Lodi
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Lodi clear sky chart from 2005-11-06 to 2024-11-30.

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% 4 1 4 2 2 3 2 4 5% 66%	105299
	Night	8% 4 1 4 3 3 3 2 4 5% 63%	103025
Transparency	Day	22% 3 7% 18% 25% 25%	105052
	Night	24% 4 8% 19% 23% 22%	102861
Seeing	Day	7% 5% 17% 29% 29% 14%	15350
	Night	9% 3 15% 40% 29% 4	24711

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	21% 11% 4 8% 4 4 3 3 4 6% 32%	2540
	11th to 20th	Day	19% 11% 5% 9% 5% 5% 4 3 3 5% 31%	2860
	21st to end	Day	21% 11% 4 9% 5% 4 4 3 5% 7% 28%	3146
February	1st to 10th	Day	17% 5% 3 6% 5% 5% 4 3 4 5% 44%	1710
	11th to 20th	Day	14% 6% 2 5% 3 5% 5% 3 5% 7% 46%	1793
	21st to end	Day	14% 5% 2 5% 3 3 3 3 4 7% 49%	1570
March	1st to 10th	Day	13% 8% 3 8% 6% 6% 6% 5% 7% 7% 32%	3262
	11th to 20th	Day	11% 4 2 3 3 3 2 3 4 6% 59%	3490
	21st to end	Day	11% 7% 3 6% 4 5% 5% 5% 6% 8% 39%	3964
April	1st to 10th	Day	12% 5% 2 5% 3 3 3 3 5% 7% 50%	2280
	11th to 20th	Day	9% 4 2 4 3 3 3 3 5% 6% 59%	2249
	21st to end	Day	6% 3 1 3 2 2 3 3 4 8% 65%	2280
May	1st to 10th	Day	5% 2 1 2 2 2 2 1 3 4 77%	3829
	11th to 20th	Day	2 1 1 2 1 1 1 2 2 3 83%	4332
	21st to end	Day	2 1 2 1 1 2 2 3 5% 80%	4813
June	1st to 10th	Day	3 3 1 2 2 3 2 3 3 6% 72%	2660
	11th to 20th	Day	1 1 1 2 2 2 3 4 84%	2660
	21st to end	Day	2 1 1 1 1 1 1 2 3 85%	2660
July	1st to 10th	Day	1 1 1 1 1 2 94%	4420
	11th to 20th	Day	1 1 1 2 1 1 1 1 2 3 85%	4339
	21st to end	Day	1 1 1 1 1 1 2 3 90%	4455
August	1st to 10th	Day	1 2 1 1 1 1 2 2 3 5% 81%	4091
	11th to 20th	Day	1 1 1 1 1 2 3 90%	3762
	21st to end	Day	1 1 1 1 1 1 1 1 3 89%	4180
September	1st to 10th	Day	1 1 1 1 1 1 1 2 3 89%	2280
	11th to 20th	Day	2 2 1 2 2 1 2 2 3 5% 78%	2280
	21st to end	Day	3 2 1 2 1 1 2 1 3 4 81%	2048
October	1st to 10th	Day	1 1 1 2 2 2 2 2 4 5% 78%	3180
	11th to 20th	Day	3 2 1 3 2 2 2 2 3 5% 74%	3161
	21st to end	Day	4 3 1 3 3 3 3 3 5% 7% 65%	3448
November	1st to 10th	Day	7% 4 2 5% 3 3 4 4 5% 7% 57%	1835
	11th to 20th	Day	10% 6% 2 5% 5% 3 4 3 5% 7% 51%	1800
	21st to end	Day	12% 7% 2 3 4 3 4 2 5% 8% 50%	1680
December	1st to 10th	Day	13% 8% 3 8% 5% 3 4 3 4 7% 44%	1520
	11th to 20th	Day	25% 10% 4 8% 5% 4 5% 2 4 6% 27%	1928
	21st to end	Day	13% 9% 4 10% 6% 6% 5% 4 7% 9% 28%	2794
January	1st to 10th	Night	14% 6% 3 7% 5% 4 4 3 5% 7% 42%	4402
	11th to 20th	Night	20% 8% 3 8% 4 5% 4 3 5% 7% 32%	4110
	21st to end	Night	20% 8% 3 7% 5% 4 4 3 5% 7% 33%	4521
February	1st to 10th	Night	17% 6% 2 4 3 3 3 3 4 6% 50%	2470
	11th to 20th	Night	12% 4 2 4 4 3 3 3 6% 9% 50%	2274
	21st to end	Night	13% 4 2 4 3 3 4 3 4 5% 54%	1884
March	1st to 10th	Night	15% 8% 3 8% 5% 3 4 4 5% 6% 39%	3595
	11th to 20th	Night	12% 5% 1 4 2 3 2 2 3 5% 61%	3490
