Gouldsboro
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Gouldsboro clear sky chart from 2005-11-06 to 2024-12-06.

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	15% 9% 4 8% 5% 5% 5% 4 6% 7% 33%	101673
	Night	14% 9% 4 8% 5% 4 4 4 5% 7% 35%	98045
Transparency	Day	47% 3 11% 24% 13% 2	105208
	Night	45% 3 12% 24% 14% 2	102599
Seeing	Day	24% 20% 29% 17% 8% 2	14943
	Night	22% 20% 29% 21% 8% 1	24209

By Month

Percentage Cloud Cover NE (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	12% 14% 5% 10% 6% 5% 4 4 4 5% 32%	2517
	11th to 20th	Day	12% 13% 7% 14% 9% 6% 4 3 4 4 24%	2524
	21st to end	Day	17% 13% 7% 12% 6% 5% 4 3 5% 5% 23%	3124
February	1st to 10th	Day	14% 12% 4 9% 7% 6% 5% 3 5% 6% 29%	1710
	11th to 20th	Day	13% 10% 3 8% 7% 6% 5% 5% 5% 6% 31%	1765
	21st to end	Day	16% 12% 4 10% 7% 4 4 4 4 6% 30%	1570
March	1st to 10th	Day	22% 12% 4 9% 5% 4 4 3 4 5% 28%	3134
	11th to 20th	Day	8% 8% 5% 9% 7% 5% 5% 4 6% 6% 35%	3480
	21st to end	Day	18% 10% 3 7% 5% 4 4 3 4 5% 37%	4031
April	1st to 10th	Day	15% 12% 3 9% 6% 5% 4 4 4 5% 33%	2280
	11th to 20th	Day	14% 11% 3 7% 6% 4 5% 3 5% 7% 36%	2254
	21st to end	Day	14% 8% 3 9% 5% 5% 5% 4 6% 6% 35%	2280
May	1st to 10th	Day	25% 9% 3 7% 5% 4 4 4 5% 6% 29%	4212
	11th to 20th	Day	23% 9% 3 9% 5% 5% 5% 4 5% 6% 25%	4398
	21st to end	Day	12% 7% 2 6% 5% 4 5% 4 7% 9% 39%	4837
June	1st to 10th	Day	15% 7% 3 7% 6% 5% 6% 4 6% 8% 33%	2660
	11th to 20th	Day	13% 9% 3 7% 5% 5% 6% 5% 6% 9% 32%	2660
	21st to end	Day	12% 7% 3 7% 5% 5% 5% 5% 7% 8% 36%	2660
July	1st to 10th	Day	8% 6% 3 9% 6% 6% 7% 5% 8% 9% 35%	4440
	11th to 20th	Day	10% 6% 3 7% 5% 5% 5% 5% 8% 11% 36%	4440
	21st to end	Day	13% 9% 3 8% 6% 5% 5% 5% 6% 7% 32%	4798
August	1st to 10th	Day	20% 8% 3 8% 5% 5% 6% 4 6% 7% 28%	4104
	11th to 20th	Day	13% 8% 3 7% 4 5% 5% 5% 7% 9% 35%	3800
	21st to end	Day	15% 6% 2 5% 4 4 4 4 6% 8% 42%	4180
September	1st to 10th	Day	17% 5% 3 6% 6% 4 5% 4 6% 6% 39%	2280
	11th to 20th	Day	13% 6% 2 5% 4 4 4 3 5% 7% 46%	2261
	21st to end	Day	17% 8% 3 8% 6% 5% 4 3 5% 6% 35%	2068
October	1st to 10th	Day	16% 9% 3 7% 5% 4 4 3 5% 6% 37%	1900
	11th to 20th	Day	13% 9% 3 8% 5% 4 4 4 5% 7% 39%	1900
	21st to end	Day	17% 9% 3 10% 4 4 4 3 5% 7% 33%	2007
November	1st to 10th	Day	12% 9% 3 7% 4 4 4 2 5% 7% 44%	1761
	11th to 20th	Day	14% 11% 3 8% 6% 4 4 4 5% 6% 36%	1800
