Powershell error when creating a new SharePoint Site

I ran into another odd problem with my SharePoint 2010 deployment yesterday.  I was trying to create a new site using the New-SPWeb PowerShell command and I kept getting the following error message:

PS C:\Users\rsmw> new-spweb http://sharepoint.local/newspweb
New-SPWeb : Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))
At line:1 char:10 + new-spweb <<<<  http://sp2010.mps.k12.mi.us/warrensm2
 + CategoryInfo          : InvalidData:
(Microsoft.Share....SPCmdletNewWeb:SPCmdletNewWeb) [New-SPWeb],
UnauthorizedAccessException
 + FullyQualifiedErrorId : Microsoft.SharePoint.PowerShell.SPCmdletNewWeb

The account I was logged in with was a farm administrator and I could create sites through the web interface.   Apparently, I needed to add the farm administrator account to the Owners group of the parent site in order to create a new site. After that, all was good to go.