Confused about the structure of this sentence


I have difficulty deciphering the meaning and structure of the bold sentence
below

> 遠くから、近くから、無数に折り重なる波音を風が運んできた。
> **曇天に白点ひとつ、さみしく鳴く春かもめが、雪の名残ひとひら、まだ冷たい三月の風だった。**

This sentence contains lots of commas so it looks like there are multiple
smaller sentences combined into one. I'm uncertain about the が after 春かもめ. It
marks subject for what?

Also, I don't understand the meaning of 白点 here.




It is almost like a prose poem at best, and not really parsable as a sentence.

白点 should be simply _a white dot_ referring to the seagull or snowflake (or
both even if inconsistent with ひとつ).

One possible interpretation:

> 曇天に白点ひとつ、さみしく鳴く春かもめが、

Here かもめ is the subject for some missing verb modified by 曇天に白点ひとつ: _A spring
seagull crying sadly (flies like) a white dot in the cloudy sky_.

> 雪の名残ひとひら、まだ冷たい三月の風だった。

Here both are noun phrases describing the situation: _A snowflake (in the
air), (there was) March wind which was still cold._

* * *

Another possibility is to consider literally かもめが as subject for 三月の風だった: _A
spring seagull crying sadly, (which looks like) white dot in the cloudy sky,
with a snowflake, was the cold March wind._

Anyway it is a description of a scenery with seagull and snow in the cold
wind.




It is almost like a prose poem at best, and not really parsable as a sentence.

白点 should be simply _a white dot_ referring to the seagull or snowflake (or
both even if inconsistent with ひとつ).

One possible interpretation:

> 曇天に白点ひとつ、さみしく鳴く春かもめが、

Here かもめ is the subject for some missing verb modified by 曇天に白点ひとつ: _A spring
seagull crying sadly (flies like) a white dot in the cloudy sky_.

> 雪の名残ひとひら、まだ冷たい三月の風だった。

Here both are noun phrases describing the situation: _A snowflake (in the
air), (there was) March wind which was still cold._

* * *

Another possibility is to consider literally かもめが as subject for 三月の風だった: _A
spring seagull crying sadly, (which looks like) white dot in the cloudy sky,
with a snowflake, was the cold March wind._

Anyway it is a description of a scenery with seagull and snow in the cold
wind.

