Lakeland Provincial Park
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lakeland Provincial Park clear sky chart from 2005-11-06 to 2026-05-02.

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	9% 9% 4 9% 6% 5% 5% 4 6% 8% 34%	135183
	Night	8% 10% 4 10% 7% 6% 6% 4 6% 8% 32%	135935
Transparency	Day	47% 7% 17% 22% 7%	134879
	Night	49% 6% 16% 20% 8% 1	135820
Seeing	Day	15% 10% 29% 27% 14% 4	17627
	Night	13% 8% 29% 34% 14% 2	26594

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	5% 14% 7% 15% 10% 6% 7% 5% 5% 5% 21%	4125
	11th to 20th	Day	4 9% 4 11% 7% 6% 7% 7% 7% 8% 31%	4119
	21st to end	Day	5% 12% 6% 14% 11% 5% 5% 4 6% 7% 26%	4531
February	1st to 10th	Day	6% 13% 4 12% 8% 7% 5% 5% 7% 7% 24%	1670
	11th to 20th	Day	6% 11% 4 10% 9% 7% 8% 4 7% 8% 27%	1833
	21st to end	Day	4 11% 5% 12% 9% 8% 8% 5% 8% 8% 23%	1557
March	1st to 10th	Day	5% 9% 4 9% 7% 7% 8% 6% 8% 9% 29%	4608
	11th to 20th	Day	6% 9% 5% 12% 7% 6% 5% 4 7% 9% 30%	5109
	21st to end	Day	10% 15% 6% 13% 5% 4 4 3 5% 7% 25%	5607
April	1st to 10th	Day	7% 13% 4 8% 8% 6% 5% 4 6% 8% 31%	2660
	11th to 20th	Day	11% 13% 4 9% 6% 5% 5% 4 6% 7% 29%	2700
	21st to end	Day	13% 11% 4 8% 5% 5% 6% 4 7% 7% 30%	2803
May	1st to 10th	Day	12% 7% 3 8% 5% 5% 5% 4 6% 8% 36%	6636
	11th to 20th	Day	18% 11% 3 8% 6% 5% 5% 4 6% 6% 30%	6734
	21st to end	Day	10% 8% 3 8% 5% 5% 5% 5% 6% 8% 37%	7405
June	1st to 10th	Day	15% 8% 3 7% 6% 5% 6% 5% 7% 8% 31%	3137
	11th to 20th	Day	20% 10% 3 8% 6% 6% 5% 5% 6% 7% 26%	3220
	21st to end	Day	12% 7% 3 8% 6% 6% 6% 5% 6% 9% 33%	3395
July	1st to 10th	Day	7% 5% 2 6% 4 5% 6% 5% 8% 10% 42%	6789
	11th to 20th	Day	9% 5% 2 6% 4 5% 5% 4 6% 9% 44%	6780
	21st to end	Day	12% 6% 2 6% 4 5% 5% 5% 7% 9% 41%	7376
August	1st to 10th	Day	12% 7% 2 6% 4 4 5% 4 5% 6% 45%	4870
	11th to 20th	Day	9% 7% 2 6% 5% 4 5% 5% 7% 8% 41%	4237
	21st to end	Day	10% 5% 2 5% 4 4 5% 4 7% 9% 45%	4664
September	1st to 10th	Day	12% 6% 2 7% 5% 4 5% 4 6% 8% 41%	2535
	11th to 20th	Day	14% 8% 2 7% 4 5% 5% 4 5% 7% 40%	2255
	21st to end	Day	9% 7% 2 7% 5% 4 4 5% 6% 9% 43%	2200
October	1st to 10th	Day	9% 12% 4 8% 5% 4 5% 4 7% 8% 35%	3280
	11th to 20th	Day	12% 11% 4 7% 5% 5% 5% 4 6% 8% 33%	3075
	21st to end	Day	8% 14% 7% 11% 5% 5% 4 4 6% 7% 28%	2983
November	1st to 10th	Day	10% 16% 6% 10% 8% 5% 6% 4 4 6% 24%	1648
