Pinetop
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Pinetop clear sky chart from 2005-11-06 to 2026-02-01.

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	3 5% 2 5% 4 4 4 3 5% 6% 59%	136492
	Night	2 5% 2 5% 3 3 4 3 5% 6% 62%	133052
Transparency	Day	25% 6% 7% 15% 28% 20%	131371
	Night	22% 5% 7% 16% 30% 20%	129176
Seeing	Day	12% 19% 28% 24% 13% 4	16290
	Night	8% 12% 24% 30% 21% 5%	26451

By Month

Percentage Cloud Cover SW (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	2 7% 3 6% 3 3 3 3 4 5% 62%	4188
	11th to 20th	Day	2 5% 2 4 3 2 3 3 3 4 69%	4190
	21st to end	Day	3 9% 4 6% 4 3 3 3 4 5% 57%	4609
February	1st to 10th	Day	2 10% 4 4 3 3 3 2 4 6% 59%	1800
	11th to 20th	Day	3 10% 3 5% 4 4 3 3 5% 5% 55%	1853
	21st to end	Day	3 10% 2 5% 3 4 3 2 5% 7% 56%	1788
March	1st to 10th	Day	2 7% 2 6% 4 3 3 3 4 6% 59%	4954
	11th to 20th	Day	2 13% 4 7% 4 4 4 3 5% 6% 49%	5000
	21st to end	Day	3 9% 4 7% 3 3 3 3 4 4 56%	5486
April	1st to 10th	Day	1 4 1 4 3 3 4 3 5% 7% 63%	2245
	11th to 20th	Day	2 4 1 4 3 3 3 3 4 4 68%	2371
	21st to end	Day	3 3 1 4 3 3 3 2 4 5% 67%	2400
May	1st to 10th	Day	3 3 1 4 3 4 4 3 4 5% 66%	5870
	11th to 20th	Day	1 2 1 3 3 3 4 3 5% 5% 70%	5841
	21st to end	Day	2 2 1 3 2 3 3 2 3 5% 75%	6423
June	1st to 10th	Day	1 2 1 2 3 3 4 3 5% 7% 69%	2600
	11th to 20th	Day	2 1 2 2 2 2 2 3 4 78%	2600
	21st to end	Day	2 4 1 5% 4 4 5% 4 5% 5% 61%	2600
July	1st to 10th	Day	3 3 1 5% 5% 5% 5% 4 5% 6% 58%	5879
	11th to 20th	Day	3 3 2 6% 7% 6% 8% 7% 9% 8% 41%	5880
	21st to end	Day	4 4 2 8% 6% 6% 7% 6% 8% 8% 40%	6401
August	1st to 10th	Day	4 3 2 7% 6% 6% 7% 6% 7% 8% 45%	5779
	11th to 20th	Day	4 3 2 7% 6% 8% 8% 6% 8% 8% 40%	5720
	21st to end	Day	4 4 1 6% 6% 6% 7% 5% 8% 9% 43%	5984
September	1st to 10th	Day	5% 5% 3 7% 5% 6% 6% 5% 6% 7% 44%	2320
	11th to 20th	Day	4 3 1 5% 4 4 4 4 5% 6% 60%	2200
	21st to end	Day	4 4 1 4 3 4 4 4 5% 6% 63%	2200
October	1st to 10th	Day	5% 4 2 5% 3 3 3 2 3 5% 65%	3337
	11th to 20th	Day	4 3 1 3 3 2 3 2 4 5% 70%	3250
	21st to end	Day	1 2 1 2 2 1 2 2 4 6% 78%	3548
November	1st to 10th	Day	2 3 1 3 2 2 2 2 4 5% 72%	2059
	11th to 20th	Day	2 3 1 4 3 3 3 3 5% 6% 68%	2079
