MetGlyphs

A small libary which bundles sets of weather glyphs/icons/symbols with useful code to convert between image types for data visualisation and plotting.

When retrieving data from the multitude of weather APIs that are available you often get the weather represented by a code, however the codes are often inconsistent between services. This package allows you to simply convert the codes into glyphs/icons/symbols for use in your plots or applications.

Getting started

pip install metglyphs

# Import the GlyphSet constructor
from metglyphs import GlyphSet

# Create a new set object
glyphs = GlyphSet()

# Get a glyph for a given weather code
glyph = glyphs.get_glyph(datapoint_code="10")

A glyph object can provide an SVG byte string, PNG byte string, or NumPy array of RGB values for you to use however you like.

# SVG
glyph.to_svg()

# PNG
glyph.to_png()

# NumPy array
glyph.to_np_array()

Supported services

This library currently supports the following weather codes.

Provider	Example
Met Office Datapoint	GlyphSet().get_glyph(datapoint_code=<code>)

Glyph sets

All glyphs/symbols/icons bundled in this library are open source and free to use provided you adhere to the terms of their respective licenses.

To use them import the constant for the set you want and then pass it to your GlyphSet object when you construct it.

from metglyphs import GlyphSet
from metglyphs.glyphs import DEFAULT_GLYPHS

glyphs = GlyphSet(name=DEFAULT_GLYPHS)

Set Name	Constant	Provider	Colour type	Colours	License
Met Office	MET_OFFICE_GLYPHS (also DEFAULT_GLYPHS)	Met Office	Full colour	TBC	None
yr.no	YRNO_GLYPHS	yr.no (NRK and MET Norway)	Full colour	TBC	MIT
weathericons.io	WEATHER_ICONS_IO_GLYPHS	Eric Flowers	Monochrome	#9150a1	SIL OFL 1.1

Code reference

A combined subset of the WMO 4677 and WMO 4680 code references is used by this library. This creates a common translation layer between data APIs and glyph sets.

Despite these codes being detailed they were designed for recording observations from manned and unmanned sites respectively. Therefore it is still not always obvious which glyph represents which code, so along with the official description of the code I have included a simple description and glyph suggestion which explains how I have interpreted it.

Day Code	Night Code	Original set	Official Description	Simple Description	Suggested symbol
00d	00n	WMO 4677	Cloud development not observed or not observable	No clouds, clear blue sky	Sun/moon
01d	01n	WMO 4680	Clouds generally dissolving or becoming less developed	Partial cloud with clear breaks	Cloud with sun/moon
03d	03n	WMO 4680	Clouds forming or developing	Cloudy	Light cloud
10d	10n	WMO 4680	Mist	Mist	Cloud with bars or word mist
14d	14n	WMO 4677	Precipitation within sight, not reaching the ground or the surface of the sea	Dark clouds, precipitation* imminent but not falling yet	Dark cloud
18d	18n	WMO 4680	Squalls	Wind	Wind lines
30d	30n	WMO 4680	Fog	Fog	Cloud with bars or word fog
50d	50n	WMO 4680	Drizzle	Drizzle	Cloud with small rain drops
60d	60n	WMO 4680	Rain	Rain	Cloud with rain drops
63d	63n	WMO 4680	Rain, not freezing - heavy	Heavy rain	Cloud with big/many rain drops
65d	65n	WMO 4680	Freezing rain - moderate	Sleet	Cloud with rain drop and ice
70d	70n	WMO 4680	Snow	Snow	Cloud with snowflake
75d	75n	WMO 4680	Ice Pellets - moderate	Hail	Cloud with hail stones
81d	81n	WMO 4680	Intermittent rain - slight	Light rain showers	Cloud with sun/moon and rain drop
83d	83n	WMO 4680	Intermittent rain - heavy	Heavy rain showers	Cloud with sun/moon and multiple rain drops
85d	85n	WMO 4680	Intermittent snow - slight	Light snow showers	Cloud with sun/moon and snow flake
87d	87n	WMO 4680	Intermittent snow - heavy	Heavy snow showers	Cloud with sun/moon and multiple snow flakes
89d	89n	WMO 4680	Hail	Hail showers	Cloud with sun/moon and hail stone
90d	90n	WMO 4680	Thunderstorm	Thunderstorm without rain	Dark cloud with lightening bolt
95d	95n	WMO 4680	Thunderstorm, heavy - rain/snow showers	Thunderstorm with rain showers	Dark cloud with sun/moon, ligitening bolt and rain drop

*precipitation = rain, sleet, snow, hail, etc

All glyph sets should provide a symbol for every code, even if they are duplicated (e.g a dark cloud for 14d and 14n). Data providers will most likely use a subset of codes and therefore a subset of symbols.

Changing colours

It is possible to recolour your glyph sets. You can do this by providing the recolor kwarg in GlyphSet or GlyphSet.get_glyph with a dictionary in the format of {"old hex value": "new hex value"}. Some sets are monochrome and so you only need to change one colour, others are full colour and you should be able to change individual colours to your liking. See the table of sets above for information on which colours to replace.

For example

# This will replace blue with green in all glyphs in this set
glyphs = GlyphSet(recolor={"#0000FF", "#00FF00"})

# This will change the thunder glyph to red
# (note that we are still replacing blue as recoloring is done at render time)
thunder_glyph = glyphs.get_glyph(datapoint_code='30', recolor={"#0000FF", "#FF0000"}

Useful links from Chris Little

https://external.opengeospatial.org/twiki_public/MetOceanDWG/WebHome https://external.opengeospatial.org/twiki_public/MetOceanDWG/WMOandICAOstyles https://github.com/OGCMetOceanDWG/WorldWeatherSymbols http://artefacts.ceda.ac.uk/badc_datadocs/surface/code.html http://codes.wmo.int/