Weather In Ekeren and Port of Antwerp

• The air that makes up our atmosphere exerts a pressure on the surface of the earth. This pressure is known as atmospheric pressure. Generally, the more air above an area, the higher the atmospheric pressure. Barometric pressure changes with local weather conditions, making barometric pressure an important and useful weather forecasting tool. High pressure zones are generally associated with fair weather, while low pressure zones are generally associated with poor weather. For forecasting purposes, the absolute barometric pressure value is generally less important than the change in barometric pressure. In general, rising pressure indicates improving weather conditions, while falling pressure indicates deteriorating weather conditions.

  Wikipedia: Atmospheric/Barometric Pressure

• A measure of the health risk due to various combinations of high temperature and humidity. The higher the number, the greater the possibility of heat exhaustion or heat stroke.

  Wikipedia: Apparent Temperature

• First used in the early nineteenth century by the British Navy. For every number on the scale, there is a descriptive term such as light air, strong breeze, fresh gale, etc.

  Wikipedia: Beaufort Wind Scale

• The cloud height on this site is an estimate of cumulus clouds using a formula based on temperature and dew point. Actual measurements of cloud height are made with a ceilometer. This device fires a laser into the sky and measures the backscattered signal. Costs for such a device are beyond the scope of weather hobbyists.

• The circulatory motion that occurs at nonuniform temperatures due to gravity and density variation, resulting in the transfer of heat.

  Wikipedia: Atmospheric/Barometric Pressure

• The output of a solar radiation sensor based on a given input. The absorption of radiation is proportional to the cosine of the angle between an oblique ray and one that strikes perpendicularly.

• A measure of the departure of the mean daily temperature above or below a given standard. A ten-degree difference for one day equals ten degree days, as does a one-degree difference for ten days.

  Wikipedia: Degree Day

• A measure of humidity stated in terms of the temperature at which the air would be saturated and dew would begin to form if the amount of water vapor in the air were held constant. The dew point is an important measurement used to predict the formation of dew, frost, and fog. If dew point and temperature are close together in the late afternoon when the air begins to turn colder, fog is likely during the night. Dew point is also a good indicator of the air's actual water vapor content, unlike relative humidity, which takes the air's temperature into account. High dew point indicates high vapor content; low dew point indicates low vapor content. In addition a high dew point indicates a better chance of rain and severe thunderstorms. You can even use dew point to predict the minimum overnight temperature. Provided no fronts or other weather pattern changes are expected overnight, the afternoon's dew point gives you an idea of what minimum temperature to expect overnight.

  Wikipedia: Dew Point

• The range of wavelengths of light responsible for erythema, which is the reddening of the skin due to capillary congestion. Sunburn is among the most common forms of erythema.

• The amount of water transferred from the earth to the atmosphere due to the combined effects of evaporation and transpiration. Transpiration is the process by which plants release water vapor into the air.

  Wikipedia: EvapoTranspiration

• Made of supercooled raindrops. The rain falls in liquid form but freezes when it hits the ground or an exposed object, creating a coating of ice known as glaze.

  Wikipedia: Freezing Rain

• Hectopascal, a measurement of barometric pressure. One hPA equals 100 pascals or one millibar. One pascal is equal to a force of one newton over an area of one square meter.

  Wikipedia: Hectopascal

• The Heat Index is a measure of relative discomfort due to combined heat and high humidity. It was developed by R.G. Steadman (1979) and is based on physiological studies of evaporative skin cooling for various combinations of ambient temperature and humidity. As temperatures climb above 90 °F and humidity goes above 40 percent, conditions are ripe for heat-related illnesses.

  Wikipedia: Heat Index

• Humidity or relative humidity measures the amount of water vapor in the air relative to the temperature. It is important in weather because humidity affects how humans feel. A hot, humid day feels hotter because we cannot sweat as effectively. A cool, dry day feels colder because moisure evaporates more easily.

  Wikipedia: Humidity

• Joules per square centimeter, a measurement of solar energy. A joule is the unit of energy in the meter-kilogram-second system of units, equal to 10⁷ ergs or approximately 0.7375 foot-pounds.

