1. Click/scroll to advance, applies to all slides. “PLOTTING SYMBOLS FOR DUMMIES” Images & Graphics courtesy of Arthur Charles & Colin Brenchley.

2. 00 Cloud development not observed/observable during past hour. 01 Clouds generally dissolving during past hour. 02 State of sky unchanged during past hour. 03 Clouds generally forming or developing during past hour. 04 Visibly reduced by smoke. 05 Haze. 06 Dust suspended in the air, but not raised by wind. 07Dust or sand raised by the wind. 08 Dust devils now or within last hour. 09 Duststorm or sandstorm not at station but within sight. 00 – 09 No precipitation, fog, dust storm, sandstorm, drifting or blowing snow at the station at the time of observation or, except for 09 during the preceding hour.

3. 10 - 19 10 Mist. 11 Patches of shallow fog at station, not deeper than 2 m (10 m at sea). 12 Continuous shallow fog at station, not deeper than 2 m (10 m at sea). 13 Lightning visible, but no thunder heard. 14 Precipitation visible but not reaching ground at station. 15 Precipitation reaching the ground not at or near the station but at a distance. 16 Precipitation reaching the ground not at the station but nearby. 17 Thunder heard but no precipitation at the station. 18 Wind squall now or during the past hour. 19 Tornado, waterspout or funnel cloud observed now or during the past hour. No precipitation at the station at the time of observation or, except 17, during the preceding hour.

4. 20 - 29 20 Recent drizzle (not freezing, not showers) during past hour. 21 Recent rain (not freezing, not showers) during past hour. 22 Recent snow (not showers) during past hour. 23 Recent rain and snow (not showers) during past hour. 24 Freezing drizzle or rain (not showers), not now but during the past hour. 25 Rain showers, not now but during the past hour. 26 Snow showers, not now but during the past hour. 27 Hail or hail and rain, not now but during the past hour. 28 Fog, not now but during the past hour. 29 Thunderstorms, with or without precipitation, not now but during the past hour. Precipitation, fog, ice fog, or thunderstorm at the station during the preceding hour but not at the time of observation.

5. 30 - 39 30 Slight/moderate duststorm or sandstorm, decreased during the hour. 31 Slight/moderate duststorm or sandstorm, no change during the hour. 32 Slight/moderate duststorm or sandstorm, increased during the hour. 33 Severe duststorm or sandstorm, which has decreased during the hour. 34 Severe duststorm or sandstorm, no change during past hour. 35 Severe duststorm or sandstorm, has increased during past hour. 36 Drifting snow, slight or moderate. 37 Drifting snow, heavy. 38 Blowing snow, light or moderate. 39 Blowing snow, heavy. Dust storm, sandstorm, drifting or blowing snow.

6. 40 - 49 40 Fog at a distance but not at station during past hour. 41 Patchy fog. 42 Fog, sky visible, and has become thinner during past hour. 43 Fog, sky not visible, and has become thinner during past hour. 44 Fog, sky visible, no change during past hour. 45 Fog, sky not visible, no change during past hour. 46 Fog, sky visible, has begun or become thicker during past hour. 47Fog, sky not visible, has begun or becoming thicker during past hour. 48 Freezing fog, sky visible. 49 Freezing fog, sky not visible. Fog at the time of observation.

7. 50 - 59 50 Drizzle, light, intermittent, not freezing. 51 Drizzle, light, continuous, not freezing. 52 Drizzle, moderate, intermittent, not freezing. 53 Drizzle, moderate, continuous, not freezing. 54 Drizzle, heavy, intermittent, not freezing. 55 Drizzle, heavy, continuous, not freezing. 56 Freezing drizzle, light. 57 Freezing drizzle, moderate or heavy. 58 Drizzle and rain mixed, light. 59 Drizzle and rain mixed, moderate or heavy. Drizzle.

8. 60 - 69 Rain. 60 Rain, light, intermittent, not freezing. 61Rain, light continuous, not freezing. 62Rain, moderate, intermittent, not freezing. 63Rain, moderate, continuous, not freezing. 64 Rain, heavy, intermittent, not freezing. 65 Rain, heavy, continuous, not freezing. 66 Freezing rain, light. 67 Freezing rain, moderate or heavy 68 Rain and snow mixed, light. 69 Rain and snow mixed, moderate or heavy.

9. 70 - 79 Solid precipitation not in showers. 70 Snow, light, intermittent. 71 Snow, light, continuous. 72 Snow, moderate, intermittent. 73Snow, moderate, continuous. 74 Snow, heavy, intermittent. 75Snow, heavy, continuous. 76Ice needles, with or without fog. 77Snow grains, with or without fog. 78Snow crystals, with or without fog. 79Ice pellets (sleet).

10. 80 – 89 Showery precipitation, or precipitation with current or recent thunderstorm. 80 Rain showers, light. 81 Rain showers, moderate or heavy. 82 Rain showers, torrential. 83 Rain/snow showers mixed, light. 84Rain/snow showers mixed, moderate or heavy. 85Snow showers, light. 86Snow showers, moderate or heavy. 87Ice pellet showers, light. 88 Ice pellets showers, moderate or heavy. 89 Hail, light, not associated with thunder.