	21st to end	Day	4 7% 2 6% 3 3 2 2 4 5% 61%	1890
December	1st to 10th	Day	3 4 1 4 2 3 2 3 4 4 71%	3040
	11th to 20th	Day	2 7% 3 6% 3 3 3 3 5% 8% 57%	3499
	21st to end	Day	2 7% 2 6% 3 4 3 3 4 5% 61%	4609
January	1st to 10th	Night	2 8% 3 7% 3 3 4 3 5% 6% 56%	5997
	11th to 20th	Night	2 4 1 3 2 2 2 2 3 4 74%	6010
	21st to end	Night	4 11% 4 7% 4 4 3 2 4 5% 52%	6611
February	1st to 10th	Night	2 9% 3 5% 3 3 2 3 5% 5% 62%	2600
	11th to 20th	Night	3 9% 2 6% 5% 4 4 4 4 5% 56%	2429
	21st to end	Night	3 7% 3 5% 3 4 3 3 5% 7% 57%	1840
March	1st to 10th	Night	2 10% 2 4 3 3 2 2 4 6% 61%	4940
	11th to 20th	Night	4 10% 3 6% 3 3 3 3 4 6% 55%	5000
	21st to end	Night	2 7% 3 5% 3 3 3 3 5% 6% 60%	5489
April	1st to 10th	Night	2 5% 1 3 4 3 3 3 5% 7% 64%	2155
	11th to 20th	Night	2 5% 1 4 2 2 2 2 4 6% 70%	1977
	21st to end	Night	2 2 1 2 2 2 2 2 4 6% 74%	2000
May	1st to 10th	Night	3 3 2 5% 3 2 3 2 4 5% 68%	4106
	11th to 20th	Night	1 2 1 3 2 2 2 2 4 5% 75%	4074
	21st to end	Night	1 1 1 2 2 2 2 2 3 4 81%	4474
June	1st to 10th	Night	2 3 1 4 2 3 3 3 5% 7% 68%	1800
	11th to 20th	Night	2 1 1 1 1 2 2 2 3 5% 81%	1800
	21st to end	Night	3 3 1 4 3 3 5% 3 5% 6% 64%	1800
July	1st to 10th	Night	2 3 1 5% 4 3 4 3 6% 7% 61%	4100
	11th to 20th	Night	3 4 2 8% 8% 8% 7% 7% 9% 10% 34%	4100
	21st to end	Night	3 4 2 7% 6% 6% 6% 5% 9% 12% 41%	4472
August	1st to 10th	Night	2 2 1 5% 5% 6% 6% 6% 8% 10% 49%	4033
	11th to 20th	Night	2 3 2 5% 4 5% 6% 6% 11% 13% 42%	4126
	21st to end	Night	3 4 2 7% 6% 6% 7% 7% 10% 10% 40%	4993
September	1st to 10th	Night	4 4 2 6% 4 5% 6% 4 7% 9% 50%	2075
	11th to 20th	Night	3 3 1 4 2 3 4 4 4 6% 66%	2200
	21st to end	Night	3 2 1 4 3 2 4 2 4 5% 70%	2200
October	1st to 10th	Night	2 2 1 4 2 3 3 2 4 5% 72%	3852
	11th to 20th	Night	2 2 1 2 2 2 2 2 3 5% 76%	3898
	21st to end	Night	2 2 1 2 2 2 3 2 3 4 77%	4252
November	1st to 10th	Night	3 3 1 3 3 2 3 2 5% 5% 70%	2460
	11th to 20th	Night	2 3 1 4 2 2 2 3 4 5% 72%	2537
	21st to end	Night	2 7% 2 4 4 3 3 3 4 5% 62%	2730
December	1st to 10th	Night	4 4 1 3 2 2 2 2 4 6% 70%	4370
	11th to 20th	Night	3 6% 2 4 3 3 4 3 4 6% 62%	4941
	21st to end	Night	3 7% 2 4 3 4 4 3 4 5% 62%	6611

