
	21st to end	Day	44% 9% 14% 25% 7% 1	5173
June	1st to 10th	Day	42% 9% 17% 21% 10% 1	2850
	11th to 20th	Day	47% 8% 16% 18% 10% 1	2850
	21st to end	Day	40% 10% 20% 23% 5% 1	2850
July	1st to 10th	Day	36% 7% 28% 24% 5%	4676
	11th to 20th	Day	31% 6% 20% 36% 7%	4669
	21st to end	Day	28% 5% 26% 33% 8%	4725
August	1st to 10th	Day	36% 5% 19% 29% 10%	4396
	11th to 20th	Day	32% 6% 21% 35% 6%	4089
	21st to end	Day	35% 4 21% 31% 8%	4531
September	1st to 10th	Day	33% 6% 18% 31% 10% 2	2323
	11th to 20th	Day	40% 7% 17% 26% 9% 1	2090
	21st to end	Day	39% 6% 15% 30% 10%	2090
October	1st to 10th	Day	39% 3 11% 37% 8%	3352
	11th to 20th	Day	40% 4 12% 34% 10%	2904
	21st to end	Day	49% 5% 11% 26% 9%	3091
November	1st to 10th	Day	57% 6% 12% 18% 7% 1	1698
	11th to 20th	Day	55% 6% 16% 17% 6%	1560
	21st to end	Day	55% 8% 17% 16% 5%	1400
December	1st to 10th	Day	71% 5% 13% 8% 2	2290
	11th to 20th	Day	57% 6% 17% 14% 6%	2640
	21st to end	Day	53% 4 12% 20% 11% 1	3498
January	1st to 10th	Night	59% 8% 10% 19% 4	6787
	11th to 20th	Night	58% 6% 12% 18% 6%	6542
	21st to end	Night	59% 6% 13% 18% 4	6974
February	1st to 10th	Night	54% 7% 13% 18% 8% 1	2793
	11th to 20th	Night	43% 7% 15% 23% 11% 1	2534
	21st to end	Night	46% 7% 14% 23% 10%	1884
March	1st to 10th	Night	48% 10% 16% 21% 5%	3734
	11th to 20th	Night	38% 8% 17% 25% 11% 1	3527
	21st to end	Night	47% 9% 14% 24% 7%	3739
April	1st to 10th	Night	37% 8% 13% 24% 17% 2	1876
	11th to 20th	Night	51% 6% 11% 19% 12% 1	1689
	21st to end	Night	46% 7% 14% 21% 11% 2	1710
May	1st to 10th	Night	45% 8% 13% 23% 11%	2740
	11th to 20th	Night	42% 7% 14% 23% 9% 5%	2244
	21st to end	Night	41% 7% 17% 24% 11% 1	2414
June	1st to 10th	Night	36% 7% 21% 24% 10% 2	1330
	11th to 20th	Night	38% 8% 16% 25% 11% 2	1330
	21st to end	Night	34% 12% 21% 26% 7% 1	1330
July	1st to 10th	Night	29% 7% 28% 27% 8% 1	2185
	11th to 20th	Night	24% 7% 18% 41% 10% 1	2178
	21st to end	Night	25% 4 25% 34% 11% 2	2597
August	1st to 10th	Night	30% 5% 18% 31% 14% 2	2520
	11th to 20th	Night	29% 5% 23% 33% 10% 1	2815
	21st to end	Night	32% 4 20% 34% 10% 1	3135
September	1st to 10th	Night	28% 6% 15% 34% 15% 2	1853
	11th to 20th	Night	35% 7% 18% 27% 13% 1	2090
	21st to end	Night	40% 6% 13% 30% 10% 2	2090
October	1st to 10th	Night	37% 4 13% 27% 16% 2	3576
	11th to 20th	Night	37% 4 13% 33% 12% 1	4019
	21st to end	Night	40% 4 14% 34% 7%	4467
November	1st to 10th	Night	51% 7% 15% 18% 7% 2	2598
	11th to 20th	Night	56% 8% 15% 15% 6% 1	2835
	21st to end	Night	54% 7% 17% 18% 5%	3000
December	1st to 10th	Night	67% 5% 12% 12% 3	4900
	11th to 20th	Night	58% 5% 15% 15% 6%	5566
	21st to end	Night	52% 6% 13% 18% 10% 1	7480

