我觉得应该是API这边做了限制，请看OpenWeatherMap API官网上写的：

How to work with us effectively

These are several recommendations how to work with our free service in more effective way:

• Do not send requests more then 1 time per 10 minutes from one device.The weather is changing not so frequently as usual.
• Use the name of the server as api.openweathermap.org. Please never use the IP of the server.
• If possible please use city ID or city name instead of city coordinates. It is let us use cash server more effective.
• The service is absolutely free and has some limitation of capacity. So if you do not get respond from server please do not try to repeat your request immediately, please repeat it in 10 min. Also please store your previous request data.
• If you need secured SLA please contact us.

以及价目表上的情况，明确表明API有频率限制了。而且是申请了API的情况下。像你这样直接就抓接口的人肯定有很多，也就是共用一个接口的人很多，所以更甚。所以正确的做法是去老老实实的申请一个Key啦，然后按照倒数第二条写的一样，按照规定频率去做查询然后存储数据，自己网站这边访问只需要读取存储好的数据就好啦。