	21st to end	Day	16% 10% 3 9% 6% 5% 6% 3 4 7% 31%	1600
December	1st to 10th	Day	14% 12% 5% 12% 5% 5% 5% 4 5% 6% 27%	1560
	11th to 20th	Day	18% 11% 5% 10% 5% 4 4 3 4 5% 29%	1906
	21st to end	Day	16% 13% 8% 12% 7% 6% 5% 4 5% 4 20%	2772
January	1st to 10th	Night	12% 8% 6% 10% 6% 5% 5% 4 6% 8% 30%	4429
	11th to 20th	Night	12% 12% 6% 13% 7% 5% 5% 4 5% 6% 26%	4431
	21st to end	Night	18% 13% 5% 9% 7% 6% 5% 4 5% 5% 24%	4532
February	1st to 10th	Night	14% 12% 3 8% 6% 4 4 4 5% 6% 34%	2470
	11th to 20th	Night	12% 10% 3 10% 6% 6% 5% 5% 7% 7% 29%	2299
	21st to end	Night	14% 11% 4 9% 6% 5% 5% 4 5% 5% 32%	1884
March	1st to 10th	Night	19% 12% 4 10% 4 4 4 3 5% 6% 30%	3702
	11th to 20th	Night	8% 8% 4 9% 6% 5% 5% 4 6% 7% 37%	3479
	21st to end	Night	12% 10% 4 9% 6% 5% 4 3 4 5% 39%	3600
April	1st to 10th	Night	13% 11% 5% 10% 6% 5% 5% 4 5% 6% 31%	1900
	11th to 20th	Night	15% 9% 4 7% 5% 4 4 4 5% 7% 37%	1875
	21st to end	Night	17% 9% 3 7% 5% 4 3 3 5% 6% 38%	1900
May	1st to 10th	Night	24% 10% 3 7% 4 4 4 3 5% 6% 29%	2758
	11th to 20th	Night	21% 13% 3 7% 4 4 4 4 5% 7% 28%	2495
	21st to end	Night	11% 8% 3 8% 5% 4 5% 4 7% 8% 37%	2738
June	1st to 10th	Night	14% 7% 2 6% 4 4 4 4 6% 9% 40%	1520
	11th to 20th	Night	11% 6% 3 7% 5% 5% 5% 4 6% 8% 40%	1520
	21st to end	Night	10% 5% 2 5% 5% 4 5% 5% 7% 9% 43%	1520
July	1st to 10th	Night	8% 6% 2 9% 5% 5% 5% 4 7% 9% 39%	2520
	11th to 20th	Night	10% 6% 3 7% 4 5% 5% 5% 8% 10% 38%	2520
	21st to end	Night	15% 7% 2 6% 5% 5% 5% 4 5% 7% 40%	2739
August	1st to 10th	Night	20% 9% 2 7% 4 4 3 3 7% 7% 33%	2825
	11th to 20th	Night	15% 7% 3 6% 4 3 4 4 5% 6% 43%	2996
	21st to end	Night	11% 7% 2 5% 3 3 4 4 6% 7% 48%	3476
September	1st to 10th	Night	14% 7% 2 7% 3 4 4 3 6% 7% 44%	1900
	11th to 20th	Night	11% 6% 3 7% 4 3 2 3 5% 6% 50%	1919
	21st to end	Night	17% 7% 3 7% 4 3 4 4 5% 6% 40%	2108
October	1st to 10th	Night	18% 8% 2 7% 4 4 4 3 4 6% 41%	2280
	11th to 20th	Night	14% 8% 2 7% 4 3 4 3 5% 6% 43%	2280
	21st to end	Night	18% 10% 3 6% 3 3 4 4 5% 6% 37%	2589
November	1st to 10th	Night	10% 9% 3 7% 5% 3 4 3 5% 5% 46%	2537
	11th to 20th	Night	15% 9% 3 7% 5% 4 4 4 5% 7% 37%	2600
	21st to end	Night	13% 8% 3 9% 6% 5% 5% 4 5% 7% 35%	2795
December	1st to 10th	Night	16% 10% 4 10% 6% 6% 6% 4 6% 6% 28%	2737
	11th to 20th	Night	16% 10% 4 10% 5% 5% 4 4 6% 6% 29%	3288
	21st to end	Night	18% 12% 5% 10% 6% 5% 5% 3 5% 6% 24%	4884

