免费、稳定的天气预报API

1. 国家气象局

1. 实时接口：
   实时天气1：http://www.weather.com.cn/data/sk/101190408.html
   实时天气2：http://www.weather.com.cn/data/cityinfo/101190408.html
   实时天气3（带时间戳）：http://mobile.weather.com.cn/data/sk/101010100.html?_=1381891661455

2. 一周天气预报接口
   7天预报数据 URL： http://mobile.weather.com.cn/data/forecast/101010100.html?_=1381891660081
   该接口来源气象局移动版网站，json数据格式如下：

{
    "c": {
        "c1": "101010100", 
        "c2": "beijing", 
        "c3": "北京", 
        "c4": "beijing", 
        "c5": "北京", 
        "c6": "beijing", 
        "c7": "北京", 
        "c8": "china", 
        "c9": "中国", 
        "c10": "1", 
        "c11": "010", 
        "c12": "100000", 
        "c13": "116.391", 
        "c14": "39.904", 
        "c15": "33", 
        "c16": "AZ9010", 
        "c17": "+8"
    }, 
    "f": {
        "f1": [
            {
                "fa": "01", 
                "fb": "03", 
                "fc": "10", 
                "fd": "5", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:21|17:40"
            }, 
            {
                "fa": "07", 
                "fb": "07", 
                "fc": "19", 
                "fd": "12", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:22|17:38"
            }, 
            {
                "fa": "02", 
                "fb": "00", 
                "fc": "15", 
                "fd": "5", 
                "fe": "8", 
                "ff": "8", 
                "fg": "3", 
                "fh": "1", 
                "fi": "06:23|17:37"
            }, 
            {
                "fa": "00", 
                "fb": "00", 
                "fc": "16", 
                "fd": "4", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:24|17:35"
            }, 
            {
                "fa": "00", 
                "fb": "00", 
                "fc": "18", 
                "fd": "7", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:25|17:34"
            }, 
            {
                "fa": "00", 
                "fb": "01", 
                "fc": "18", 
                "fd": "8", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:26|17:32"
            }, 
            {
                "fa": "01", 
                "fb": "01", 
                "fc": "16", 
                "fd": "6", 
                "fe": "0", 
                "ff": "0", 
                "fg": "0", 
                "fh": "0", 
                "fi": "06:27|17:31"
            }
        ], 
        "f0": "201310121100"
    }
}

详细接口分析如下：

//格式说明 
var format={"fa":图片1,"fb"：图片2,"fc":温度1,fd：温度2,fe:风向1,ff：风向2,fg:风力1,fh：风力2,fi:日出日落}; 
//定义天气类型
var weatherArr={
    "10": "暴雨", 
    "11": "大暴雨", 
    "12": "特大暴雨", 
    "13": "阵雪", 
    "14": "小雪", 
    "15": "中雪", 
    "16": "大雪", 
    "17": "暴雪", 
    "18": "雾", 
    "19": "冻雨", 
    "20": "沙尘暴", 
    "21": "小到中雨", 
    "22": "中到大雨", 
    "23": "大到暴雨", 
    "24": "暴雨到大暴雨", 
    "25": "大暴雨到特大暴雨", 
    "26": "小到中雪", 
    "27": "中到大雪", 
    "28": "大到暴雪", 
    "29": "浮尘", 
    "30": "扬沙", 
    "31": "强沙尘暴", 
    "53": "霾", 
    "99": "", 
    "00": "晴", 
    "01": "多云", 
    "02": "阴", 
    "03": "阵雨", 
    "04": "雷阵雨", 
    "05": "雷阵雨伴有冰雹", 
    "06": "雨夹雪", 
    "07": "小雨", 
    "08": "中雨", 
    "09": "大雨"
}; 
//定义风向数组 
var fxArr={
    "0": "无持续风向", 
    "1": "东北风", 
    "2": "东风", 
    "3": "东南风", 
    "4": "南风", 
    "5": "西南风", 
    "6": "西风", 
    "7": "西北风", 
    "8": "北风", 
    "9": "旋转风"
};
//定义风力数组 
var flArr={
    "0": "微风", 
    "1": "3-4级", 
    "2": "4-5级", 
    "3": "5-6级", 
    "4": "6-7级", 
    "5": "7-8级", 
    "6": "8-9级", 
    "7": "9-10级", 
    "8": "10-11级", 
    "9": "11-12级"
};