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	25% 4 4 19% 33% 15%	4189
	11th to 20th	Day	21% 3 4 17% 24% 30%	4190
	21st to end	Day	29% 4 5% 10% 25% 27%	4609
February	1st to 10th	Day	28% 3 5% 15% 25% 23%	1800
	11th to 20th	Day	31% 4 5% 19% 22% 19%	1862
	21st to end	Day	29% 4 5% 14% 26% 21%	1788
March	1st to 10th	Day	24% 5% 5% 13% 32% 21%	4954
	11th to 20th	Day	32% 7% 5% 15% 28% 11%	5000
	21st to end	Day	30% 3 5% 22% 32% 8%	5486
April	1st to 10th	Day	19% 4 5% 18% 36% 16%	2245
	11th to 20th	Day	19% 4 3 14% 35% 24%	2374
	21st to end	Day	20% 4 5% 16% 39% 16%	2400
May	1st to 10th	Day	20% 4 4 16% 42% 15%	5870
	11th to 20th	Day	15% 5% 5% 10% 40% 25%	5844
	21st to end	Day	14% 2 2 7% 27% 47%	6424
June	1st to 10th	Day	15% 4 5% 14% 33% 29%	2600
	11th to 20th	Day	11% 3 4 8% 27% 48%	2600
	21st to end	Day	24% 6% 6% 11% 26% 27%	2600
July	1st to 10th	Day	25% 7% 6% 8% 18% 36%	5816
	11th to 20th	Day	33% 12% 14% 23% 12% 6%	5811
	21st to end	Day	35% 11% 17% 15% 15% 7%	6217
August	1st to 10th	Day	40% 12% 18% 15% 10% 5%	4208
	11th to 20th	Day	36% 10% 12% 19% 18% 5%	4143
	21st to end	Day	35% 10% 13% 18% 18% 5%	4311
September	1st to 10th	Day	36% 8% 9% 15% 19% 13%	2320
	11th to 20th	Day	25% 6% 7% 15% 32% 16%	2200
	21st to end	Day	22% 6% 6% 15% 31% 20%	2200
October	1st to 10th	Day	23% 5% 4 13% 23% 33%	3337
	11th to 20th	Day	18% 3 2 13% 44% 20%	3250
	21st to end	Day	10% 2 3 12% 39% 35%	3548
November	1st to 10th	Day	14% 3 4 23% 35% 21%	2059
	11th to 20th	Day	18% 4 5% 16% 33% 25%	2079
	21st to end	Day	26% 2 5% 15% 31% 20%	1890
December	1st to 10th	Day	19% 4 3 16% 38% 19%	3040
	11th to 20th	Day	26% 3 5% 13% 39% 14%	3498
	21st to end	Day	26% 3 6% 21% 29% 15%	4609
January	1st to 10th	Night	28% 4 5% 15% 35% 12%	5997
	11th to 20th	Night	16% 4 4 16% 33% 26%	6010
	21st to end	Night	34% 4 3 9% 26% 23%	6611
February	1st to 10th	Night	26% 3 6% 17% 23% 24%	2600
	11th to 20th	Night	30% 5% 5% 17% 24% 18%	2430
	21st to end	Night	27% 4 6% 13% 27% 23%	1840
March	1st to 10th	Night	24% 4 3 14% 37% 16%	4940
	11th to 20th	Night	27% 6% 7% 20% 27% 14%	5000
	21st to end	Night	22% 7% 5% 26% 31% 9%	5489
April	1st to 10th	Night	20% 4 4 23% 33% 15%	2155
	11th to 20th	Night	18% 2 3 17% 37% 22%	1977
	21st to end	Night	12% 3 5% 22% 41% 16%	2000
May	1st to 10th	Night	18% 4 5% 19% 42% 12%	4103
	11th to 20th	Night	11% 4 4 14% 44% 22%	4075
	21st to end	Night	10% 2 2 8% 32% 46%	4474
June	1st to 10th	Night	15% 4 5% 13% 31% 32%	1800
	11th to 20th	Night	8% 3 3 10% 29% 47%	1800
	21st to end	Night	20% 4 9% 12% 25% 30%	1800
July	1st to 10th	Night	22% 5% 8% 13% 18% 33%	4055
	11th to 20th	Night	38% 10% 19% 16% 11% 6%	4046
	21st to end	Night	32% 11% 23% 12% 17% 5%	4344
August	1st to 10th	Night	33% 13% 23% 14% 10% 6%	2928
	11th to 20th	Night	28% 10% 19% 22% 17% 4	2979
	21st to end	Night	30% 9% 16% 20% 20% 5%	3597
September	1st to 10th	Night	28% 8% 14% 19% 20% 11%	2075
	11th to 20th	Night	19% 5% 8% 18% 35% 15%	2200
	21st to end	Night	17% 4 6% 18% 33% 22%	2200
October	1st to 10th	Night	14% 4 5% 13% 31% 33%	3852
	11th to 20th	Night	12% 2 3 15% 42% 26%	3898
	21st to end	Night	12% 3 3 12% 36% 33%	4252
November	1st to 10th	Night	17% 3 4 20% 35% 21%	2460
	11th to 20th	Night	16% 4 5% 20% 29% 27%	2537
	21st to end	Night	24% 5% 5% 16% 29% 22%	2730
December	1st to 10th	Night	17% 2 5% 20% 33% 23%	4370
	11th to 20th	Night	25% 3 5% 12% 36% 19%	4941
	21st to end	Night	25% 3 5% 20% 26% 20%	6611