11. 90 - 99 continued...Showery precipitation, or precipitation with current or recent thunderstorm. 90 Hail, moderate or heavy, not associated with thunder. 91 Rain, light. Thunder heard during past hour but not now. 92 Rain, moderate or heavy. Thunder heard during past hour but now. 93 Light snow or rain/snow mixed with hail. Thunder heard during past hour. 94Moderate or heavy snow or rain/snow with hail. Thunder heard during past hour. 95 Thunderstorm, light or moderate, rain or snow, but no hail. 96 Thunderstorm, light or moderate with hail. 97Thunderstorm, severe, rain or snow but no hail. 98Thunderstorm, with duststorm or sandstorm. 99Thunderstorm, severe, with hail.

12. N = TOTAL CLOUD COVER 0 No Cloud. 1 1/8 th or 1/10 th Cloud Cover. 22/8 ths or 2 to 3 tenths Cloud Cover. 3 3/8 ths or 4 tenths Cloud Cover. 44/8 ths or 5 tenths Cloud Cover. 55/8 ths or 6 tenths Cloud Cover. 66/8 ths or 7 to 8 tenths Cloud Cover. 77/8 ths or 9 tenths Cloud Cover. 8 8/8 ths Skycover (completely overcast). 9Sky Obscured (used when a surface-based weather phenomena (i.e. fog, dust, etc. blocks the view of the sky).

13. W = PAST WEATHER 0 Cloud covering half or less of the sky throughout period. 1Cloud covering both more than half and less than half of sky during period. 2Cloud covering more than half of sky throughout period. 3Sandstorm, or duststorm, or drifting or blowing snow. 4Fog or thick haze. 5Drizzle. 6Rain. 7Snow. 8Showers. 9Thunderstorm, with or without precipitation.

14. a = PRESSURE TENDENCY 0Rising then falling. 1Rising, then steady; or rising, then rising more slowly. 2Rising, steadily or unsteadily. 3Falling or steady, then rising; or rising then rising more rapidly. 4Steady. 5Falling, then rising. 6Falling, then steady; or falling, then falling more slowly. 7Falling, steadily or unsteadily. 8Steady or rising, then falling; or falling, then falling more rapidly.

15. = C L = LOW CLOUDS L1CUMULUS, with little vertical development and seemingly flattened. L2CUMULUS, of considerable size. Towering cumulus. L3CUMULOSNIMBUS, tops are not fibrous, cirriform or anvil shape. L4STRATOCUMULUS, formed by the spreading out of cumulus. L5STRATOCUMULUS, not formed by the spreading out of cumulus. L6STRATUS, in continuous layers or shreds. No stratus of bad weather. L7STRATUS, of bad weather(scud) and often with nimbostratus. L8STRATOCUMULUS AND CUMULUS with basis at different levels and not formed by spreading Cu. L9CUMULONIMBUS, whose tops are clearly fibrous or anvil shaped.

16. C M = MID CLOUDS M2ALTOSTRATUS or NIMBOSTRATUS. The sun/moon can’t be seen. M3ALTOCUMULUS, at single level and semitransparent. M4ALTOCUMULUS, in patches, continuously changing. M5ALTOCUMULUS, invading sky and usually thickening. M6ALTOCUMULUS, formed by spreading out of cumulus. M7ALTOCUMULUS, not invading sky, usually double-layered/opaque. M8ALTOCUMULUS, in the form of cumuliform tufts (castellanus). M9ALTOCUMULUS, at many layers (a chaotic sky). M1ALTOSTRATUS, semitransparent, thin enough to see sun/moon.

17. H4CIRRUS, in the form of hooks or filaments invading the sky. H2CIRRUS, dense and in patches/twisted sheaves, not invading the sky. C H = HIGH CLOUDS H5CIRRUS or CIRROSTRATUS, invading sky, bulk not 45º above horizon. H6CIRRUS or CIRROSTRATUS, invading the sky, bulk 45º or more above horizon. H7CIRROSTRATUS, completely covering the sky. H8CIRROSTRATUS, not invading the sky and not covering the sky. H9CIRROCUMULUS, predominating other cirriform clouds. H1CIRRUS, in the form of filaments or hooks, not invading the sky. H3CIRRUS, often anvil shaped and associated with cumulonimbus.

18. Wind Speed & Direction Wind speed. A combination of long/short barbs and pennants indicate the speed of the wind in station weather plots rounded to the nearest 5 knots. Calm wind is indicated by a large circle drawn around the skycover symbol. One long barb is used to indicate each 10 knots with the short barb representing 5 knots. At 50 knots, the barbs changes to a pennant. For wind speeds higher than 50 knots, long and short barbs are used again in combination with the pennant(s). (See examples below.) 28-32 kts (32-37 mph ) 23-27 kts (26-31 mph) 18-22 kts (21-25 mph) 13-17 kts (15-20 mph) 8-12 kts (9-14 mph) 3-7 kts (3-8 mph ) Observed wind speed 33-37 kts (38-43 mph) 48-52 kts (55-60 mph) 53-57 kts (61-66 mph) 58-62 kts (67-71 mph) 63-67 kts (73-77 mph) 98-102 kts (113- 117 mph) 102- 107 kts (119- 123 mph) Rounded to the nearest 5 0-2 kts (0-2 mph 0 kts 5 kts10 kts15 kts20 kts25 kts30 kts35 kts50 kts55 kts60 kts65 kts100 kts105 kts Plotted as Wind FROM 340° (NNW) Wind FROM 040° (NE) Wind FROM 190° (S)

19. This presentation compiled by ‘Team Cloud Observers’ CB, AWC, PJS & MIS on behalf of Cloud Observers ©2011 Source:Various Internet Sites