Does it seem like we have had a wet fall? It has been. It has also been similar to last fall. In the chart below, I have plotted the daily and cumulative precipitation for the months of September through November for the last 4 years.
The daily precipitation is in the bar chart at the bottom, and uses the right axis. The cumulative precipitation is in the line chart and uses the left axis. The falls of 2008 and 2009 were considerably drier. Both the falls of 2010 and 2011 have seen the onset of La Nina. This could be a reason. Fall of 2008 brought the emergent warming of the equatorial Pacific Ocean with El Nino setting in during 2009. Since late 2009, the equatorial Pacific Ocean has cooled with back to back La Nina events.
I also took a look at temperatures for the last four falls. Other than this fall appearing cooler than the last 3, I struggled to find a meaning sign of a trend. With that said, this month to date is more than 4 degrees below normal. October was 0.7 above normal and September was 1.4 above normal.
The chances of added precipitation for the rest of the month keep popping in and out of the forecast models. The GFS and NoGAPs models are not consistent with each other. GFS this morning is showing a snowy Thanksgiving.