This is a gentle snow. Temperatures are cold and getting colder, so this is not the sort of snow that threatens to bend and break branches. It accumulates on branches of evergreens, trapped by dense needles, but even the tall stems of nandinas (Nandina domestica, below) do not arch under the slight weight. Reports are that it is no picnic to be driving about in, but it is not a bother to the garden.
With nights forecast to fall to a bit below ten degrees there is little concern over the fate of evergreens, or the few marginally cold hardy shrubs that survived last winter’s lows. Certainly these will have no problems as along as temperatures remain above zero.
There is some small concern over the gardenias (Gardenia jasminoides). These are the supposedly cold hardy ones that all died last winter, but were planted again in an act of faith that temperatures will not again venture much below zero.
The flowers of mahonias (Mahonia x media ‘Charity, above) and Vernal witch hazel (Hamamelis vernalis, below) will have no problem with this cold. When overnight temperatures dropped below zero last winter these remained in bloom, so a few nights of cold will not bother them at all.
Ramblin' through Dave's Garden 
The flowers in the snow are very beautiful. Fingers crossed that your Gardenia plants survive. Even here in the mountains west of Sydney, I can’t get Gardenias to grow (I am the equivalent of USDA zone 8) as they yellow and drop their leaves after any prolonged cold, so it will be interesting to see how yours fare
The gardenias are called zone 6a and 6b cold hardy, but it’s fair to question these designations when they died at five and six degrees below zero (Fahrenheit). Fortunately, many shrubs proved to be sturdier than their zone ratings, so if gardenias are the only shrubs that I cannot keep, it’s not so bad.
Seeing your mahonia in the snow makes me think I should give it a try. We dipped slightly below zero last winter so probably aren’t that much different than your lows. I’m going to hold off on the gardenias for a bit though.
Mahonias are rated for zone 7, a low of zero, but they survived 6 below with only some burn to foliage. I wouldn’t want to subject them to an entire winter below zero, but a handful of days were not a problem. Flowers from November into January are good reason to give these mahonias a try.