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	49% 2 9% 31% 9% 2	2518
	11th to 20th	Day	59% 2 9% 20% 8% 2	2524
	21st to end	Day	57% 2 10% 20% 9% 1	3124
February	1st to 10th	Day	54% 3 11% 19% 12% 1	1710
	11th to 20th	Day	48% 4 9% 24% 14% 1	1774
	21st to end	Day	54% 1 9% 22% 10% 3	1570
March	1st to 10th	Day	55% 2 10% 21% 9% 2	3137
	11th to 20th	Day	42% 2 13% 29% 12% 2	3480
	21st to end	Day	48% 2 9% 15% 22% 4	4031
April	1st to 10th	Day	51% 3 9% 21% 13% 3	2280
	11th to 20th	Day	48% 3 10% 24% 13% 2	2254
	21st to end	Day	46% 4 9% 23% 14% 5%	2280
May	1st to 10th	Day	55% 2 11% 20% 10% 1	4226
	11th to 20th	Day	58% 3 12% 18% 8% 1	4402
	21st to end	Day	38% 4 13% 28% 16% 2	4837
June	1st to 10th	Day	46% 4 13% 23% 13% 1	2660
	11th to 20th	Day	46% 4 14% 23% 11% 2	2660
	21st to end	Day	43% 5% 13% 27% 11%	2660
July	1st to 10th	Day	43% 7% 13% 25% 12%	4370
	11th to 20th	Day	40% 5% 17% 25% 13%	4365
	21st to end	Day	50% 3 11% 19% 15% 1	4645
August	1st to 10th	Day	52% 4 13% 21% 9%	4091
	11th to 20th	Day	43% 4 13% 30% 9%	3838
	21st to end	Day	38% 3 10% 34% 13% 1	4180
September	1st to 10th	Day	43% 4 11% 23% 17% 2	2280
	11th to 20th	Day	36% 4 10% 25% 24% 2	2261
	21st to end	Day	48% 4 9% 19% 18% 2	2068
October	1st to 10th	Day	44% 3 8% 23% 20% 2	3160
	11th to 20th	Day	36% 3 8% 29% 17% 7%	3140
	21st to end	Day	32% 2 16% 27% 19% 4	3284
November	1st to 10th	Day	38% 2 12% 26% 19% 3	1761
	11th to 20th	Day	45% 2 10% 24% 16% 3	1800
	21st to end	Day	48% 3 13% 25% 10% 1	1600
December	1st to 10th	Day	53% 3 15% 17% 11% 1	1560
	11th to 20th	Day	51% 2 15% 22% 9% 1	1906
	21st to end	Day	61% 2 11% 18% 7%	2772
January	1st to 10th	Night	46% 2 11% 29% 10% 2	4429
	11th to 20th	Night	54% 3 11% 22% 9% 1	4431
	21st to end	Night	56% 2 9% 22% 11% 1	4532
February	1st to 10th	Night	47% 3 14% 23% 11% 2	2470
	11th to 20th	Night	46% 4 10% 22% 16% 2	2301
	21st to end	Night	49% 2 8% 24% 14% 3	1884
March	1st to 10th	Night	53% 2 10% 22% 10% 2	3712
	11th to 20th	Night	39% 2 15% 28% 14% 2	3480
	21st to end	Night	45% 3 8% 18% 21% 6%	3600
April	1st to 10th	Night	50% 3 9% 22% 13% 2	1900
	11th to 20th	Night	46% 4 11% 22% 17% 1	1875
	21st to end	Night	45% 3 10% 22% 17% 3	1900
May	1st to 10th	Night	55% 3 10% 22% 8% 1	2764
	11th to 20th	Night	57% 3 13% 16% 10% 1	2496
	21st to end	Night	41% 4 16% 24% 14% 2	2739
June	1st to 10th	Night	40% 5% 11% 27% 17%	1520
	11th to 20th	Night	39% 4 18% 28% 11% 1	1520
	21st to end	Night	35% 5% 16% 31% 13%	1520
July	1st to 10th	Night	41% 6% 17% 20% 15% 1	2480
	11th to 20th	Night	39% 6% 16% 28% 11% 1	2472
	21st to end	Night	44% 4 14% 19% 18% 1	2651
August	1st to 10th	Night	46% 6% 18% 22% 8%	2814
	11th to 20th	Night	42% 3 16% 27% 11%	3024
	21st to end	Night	33% 4 12% 34% 16% 1	3476
September	1st to 10th	Night	39% 4 12% 27% 17% 1	1900
	11th to 20th	Night	34% 3 10% 26% 24% 2	1919
	21st to end	Night	45% 3 8% 24% 19% 2	2108
October	1st to 10th	Night	43% 3 10% 26% 17% 1	3800
	11th to 20th	Night	32% 2 10% 28% 21% 7%	3779
	21st to end	Night	32% 2 16% 28% 18% 3	4262
November	1st to 10th	Night	37% 3 12% 24% 20% 3	2537
	11th to 20th	Night	44% 2 10% 24% 18% 3	2600
	21st to end	Night	42% 3 16% 27% 12% 1	2795
December	1st to 10th	Night	51% 4 12% 24% 9% 1	2737
	11th to 20th	Night	48% 3 13% 21% 14% 1	3288
	21st to end	Night	55% 2 12% 22% 8%	4884

