Takhini Hot Springs
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Takhini Hot Springs 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	8% 11% 4 11% 7% 6% 6% 5% 7% 8% 26%	156084
	Night	5% 11% 5% 12% 8% 7% 7% 5% 7% 8% 25%	144298
Transparency	Day	50% 9% 17% 17% 6%	155732
	Night	51% 10% 15% 16% 7% 1	144234
Seeing	Day	13% 11% 23% 28% 18% 6%	19800
	Night	9% 7% 24% 34% 22% 4	25715

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	1 8% 6% 17% 11% 10% 9% 6% 7% 6% 17%	2588
	11th to 20th	Day	2 9% 5% 13% 8% 8% 9% 6% 8% 9% 24%	3164
	21st to end	Day	3 15% 5% 13% 8% 5% 6% 4 6% 7% 29%	3890
February	1st to 10th	Day	2 12% 6% 13% 8% 10% 7% 5% 7% 8% 21%	1470
	11th to 20th	Day	3 15% 6% 12% 8% 8% 5% 5% 8% 8% 23%	1637
	21st to end	Day	1 12% 5% 15% 11% 8% 7% 5% 7% 6% 23%	1531
March	1st to 10th	Day	1 8% 4 13% 10% 10% 7% 5% 8% 6% 28%	4500
	11th to 20th	Day	2 12% 6% 14% 10% 8% 6% 5% 7% 8% 23%	4837
	21st to end	Day	2 8% 5% 12% 7% 6% 6% 5% 8% 10% 30%	6040
April	1st to 10th	Day	3 13% 5% 15% 7% 6% 7% 5% 7% 9% 24%	2552
	11th to 20th	Day	3 13% 5% 11% 8% 7% 6% 5% 6% 8% 28%	2906
	21st to end	Day	5% 13% 5% 13% 8% 6% 7% 5% 7% 7% 25%	2940
May	1st to 10th	Day	8% 19% 4 10% 6% 5% 5% 4 6% 7% 27%	9280
	11th to 20th	Day	6% 15% 4 12% 7% 7% 7% 5% 7% 7% 23%	9352
	21st to end	Day	6% 11% 3 9% 7% 7% 7% 5% 7% 8% 29%	10918
June	1st to 10th	Day	11% 11% 3 9% 7% 6% 7% 4 7% 8% 26%	3780
	11th to 20th	Day	13% 11% 4 11% 8% 6% 6% 4 6% 8% 23%	3780
	21st to end	Day	9% 9% 4 10% 9% 7% 7% 5% 8% 8% 24%	3780
July	1st to 10th	Day	11% 10% 4 10% 7% 7% 7% 5% 7% 8% 23%	10620
	11th to 20th	Day	12% 7% 3 8% 6% 6% 6% 5% 7% 8% 32%	10143
	21st to end	Day	11% 8% 3 9% 6% 6% 7% 6% 8% 9% 27%	10218
August	1st to 10th	Day	7% 5% 2 6% 5% 5% 5% 5% 7% 8% 44%	7251
	11th to 20th	Day	12% 8% 3 7% 4 4 4 5% 5% 8% 40%	6506
	21st to end	Day	18% 11% 3 9% 6% 5% 6% 4 7% 7% 24%	7082
September	1st to 10th	Day	15% 13% 3 10% 6% 5% 5% 4 6% 7% 25%	2572
	11th to 20th	Day	12% 10% 4 9% 6% 5% 6% 4 7% 7% 30%	2520
	21st to end	Day	12% 15% 4 10% 7% 6% 6% 5% 5% 7% 23%	2233
October	1st to 10th	Day	9% 16% 5% 12% 7% 7% 7% 5% 6% 7% 18%	3370
	11th to 20th	Day	8% 15% 6% 13% 6% 5% 5% 4 6% 9% 23%	2921
	21st to end	Day	8% 17% 6% 14% 7% 6% 6% 5% 7% 6% 17%	2825
November	1st to 10th	Day	5% 17% 7% 15% 10% 7% 8% 5% 5% 6% 15%	1442