	21st to end	Night	16% 6% 2 6% 4 3 4 3 5% 6% 44%	3688
April	1st to 10th	Night	10% 5% 1 3 3 3 4 4 5% 7% 54%	1900
	11th to 20th	Night	8% 4 1 4 3 4 3 3 5% 6% 61%	1879
	21st to end	Night	5% 2 1 2 2 2 3 3 5% 7% 67%	1900
May	1st to 10th	Night	2 2 1 2 1 2 2 2 3 5% 79%	3133
	11th to 20th	Night	2 1 1 1 1 1 1 2 2 4 85%	2558
	21st to end	Night	1 1 1 1 2 2 1 3 3 84%	2762
June	1st to 10th	Night	3 2 1 3 2 2 2 3 3 6% 73%	1520
	11th to 20th	Night	1 1 1 1 2 1 3 4 86%	1520
	21st to end	Night	1 1 1 1 1 1 2 2 3 86%	1520
July	1st to 10th	Night	1 1 1 1 1 95%	2540
	11th to 20th	Night	1 1 1 1 1 2 1 2 3 85%	2620
	21st to end	Night	1 1 1 1 1 1 1 2 4 87%	3109
August	1st to 10th	Night	2 1 1 2 1 1 2 2 4 4 80%	2848
	11th to 20th	Night	1 1 1 1 1 1 3 90%	3087
	21st to end	Night	2 1 1 1 1 1 1 2 89%	3498
September	1st to 10th	Night	1 1 1 1 1 2 3 90%	1900
	11th to 20th	Night	3 1 2 1 1 2 1 2 4 82%	1900
	21st to end	Night	1 1 1 1 1 1 2 2 3 4 84%	2127
October	1st to 10th	Night	3 2 2 1 2 2 2 2 4 80%	3800
	11th to 20th	Night	2 2 1 2 1 2 1 2 3 5% 78%	3777
	21st to end	Night	5% 2 1 3 2 3 3 3 4 5% 69%	4121
November	1st to 10th	Night	8% 3 1 3 3 2 3 3 5% 8% 62%	2464
	11th to 20th	Night	9% 4 2 4 3 3 3 3 5% 7% 58%	2600
	21st to end	Night	12% 4 1 4 3 3 4 3 4 5% 58%	2710
December	1st to 10th	Night	15% 5% 2 5% 3 3 4 3 5% 6% 50%	2660
	11th to 20th	Night	20% 7% 2 6% 5% 4 4 4 6% 7% 34%	3276
	21st to end	Night	17% 6% 2 9% 6% 6% 6% 3 6% 6% 32%	4862

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	55% 5% 11% 21% 7% 1	2540
	11th to 20th	Day	57% 6% 9% 15% 10% 4	2860
	21st to end	Day	56% 5% 11% 16% 10% 2	3146
February	1st to 10th	Day	42% 5% 8% 23% 15% 6%	1710
	11th to 20th	Day	38% 4 11% 22% 19% 5%	1803
	21st to end	Day	35% 4 10% 25% 20% 5%	1570
March	1st to 10th	Day	47% 9% 11% 16% 15% 2	3262
	11th to 20th	Day	27% 4 12% 30% 16% 11%	3490
	21st to end	Day	39% 8% 15% 24% 12% 3	3964
April	1st to 10th	Day	34% 4 12% 24% 18% 8%	2280
	11th to 20th	Day	26% 5% 12% 27% 23% 7%	2252
	21st to end	Day	19% 4 13% 30% 28% 7%	2280
May	1st to 10th	Day	14% 2 8% 29% 27% 20%	3829
	11th to 20th	Day	9% 2 4 27% 43% 15%	4335
	21st to end	Day	9% 3 9% 32% 34% 12%	4814
June	1st to 10th	Day	15% 4 10% 26% 29% 16%	2660
	11th to 20th	Day	6% 2 6% 21% 36% 27%	2660
	21st to end	Day	7% 1 3 11% 34% 44%	2660
July	1st to 10th	Day	2 1 5% 14% 77%	4351
	11th to 20th	Day	7% 1 3 6% 15% 67%	4264
	21st to end	Day	4 1 1 5% 29% 61%	4315
August	1st to 10th	Day	8% 1 2 7% 25% 56%	4076
	11th to 20th	Day	4 1 2 7% 41% 46%	3798
	21st to end	Day	6% 1 3 10% 37% 43%	4179
September	1st to 10th	Day	5% 1 2 9% 29% 54%	2280
	11th to 20th	Day	10% 1 6% 21% 39% 22%	2280
	21st to end	Day	10% 2 4 19% 37% 29%	2048
October	1st to 10th	Day	10% 2 4 12% 28% 44%	3180