	11th to 20th	Day	7% 12% 5% 12% 8% 7% 5% 5% 7% 7% 24%	1547
	21st to end	Day	5% 12% 6% 14% 8% 5% 6% 5% 6% 7% 27%	1465
December	1st to 10th	Day	6% 14% 6% 15% 7% 7% 7% 5% 6% 8% 19%	2020
	11th to 20th	Day	8% 16% 7% 13% 8% 5% 5% 4 5% 6% 23%	2319
	21st to end	Day	3 9% 5% 14% 7% 7% 5% 4 7% 7% 32%	3291
January	1st to 10th	Night	6% 12% 5% 15% 10% 8% 7% 5% 7% 6% 19%	8768
	11th to 20th	Night	3 9% 3 10% 6% 7% 8% 5% 6% 9% 33%	8779
	21st to end	Night	6% 10% 5% 12% 8% 7% 7% 4 6% 7% 28%	9650
February	1st to 10th	Night	6% 11% 4 12% 7% 7% 7% 5% 6% 9% 26%	2970
	11th to 20th	Night	5% 11% 4 11% 7% 7% 5% 6% 6% 7% 31%	2674
	21st to end	Night	3 10% 4 10% 7% 8% 8% 6% 8% 9% 28%	2249
March	1st to 10th	Night	4 9% 5% 11% 7% 7% 7% 6% 8% 10% 27%	5499
	11th to 20th	Night	5% 10% 4 9% 7% 5% 7% 5% 7% 10% 32%	5110
	21st to end	Night	11% 16% 5% 12% 6% 4 4 4 5% 6% 26%	5610
April	1st to 10th	Night	8% 11% 4 8% 5% 5% 5% 4 7% 9% 35%	1957
	11th to 20th	Night	8% 10% 4 10% 6% 7% 6% 4 7% 7% 31%	1871
	21st to end	Night	12% 12% 4 8% 5% 5% 4 4 7% 7% 33%	1817
May	1st to 10th	Night	12% 7% 2 7% 5% 4 4 4 6% 8% 43%	3340
	11th to 20th	Night	16% 11% 4 8% 5% 5% 6% 4 6% 6% 29%	3159
	21st to end	Night	12% 8% 4 9% 5% 5% 5% 4 6% 8% 34%	3470
June	1st to 10th	Night	16% 7% 2 7% 5% 5% 8% 5% 6% 7% 32%	1260
	11th to 20th	Night	16% 12% 3 7% 6% 6% 5% 4 5% 8% 28%	1170
	21st to end	Night	10% 6% 2 7% 7% 5% 5% 4 8% 7% 39%	1000
July	1st to 10th	Night	6% 4 2 6% 4 4 6% 5% 8% 11% 44%	3165
	11th to 20th	Night	6% 5% 2 7% 4 4 5% 5% 7% 8% 46%	3180
	21st to end	Night	13% 5% 2 6% 4 4 4 4 6% 8% 43%	3467
August	1st to 10th	Night	10% 5% 2 7% 6% 4 5% 4 5% 7% 44%	2280
	11th to 20th	Night	10% 6% 2 7% 5% 5% 6% 5% 7% 10% 38%	2817
	21st to end	Night	9% 6% 1 6% 4 4 4 4 7% 9% 46%	3245
September	1st to 10th	Night	12% 6% 2 5% 3 4 5% 4 5% 8% 45%	1865
	11th to 20th	Night	12% 6% 2 6% 4 4 4 4 6% 7% 44%	2142
	21st to end	Night	10% 5% 2 6% 5% 4 4 4 7% 8% 45%	2200
October	1st to 10th	Night	8% 8% 3 7% 5% 5% 6% 4 7% 9% 38%	3910
	11th to 20th	Night	10% 9% 3 8% 5% 4 5% 4 7% 8% 39%	4070
	21st to end	Night	10% 10% 6% 11% 6% 5% 6% 5% 7% 7% 27%	4785
November	1st to 10th	Night	12% 16% 5% 11% 7% 5% 4 4 5% 6% 25%	2870
	11th to 20th	Night	8% 13% 5% 12% 8% 7% 6% 4 6% 6% 24%	3071
	21st to end	Night	5% 13% 5% 13% 8% 5% 5% 4 6% 7% 27%	3152