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	19% 26% 30% 17% 8% 1	330
	11th to 20th	Day	16% 22% 27% 22% 12% 2	330
	21st to end	Day	15% 24% 29% 18% 12% 2	363
February	1st to 10th	Day	18% 24% 28% 19% 9% 2	300
	11th to 20th	Day	25% 29% 26% 17% 4	398
	21st to end	Day	23% 32% 26% 15% 3	414
March	1st to 10th	Day	22% 33% 25% 15% 4 1	500
	11th to 20th	Day	21% 29% 27% 14% 8% 1	500
	21st to end	Day	22% 33% 29% 12% 5%	550
April	1st to 10th	Day	12% 32% 33% 16% 5% 2	500
	11th to 20th	Day	19% 29% 34% 13% 4 1	492
	21st to end	Day	16% 26% 36% 15% 6% 1	500
May	1st to 10th	Day	9% 27% 38% 20% 5% 1	503
	11th to 20th	Day	10% 22% 39% 19% 7% 3	528
	21st to end	Day	9% 25% 40% 18% 6% 2	573
June	1st to 10th	Day	4 17% 38% 30% 8% 2	530
	11th to 20th	Day	5% 16% 39% 24% 12% 3	530
	21st to end	Day	5% 12% 34% 31% 13% 4	530
July	1st to 10th	Day	5% 4 26% 37% 21% 7%	526
	11th to 20th	Day	9% 3 14% 34% 30% 10%	524
	21st to end	Day	7% 4 13% 34% 32% 10%	575
August	1st to 10th	Day	9% 2 14% 37% 29% 8%	527
	11th to 20th	Day	7% 6% 14% 37% 27% 9%	517
	21st to end	Day	7% 4 15% 37% 25% 12%	583
September	1st to 10th	Day	6% 7% 22% 35% 22% 7%	530
	11th to 20th	Day	6% 12% 33% 30% 15% 4	530
	21st to end	Day	8% 16% 29% 27% 16% 5%	530
October	1st to 10th	Day	9% 17% 29% 24% 16% 5%	371
	11th to 20th	Day	13% 17% 26% 28% 12% 4	330
	21st to end	Day	10% 19% 28% 25% 15% 3	363
November	1st to 10th	Day	9% 22% 29% 25% 13% 2	330
	11th to 20th	Day	11% 17% 28% 26% 16% 2	330
	21st to end	Day	18% 20% 31% 19% 11% 2	330
December	1st to 10th	Day	14% 22% 27% 27% 8% 2	330
	11th to 20th	Day	10% 28% 27% 23% 10% 2	330
	21st to end	Day	22% 22% 28% 21% 7% 1	363
January	1st to 10th	Night	11% 16% 27% 28% 13% 5%	840
	11th to 20th	Night	10% 15% 33% 26% 12% 3	840
	21st to end	Night	12% 19% 29% 25% 12% 3	924
February	1st to 10th	Night	9% 22% 27% 27% 13% 3	800
	11th to 20th	Night	11% 21% 34% 25% 8% 1	784
	21st to end	Night	13% 20% 35% 23% 8% 2	660
March	1st to 10th	Night	14% 21% 33% 23% 9% 1	800
	11th to 20th	Night	12% 14% 30% 26% 14% 3	800
	21st to end	Night	9% 18% 31% 28% 12% 2	880
April	1st to 10th	Night	7% 18% 34% 29% 12% 1	755
	11th to 20th	Night	9% 22% 29% 31% 7% 1	593
	21st to end	Night	5% 18% 30% 30% 15% 3	600
May	1st to 10th	Night	4 15% 28% 37% 15% 2	600
	11th to 20th	Night	5% 10% 30% 37% 17% 2	591
	21st to end	Night	5% 13% 28% 37% 17% 1	650
June	1st to 10th	Night	3 6% 23% 44% 21% 3	600
	11th to 20th	Night	4 5% 29% 40% 21% 1	600
	21st to end	Night	4 4 15% 38% 35% 5%	600
July	1st to 10th	Night	5% 2 8% 36% 44% 6%	585
	11th to 20th	Night	5% 1 6% 27% 48% 14%	582
	21st to end	Night	7% 1 5% 25% 49% 13%	657
August	1st to 10th	Night	5% 1 6% 21% 53% 14%	597
	11th to 20th	Night	6% 2 6% 24% 52% 11%	594
	21st to end	Night	4 1 6% 27% 48% 13%	660
September	1st to 10th	Night	6% 1 12% 34% 39% 8%	675
	11th to 20th	Night	5% 2 19% 36% 32% 6%	800
	21st to end	Night	4 9% 15% 37% 28% 8%	800
October	1st to 10th	Night	5% 12% 25% 36% 20% 2	800
	11th to 20th	Night	5% 10% 25% 38% 19% 3	800
	21st to end	Night	5% 12% 24% 29% 22% 7%	880
November	1st to 10th	Night	6% 12% 25% 35% 16% 6%	820
	11th to 20th	Night	5% 14% 29% 30% 17% 5%	840
	21st to end	Night	10% 17% 27% 28% 14% 5%	840
December	1st to 10th	Night	12% 15% 23% 30% 17% 2	840
	11th to 20th	Night	11% 16% 30% 29% 12% 2	840
	21st to end	Night	13% 18% 31% 26% 9% 3	924

Page generated at 2026-01-28 23:21:39. Version ac07

Copyright © 2026 Attilla Danko.