Code to check if Workbook Exists

[Jo15765]

I have (in Excel) code similar to this:

Public Sub One()
Dim varStar
Dim varStars

varStar = Array("Rain", "Sleet", "Snow")

For each varStar in varStars

Call Precipitation (varStar)
Call Monthly (varStar)
Call Weekly (varStar)
Call Yearly (varStar)

Next varStar
End Sub

Public Sub Monthly (varStar)
        On Error Resume Next
        Set WB = Workbooks.Open(Filename:="" & varStar)
        Run "RefreshOnOpen"
        With WB
            WB.SaveAs Filename:="" 
        End With
        WB.Close
        On Error GoTo 0
End Sub

And then from there it will call the corresponding module and pass varStar to each module and run the code. The issue I have is that sometimes (like right now) it is a new year, or a new month and varStar may not exist in the specific workbook. How can I code it to, if varStar doesn't exist just skip it and keep going. I tried On Error Resume Next, and On Error GoTo 0. But that wasn't 100% efficient. If you need to see additional coding, let me know, and I can provide more.