如何拿到[]interface{}里面有的map

package main

import (
    "net/http"
    "io/ioutil"
    "encoding/json"
    "fmt"
)

func main() {
    addr := "http://wthrcdn.etouch.cn/weather_mini?city=上海"
    resp, err := http.Get(addr)
    defer resp.Body.Close()
    if err != nil {
        panic(err)
    }
    b, err := ioutil.ReadAll(resp.Body)
    var v map[string]interface{}
    json.Unmarshal(b, &v)
    v1 := (v["data"]).(map[string]interface{})
    v2 := v1["forecast"]
    fmt.Println(v2)
}

===================到最后是一个[]interface{}=======================

[map[type:晴 date:19日星期四 high:高温 27℃ fengli:<![CDATA[<3级]]> low:低温 16℃ fengxiang:东南风] map[date:20日星期五 high:高温 27℃ fengli:<![CDATA[3-4级]]> low:低温 17℃ fengxiang:东南风 type:晴] map[type:多云 date:21日星期六 high:高温 27℃ fengli:<![CDATA[3-4级]]> low:低温 19℃ fengxiang:东南风] map[date:22日星期天 high:高温 25℃ fengli:<![CDATA[<3级]]> low:低温 15℃ fengxiang:东南风 type:小雨] map[date:23日星期一 high:高温 21℃ fengli:<![CDATA[3-4级]]> low:低温 13℃ fengxiang:西北风 type:中雨]]

========================================================== 想不到怎么处理了， 求解