# Weather Map (天気図)

> The atmosphere drawn on one sheet with isobars, front symbols and weather signs. Making invisible pressure fields visible through the density of curves became the public's scientific graphic, from newspapers to television.

- IndexStyle No.432 — https://indexstyle.org/styles/weather-map
- Kind: Style · Family: Diagrammatic Expression · Era: 1851–
- Mood: Trust, Technology, Calm
- Color cues: #e9e6dd / #67635d / #171615 (cues taken from reference works, not a fixed palette)

## Defining characteristics

- The density of isobars
- Cold and warm front symbols
- The weather-symbol system
- Highs and lows labeled

## Best used for

- Comparing primary sources and canonical works
- Extracting principles that transfer to other media

## Research method

This entry records a historical style; derive the treatment from its sources rather than a fixed recipe:

- Observe the letters, signs and scale of reference works
- Extract the one structure that governs gaze and information
- Verify the materials and behaviors specific to era, region and process

## What to avoid

Don't reduce it to surface signs. Verify the context of era, region, technology and makers.

## Application checklist

Before calling a piece an application of this style, check it against the defining characteristics:

- [ ] The density of isobars
- [ ] Cold and warm front symbols
- [ ] The weather-symbol system
- [ ] Highs and lows labeled
- [ ] At least one reference work below has been studied directly
- [ ] The caution above ("What to avoid") has been addressed

## Related styles

- **Celestial Atlas (星図の様式)** — The Baroque celestial atlas layering constellation mythology over observation. Cellarius's Harmonia Macrocosmica marks the summit of an age when scientific diagram could also be decorative art. → https://indexstyle.org/styles/celestial-atlas
- **Schematic Transit Diagram (スキーマティック路線図)** — Discards geographic accuracy for horizontal, vertical and 45-degree lines with evenly spaced stations. Beck's 1933 London Underground diagram established it as the common language of transit maps worldwide. → https://indexstyle.org/styles/transit-diagram

## Further study

- FitzRoy's charts
- international weather symbols
- the design history of TV weather maps

## Reference works

- 地上天気図 1947 — https://commons.wikimedia.org/wiki/File:1947%20October%2012%200630%20UTC%20daily%20weather%20map.png
- 『パーフェクト・ストーム』の解析図 1991 — https://commons.wikimedia.org/wiki/File:1991%20perfect%20storm%20weather%20analysis%2C%20October%2031%2C%201991.jpg

## Source of record

- 気象庁 — https://www.jma.go.jp/jma/index.html

## Machine surfaces

- JSON: https://indexstyle.org/api/styles/weather-map
- Image-generation prompt (legally clean): https://indexstyle.org/styles/weather-map/prompt.txt
- MCP: https://indexstyle.org/mcp (tools: search_styles, get_style, compose_styles; prompts: image-prompt, apply-style)

## 日本語

等圧線・前線記号・天気記号で大気を一枚に描く図法。目に見えない気圧の場を曲線の疎密で可視化する手法は、新聞からテレビまで公共の科学グラフィックとして定着した。

特徴: 等圧線の疎密／寒冷・温暖前線の記号／天気記号の体系／高低気圧のラベル
注意: 表面的な記号へ還元せず、時代・地域・技術・制作主体の文脈を確認する。