。
The train will probably reach the station by noon.
Literal
Train [topic-は] noon [until-までに] station [at-に] arrive [probably-だろう].
までに ('by [time]') is the deadline particle, distinct from まで ('until, continuing through'). までに means 'no later than,' while まで means 'continuously through.' ~だろう is the plain-form conjectural ending ('probably, I'd guess'), attached directly to the verb's dictionary form.