	11th to 20th	Day	4 17% 8% 18% 14% 7% 5% 4 6% 5% 12%	1260
	21st to end	Day	2 14% 5% 16% 11% 9% 8% 7% 8% 6% 13%	1126
December	1st to 10th	Day	5% 13% 5% 13% 9% 7% 7% 6% 8% 9% 17%	1484
	11th to 20th	Day	2 9% 4 14% 12% 8% 10% 6% 8% 10% 18%	1542
	21st to end	Day	6% 12% 5% 14% 11% 10% 9% 7% 8% 7% 12%	2024
January	1st to 10th	Night	2 10% 5% 17% 12% 11% 10% 6% 7% 6% 15%	10364
	11th to 20th	Night	3 12% 5% 12% 7% 6% 6% 6% 9% 12% 22%	9734
	21st to end	Night	4 13% 5% 12% 8% 7% 6% 5% 6% 8% 26%	10276
February	1st to 10th	Night	4 11% 5% 13% 9% 8% 8% 5% 7% 7% 22%	3150
	11th to 20th	Night	2 12% 5% 15% 9% 8% 8% 5% 8% 7% 22%	2869
	21st to end	Night	3 12% 6% 12% 10% 6% 7% 6% 6% 7% 25%	2274
March	1st to 10th	Night	1 8% 3 13% 10% 11% 8% 6% 7% 8% 26%	5594
	11th to 20th	Night	3 11% 6% 14% 10% 8% 8% 5% 6% 7% 21%	5352
	21st to end	Night	2 9% 5% 14% 7% 6% 6% 4 7% 7% 31%	5153
April	1st to 10th	Night	2 11% 5% 12% 7% 6% 7% 6% 7% 9% 29%	2065
	11th to 20th	Night	2 11% 3 12% 6% 6% 7% 6% 6% 10% 31%	1663
	21st to end	Night	4 10% 3 8% 6% 6% 6% 5% 8% 9% 34%	1680
May	1st to 10th	Night	4 10% 3 8% 4 6% 7% 5% 7% 9% 37%	3636
	11th to 20th	Night	4 10% 4 10% 7% 5% 5% 5% 8% 10% 33%	3510
	21st to end	Night	5% 9% 3 7% 5% 6% 6% 5% 7% 9% 38%	3249
June	1st to 10th	Night	12% 7% 3 6% 7% 4 5% 5% 7% 9% 34%	840
	11th to 20th	Night	11% 10% 3 10% 7% 5% 7% 6% 8% 9% 24%	840
	21st to end	Night	8% 8% 2 8% 5% 6% 6% 7% 9% 11% 31%	840
July	1st to 10th	Night	9% 6% 3 8% 6% 7% 6% 6% 9% 9% 32%	2340
	11th to 20th	Night	6% 6% 2 7% 5% 6% 6% 5% 7% 10% 40%	2815
	21st to end	Night	14% 7% 3 8% 6% 5% 6% 6% 8% 9% 28%	3850
August	1st to 10th	Night	6% 3 2 6% 4 5% 5% 4 7% 9% 48%	2889
	11th to 20th	Night	10% 6% 2 6% 4 5% 5% 4 6% 10% 41%	3559
	21st to end	Night	15% 10% 3 9% 5% 6% 6% 5% 6% 6% 30%	4066
September	1st to 10th	Night	13% 7% 3 9% 7% 7% 6% 5% 7% 7% 29%	2045
	11th to 20th	Night	9% 9% 3 9% 5% 5% 5% 5% 6% 9% 36%	2100
	21st to end	Night	12% 14% 4 10% 7% 6% 5% 4 6% 7% 26%	2387
October	1st to 10th	Night	10% 15% 3 9% 5% 6% 6% 6% 8% 8% 24%	4040
	11th to 20th	Night	10% 16% 6% 14% 6% 5% 5% 4 5% 6% 24%	4278
	21st to end	Night	7% 17% 7% 13% 7% 5% 5% 4 6% 6% 21%	4975
November	1st to 10th	Night	5% 15% 7% 16% 10% 7% 7% 5% 7% 6% 16%	3076
	11th to 20th	Night	5% 17% 8% 16% 11% 7% 6% 6% 6% 6% 12%	3359
	21st to end	Night	3 13% 6% 15% 11% 8% 9% 6% 7% 7% 14%	3472
