Pocatello
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Pocatello clear sky chart from 2005-11-06 to 2024-11-25.

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	7% 9% 3 6% 4 4 4 3 5% 6% 50%	105282
	Night	7% 10% 3 7% 4 4 4 3 5% 6% 46%	102859
Transparency	Day	34% 5% 10% 20% 19% 12%	105035
	Night	37% 5% 11% 19% 17% 10%	102694
Seeing	Day	13% 13% 27% 28% 16% 4	15217
	Night	14% 7% 23% 36% 17% 2	24896

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	9% 23% 7% 13% 6% 5% 4 2 3 4 24%	2539
	11th to 20th	Day	10% 21% 7% 11% 5% 3 4 3 4 5% 27%	2618
	21st to end	Day	12% 20% 5% 12% 4 4 3 3 5% 5% 26%	3146
February	1st to 10th	Day	11% 17% 6% 11% 6% 4 4 4 5% 6% 26%	1710
	11th to 20th	Day	11% 19% 5% 10% 5% 3 4 3 6% 5% 30%	1717
	21st to end	Day	9% 18% 6% 11% 5% 5% 5% 3 5% 6% 28%	1570
March	1st to 10th	Day	7% 18% 6% 12% 5% 5% 4 3 4 6% 30%	3282
	11th to 20th	Day	7% 11% 5% 6% 4 4 3 3 5% 4 49%	3490
	21st to end	Day	10% 20% 6% 12% 6% 5% 5% 4 6% 6% 20%	3825
April	1st to 10th	Day	12% 12% 4 9% 5% 4 5% 5% 5% 6% 34%	2148
	11th to 20th	Day	9% 12% 4 7% 5% 5% 4 4 5% 7% 40%	2437
	21st to end	Day	9% 11% 3 8% 5% 4 4 4 6% 8% 39%	2470
May	1st to 10th	Day	9% 14% 3 6% 4 4 5% 4 5% 7% 39%	4110
	11th to 20th	Day	5% 4 2 4 4 4 4 4 5% 7% 57%	4071
	21st to end	Day	9% 7% 2 6% 4 4 5% 3 6% 6% 46%	4605
June	1st to 10th	Day	7% 6% 2 4 4 4 4 5% 6% 9% 49%	2772
	11th to 20th	Day	7% 5% 2 5% 4 4 5% 4 5% 7% 54%	2850
	21st to end	Day	3 2 1 3 2 2 3 3 4 6% 70%	2850
July	1st to 10th	Day	1 1 1 1 2 2 2 2 4 5% 79%	4496
	11th to 20th	Day	1 2 1 3 3 3 3 3 5% 7% 68%	4389
	21st to end	Day	3 3 1 3 4 3 4 3 6% 6% 65%	4454
August	1st to 10th	Day	2 3 2 4 3 4 4 3 6% 8% 60%	4092
	11th to 20th	Day	2 2 1 3 3 3 3 3 4 7% 70%	4028
	21st to end	Day	2 2 1 2 2 2 2 2 5% 6% 74%	4521
September	1st to 10th	Day	4 2 1 4 2 3 3 2 4 5% 69%	2175
	11th to 20th	Day	4 3 1 4 3 3 3 3 5% 7% 63%	2090
	21st to end	Day	7% 3 1 4 3 3 3 3 3 6% 64%	2090
October	1st to 10th	Day	6% 4 1 3 2 3 3 3 4 4 66%	3344
	11th to 20th	Day	5% 6% 2 5% 3 3 3 3 4 6% 60%	3150
	21st to end	Day	7% 10% 2 6% 4 4 4 4 6% 7% 45%	3265
November	1st to 10th	Day	12% 12% 3 6% 5% 4 4 3 4 6% 40%	1764
	11th to 20th	Day	11% 12% 4 6% 4 3 4 3 7% 7% 39%	1752
	21st to end	Day	9% 12% 3 8% 5% 4 4 4 5% 5% 40%	1552
December	1st to 10th	Day	13% 15% 5% 11% 5% 4 3 3 4 6% 31%	1520
	11th to 20th	Day	12% 14% 5% 12% 7% 5% 5% 5% 6% 6% 24%	1880
	21st to end	Day	8% 14% 5% 9% 4 5% 4 4 6% 8% 33%	2510
January	1st to 10th	Night	10% 19% 8% 13% 4 4 4 3 4 6% 25%	4406
	11th to 20th	Night	12% 22% 8% 12% 5% 3 4 3 4 5% 23%	4328
	21st to end	Night	10% 21% 5% 9% 5% 4 4 3 4 6% 28%	4521
February	1st to 10th	Night	12% 15% 5% 11% 5% 4 5% 3 6% 6% 28%	2470
	11th to 20th	Night	10% 15% 5% 9% 5% 3 4 3 5% 6% 37%	2345
	21st to end	Night	7% 15% 5% 11% 7% 5% 3 4 5% 6% 31%	1884
