Using polite form for neutral subjects


I am trying to write a short message to a japanese acquaintance and am
planning to use this sentence:

> 今日はとても暑くて、雪がそろそろ溶けている。

I know that, in this context, I should use the polite form 「溶けています」. However,
for some reason, I feel like I can use the dictionary form since neither me
nor the addressee is involved in the sentence. To be more precise, if I use
「溶けています」, because of the particle が, I feel like it's the _snow_ that is being
polite.

More generally, is the polite form a "tonality" of language used
systematically in such a context, or is it a way to mark respect and
humbleness in an interaction?




The polite form (丁寧語 _teineigo_ ), also frequently referred to as です・ます調, is
used for making everyday speech more polite _across the board_.

Honorific language (尊敬語) and humble language (謙譲語), also frequently jointly
referred to as 敬語 _keigo_ , are used to elevate someone else or humble
yourself, respectively. (Honorific and humble language are usually used in the
same register, i.e. think of them as one "set".)

Usually _keigo_ is used in combination with ("on top of") _teineigo_ , but it
is possible to use one without the other.

When learning about Japanese "polite" language, _keigo_ and _teineigo_ are
often jumbled together, but it might be useful to consider them independent.

To answer your question, it would be unusual to use honorific or humble
language when talking about snow, but it is very appropriate to use polite
language, so

> 雪が溶けています

is perfectly natural (and you might want to write the whole letter in
_teineigo_ ).

* * *

As @l'électeur notes, the sentence on the whole is not 100% natural. I'm not
quite sure what exactly you want to say, but here are two possible scenarios:

> _beginning of winter_  
>  Today it is exceptionally warm and the snow is slowly melting.  
>  今日は非常に暖かくて、雪が徐々に溶けています。
>
> _end of winter_  
>  Today it is already quite warm and the snow is slowly starting to melt.  
>  今日はとても暑くて、雪が解け始めました。  
>  ＝ …、雪がそろそろ解ける季節に入りました。




The polite form (丁寧語 _teineigo_ ), also frequently referred to as です・ます調, is
used for making everyday speech more polite _across the board_.

Honorific language (尊敬語) and humble language (謙譲語), also frequently jointly
referred to as 敬語 _keigo_ , are used to elevate someone else or humble
yourself, respectively. (Honorific and humble language are usually used in the
same register, i.e. think of them as one "set".)

Usually _keigo_ is used in combination with ("on top of") _teineigo_ , but it
is possible to use one without the other.

When learning about Japanese "polite" language, _keigo_ and _teineigo_ are
often jumbled together, but it might be useful to consider them independent.

To answer your question, it would be unusual to use honorific or humble
language when talking about snow, but it is very appropriate to use polite
language, so

> 雪が溶けています

is perfectly natural (and you might want to write the whole letter in
_teineigo_ ).

* * *

As @l'électeur notes, the sentence on the whole is not 100% natural. I'm not
quite sure what exactly you want to say, but here are two possible scenarios:

> _beginning of winter_  
>  Today it is exceptionally warm and the snow is slowly melting.  
>  今日は非常に暖かくて、雪が徐々に溶けています。
>
> _end of winter_  
>  Today it is already quite warm and the snow is slowly starting to melt.  
>  今日はとても暑くて、雪が解け始めました。  
>  ＝ …、雪がそろそろ解ける季節に入りました。