December	1st to 10th	Night	6% 15% 6% 13% 8% 7% 6% 5% 6% 7% 20%	5914
	11th to 20th	Night	2 10% 5% 16% 10% 8% 7% 6% 8% 8% 19%	6870
	21st to end	Night	4 16% 6% 16% 9% 8% 7% 6% 7% 7% 15%	9174

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% 11% 11% 9% 10% 1	2588
	11th to 20th	Day	50% 10% 13% 16% 11% 1	3180
	21st to end	Day	51% 9% 13% 17% 8% 2	3891
February	1st to 10th	Day	55% 10% 10% 13% 11% 1	1470
	11th to 20th	Day	53% 11% 13% 12% 10%	1645
	21st to end	Day	56% 9% 13% 16% 6%	1531
March	1st to 10th	Day	48% 8% 14% 18% 10% 1	4500
	11th to 20th	Day	51% 7% 17% 11% 11% 2	4837
	21st to end	Day	42% 11% 19% 20% 7% 1	6040
April	1st to 10th	Day	52% 10% 19% 14% 5%	2552
	11th to 20th	Day	50% 10% 14% 18% 8% 1	2906
	21st to end	Day	54% 9% 16% 16% 5%	2940
May	1st to 10th	Day	50% 9% 14% 17% 9%	9280
	11th to 20th	Day	53% 9% 12% 20% 6%	9355
	21st to end	Day	45% 6% 14% 18% 16%	10919
June	1st to 10th	Day	51% 8% 15% 19% 7% 1	3780
	11th to 20th	Day	56% 9% 15% 16% 3	3780
	21st to end	Day	52% 10% 17% 18% 3	3780
July	1st to 10th	Day	53% 9% 17% 17% 4	10531
	11th to 20th	Day	44% 9% 23% 22% 2	10047
	21st to end	Day	49% 11% 25% 14% 2	9997
August	1st to 10th	Day	35% 8% 20% 26% 10% 1	7232
	11th to 20th	Day	41% 7% 24% 23% 5%	6549
	21st to end	Day	55% 8% 17% 18% 2	7081
September	1st to 10th	Day	56% 10% 15% 16% 2	2572
	11th to 20th	Day	49% 9% 19% 20% 3	2520
	21st to end	Day	58% 8% 15% 16% 3	2233
October	1st to 10th	Day	60% 8% 12% 17% 3	3370
	11th to 20th	Day	56% 8% 18% 16% 2	2921
	21st to end	Day	61% 13% 17% 7% 1	2825
November	1st to 10th	Day	66% 11% 11% 9% 2	1442
	11th to 20th	Day	72% 7% 9% 10% 2	1260
	21st to end	Day	63% 12% 12% 8% 6%	1126
December	1st to 10th	Day	58% 12% 20% 6% 3	1484
	11th to 20th	Day	50% 15% 12% 14% 9%	1544
	21st to end	Day	62% 17% 8% 9% 5%	2024
January	1st to 10th	Night	64% 10% 8% 7% 11%	10365
	11th to 20th	Night	48% 9% 16% 15% 11% 2	9780
	21st to end	Night	52% 9% 13% 18% 5% 2	10276
February	1st to 10th	Night	56% 10% 11% 14% 8% 2	3150
	11th to 20th	Night	53% 13% 12% 13% 8% 1	2872
	21st to end	Night	53% 9% 14% 16% 7%	2274
March	1st to 10th	Night	49% 9% 12% 21% 8% 1	5594
	11th to 20th	Night	53% 8% 14% 16% 9% 1	5354
	21st to end	Night	45% 12% 18% 14% 11%	5153
April	1st to 10th	Night	47% 10% 19% 18% 5%	2065