December	1st to 10th	Night	8% 15% 5% 15% 7% 6% 6% 5% 6% 6% 20%	5380
	11th to 20th	Night	6% 16% 6% 15% 10% 7% 6% 4 6% 6% 18%	6093
	21st to end	Night	3 10% 4 12% 9% 6% 5% 4 5% 7% 34%	7890

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% 4 9% 17% 6%	4125
	11th to 20th	Day	49% 7% 17% 15% 12% 1	4140
	21st to end	Day	57% 6% 19% 11% 7%	4531
February	1st to 10th	Day	56% 7% 14% 14% 10%	1670
	11th to 20th	Day	51% 7% 16% 17% 8%	1842
	21st to end	Day	54% 8% 15% 17% 6%	1557
March	1st to 10th	Day	47% 7% 21% 20% 6%	4608
	11th to 20th	Day	48% 6% 18% 21% 7%	5110
	21st to end	Day	57% 6% 10% 19% 8%	5607
April	1st to 10th	Day	49% 8% 15% 18% 9%	2660
	11th to 20th	Day	52% 6% 12% 19% 10% 1	2700
	21st to end	Day	49% 7% 13% 21% 8% 1	2803
May	1st to 10th	Day	45% 5% 12% 23% 14% 1	6636
	11th to 20th	Day	52% 6% 11% 22% 9%	6738
	21st to end	Day	41% 9% 18% 20% 11% 1	7406
June	1st to 10th	Day	47% 8% 14% 21% 9%	3137
	11th to 20th	Day	55% 9% 12% 18% 5%	3220
	21st to end	Day	44% 9% 18% 21% 6%	3395
July	1st to 10th	Day	36% 6% 24% 27% 7%	6715
	11th to 20th	Day	35% 5% 16% 32% 11%	6699
	21st to end	Day	38% 6% 22% 28% 6%	7169
August	1st to 10th	Day	39% 7% 21% 31% 2	4852
	11th to 20th	Day	38% 7% 25% 24% 6%	4277
	21st to end	Day	34% 6% 30% 26% 3	4663
September	1st to 10th	Day	39% 9% 20% 26% 6% 1	2535
	11th to 20th	Day	43% 6% 20% 26% 6%	2255
	21st to end	Day	37% 8% 20% 25% 9% 1	2200
October	1st to 10th	Day	46% 4 21% 25% 3	3280
	11th to 20th	Day	48% 5% 16% 26% 5%	3075
	21st to end	Day	53% 6% 20% 18% 2	2983
November	1st to 10th	Day	59% 7% 13% 16% 4	1648
	11th to 20th	Day	57% 7% 16% 16% 4	1547
	21st to end	Day	55% 9% 15% 16% 5%	1465
December	1st to 10th	Day	61% 8% 12% 14% 4	2020
	11th to 20th	Day	62% 5% 16% 15% 3	2320
	21st to end	Day	50% 5% 14% 25% 6% 1	3291
January	1st to 10th	Night	62% 5% 11% 13% 8%	8769
	11th to 20th	Night	46% 5% 17% 20% 12% 1	8820
	21st to end	Night	54% 6% 20% 13% 6%	9650
February	1st to 10th	Night	53% 7% 12% 18% 10%	2970
	11th to 20th	Night	49% 6% 13% 20% 11%	2675
	21st to end	Night	47% 8% 16% 19% 9% 1	2249
March	1st to 10th	Night	48% 6% 19% 19% 7%	5499
	11th to 20th	Night	45% 8% 16% 24% 7%	5110
	21st to end	Night	56% 7% 9% 17% 11%	5610
April	1st to 10th	Night	43% 7% 15% 24% 11%	1957
	11th to 20th	Night	48% 8% 12% 17% 11% 4	1871