March	1st to 10th	Night	7% 13% 4 10% 6% 5% 6% 4 6% 6% 32%	3591
	11th to 20th	Night	4 9% 3 5% 4 4 6% 4 5% 7% 49%	3490
	21st to end	Night	8% 14% 4 9% 5% 5% 5% 5% 6% 8% 31%	3828
April	1st to 10th	Night	9% 12% 3 7% 5% 4 4 3 5% 6% 42%	2026
	11th to 20th	Night	8% 11% 4 9% 5% 4 4 3 6% 5% 42%	1691
	21st to end	Night	8% 8% 3 6% 4 4 5% 5% 5% 5% 48%	1710
May	1st to 10th	Night	8% 13% 3 7% 5% 4 4 3 4 6% 42%	2860
	11th to 20th	Night	5% 5% 2 5% 4 3 4 4 5% 7% 54%	2834
	21st to end	Night	9% 6% 2 5% 5% 4 5% 3 5% 6% 50%	2964
June	1st to 10th	Night	7% 5% 1 5% 4 3 5% 4 7% 9% 48%	1403
	11th to 20th	Night	8% 4 2 5% 3 3 4 3 5% 6% 57%	1330
	21st to end	Night	2 2 2 4 3 2 3 2 5% 6% 68%	1330
July	1st to 10th	Night	2 2 1 3 2 2 3 2 4 6% 73%	2459
	11th to 20th	Night	1 2 1 2 2 3 4 4 6% 7% 69%	2569
	21st to end	Night	1 2 1 3 3 4 3 4 5% 7% 67%	3109
August	1st to 10th	Night	2 1 1 4 3 3 4 4 7% 8% 63%	2847
	11th to 20th	Night	2 3 1 4 4 4 4 3 5% 6% 64%	2811
	21st to end	Night	2 2 1 3 2 2 2 2 4 5% 75%	3146
September	1st to 10th	Night	3 3 1 3 2 3 3 3 4 6% 70%	2000
	11th to 20th	Night	5% 4 1 4 3 3 4 3 5% 6% 61%	2090
	21st to end	Night	8% 3 2 4 2 3 3 2 4 4 66%	2090
October	1st to 10th	Night	5% 3 1 3 2 2 2 2 4 5% 71%	3630
	11th to 20th	Night	9% 6% 2 6% 4 3 3 3 4 5% 55%	3778
	21st to end	Night	6% 9% 2 5% 4 4 5% 3 6% 8% 48%	4292
November	1st to 10th	Night	11% 11% 3 6% 4 4 4 4 5% 7% 43%	2535
	11th to 20th	Night	10% 11% 4 6% 5% 4 4 4 5% 7% 40%	2625
	21st to end	Night	7% 12% 5% 8% 5% 4 4 3 5% 6% 39%	2723
December	1st to 10th	Night	12% 15% 4 9% 5% 3 4 3 6% 6% 33%	2660
	11th to 20th	Night	11% 15% 5% 11% 6% 5% 4 3 5% 6% 28%	3311
	21st to end	Night	11% 13% 5% 11% 6% 5% 4 3 4 6% 32%	5173

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% 7% 12% 16% 3 1	2539
	11th to 20th	Day	60% 7% 13% 15% 4 1	2618
	21st to end	Day	59% 10% 12% 12% 5% 1	3146
February	1st to 10th	Day	57% 8% 12% 17% 4 1	1710
	11th to 20th	Day	54% 7% 16% 17% 5% 1	1726
	21st to end	Day	54% 6% 16% 16% 7% 1	1570
March	1st to 10th	Day	52% 6% 12% 22% 6% 1	3282
	11th to 20th	Day	37% 5% 12% 32% 14% 1	3490
	21st to end	Day	59% 8% 16% 13% 4	3825
April	1st to 10th	Day	47% 7% 15% 17% 12% 3	2148
	11th to 20th	Day	42% 5% 11% 23% 17% 2	2440
	21st to end	Day	41% 5% 13% 25% 16% 1	2470
May	1st to 10th	Day	42% 4 11% 24% 16% 3	4110
	11th to 20th	Day	24% 5% 10% 30% 25% 6%	4074
	21st to end	Day	34% 6% 12% 27% 19% 2	4605
June	1st to 10th	Day	30% 7% 14% 29% 18% 2	2772
	11th to 20th	Day	28% 5% 11% 22% 23% 11%	2850
	21st to end	Day	14% 3 7% 21% 36% 19%	2850
July	1st to 10th	Day	9% 2 4 10% 25% 51%	4427
	11th to 20th	Day	15% 3 4 9% 24% 46%	4314
	21st to end	Day	18% 3 4 11% 28% 35%	4314
August	1st to 10th	Day	21% 4 4 13% 29% 28%	4078
	11th to 20th	Day	15% 3 4 16% 39% 23%	4067
	21st to end	Day	12% 3 4 20% 31% 30%	4520
September	1st to 10th	Day	17% 3 8% 15% 32% 25%	2175