	11th to 20th	Night	46% 9% 14% 22% 8%	1663
	21st to end	Night	39% 12% 18% 24% 8%	1680
May	1st to 10th	Night	35% 11% 18% 24% 12% 1	3633
	11th to 20th	Night	39% 11% 18% 21% 12% 1	3510
	21st to end	Night	36% 7% 14% 29% 14%	3253
June	1st to 10th	Night	43% 8% 16% 24% 8%	840
	11th to 20th	Night	49% 11% 18% 19% 3	840
	21st to end	Night	40% 12% 22% 22% 4	840
July	1st to 10th	Night	44% 10% 20% 23% 3	2320
	11th to 20th	Night	35% 10% 28% 24% 4	2788
	21st to end	Night	46% 10% 24% 16% 3	3766
August	1st to 10th	Night	30% 8% 20% 30% 11% 1	2883
	11th to 20th	Night	36% 8% 29% 22% 5%	3582
	21st to end	Night	50% 9% 16% 20% 5%	4066
September	1st to 10th	Night	49% 12% 19% 18% 2	2045
	11th to 20th	Night	42% 9% 21% 23% 4	2100
	21st to end	Night	55% 8% 15% 19% 4	2387
October	1st to 10th	Night	51% 9% 15% 21% 3	4040
	11th to 20th	Night	57% 9% 12% 19% 3	4278
	21st to end	Night	60% 11% 16% 11% 2	4975
November	1st to 10th	Night	63% 12% 13% 9% 3	3076
	11th to 20th	Night	69% 10% 10% 9% 2	3359
	21st to end	Night	62% 11% 12% 12% 4	3472
December	1st to 10th	Night	58% 11% 17% 11% 3	5914
	11th to 20th	Night	54% 12% 15% 12% 6% 1	6867
	21st to end	Night	60% 13% 9% 10% 7% 1	9174

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	4 4 19% 34% 32% 8%	110
	11th to 20th	Day	8% 6% 16% 38% 18% 14%	154
	21st to end	Day	7% 12% 18% 40% 15% 7%	247
February	1st to 10th	Day	9% 6% 22% 37% 19% 7%	430
	11th to 20th	Day	7% 10% 26% 34% 17% 7%	425
	21st to end	Day	7% 11% 26% 35% 16% 4	355
March	1st to 10th	Day	6% 9% 27% 33% 17% 9%	430
	11th to 20th	Day	6% 11% 30% 27% 20% 6%	430
	21st to end	Day	6% 9% 25% 28% 21% 10%	577
April	1st to 10th	Day	7% 13% 28% 30% 15% 5%	572
	11th to 20th	Day	9% 14% 26% 28% 18% 5%	740
	21st to end	Day	9% 18% 24% 29% 14% 4	750
May	1st to 10th	Day	18% 21% 27% 22% 8% 3	753
	11th to 20th	Day	13% 15% 25% 26% 14% 7%	775
	21st to end	Day	12% 13% 27% 27% 17% 5%	970
June	1st to 10th	Day	15% 10% 21% 28% 21% 4	990
	11th to 20th	Day	16% 9% 19% 27% 22% 6%	990
	21st to end	Day	11% 7% 17% 29% 26% 10%	990
July	1st to 10th	Day	15% 8% 18% 31% 22% 7%	976
	11th to 20th	Day	16% 9% 17% 28% 22% 8%	810
	21st to end	Day	16% 7% 20% 26% 24% 8%	849
August	1st to 10th	Day	13% 8% 21% 29% 20% 9%	776
	11th to 20th	Day	22% 13% 22% 24% 14% 5%	765
	21st to end	Day	21% 9% 24% 27% 14% 4	858