3. 获取全国所有城市代码列表
   方法一：XML接口根节点： http://flash.weather.com.cn/wmaps/xml/china.xmlXML接口主要作用是递归获取全国几千个县以上单位的城市代码，如：江苏的XML地址为：http://flash.weather.com.cn/wmaps/xml/shanghai.xml 苏州的XML地址为：http://flash.weather.com.cn/wmaps/xml/jiangsu.xml上面页面获得太仓city code：101190408合成太仓天气信息地址：http://m.weather.com.cn/data/101190408.html
   下面贴一段PHP代码实现的，通过XML接口根节点递归获得全国几千个县以上城市cide code的代码，供参考(可直接在终端下运行）：
   方法二：一次性获取全国+国外主要城市，8763个城市列表信息。URL：http://mobile.weather.com.cn/js/citylist.xml

2. 中国天气SmartWeatherAPI(http://smart.weather.com.cn/wzfw/smart/weatherapi.shtml)

1. SmartWeatherAPI接口(简称”SWA”接口)是中国气象局面向网络媒体、手机厂商、第三方气象服务机构等用户，通过web方式提供数据气象服务的官方载体。该数据主要包括预警、实况、指数、常规预报(24小时)等数据内容。
2. 接口文档：http://download.weather.com.cn/creative/SmartWeatherAPI_Lite_WebAPI_3.0.1.rar
3. 使用须申请，详见官网http://smart.weather.com.cn/wzfw/smart/weatherapi.shtml

3. 和风天气

1. 数据主要包含：实时天气，3天内天气预报，生活指数，空气质量。
   访问流量：4000次/天。
   访问频率：200次/分钟。
2. URL：https://free-api.heweather.com/v5/forecast?city=yourcity&key=yourkey
   city：城市名称，city可通过城市中英文名称、ID、IP和经纬度进行查询，经纬度查询格式为：经度,纬度。例：city=北京，city=beijing，city=CN101010100，city= 60.194.130.1
   key：用户认证key
3. 注册页面：https://www.heweather.com/products
   接口文档：https://www.heweather.com/documents/api/v5

4. 心知天气（免费版只提供地级市数据）

1. 包含数据：中国地级城市、天气实况、天气预报（3天）、生活指数（基础）。
   访问频率限制：400次/小时
2. api详述：https://www.seniverse.com/doc
3. 使用需注册。
   注册地址：https://www.seniverse.com/signup

5. 彩云天气

1. 数据包含：实时天气数据（天气、温度、湿度、风向、网速、云量、降雨量、PM2.5、空气质量指数）。
2. API详述：http://wiki.swarma.net/index.php/%E5%BD%A9%E4%BA%91%E5%A4%A9%E6%B0%94API/v2
   url示例：https://api.caiyunapp.com/v2/TAkhjf8d1nlSlspN/121.6544,25.1552/realtime.json
   https://api.caiyunapp.com/v2/TAkhjf8d1nlSlspN/121.6544,25.1552/realtime.jsonp?callback=MYCALLBACK
3. 使用需注册
   产品详单：http://labs.swarma.net/api/caiyun_api_service_price.pdf
   注册页面：https://www.caiyunapp.com/dev_center/regist.html

6. 中央天气预报

1. url：http://tj.nineton.cn/Heart/index/all
   参数如下：
     city：城市码
     language：固定值 zh-chs
     unit：温度单位固定值 c。可不填。也可省略该参数
     aqi：固定值 city。可不填。也可省略该参数
     alarm：固定值 1。可不填。也可省略该参数
     key：秘钥，固定值 78928e706123c1a8f1766f062bc8676b。可不填。也可省略该参数
   url 示例：http://tj.nineton.cn/Heart/index/all?city=CHSH000000&language=zh-chs&unit=c&aqi=city&alarm=1&key=78928e706123c1a8f1766f062bc8676b 或 http://tj.nineton.cn/Heart/index/all?city=CHSH000000&language=&unit=&aqi=&alarm=&key= 或 http://tj.nineton.cn/Heart/index/all?city=CHSH000000
   json 示例：