	11th to 20th	Day	20% 4 10% 24% 27% 15%	2090
	21st to end	Day	22% 4 8% 24% 32% 10%	2090
October	1st to 10th	Day	22% 4 6% 18% 34% 17%	3344
	11th to 20th	Day	27% 3 8% 35% 21% 6%	3150
	21st to end	Day	35% 4 15% 28% 16% 1	3265
November	1st to 10th	Day	45% 6% 14% 22% 12% 1	1764
	11th to 20th	Day	41% 7% 19% 23% 8% 2	1752
	21st to end	Day	45% 5% 17% 21% 10% 2	1552
December	1st to 10th	Day	54% 9% 14% 16% 4 3	1520
	11th to 20th	Day	58% 9% 13% 17% 2	1878
	21st to end	Day	49% 7% 17% 19% 8%	2510
January	1st to 10th	Night	58% 7% 11% 18% 4	4406
	11th to 20th	Night	62% 6% 13% 14% 4 1	4328
	21st to end	Night	56% 11% 14% 12% 6% 1	4521
February	1st to 10th	Night	54% 8% 15% 17% 5%	2470
	11th to 20th	Night	49% 7% 15% 19% 9% 1	2346
	21st to end	Night	52% 6% 13% 20% 7% 2	1884
March	1st to 10th	Night	47% 7% 15% 20% 11% 1	3591
	11th to 20th	Night	31% 7% 17% 28% 17% 1	3490
	21st to end	Night	46% 9% 16% 24% 5% 1	3828
April	1st to 10th	Night	42% 5% 14% 21% 15% 4	2026
	11th to 20th	Night	42% 6% 13% 21% 16% 2	1691
	21st to end	Night	36% 5% 12% 24% 22% 1	1710
May	1st to 10th	Night	40% 5% 11% 21% 19% 4	2860
	11th to 20th	Night	25% 6% 10% 24% 29% 7%	2835
	21st to end	Night	31% 6% 12% 23% 25% 3	2964
June	1st to 10th	Night	30% 7% 14% 23% 23% 4	1403
	11th to 20th	Night	27% 5% 10% 19% 26% 13%	1330
	21st to end	Night	16% 3 5% 15% 33% 28%	1330
July	1st to 10th	Night	14% 3 3 8% 20% 53%	2419
	11th to 20th	Night	14% 3 3 7% 21% 53%	2521
	21st to end	Night	16% 2 3 11% 31% 37%	3011
August	1st to 10th	Night	16% 4 4 11% 24% 40%	2838
	11th to 20th	Night	21% 2 4 13% 35% 25%	2838
	21st to end	Night	14% 3 4 15% 32% 33%	3146
September	1st to 10th	Night	17% 3 7% 12% 28% 33%	2000
	11th to 20th	Night	24% 4 6% 20% 27% 19%	2090
	21st to end	Night	22% 3 6% 23% 33% 13%	2090
October	1st to 10th	Night	17% 3 7% 17% 37% 20%	3630
	11th to 20th	Night	32% 3 7% 30% 21% 8%	3778
	21st to end	Night	33% 5% 11% 30% 18% 2	4292
November	1st to 10th	Night	41% 5% 13% 22% 17% 2	2535
	11th to 20th	Night	42% 7% 16% 24% 11% 1	2625
	21st to end	Night	44% 5% 16% 23% 9% 2	2723
December	1st to 10th	Night	51% 8% 16% 16% 7% 2	2660
	11th to 20th	Night	56% 7% 15% 18% 4	3312
	21st to end	Night	52% 6% 16% 16% 9%	5173

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	26% 17% 17% 23% 16% 1	180
	11th to 20th	Day	18% 12% 33% 22% 13% 3	204
	21st to end	Day	20% 13% 29% 26% 11% 1	297
February	1st to 10th	Day	24% 19% 30% 21% 6%	270
	11th to 20th	Day	19% 21% 28% 22% 8% 2	322
	21st to end	Day	19% 21% 33% 20% 7% 1	382
March	1st to 10th	Day	22% 19% 32% 21% 5%	460
	11th to 20th	Day	12% 19% 30% 26% 12% 1	460
	21st to end	Day	20% 22% 32% 21% 5%	506
April	1st to 10th	Day	23% 20% 24% 23% 8% 1	460
	11th to 20th	Day	20% 24% 31% 16% 10%	452
	21st to end	Day	16% 20% 29% 24% 9% 2	460
May	1st to 10th	Day	11% 20% 32% 23% 12% 2	463
