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The synoptic system was designed to be telegraphed and plotted, not read by the public, and that explains everything about how it looks. A station model compresses a complete observation into a few square centimetres by giving every quantity a reserved position, so nothing needs a label and a forecaster can read a hundred at a glance. Isobar spacing gives the wind before any wind symbol is examined, and front symbols are composed rather than invented — the stationary front is simply the warm and cold notations facing away from each other. Two things are recorded as being softer than they look: a warning colour combines likelihood with impact rather than measuring the weather, so the same rainfall is warned differently in different places; and forecast pictograms on a phone follow no standard whatsoever, which is the opposite of everything else here.
Isobars, fronts, pressure centres and station circles, in one picture.
A circle surrounded by numbers, each position meaning a fixed thing.
How much of the station circle is filled — eighths of the sky.
A capital H or L at the middle of a set of closed isobars.
Triangles on one side, semicircles on the other, pointing opposite ways.
A bold line with no triangles: a pressure feature without a front.
Blue for cold, red for warm, purple for occluded — where colour is available.
Dots for rain, stars for snow, triangles for hail — and doubling means heavier.
Isotherm, isohyet, contour — lines joining equal values of anything.
A skewed thermodynamic diagram that tells a forecaster whether air will rise.
A circle with two curved tails, spiralling the way the storm does.
Blue through red: how hard it is raining, not what kind of weather it is.
Wind force 0 to 12, described by what it does rather than measured.
Smooth, slight, rough, phenomenal — wave height in words.
Imminent, soon, later — and visibility words with exact ranges.
A black cone hoisted point up or point down at a harbour.
Yellow, amber, red — likelihood crossed with impact, not severity alone.
A number from 1 upward, with colour bands and a threshold at 3.
The sun, cloud and raindrop icons — a different system from the chart.