1 to 9 knots

Winds which are changing direction in an anti-clockwise fashion.

Literally 'one or two' during the forecast period.

Upper air patterns are analysed and forecast at these heights.  Wind and height fields at these heights, around 30000ft and 20000ft respectively, are used to establish weather patterns at the surface. [..]

This is the air temperature at around 5000ft (850 hPa)

Literally 'a few' during the forecast period.

A condition that exists where the environmental lapse rate exceeds the dry adiabatic lapse rate

The process of transport of an atmospheric property solely by the mass motion (velocity field) of the atmosphere. Often, particularly in synoptic meteorology, advection refers only to the horizontal o [..]

12 noon to 6pm.

Irregular motion of an aircraft in flight, especially when characterized by rapid up-and-down motion, caused by a rapid variation of atmospheric wind velocities. Usually associated with larger cumulus [..]