Someone on a LiveJournal community pointed this out to me this morning. Early this morning, there was an interesting-looking warm-core system west of California, that appeared to have subtropical characteristics:

However, when I went to check it a few hours later, it had been sheared apart, but the extratropical system it's being absorbed into is absolutely massive:

Loop: http://www.ssd.noaa.gov/goes/west/nepac/loop-avn.html