	21st to end	Night	48% 5% 12% 23% 11% 2	1817
May	1st to 10th	Night	38% 6% 11% 25% 18% 2	3340
	11th to 20th	Night	52% 6% 11% 22% 9%	3159
	21st to end	Night	45% 8% 17% 21% 8% 1	3470
June	1st to 10th	Night	48% 9% 13% 19% 10% 1	1260
	11th to 20th	Night	53% 10% 13% 18% 6% 1	1170
	21st to end	Night	39% 12% 17% 23% 7% 1	1000
July	1st to 10th	Night	31% 7% 25% 27% 9% 1	3130
	11th to 20th	Night	33% 7% 15% 36% 9% 1	3138
	21st to end	Night	38% 6% 22% 29% 5%	3369
August	1st to 10th	Night	38% 6% 19% 34% 2	2273
	11th to 20th	Night	39% 7% 25% 22% 6%	2843
	21st to end	Night	35% 5% 26% 30% 4	3245
September	1st to 10th	Night	37% 7% 20% 27% 6% 2	1865
	11th to 20th	Night	37% 6% 20% 27% 9%	2142
	21st to end	Night	35% 6% 18% 29% 11% 2	2200
October	1st to 10th	Night	41% 5% 21% 25% 7%	3910
	11th to 20th	Night	42% 4 18% 29% 6%	4070
	21st to end	Night	53% 5% 19% 19% 4	4785
November	1st to 10th	Night	59% 6% 11% 19% 5%	2870
	11th to 20th	Night	58% 8% 15% 14% 5%	3071
	21st to end	Night	55% 7% 15% 17% 5%	3152
December	1st to 10th	Night	62% 7% 14% 13% 4 1	5380
	11th to 20th	Night	66% 6% 14% 11% 3	6091
	21st to end	Night	48% 5% 13% 21% 11% 1	7890

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	6% 11% 28% 36% 16% 3	220
	11th to 20th	Day	18% 11% 29% 30% 10% 3	220
	21st to end	Day	13% 12% 35% 28% 8% 4	242
February	1st to 10th	Day	10% 16% 31% 30% 11% 1	220
	11th to 20th	Day	10% 11% 33% 29% 14% 2	325
	21st to end	Day	8% 15% 34% 28% 10% 5%	273
March	1st to 10th	Day	12% 14% 39% 27% 8% 1	493
	11th to 20th	Day	11% 13% 40% 26% 8% 3	540
	21st to end	Day	17% 13% 34% 27% 9% 1	594
April	1st to 10th	Day	13% 14% 38% 25% 7% 3	540
	11th to 20th	Day	18% 12% 34% 21% 11% 3	532
	21st to end	Day	17% 13% 31% 25% 10% 3	613
May	1st to 10th	Day	14% 14% 25% 28% 15% 4	709
	11th to 20th	Day	14% 9% 25% 30% 17% 6%	725
	21st to end	Day	18% 6% 26% 27% 20% 4	789
June	1st to 10th	Day	20% 12% 28% 27% 10% 3	730
	11th to 20th	Day	22% 8% 25% 23% 16% 6%	750
	21st to end	Day	13% 6% 22% 31% 21% 7%	925
July	1st to 10th	Day	14% 6% 23% 32% 20% 5%	721
	11th to 20th	Day	12% 8% 23% 31% 20% 6%	718
	21st to end	Day	10% 6% 26% 28% 21% 8%	794
August	1st to 10th	Day	14% 6% 19% 30% 23% 8%	726
	11th to 20th	Day	12% 9% 26% 32% 16% 4	531
	21st to end	Day	12% 7% 26% 31% 19% 5%	583
September	1st to 10th	Day	15% 12% 28% 26% 15% 3	530
