the fall on November 4.

Daily Sunrise & Sunset with Twilight and Daylight Savings Time

The solar day over the course of the year 2012 . From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (solar, civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray. The transitions to and from daylight savings time are indicated by the "DST" labels.

Clouds

The median cloud cover ranges from 25% (mostly clear) to 44% (partly cloudy). The sky is cloudiest on January 8 and clearest on November 11. The clearer part of the year begins around March 18. The cloudier part of the year begins around December 9.

Median Cloud Cover

The median daily cloudcover (black line) with percentile bands (inner band from 40th to 60th percentile, outer band from 25th to 75th percentile).

On November 11, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy68% of the time, and overcast or mostly cloudy32% of the time.

On January 8, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy51% of the time, and clear or mostly clear49% of the time.

Cloud Cover Types

The fraction of time spent in each of the five sky cover categories. From top (most blue) to bottom (most gray), the categories are clear, mostly clear, partly cloudy, mostly cloudy, and overcast. Pink indicates missing data. Outside of the United States clear skies are often reported ambiguously, leading them to