Add spaces: Intheearlymorningitwillbemostlycloudy.Beforenoonwidelyovercast,butmainlydryweatherwilldominate.

Answer: In the early morning it will be mostly cloudy. Before noon widely overcast, but mainly dry weather will dominate.

Add spaces: Inadditiontoherschoolingshehadprivatemusiclessons.

Answer: In addition to her schooling she had private music lessons.

Add spaces: Thereflectorisavailableinmatt(SM),highgloss(SI)orfacetedhighgloss(SF)surface/finish.

Answer:
The reflector is available in matt (SM), high gloss (SI) or faceted high gloss (SF) surface/finish.