	11th to 20th	Day	19% 8% 28% 29% 14% 3	530
	21st to end	Day	15% 15% 32% 24% 12% 2	530
October	1st to 10th	Day	15% 11% 31% 27% 13% 3	340
	11th to 20th	Day	20% 12% 38% 22% 8% 1	330
	21st to end	Day	21% 15% 32% 20% 10% 2	363
November	1st to 10th	Day	22% 11% 33% 23% 9% 2	330
	11th to 20th	Day	13% 13% 48% 18% 7% 2	259
	21st to end	Day	11% 11% 40% 24% 9% 5%	220
December	1st to 10th	Day	10% 10% 38% 27% 12% 4	220
	11th to 20th	Day	10% 15% 38% 26% 10%	220
	21st to end	Day	10% 7% 30% 32% 16% 5%	242
January	1st to 10th	Night	12% 8% 33% 34% 12% 1	1050
	11th to 20th	Night	11% 10% 34% 34% 9% 2	1050
	21st to end	Night	15% 12% 35% 29% 8% 2	1155
February	1st to 10th	Night	12% 7% 29% 36% 14% 2	870
	11th to 20th	Night	11% 5% 36% 33% 14% 1	824
	21st to end	Night	8% 6% 28% 38% 18% 2	692
March	1st to 10th	Night	8% 8% 33% 37% 13% 1	840
	11th to 20th	Night	12% 7% 36% 32% 11% 2	840
	21st to end	Night	13% 9% 28% 35% 13% 2	924
April	1st to 10th	Night	11% 7% 32% 35% 13% 2	655
	11th to 20th	Night	13% 9% 33% 29% 15% 1	623
	21st to end	Night	17% 8% 27% 33% 14% 1	630
May	1st to 10th	Night	12% 9% 24% 35% 17% 3	477
	11th to 20th	Night	13% 7% 24% 37% 15% 4	394
	21st to end	Night	18% 5% 20% 35% 20% 2	433
June	1st to 10th	Night	20% 7% 23% 34% 16% 1	400
	11th to 20th	Night	21% 6% 21% 28% 21% 3	400
	21st to end	Night	12% 4 21% 34% 25% 4	400
July	1st to 10th	Night	12% 4 18% 39% 27% 1	390
	11th to 20th	Night	9% 5% 18% 41% 24% 2	388
	21st to end	Night	11% 4 17% 39% 24% 5%	438
August	1st to 10th	Night	11% 3 15% 36% 30% 6%	398
	11th to 20th	Night	12% 5% 21% 38% 23% 2	551
	21st to end	Night	12% 4 22% 38% 23% 2	660
September	1st to 10th	Night	16% 6% 22% 33% 22% 2	600
	11th to 20th	Night	15% 5% 21% 41% 18% 1	742
	21st to end	Night	13% 8% 29% 35% 14% 1	800
October	1st to 10th	Night	14% 8% 31% 35% 11% 2	800
	11th to 20th	Night	15% 6% 33% 33% 11% 3	800
	21st to end	Night	17% 11% 34% 29% 9% 1	990
November	1st to 10th	Night	20% 8% 31% 32% 8% 2	1025
	11th to 20th	Night	14% 10% 35% 28% 10% 3	1050
	21st to end	Night	10% 10% 38% 30% 11% 1	1050
December	1st to 10th	Night	13% 9% 32% 31% 12% 2	1050
	11th to 20th	Night	13% 11% 33% 32% 10% 2	1050
	21st to end	Night	9% 6% 31% 35% 16% 3	1155

Page generated at 2026-04-29 00:21:47. Version ac07

Copyright © 2026 Attilla Danko.