{
  "status": "OK",
  "weather": [
    {
      "city_name": "佛山",
      "city_id": "CHGD070000",
      "last_update": "2017-02-19T12:15:00+08:00",
      "now": {
        "text": "阴",
        "code": "9",
        "temperature": "21",
        "feels_like": "21",
        "wind_direction": "南",
        "wind_speed": "10.44",
        "wind_scale": "2",
        "humidity": "58",
        "visibility": "13.8",
        "pressure": "1014",
        "pressure_rising": "未知",
        "air_quality": {
          "city": {
            "aqi": "64",
            "pm25": "46",
            "pm10": "74",
            "so2": "9",
            "no2": "28",
            "co": "0.575",
            "o3": "108",
            "last_update": "2017-02-19T12:00:00+08:00",
            "quality": "良"
          },
          "stations": null
        }
      },
      "today": {
        "sunrise": "06:58 AM",
        "sunset": "6:27 PM",
        "suggestion": {
          "dressing": {
            "brief": "单衣类",
            "details": "建议着长袖T恤、衬衫加单裤等服装。年老体弱者宜着针织长袖衬衫、马甲和长裤。"
          },
          "uv": {
            "brief": "最弱",
            "details": "属弱紫外线辐射天气，无需特别防护。若长期在户外，建议涂擦SPF在8-12之间的防晒护肤品。"
          },
          "car_washing": {
            "brief": "不适宜",
            "details": "不宜洗车，未来24小时内有雨，如果在此期间洗车，雨水和路上的泥水可能会再次弄脏您的爱车。"
          },
          "travel": {
            "brief": "适宜",
            "details": "天气较好，温度适宜，总体来说还是好天气哦，这样的天气适宜旅游，您可以尽情地享受大自然的风光。"
          },
          "flu": {
            "brief": "易发期",
            "details": "相对今天出现了较大幅度降温，较易发生感冒，体质较弱的朋友请注意适当防护。"
          },
          "sport": {
            "brief": "比较适宜",
            "details": "阴天，较适宜进行各种户内外运动。"
          }
        }
      },
      "future": [
        {
          "date": "2017-02-19",
          "day": "周日",
          "text": "阴/小雨",
          "code1": "9",
          "code2": "13",
          "high": "24",
          "low": "18",
          "cop": "",
          "wind": "微风3级"
        },
        {
          "date": "2017-02-20",
          "day": "周一",
          "text": "阴",
          "code1": "9",
          "code2": "9",
          "high": "23",
          "low": "18",
          "cop": "",
          "wind": "微风3级"
        },
        {
          "date": "2017-02-21",
          "day": "周二",
          "text": "阵雨",
          "code1": "10",
          "code2": "10",
          "high": "22",
          "low": "18",
          "cop": "",
          "wind": "微风3级"
        },
        {
          "date": "2017-02-22",
          "day": "周三",
          "text": "小雨",
          "code1": "13",
          "code2": "13",
          "high": "23",
          "low": "13",
          "cop": "",
          "wind": "微风3级"
        },
        {
          "date": "2017-02-23",
          "day": "周四",
          "text": "小雨",
          "code1": "13",
          "code2": "13",
          "high": "20",
          "low": "10",
          "cop": "",
          "wind": "北风4级"
        },
        {
          "date": "2017-02-24",
          "day": "周五",
          "text": "小雨",
          "code1": "13",
          "code2": "13",
          "high": "14",
          "low": "10",
          "cop": "",
          "wind": "北风4级"
        },
        {
          "date": "2017-02-25",
          "day": "周六",
          "text": "小雨",
          "code1": "13",
          "code2": "13",
          "high": "15",
          "low": "10",
          "cop": "",
          "wind": "微风3级"
        },
        {
          "date": "2017-02-26",
          "day": "周日",
          "text": "小雨",
          "code1": "13",
          "code2": "13",
          "high": "15",
          "low": "10",
          "cop": "",
          "wind": "北风3级"
        },
        {
          "date": "2017-02-27",
          "day": "周一",
          "text": "小雨/多云",
          "code1": "13",
          "code2": "4",
          "high": "21",
          "low": "11",
          "cop": "",
          "wind": "北风3级"
        },
        {
          "date": "2017-02-28",
          "day": "周二",
          "text": "多云",
          "code1": "4",
          "code2": "4",
          "high": "24",
          "low": "14",
          "cop": "",
          "wind": "北风3级"
        }
      ]
    }
  ]
}

解析：

status：成功时返回 OK
    weather：天气信息
    city_name：城市名
    city_id：城市 id
    last_update：上次更新时间
    now：现在天气状况
        text：天气状况
        code：???
        temperature：温度
        feels_like：体感温度
        wind_direction：风向
        wind_speed：风速
        wind_scale：风力大小
        humidity：空气湿度
        visibility：能见度，单位为 km
        pressure：气压，单位为 hPa
        air_quality：具体空气质量指数
            aqi：空气质量指数
            pm25：pm2.5指数
            pm10：pm10指数
            so2：二氧化硫指数
            no2：二氧化氮指数
            co：一氧化碳指数
            o3：臭氧指数
            last_update：上次更新时间
            quality：空气质量
    today：今日天气状况
        sunrise：日出时间
        sunset：日落时间
        suggestion：建议列表
            dressing：穿衣信息
            uv：紫外线建议
            car_washing：洗车信息
            travel：旅游信息
            flu：流感信息
            sport：运动信息
                brief：建议、说明
                details：具体信息
    future：未来天气状况列表
        date：日期
        day：周几
        text：天气状况
        code1：???
        code2：???
        high：当日最高气温
        low：当日最低气温
        cop：???
        wind：风力信息