September	1st to 10th	Day	23% 13% 20% 20% 18% 7%	610
	11th to 20th	Day	15% 14% 21% 26% 17% 7%	570
	21st to end	Day	20% 17% 23% 21% 12% 7%	513
October	1st to 10th	Day	19% 18% 27% 21% 11% 4	450
	11th to 20th	Day	19% 16% 25% 23% 12% 5%	430
	21st to end	Day	13% 10% 24% 30% 18% 5%	457
November	1st to 10th	Day	11% 10% 30% 27% 18% 3	220
	11th to 20th	Day	8% 6% 19% 34% 27% 6%	220
	21st to end	Day	5% 5% 26% 34% 19% 12%	220
December	1st to 10th	Day	3 6% 20% 42% 20% 8%	157
	11th to 20th	Day	5% 6% 17% 35% 23% 13%	110
	21st to end	Day	4 5% 21% 36% 21% 12%	121
January	1st to 10th	Night	5% 4 23% 40% 24% 5%	1092
	11th to 20th	Night	9% 7% 30% 34% 17% 4	950
	21st to end	Night	8% 7% 29% 38% 16% 3	1045
February	1st to 10th	Night	7% 6% 24% 42% 19% 2	950
	11th to 20th	Night	5% 6% 32% 37% 16% 4	934
	21st to end	Night	6% 6% 24% 42% 18% 3	783
March	1st to 10th	Night	3 7% 25% 35% 25% 4	864
	11th to 20th	Night	5% 6% 24% 34% 25% 5%	751
	21st to end	Night	3 7% 17% 31% 36% 5%	693
April	1st to 10th	Night	4 7% 22% 35% 28% 4	630
	11th to 20th	Night	5% 7% 21% 32% 30% 5%	623
	21st to end	Night	7% 7% 19% 33% 30% 5%	630
May	1st to 10th	Night	8% 12% 23% 29% 24% 4	426
	11th to 20th	Night	9% 8% 22% 34% 26% 1	414
	21st to end	Night	7% 5% 21% 37% 28% 1	366
June	1st to 10th	Night	12% 5% 20% 39% 22% 2	210
	11th to 20th	Night	11% 4 21% 36% 25% 2	210
	21st to end	Night	9% 6% 17% 34% 31% 3	210
July	1st to 10th	Night	12% 4 21% 30% 29% 3	205
	11th to 20th	Night	10% 5% 17% 30% 33% 4	204
	21st to end	Night	12% 6% 22% 31% 25% 4	460
August	1st to 10th	Night	11% 7% 18% 35% 25% 4	469
	11th to 20th	Night	18% 8% 22% 28% 20% 4	624
	21st to end	Night	20% 4 20% 29% 22% 3	693
September	1st to 10th	Night	16% 9% 20% 29% 23% 3	630
	11th to 20th	Night	11% 7% 22% 30% 25% 3	630
	21st to end	Night	17% 12% 21% 31% 16% 3	817
October	1st to 10th	Night	18% 10% 25% 30% 16% 2	840
	11th to 20th	Night	18% 10% 22% 30% 17% 3	823
	21st to end	Night	12% 8% 25% 33% 19% 2	1001
November	1st to 10th	Night	9% 7% 26% 38% 17% 4	930
	11th to 20th	Night	10% 7% 21% 33% 23% 6%	950
	21st to end	Night	7% 8% 26% 35% 21% 4	1062
December	1st to 10th	Night	8% 7% 26% 37% 18% 4	1160
	11th to 20th	Night	8% 6% 23% 36% 22% 5%	1160
	21st to end	Night	9% 6% 24% 37% 19% 6%	1276

Page generated at 2026-10-11 01:06:31. Version ac07

Copyright © 2026 Attilla Danko.