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	9% 8% 33% 30% 16% 4	300
	11th to 20th	Day	11% 10% 32% 35% 11% 2	300
	21st to end	Day	15% 8% 34% 28% 12% 2	330
February	1st to 10th	Day	14% 12% 40% 25% 8% 1	300
	11th to 20th	Day	7% 10% 39% 30% 13% 1	300
	21st to end	Day	5% 6% 40% 33% 14% 2	225
March	1st to 10th	Day	13% 10% 31% 35% 9% 2	270
	11th to 20th	Day	13% 11% 28% 31% 14% 2	270
	21st to end	Day	14% 9% 32% 29% 13% 3	338
April	1st to 10th	Day	14% 12% 35% 28% 10% 1	484
	11th to 20th	Day	18% 12% 33% 23% 12% 1	640
	21st to end	Day	15% 10% 34% 28% 12% 1	650
May	1st to 10th	Day	18% 10% 27% 29% 15% 2	653
	11th to 20th	Day	20% 9% 31% 23% 13% 4	675
	21st to end	Day	21% 9% 24% 27% 17% 3	734
June	1st to 10th	Day	15% 12% 29% 26% 13% 6%	680
	11th to 20th	Day	17% 11% 33% 24% 12% 3	680
	21st to end	Day	12% 8% 28% 31% 18% 4	680
July	1st to 10th	Day	9% 5% 26% 31% 20% 8%	671
	11th to 20th	Day	11% 7% 29% 27% 20% 5%	668
	21st to end	Day	6% 6% 26% 31% 23% 7%	739
August	1st to 10th	Day	9% 5% 28% 30% 21% 6%	676
	11th to 20th	Day	10% 5% 24% 29% 23% 8%	665
	21st to end	Day	15% 7% 25% 32% 18% 4	748
September	1st to 10th	Day	11% 9% 32% 30% 15% 3	533
	11th to 20th	Day	17% 7% 33% 30% 12% 1	300
	21st to end	Day	21% 11% 27% 29% 10% 2	300
October	1st to 10th	Day	24% 13% 24% 21% 15% 3	300
	11th to 20th	Day	16% 10% 37% 27% 10% 1	300
	21st to end	Day	23% 9% 36% 23% 7% 2	330
November	1st to 10th	Day	25% 10% 31% 22% 11% 1	300
	11th to 20th	Day	15% 11% 36% 29% 9% 1	300
	21st to end	Day	16% 10% 37% 30% 6%	300
December	1st to 10th	Day	14% 8% 38% 25% 12% 3	300
	11th to 20th	Day	16% 10% 39% 29% 5% 1	300
	21st to end	Day	10% 6% 36% 29% 15% 3	330
January	1st to 10th	Night	12% 9% 33% 33% 12% 1	1000
	11th to 20th	Night	15% 6% 37% 33% 8% 1	1000
	21st to end	Night	14% 8% 36% 34% 7% 1	1100
February	1st to 10th	Night	13% 8% 35% 32% 10% 1	1000
	11th to 20th	Night	10% 7% 32% 38% 11% 2	979
	21st to end	Night	11% 7% 32% 35% 14% 2	628
March	1st to 10th	Night	16% 6% 31% 32% 13% 3	760
	11th to 20th	Night	10% 9% 34% 33% 12% 1	604
	21st to end	Night	16% 6% 30% 32% 14% 2	627
April	1st to 10th	Night	8% 7% 37% 36% 10% 1	570
	11th to 20th	Night	19% 6% 32% 33% 9% 1	563
	21st to end	Night	13% 9% 34% 32% 12% 1	570
May	1st to 10th	Night	18% 6% 29% 36% 10% 1	570
	11th to 20th	Night	16% 8% 28% 35% 12%	561
	21st to end	Night	21% 8% 26% 32% 13%	617
June	1st to 10th	Night	14% 6% 32% 32% 15% 1	570
	11th to 20th	Night	13% 5% 33% 33% 15% 1	570
	21st to end	Night	12% 5% 24% 39% 18% 1	570
July	1st to 10th	Night	6% 3 24% 43% 23% 1	555
	11th to 20th	Night	7% 6% 26% 41% 19% 1	552
	21st to end	Night	7% 3 25% 42% 20% 3	624
August	1st to 10th	Night	7% 4 23% 44% 22% 1	567
	11th to 20th	Night	9% 4 22% 39% 23% 4	564
	21st to end	Night	13% 6% 24% 38% 18% 1	627
September	1st to 10th	Night	10% 3 31% 35% 18% 3	570
	11th to 20th	Night	15% 6% 28% 39% 12%	570
	21st to end	Night	18% 6% 29% 34% 11% 1	570
October	1st to 10th	Night	18% 8% 33% 30% 10% 1	627
	11th to 20th	Night	18% 9% 31% 31% 11%	898
	21st to end	Night	15% 11% 36% 28% 9% 1	1045
November	1st to 10th	Night	17% 9% 35% 28% 9% 1	975
	11th to 20th	Night	17% 8% 37% 27% 9% 2	1000
	21st to end	Night	16% 12% 37% 28% 7% 1	1000
December	1st to 10th	Night	12% 7% 37% 32% 10% 2	1000
	11th to 20th	Night	16% 11% 34% 28% 9% 2	1000
	21st to end	Night	17% 5% 32% 32% 13% 2	1100

Page generated at 2025-02-18 02:26:27. Version ac07

Copyright © 2025 Attilla Danko.