2. 24小时天气预报
   url：http://tj.nineton.cn/Heart/index/future24h/
   拼接参数：
     city：城市
     language：语言
     key：秘钥，固定值 78928e706123c1a8f1766f062bc8676b。可不填。也可省略该参数

url 示例：http://tj.nineton.cn/Heart/index/future24h/?city=CHSH000000&language=zh-chs&key=36bdd59658111bc23ff2bf9aaf6e345c
或 http://tj.nineton.cn/Heart/index/future24h/?city=CHSH000000&language=&key=
或 http://tj.nineton.cn/Heart/index/future24h/?city=CHSH000000

json示例

{
  "status": "OK",
  "hourly": [
    {
      "text": "多云",
      "code": "4",
      "temperature": "16",
      "time": "2017-02-19T13:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "18",
      "time": "2017-02-19T14:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "17",
      "time": "2017-02-19T15:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "16",
      "time": "2017-02-19T16:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "16",
      "time": "2017-02-19T17:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "16",
      "time": "2017-02-19T18:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "15",
      "time": "2017-02-19T19:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "15",
      "time": "2017-02-19T20:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "15",
      "time": "2017-02-19T21:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "14",
      "time": "2017-02-19T22:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "14",
      "time": "2017-02-19T23:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "14",
      "time": "2017-02-20T00:00:00+08:00"
    },
    {
      "text": "多云",
      "code": "4",
      "temperature": "15",
      "time": "2017-02-20T01:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "15",
      "time": "2017-02-20T02:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "15",
      "time": "2017-02-20T03:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "15",
      "time": "2017-02-20T04:00:00+08:00"
    },
    {
      "text": "中雨",
      "code": "14",
      "temperature": "15",
      "time": "2017-02-20T05:00:00+08:00"
    },
    {
      "text": "中雨",
      "code": "14",
      "temperature": "13",
      "time": "2017-02-20T06:00:00+08:00"
    },
    {
      "text": "中雨",
      "code": "14",
      "temperature": "10",
      "time": "2017-02-20T07:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "8",
      "time": "2017-02-20T08:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "6",
      "time": "2017-02-20T09:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "5",
      "time": "2017-02-20T10:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "5",
      "time": "2017-02-20T11:00:00+08:00"
    },
    {
      "text": "小雨",
      "code": "13",
      "temperature": "6",
      "time": "2017-02-20T12:00:00+08:00"
    }
  ]
}

解析

status：成功时返回 OK
hourly：具体小时天气信息列表
    text：天气状况
    code：请参考 [code 细节]
    temperature：温度
    time：时间

另 ，code细节

/// 晴
case sunny = 0
/// 晴
case clear = 1
/// 晴
case fair1 = 2
/// 晴
case fair2 = 3

/// 多云
case cloudy = 4
/// 晴间多云
case partlyCloudy1 = 5
/// 晴间多云
case partlyCloudy2 = 6
/// 大部多云
case mostlyCloudy1 = 7
/// 大部多云
case mostlyCloudy2 = 8

/// 阴
case overcast = 9
/// 阵雨
case shower = 10
/// 雷阵雨
case thundershower = 11
/// 雷阵雨伴有冰雹
case thundershowerWithHail = 12
/// 小雨
case lightRain = 13
/// 中雨
case moderateRain = 14
/// 大雨
case heavyRain = 15
/// 暴雨
case storm = 16
/// 大暴雨
case heavyStorm = 17
/// 特大暴雨
case severeStorm = 18

/// 冻雨
case iceRain = 19
/// 雨夹雪
case sleet = 20
/// 阵雪
case snowFlurry = 21
/// 小雪
case lightSnow = 22
/// 中雪
case moderateSnow = 23
/// 大雪
case heavySnow = 24
/// 暴雪
case snowstorm = 25

/// 浮尘
case dust = 26
/// 扬沙
case sand = 27
/// 沙尘暴
case duststorm = 28
/// 强沙尘暴
case sandstorm = 29
/// 雾
case foggy = 30
/// 霾
case haze = 31
/// 风
case windy = 32
/// 大风
case blustery = 33
/// 飓风
case hurricane = 34
/// 热带风暴
case tropicalStorm = 35
/// 龙卷风
case tornado = 36

/// 冷
case cold = 37
/// 热
case hot = 38

/// 未知
case unknown = 99