Weather and Synoptic Charts

A north westerly wind means the wind is coming from

The north west

‘Synoptic’

Summary of current situation

Isobars

Join areas of equal atmospheric pressure

Isobars reveal

Where wind is coming from and how strong it is

Wind blows ___ to isobars

Parallel

How to tell which was wind is blowing with isobars

When yoh stand with your back to the wind, the LOwEST pressure side should be on the LEFT.

In high pressure winds blow…

Clockwise

In high pressure air

Descends

Clouds in high pressure

Limites

High pressure in summer

Warm weather, light wind

Wind direction in low pressure

Anti-clockwise

In low pressure air is

Rising

Process in low pressure

As air rises, it cools, forming clouds and rain

Characteristics of low pressure

Unsettled, wet, windy

In UK a front desperate which air masses

Tropical wet and cold dry

Which front moves faster

Cold

Which front is always higher

Warm

Before the warm front

Thick clouds, rain

Length of band of rain before warm from

200 miles

Which front has rain that lasts longer

Warm

Which front has rain that is heavier

Cold

At a cold front

Narrow rain band, thunder, heavy

After cold front

Clearer, cooler, showers

When warm front passes, wind

Changes in clockwise direction

When cold front passes, wind changes in

Clockwise direction

Occluded frony

Cold catches up with warm front, forcing warm air up

Weather ahead of occluded front is like

Warm front

Weather behind occluded front is like

Cold front

Crosses at edge of occluded front

Show weakening

When occluded front weakens

Less temperature different and showers

Troughs show

Unstable air and shows showers likely

Air moves from ___ to ___ pressure

High to low

High and low pressure control

Air movements (wind, cloud formation)

Cold and warm masses create

Weather changes and precipitation

Low pressure systems spin and draw

Cold air on one side to create cold front and warm air on other side creating warm front.

In summer after high pressure for a prolonged period, humid conditions can be dissipated by

Thunderstorms

Convection

Warm, moisture thermals rise and cool

As warm moist air is forced upwards

High wispy clouds form, then thick cliud

A halo around sun suggests

Moisture in form of ice crystals in atmospherr

Cirrus clouds develop as

Edge of warm air cools