The quantity of precipitation is not uniform on the surface of the Earth. On maps the quantity of precipitation at different areas is divided by isohyet
Precipitation is the deposition of water to the Earth's surface, in the form of rain, snow, ice or hail.
All precipitation quantities are expressed in millimetres (mm) of liquid water equivalent for the preceeding time interval (or in inches). One millimetre of rain corresponds to 1 litre per square metre of water on the surface, or approximately 10 millimetres of snow.
We present our best high resolution precipitation forecast in the point meteograms, pictocast, rainSPOT and on the maps.
Other presentations and scales can be supplied on request.
Types
meteoblue forecasts precipitation types in the form of:
rain (liquid),
snow (crystals),
ice (frozen water), ice rain, freezing rain,
dew (condensation on surfaces), for Agro services.
Other precipitation types, such as hail (solid ice) can be calculated for special services.
Convective and stratiform precipitation
Precipitation falls in 3 forms:
Convective precipitation falls as showers with rapidly changing intensity, and over a certain area for a relatively short time, as convective clouds have limited horizontal extent.
Orographic precipitation falls when masses of air pushed by wind are forced up the side of elevated land formations, such as large mountains.
Stratiform precipitation caused by frontal systems (mainly of cold air) that usually bring rain distributed in a uniform way over a larger area.
meteoblue shows precipitation quantities as a total. In the meteograms, precipitation is divided into convective (includes both convective and orographic) in light blue (showers) and total (by adding stratiform precipitation) in dark blue. Convective precipitation is likely to be more erratic, and unevenly distributed than stratiform precipitation, so actual quantities, spatial distribution and probabilities are likely to vary much more compared to average display values than for stratiform precipitation.
Snowfall is shown with "***" and freezing rain as "!". Hail is only displayed for special services. If precipitation falls as snow, the height of the snow cover can be indicated separately - otherwise, multiply the quantity of water by the factor 10 to obtain fresh snow cover.