不期而至

bùqīérzhì
  1. to arrive unexpectably
  2. unexpected

CEDICT

Entry Composition

1 不期 bùqī
  1. unexpectedly
  2. to one's surprise
2 而 ér
  1. and
  2. as well as
  3. and so
  4. but (not)
  5. yet (not)
  6. (indicates causal relation)
  7. (indicates change of state)
  8. (indicates contrast)
3 至 zhì
  1. to arrive
  2. most
  3. to
  4. until

Related entries

不测 bùcè
  1. unexpected
  2. measureless
  3. unexpected circumstance
  4. contingency
  5. mishap
不虞 bùyú
  1. unexpected
  2. eventuality
  3. contingency
  4. not worry about
出乎意料 chūhūyìliào (idiom) unexpected
这出乎意料地容易。

It was amazingly easy.

Source: Tatoeba

出人意料 chūrényìliào
  1. unexpected (idiom)
  2. surprising
想不到 xiǎngbudào
  1. unexpected
  2. hard to imagine
  3. it had not occurred to me
  4. who could have thought that
我想不到好的用户名

I can't think of a good username.

Source: Tatoeba

意外 yìwài
  1. unexpected
  2. accident
  3. mishap

classifier: 個

意外发生在两年前。

The accident happened two years ago.

Source: Tatoeba

意想不到 yìxiǎngbùdào
  1. unexpected
  2. previously unimagined
一時失言常常會帶來意想不到的結果。

A slip of the tongue often brings about unexpected results.

Source: Tatoeba

惊爆 jīngbào
  1. unexpected
  2. staggering (news etc)
不速 bùsù
  1. uninvited (guest)
  2. unexpected (appearance)
  3. unwanted presence
横 hèng
  1. harsh and unreasonable
  2. unexpected
你从这里过去到那里，穿过第二条横马路就是。

You can get there by crossing the street at the second intersection.

Source: Tatoeba

骤 zhòu
  1. sudden
  2. unexpected
  3. abrupt
  4. suddenly
  5. Taiwan pr. zòu
天空风云骤起。

The sky looks angry.

Source: Tatoeba

未料 wèiliào
  1. to not anticipate
  2. to not expect
  3. unanticipated
  4. unexpected