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	39% 24% 26% 9% 1 1	180
	11th to 20th	Day	40% 29% 25% 5% 1	182
	21st to end	Day	27% 32% 30% 7% 3	297
February	1st to 10th	Day	33% 34% 26% 6% 1	270
	11th to 20th	Day	37% 29% 30% 4	373
	21st to end	Day	34% 30% 27% 7% 2	382
March	1st to 10th	Day	36% 22% 28% 12% 1	460
	11th to 20th	Day	31% 29% 26% 10% 3 1	460
	21st to end	Day	34% 28% 24% 9% 4 1	506
April	1st to 10th	Day	33% 26% 24% 12% 5%	460
	11th to 20th	Day	28% 26% 27% 13% 5% 1	452
	21st to end	Day	27% 25% 32% 10% 4 3	460
May	1st to 10th	Day	33% 23% 26% 11% 6% 2	463
	11th to 20th	Day	25% 18% 33% 15% 7% 1	487
	21st to end	Day	19% 13% 29% 25% 11% 2	529
June	1st to 10th	Day	21% 15% 30% 21% 10% 2	490
	11th to 20th	Day	18% 21% 24% 24% 13%	490
	21st to end	Day	17% 17% 33% 24% 9% 1	490
July	1st to 10th	Day	12% 12% 31% 26% 16% 4	485
	11th to 20th	Day	9% 10% 32% 32% 15% 2	484
	21st to end	Day	15% 12% 36% 25% 9% 3	532
August	1st to 10th	Day	15% 9% 30% 25% 16% 5%	486
	11th to 20th	Day	13% 10% 28% 29% 15% 4	479
	21st to end	Day	15% 11% 29% 27% 11% 7%	539
September	1st to 10th	Day	21% 12% 23% 23% 14% 6%	490
	11th to 20th	Day	13% 10% 30% 22% 15% 10%	490
	21st to end	Day	26% 16% 27% 19% 10% 3	490
October	1st to 10th	Day	24% 15% 26% 21% 10% 4	490
	11th to 20th	Day	22% 22% 30% 19% 6% 2	490
	21st to end	Day	24% 24% 30% 16% 5% 1	494
November	1st to 10th	Day	23% 25% 26% 18% 7% 2	395
	11th to 20th	Day	28% 27% 29% 13% 3 1	400
	21st to end	Day	37% 25% 29% 8% 2	200
December	1st to 10th	Day	32% 31% 27% 7% 3 1	190
	11th to 20th	Day	38% 27% 28% 5% 2	180
	21st to end	Day	32% 29% 27% 10% 2	198
January	1st to 10th	Night	25% 29% 32% 11% 2	760
	11th to 20th	Night	28% 26% 30% 15% 1	760
	21st to end	Night	19% 32% 34% 14% 1	836
February	1st to 10th	Night	29% 25% 32% 12% 1	760
	11th to 20th	Night	27% 33% 32% 8%	743
	21st to end	Night	32% 28% 27% 11% 2	628
March	1st to 10th	Night	31% 24% 30% 13% 3	760
	11th to 20th	Night	26% 29% 28% 14% 3	760
	21st to end	Night	25% 26% 30% 13% 5% 1	836
April	1st to 10th	Night	24% 26% 31% 17% 3	760
	11th to 20th	Night	24% 22% 31% 17% 6%	751
	21st to end	Night	25% 19% 31% 21% 5%	760
May	1st to 10th	Night	28% 15% 29% 21% 7% 1	533
	11th to 20th	Night	18% 16% 36% 25% 5% 1	374
	21st to end	Night	15% 12% 27% 34% 12%	411
June	1st to 10th	Night	16% 10% 28% 35% 11% 1	380
	11th to 20th	Night	14% 9% 31% 36% 10% 1	380
	21st to end	Night	12% 8% 29% 41% 9%	380
July	1st to 10th	Night	12% 5% 28% 37% 17% 1	370
	11th to 20th	Night	10% 7% 26% 38% 17% 1	368
	21st to end	Night	14% 8% 26% 38% 13% 1	416
August	1st to 10th	Night	14% 3 25% 39% 17% 2	567
	11th to 20th	Night	14% 7% 19% 37% 21% 2	685
	21st to end	Night	14% 8% 23% 31% 21% 1	836
September	1st to 10th	Night	17% 9% 29% 27% 17% 2	760
	11th to 20th	Night	13% 9% 27% 25% 20% 6%	760
	21st to end	Night	21% 12% 23% 27% 14% 2	760
October	1st to 10th	Night	23% 15% 22% 23% 15% 1	760
	11th to 20th	Night	19% 18% 30% 26% 7%	760
	21st to end	Night	26% 21% 30% 17% 5%	836
November	1st to 10th	Night	18% 24% 30% 21% 7% 1	780
	11th to 20th	Night	26% 26% 27% 16% 5% 1	800
	21st to end	Night	23% 25% 32% 15% 5%	800
December	1st to 10th	Night	27% 26% 30% 13% 4	783
	11th to 20th	Night	26% 26% 30% 16% 1	760
	21st to end	Night	26% 29% 30% 13% 2	836

Page generated at 2024-12-03 06:45:15. Version ac07

Copyright © 2024 Attilla Danko.