	11th to 20th	Day	14% 3 6% 24% 35% 19%	3161
	21st to end	Day	19% 4 7% 20% 37% 13%	3448
November	1st to 10th	Day	27% 5% 9% 26% 25% 8%	1835
	11th to 20th	Day	33% 6% 12% 25% 20% 4	1800
	21st to end	Day	34% 4 11% 24% 20% 7%	1680
December	1st to 10th	Day	43% 4 12% 19% 15% 6%	1520
	11th to 20th	Day	60% 4 8% 13% 11% 3	1928
	21st to end	Day	51% 9% 16% 14% 9% 2	2794
January	1st to 10th	Night	42% 7% 15% 25% 8% 3	4402
	11th to 20th	Night	51% 6% 13% 14% 9% 6%	4110
	21st to end	Night	51% 6% 13% 15% 11% 4	4521
February	1st to 10th	Night	37% 3 9% 23% 20% 8%	2470
	11th to 20th	Night	31% 5% 10% 24% 24% 7%	2275
	21st to end	Night	32% 4 11% 26% 22% 6%	1884
March	1st to 10th	Night	45% 8% 14% 14% 15% 4	3595
	11th to 20th	Night	29% 4 9% 25% 20% 13%	3490
	21st to end	Night	40% 7% 13% 23% 12% 5%	3688
April	1st to 10th	Night	30% 6% 12% 23% 22% 8%	1900
	11th to 20th	Night	24% 5% 11% 28% 20% 11%	1879
	21st to end	Night	17% 4 14% 30% 29% 7%	1900
May	1st to 10th	Night	11% 3 12% 26% 30% 19%	3133
	11th to 20th	Night	7% 2 6% 25% 41% 19%	2558
	21st to end	Night	8% 3 9% 36% 34% 11%	2762
June	1st to 10th	Night	14% 4 10% 27% 31% 13%	1520
	11th to 20th	Night	5% 2 7% 20% 37% 29%	1520
	21st to end	Night	6% 2 2 13% 31% 45%	1520
July	1st to 10th	Night	2 1 1 5% 15% 77%	2500
	11th to 20th	Night	8% 1 3 5% 16% 66%	2572
	21st to end	Night	5% 1 2 4 26% 62%	3011
August	1st to 10th	Night	9% 2 2 8% 25% 55%	2839
	11th to 20th	Night	4 1 2 7% 37% 49%	3117
	21st to end	Night	6% 1 3 9% 33% 48%	3498
September	1st to 10th	Night	3 1 3 8% 30% 54%	1900
	11th to 20th	Night	10% 3 4 20% 38% 25%	1900
	21st to end	Night	7% 2 4 19% 35% 33%	2127
October	1st to 10th	Night	11% 2 4 10% 20% 53%	3800
	11th to 20th	Night	11% 2 6% 27% 30% 23%	3777
	21st to end	Night	18% 3 5% 20% 33% 20%	4121
November	1st to 10th	Night	23% 4 10% 24% 24% 14%	2464
	11th to 20th	Night	27% 4 10% 26% 26% 8%	2600
	21st to end	Night	29% 4 9% 23% 27% 9%	2710
December	1st to 10th	Night	36% 6% 10% 21% 18% 9%	2660
	11th to 20th	Night	50% 5% 10% 17% 14% 4	3276
	21st to end	Night	49% 9% 13% 17% 9% 3	4862

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	33% 5% 15% 23% 17% 7%	181
	11th to 20th	Day	19% 6% 15% 24% 24% 12%	370
	21st to end	Day	16% 5% 17% 23% 23% 16%	407
February	1st to 10th	Day	18% 8% 15% 20% 21% 18%	370
	11th to 20th	Day	14% 8% 25% 22% 18% 13%	428
	21st to end	Day	13% 10% 20% 25% 24% 9%	382
March	1st to 10th	Day	18% 10% 19% 29% 18% 6%	460
	11th to 20th	Day	18% 9% 19% 23% 20% 12%	460
	21st to end	Day	14% 9% 25% 26% 19% 7%	506
April	1st to 10th	Day	15% 7% 22% 28% 16% 11%	460
	11th to 20th	Day	10% 8% 24% 28% 19% 11%	452
	21st to end	Day	6% 6% 23% 30% 22% 13%	460
May	1st to 10th	Day	5% 7% 27% 30% 22% 9%	463
