Is Salem, Oregon Warming?

There have been some discussions, but not much data, over at Roy Spencer's site about the trend in Pacific Northwest temperatures, and in particular the trend in Salem, Oregon's temperatures.

Chuck Wiese linked to a chart he said was compiled by Mark Albright, showing Salem's annual mean daily maximum temperature, 1932-2013. But he couldn't provide the underlying data, or explain why the chart ends in 2013.

The National Weather Service gives monthly temperatures for Salem from 1892-present -- Tmax, Tmin, Precipitation and Snow. Some data are missing, with an "M" for that month. I only took an annual average only if there were no missing months. Here's what I get for Tmax (all temperatures in Fahrenheit):

I don't know where Albright or Wiese got their data, but the data I obtained shows a trend in Tmax of +0.15°F/decade.

Wiese explained why Albright began his plot in 1938:

Mark Albright chose 1938 as a starting point because before this time, Salem, OR was not a first order station. The conversion took place in 1937 and before this time, there were months of records missing from the station.

Starting at 1938, my data show a linear trend of +0.09°F/decade.

By the way, the trend of Tmax since 1970 is +0.31°F/decade.

I do find the trend from 1938-2013 to be zero. These last four years were very warm here, and make a significant difference.

So the fraud trick to Chuck Wiese's claim is: don't include all the data. Especially when they're warm.

PS: To be clear, I'm not faulting Mark Albright. He made a graph and it stands on its own. I'm calling out Chuck Wiese for trying to push data that aren't up-to-date.