Search results
Results From The WOW.Com Content Network
In meteorology, an okta is a unit of measurement used to describe the amount of cloud cover at any given location such as a weather station. Sky conditions are estimated in terms of how many eighths of the sky are covered in cloud , ranging from 0 oktas (completely clear sky) through to 8 oktas (completely overcast ).
View of clouds from above. The cloud top (or the top of the cloud) is the highest altitude of the visible portion of a cloud.It is traditionally expressed either in metres above the Earth (or planetary) surface, or as the corresponding pressure level in hectopascal (hPa, equivalent to the traditional but now obsolete millibar).
This will give the altitude of the cloud base in feet above ground level. Put in a simpler way, 400 feet for every 1°C dew point spread. For metric divide the spread in °C by 8 and multiply by 1000 and get the cloud base in meters. Add the results from step (2) to the field elevation to obtain the altitude of the cloud base above mean sea level.
The cloud height, more commonly known as cloud thickness or depth, is the distance between the cloud base and the cloud top. [1] It is traditionally expressed either in metres or as a pressure difference in hectopascal (hPa, equivalent to millibar ).
Clouds height can vary depending on latitude; with cloud cover in polar latitudes being slightly lower and in tropical regions the cloud cover may extend up to 8,000m. The type of cloud is also a factor, with low cumulus clouds sitting at 300–1,500m while high cirrus clouds at 5,500-6,500m.
Clouds of the genus nimbostratus tend to bring constant precipitation and low visibility. This cloud type normally forms above 2 kilometres (6,600 ft) [10] from altostratus cloud but tends to thicken into the lower levels during the occurrence of precipitation. The top of a nimbostratus deck is usually in the middle level of the troposphere.
A cap cloud is a special form of the lenticular cloud with a base low enough that it forms around and covers the peak, capping it. [3] A chinook arch cloud is an extensive wave cloud. It has this special name in North America where it is associated with the Chinook wind. It forms above the mountain range, usually at the beginning of a chinook ...
In 2001, Attilla Danko, computer programmer and amateur astronomer, began to summarize Rahill's hundreds of forecast maps by displaying only one pixel, from each map, laid out in rows. [3] The resulting meteogram, called a clear sky chart, showed all of Rahill's forecast data, but for only one location. Danko writes "It shows at a glance when ...