	11th to 20th	Day	4 5% 25% 27% 27% 11%	488
	21st to end	Day	4 5% 17% 28% 33% 13%	529
June	1st to 10th	Day	3 5% 21% 32% 29% 11%	490
	11th to 20th	Day	1 5% 20% 38% 30% 6%	490
	21st to end	Day	1 2 16% 32% 36% 12%	490
July	1st to 10th	Day	1 1 11% 37% 40% 11%	486
	11th to 20th	Day	1 9% 33% 46% 11%	484
	21st to end	Day	1 8% 38% 40% 13%	531
August	1st to 10th	Day	2 1 12% 37% 35% 12%	487
	11th to 20th	Day	1 1 14% 33% 36% 13%	477
	21st to end	Day	1 1 8% 37% 41% 13%	539
September	1st to 10th	Day	1 2 9% 34% 40% 15%	490
	11th to 20th	Day	2 2 17% 32% 30% 16%	490
	21st to end	Day	2 3 12% 29% 33% 21%	490
October	1st to 10th	Day	2 3 17% 24% 30% 24%	490
	11th to 20th	Day	4 6% 11% 21% 31% 27%	490
	21st to end	Day	7% 5% 13% 23% 32% 20%	539
November	1st to 10th	Day	7% 5% 15% 22% 27% 23%	371
	11th to 20th	Day	9% 4 16% 25% 30% 16%	300
	21st to end	Day	13% 1 13% 28% 32% 13%	242
December	1st to 10th	Day	19% 4 13% 26% 22% 16%	180
	11th to 20th	Day	16% 6% 18% 22% 24% 13%	180
	21st to end	Day	16% 7% 17% 32% 22% 7%	198
January	1st to 10th	Night	18% 5% 15% 33% 24% 5%	760
	11th to 20th	Night	14% 4 13% 38% 26% 5%	760
	21st to end	Night	17% 3 14% 35% 26% 5%	836
February	1st to 10th	Night	19% 4 15% 35% 24% 3	760
	11th to 20th	Night	13% 5% 18% 34% 26% 3	744
	21st to end	Night	13% 5% 21% 40% 18% 3	628
March	1st to 10th	Night	16% 6% 21% 33% 22% 2	760
	11th to 20th	Night	15% 6% 18% 36% 23% 2	760
	21st to end	Night	14% 5% 23% 38% 20% 1	836
April	1st to 10th	Night	11% 4 23% 38% 22% 1	760
	11th to 20th	Night	7% 6% 27% 36% 20% 3	751
	21st to end	Night	5% 3 25% 40% 24% 3	760
May	1st to 10th	Night	3 3 27% 42% 21% 3	739
	11th to 20th	Night	4 1 16% 47% 30% 1	403
	21st to end	Night	3 2 22% 44% 29%	411
June	1st to 10th	Night	4 2 19% 52% 23% 1	380
	11th to 20th	Night	1 1 20% 51% 26%	380
	21st to end	Night	1 13% 54% 31% 1	380
July	1st to 10th	Night	7% 56% 35% 1	370
	11th to 20th	Night	1 8% 52% 38% 1	409
	21st to end	Night	1 4 45% 46% 2	624
August	1st to 10th	Night	1 1 7% 44% 45% 2	567
	11th to 20th	Night	12% 49% 35% 3	725
	21st to end	Night	2 7% 48% 41% 2	836
September	1st to 10th	Night	1 9% 47% 41% 2	760
	11th to 20th	Night	3 2 13% 43% 35% 4	760
	21st to end	Night	2 1 13% 40% 38% 6%	760
October	1st to 10th	Night	4 3 11% 43% 31% 8%	760
	11th to 20th	Night	5% 4 12% 36% 38% 5%	760
	21st to end	Night	5% 4 10% 38% 34% 10%	836
November	1st to 10th	Night	8% 2 13% 37% 32% 7%	780
	11th to 20th	Night	10% 2 12% 42% 30% 4	800
	21st to end	Night	12% 2 14% 37% 30% 5%	800
December	1st to 10th	Night	16% 3 13% 39% 24% 6%	760
	11th to 20th	Night	22% 4 14% 35% 23% 3	760
	21st to end	Night	19% 6% 17% 34% 22% 1	836

Page generated at 2024-11-27 14:30:50. Version ac07

Copyright © 2024 Attilla Danko.