〜おそれがある
There is a risk that 〜おそれがある
Meaning
"There is a risk / danger that ~".
Formation
[verb dictionary] + おそれがある · [noun] の + おそれがある （written 恐れがある）
Notes
Only bad possibilities, and only in forecasts, news and official warnings. It is not used about oneself: for everyday guesses the plain かもしれない is what you want.
Examples
台風（たいふう）が上陸（じょうりく）するおそれがあります。
There is a risk that the typhoon will make landfall.
Breakdown
この薬（くすり）は副作用（ふくさよう）のおそれがあります。
This medicine carries a risk of side effects.
Breakdown
大雨（おおあめ）で川（かわ）が増水（ぞうすい）するおそれがあります。
The heavy rain may cause the river to rise.
Breakdown
放置（ほうち）すると火事（かじ）になるおそれがあります。
Left unattended, it risks starting a fire.
Breakdown
個人情報（こじんじょうほう）が流出（りゅうしゅつ）するおそれがあると発表（はっぴょう）されました。
It was announced that personal data may have leaked.
Breakdown
⚠️ Often confused with
〜そうだ (伝聞)
I heard that 〜そうだ (hearsay)
Hearsay — "I heard that ~ / they say that ~". Reports information obtained from another so...
〜そうだ (様態) / 〜そうに / 〜そうな
Looks like 〜そうだ (conjecture)
Visual conjecture based on appearance — "looks like ~ / seems about to ~". Based on what y...
〜らしい
Apparently / seems 〜らしい
Conjecture based on some evidence or hearsay — "apparently ~ / I hear that ~ / it seems ~"...
〜みたいだ / 〜みたいな / 〜みたいに
Looks like / seems 〜みたいだ
Conjecture based on appearance or impression — "it looks like ~ / it seems ~". More casual...
〜ようだ / 〜ような / 〜ように
Appears / seems 〜ようだ
Conjecture or resemblance — "it appears that ~ / it seems ~ / like ~". More formal than み...
〜かもしれない
Might / perhaps 〜かもしれない
Expresses possibility — "might / perhaps / may". Indicates something is possible but not c...
〜はずだ / 〜はずです
Should be 〜はずだ (expectation)
A strong expectation based on logic or evidence — "should be ~ / ought to ~ / is supposed...
〜はずがない / 〜はずありません
Cannot be / no way 〜はずがない
Strong denial of possibility — "there's no way ~ / it cannot be that ~ / impossible". The...
〜に違いない
Must be 〜に違いない
A confident inference — "must be ~", "I am sure ~".
〜かねない
Might well 〜かねない
"Might well ~", "could easily end up ~" — of a feared outcome.