Fifteenth Century -

Ostend Belgium Weather

Belgium Weather / July 1, 2019

The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on September. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.

Average Hourly Temperature in September

The average hourly temperature, color coded into bands: frigid < 15°F < freezing < 32°F < chilly < 45°F < cold < 55°F < cool < 65°F < comfortable < 75°F < warm < 85°F < hot < 95°F < sweltering. The shaded overlays indicate night and civil twilight.

The month of September in Ostend experiences gradually increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 45% to 52%.

The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 55% of the time.

For reference, on December 30, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 68%, while on July 22, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 58%.

Cloud Cover in September

The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Ostend, the chance of a wet day over the course of September is gradually increasing, starting the month at 27% and ending it at 29%.

For reference, the year's highest daily chance of a wet day is 35% on November 23, and its lowest chance is 21% on April 16.

Probability of Precipitation in September

The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).


To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day rainfall during September in Ostend is essentially constant, remaining about 2.0 inches throughout, and rarely exceeding 3.7 inches or falling below 0.5 inches.

Average Monthly Rainfall in September

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average liquid-equivalent snowfall.

Over the course of September in Ostend, the length of the day is rapidly decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 52 minutes, implying an average daily decrease of 3 minutes, 51 seconds, and weekly decrease of 26 minutes, 56 seconds.

The shortest day of the month is September 30, with 11 hours, 41 minutes of daylight and the longest day is September 1, with 13 hours, 32 minutes of daylight.

Hours of Daylight and Twilight in September

The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.

The earliest sunrise of the month in Ostend is 7:01 AM on September 1 and the latest sunrise is 46 minutes later at 7:47 AM on September 30.