unexpected
extraordinary
improbable
more than expected
out-of-the-way
past expectation
sudden
unanticipated
undivined
unforeseeable
unforeseen
unguessed
unheralded
unhoped for
unpredictable
unpredicted
unprepared for
without warning
infrequent
inopportune
late-night
on-site
periodic
preflight
presume
two-week
unasked
unauthorized
unceremonious
undesired
unexplained
uninvited
unlooked-for
unplanned
unscheduled
unsought
unwanted
unwelcomed
unwilled
weeklong
announced
bounced
denounced
mispronounced
pounced
pronounced
renounced
trounced