What time of day does [後]{のち} cover in 天気予報?


Often the weather forecasts will say something like

> 晴れ **[後]{のち}** 所により曇り → Sunny/Clear; later Partly Cloudy

In English, most weather reports use more precise with time ranges, like
`(early/mid/late) morning`, `noon`, `(early/mid/late) afternoon`, `(early)
evening`, `night time`, `late night`, and I think most people have a good
approximation of when these ranges cover (some likely overlap).

>   * Morning: 5:00-12:00
>     * Early: 5:00-7:00
>     * Mid: 7:00-10:00
>     * Late: 10:00-12:00
>   * Noon: 11:30-13:00
>   * Afternoon: 12:00-17:00
>     * Early: 12:00-14:00
>     * Mid: 14:00-15:30
>     * Late: 15:00-17:00
>   * Evening: 17:00-20:00
>     * Early: 17:00-18:30
>   * Night Time: 20:00-24:00
>     * Late Night: 22:00以降
>

But the "later" that [後]{のち} uses seems very vague. When I hear it, I usually
think "afternoon on(ward)". Is there an exact range it covers, or even an
approximation that most people understand? Or is it basically when the new
conditions start?




According to Japan Meteorological Agency, by definition, "AのちB" stands for "A
for the first half (of the period being forecasted), then B for the latter
half."

<http://www.jma.go.jp/jma/kishou/know/faq/faq10.html>

Obviously the actual time depends on the "forecast period". Unless otherwise
specified, "weather reports for tomorrow" on evening TV shows refer to the
weather from 0:00 to 24:00 on the following day. So in this case, "AのちB" means
"A in the morning (until noon), then B until midnight".

However, "weather reports for today", announced 5:00AM daily by JMA for
example, covers the resting 19 hours of that day. Theoretically, in this case,
the border between A and B will be around, 14:30.

That said, I think most Japanese people do not care for such details. After
all, there are always errors in weather forecasting, and when precision is
needed, they just avoid using "のち".




According to Japan Meteorological Agency, by definition, "AのちB" stands for "A
for the first half (of the period being forecasted), then B for the latter
half."

<http://www.jma.go.jp/jma/kishou/know/faq/faq10.html>

Obviously the actual time depends on the "forecast period". Unless otherwise
specified, "weather reports for tomorrow" on evening TV shows refer to the
weather from 0:00 to 24:00 on the following day. So in this case, "AのちB" means
"A in the morning (until noon), then B until midnight".

However, "weather reports for today", announced 5:00AM daily by JMA for
example, covers the resting 19 hours of that day. Theoretically, in this case,
the border between A and B will be around, 14:30.

That said, I think most Japanese people do not care for such details. After
all, there are always errors in weather forecasting, and when precision is
needed, they just avoid using "のち".

