The World Association Forecast Centre is a meteorological centre designated to prepare and issue significant weather forecasts only.

The World Association Forecast Centre is a meteorological centre which also provides advisory information on the position, forecast direction and speed of movement of tropical cyclones.

The World Area Forecast Community is a meteorological centre designated to provide advisory information redarding the lateral and vertical extent and forecast movement of volcanic ash in the atmosphere.

The World Area Forecast Centre is a meteorological centre designated to prepare and issue significant weather forecasts and upper-air forecasts.

(5) lightning; (3) gust front; (1) windshear.

(3) severe windshear; (5) windshear.

(1) lightning: (4) gust front; (3) windshear.

(3) no wind; (5) windshear; (1) lightning.

Mountain obstruction

Advection fog.

Valley inversion

Valley winds.

(5) lightning; (3) gust front; (1) windshear.

(3) severe windshear; (5) windshear.

(1) lightning: (4) gust front; (3) windshear.

(3) no wind; (5) windshear; (1) lightning.

cloud-to-cloud.

Cloud-to-ground.

Intra cloud.

Cloud-to-Air.

surface analysis chart.

wind and temperature chart.

contour line chart with isohypses.

significant weather chart.

065°(T)/45 kt

245°(T)/45 kt

275°(T)/45 kt

095°(T)/45 kt

Mountain waves, resulting in downdrafts in excess of the climb performance of most turbojet-engined aeroplanes.

Updrafts and downdrafts, turbulence, and wind shear with changes of wind speed and wind direction.

Severe turbulence at all altitudes up to the tropopause.

Relatively smooth conditions close to the ground, unless a mountain wave exists, or the mountains are steep-sided and irregular.

2,3 and 1

5,6 and 2,3

2,3 and 5,6

4 and 5,6

cyclone

tornado.

dust devil.

funnel-cloud.