• Crop coefficient, available from local agricultural advisory services. To find the evapotranspiration for a given crop, multiply the reference evapotranspiration by the K-factor.

  Wikipedia: K-Factor

• Langley (Ly) is a measurement of solar energy. One langley is equal to one gram-calorie per square centimeter. A gram-calorie is the amount of heat required to raise the temperature of one gram of water one degree Celsius.

  Wikipedia: Langley (unit)

• Millibar, a unit of pressure equal to one-thousandths of a bar. One bar equals 10⁵ pascals, 10⁵ newtons per square meter, or 10⁶ dynes per square centimeter. One millibar equals one hectopascal.

  Wikipedia: MilliBar (unit)

• Minimal erythemal dose (MDE), a measurement of UV dose. Erythema is the reddening of the skin due to capillary congestion. Sunburn is among the most common forms of erythema.

  Wikipedia: Sunburn

• The energy transmitted from the sun in form of electromagnetic radiation, measured in langleys (Ly).

  Wikipedia: Solar Energy

• The electromagnetic radiation emitted by the sun. Solar radiation sensors actually measure incident solar radiation or solar irradiance, which is the amount of radiant power per unit area that flows across or onto a surface.

  Wikipedia: Solar Radiation

• Ultraviolet spectrum: The range of wavelengths from 4 to 400 nanometers, beginning at the limit of visible light and overlapping the wavelengths of long x-rays.
• The Ultraviolet index is an international standard measurement of how strong the ultraviolet (UV) radiation from the sun is at a particular place on a particular day. It is a scale primarily used in daily forecasts aimed at the general public.

  Wikipedia: UV Index

• Watts per square meter, a measurement of solar radiation. One watt is equal to 0.143 Kg-calories/minute or 1 volt-ampere.

  Wikipedia: Solar Radiation

• The combination of temperature and wind speed. When the wind is blowing, it carries away the air that has been warmed by your body. The wind chill temperature is what the temperature "feels like" to people and animals during cold weather. Wind chill is based on the rate of heat loss from exposed skin caused by wind and cold. As the wind increases, it draws heat from the body, driving down skin temperature and eventually the internal body temperature. It feels as if the temperature is lower than it really is. Once temperatures drop below -12°C (10°F) and the wind is gusting, conditions are ripe for cold-related illnesses. Below -20°C (-5°F), any wind is a major factor in frostbite and hypothermia.

  Wikipedia: Wind Chill

• Calculated by multiplying the wind speed by the measurement period and summing over time. If the wind speed was a constant 10 kilometers per hour for three hours, the wind run would equal 30 kilometers.

• Acroymn for METeorological Aerodrome Report. It is the primary observation code used in the World to satisfy requirements for reporting surface meteorological data. Minimum reporting requirments includes wind, visibility, runway visual range, present weather, sky condition, temperature, dew point, and altimeter setting.
• Antwerp International Airport (EBAW) is this site's primary METAR.

  Wikipedia: Metar

• MesoMap is a combination of the terms "mesonet" and "map".
• In meteorology, "mesonet" is a network of weather stations used to monitor weather over a regional area. Such stations gather data like temperature, pressure, humidity, wind speed/direction, cloud conditions, and precipitation.
• A "map" is a graphical representation of some area.
• Thus, a weather MesoMap is a graphical representation of observing stations (usually surface stations) designed to display regional scale weather information. This allows an observer to gain a perspective of weather phenomena otherwise unobtainable.

• A weather station is a facility with instruments and equipment to make weather observations by monitoring atmospheric conditions to study the weather. This weather station has a thermometer for measuring temperature; barometer for measuring changes in air pressure; hygrometer for measuring humidity; anemometer for measuring wind speed and wind direction; and rain gauge for measuring precipitation. Our station also has non-traditional equipment like a webcam for visual weather observation and an electro-magnetic pulse counter for lightning detection.
• For additional information on Weather Station
• For additional information on Wikipedia: Thermometer
• For additional information on Wikipedia: Anemometer
• For additional information on Wikipedia: Hygrometer
• For additional information on Wikipedia: Rain Gauge

• The agency of the United Nations that is responsible for the international exchange of weather data. It certifies that the data observation procedures do not vary among the over 130 participating nations.

  World Meteorological Organization