	11th to 20th	Day	14% 15% 27% 25% 15% 3	488
	21st to end	Day	15% 9% 24% 27% 18% 7%	605
June	1st to 10th	Day	8% 10% 25% 28% 23% 5%	680
	11th to 20th	Day	13% 13% 28% 30% 14% 3	680
	21st to end	Day	4 6% 26% 33% 24% 6%	680
July	1st to 10th	Day	2 7% 23% 38% 25% 6%	536
	11th to 20th	Day	2 6% 32% 39% 17% 3	484
	21st to end	Day	3 4 21% 38% 27% 6%	531
August	1st to 10th	Day	7% 5% 27% 34% 22% 5%	487
	11th to 20th	Day	3 6% 28% 34% 22% 6%	477
	21st to end	Day	4 8% 22% 33% 26% 6%	539
September	1st to 10th	Day	4 7% 24% 30% 26% 9%	490
	11th to 20th	Day	7% 11% 27% 27% 22% 7%	490
	21st to end	Day	9% 10% 21% 33% 20% 7%	490
October	1st to 10th	Day	12% 11% 24% 24% 21% 8%	409
	11th to 20th	Day	12% 16% 17% 22% 25% 8%	300
	21st to end	Day	15% 16% 24% 32% 11% 2	330
November	1st to 10th	Day	18% 16% 26% 24% 11% 4	300
	11th to 20th	Day	18% 12% 33% 24% 11% 2	300
	21st to end	Day	16% 12% 28% 29% 13% 1	282
December	1st to 10th	Day	23% 8% 26% 31% 9% 3	270
	11th to 20th	Day	25% 9% 31% 25% 9%	255
	21st to end	Day	26% 12% 30% 19% 12% 2	198
January	1st to 10th	Night	20% 8% 24% 32% 14% 1	760
	11th to 20th	Night	22% 10% 23% 29% 14% 3	760
	21st to end	Night	22% 7% 21% 33% 15% 2	836
February	1st to 10th	Night	22% 11% 27% 30% 10% 1	760
	11th to 20th	Night	18% 8% 29% 34% 9% 2	744
	21st to end	Night	14% 13% 29% 31% 11% 2	628
March	1st to 10th	Night	14% 11% 31% 34% 10% 1	760
	11th to 20th	Night	10% 8% 29% 37% 15% 1	760
	21st to end	Night	19% 9% 26% 36% 9% 1	836
April	1st to 10th	Night	16% 12% 25% 32% 13% 1	743
	11th to 20th	Night	15% 10% 32% 33% 9% 1	563
	21st to end	Night	12% 9% 25% 35% 16% 2	570
May	1st to 10th	Night	11% 11% 21% 38% 17% 2	570
	11th to 20th	Night	9% 7% 21% 36% 23% 3	561
	21st to end	Night	14% 8% 17% 36% 21% 4	617
June	1st to 10th	Night	9% 6% 17% 39% 26% 3	453
	11th to 20th	Night	10% 6% 26% 39% 17% 1	380
	21st to end	Night	3 2 17% 44% 28% 5%	380
July	1st to 10th	Night	3 1 12% 49% 32% 4	370
	11th to 20th	Night	2 2 20% 49% 27% 1	384
	21st to end	Night	3 1 12% 46% 34% 4	624
August	1st to 10th	Night	3 2 16% 49% 28% 2	567
	11th to 20th	Night	4 2 14% 44% 32% 3	564
	21st to end	Night	4 3 17% 45% 27% 4	627
September	1st to 10th	Night	5% 3 18% 43% 27% 5%	708
	11th to 20th	Night	7% 3 19% 40% 24% 6%	760
	21st to end	Night	10% 4 17% 37% 24% 7%	760
October	1st to 10th	Night	12% 4 21% 39% 23% 3	760
	11th to 20th	Night	12% 7% 18% 37% 23% 3	760
	21st to end	Night	10% 9% 24% 39% 15% 3	836
November	1st to 10th	Night	17% 9% 22% 35% 14% 3	780
	11th to 20th	Night	16% 9% 27% 34% 12% 1	825
	21st to end	Night	15% 9% 24% 35% 14% 3	973
December	1st to 10th	Night	19% 10% 26% 35% 9% 1	950
	11th to 20th	Night	23% 9% 27% 29% 11% 1	950
	21st to end	Night	27% 11% 28% 26% 8% 1	1017

Page generated at 2024-11-22 06:02:28. Version ac07

Copyright © 2024 Attilla Danko.