Update: Maybe not just the west coast. I added Montana etc at bottom

Using TMAX data from the new BEST release (here is Oregon)  I calculated 5 year averages for every country/state. TMAX fell off a cliff …

Top 10 TMAX 5 year averages

The current 5 year period is ranked No. 6 for contiguous-united-states

1 2001 – 2006 0.64
2 1996 – 2001 0.61
3 1951 – 1956 0.56
4 1986 – 1991 0.5
5 1931 – 1936 0.46
6 2006 – 2011 0.33
7 1936 – 1941 0.24
8 1941 – 1946 0.12
9 1906 – 1911 0.04
10 1926 – 1931 0.02

No. 15 for washington

1 2001 – 2006 0.9
2 1936 – 1941 0.83
3 1986 – 1991 0.56
4 1921 – 1926 0.51
5 1991 – 1996 0.44
6 1996 – 2001 0.42
7 1931 – 1936 0.32
8 1956 – 1961 0.31
9 1966 – 1971 0.2
10 1941 – 1946 0.2
11 1976 – 1981 0.05
12 1901 – 1906 0.04
13 1961 – 1966 0.03
14 1926 – 1931 -0.02
 15 2006 – 2011 -0.04

No. 12 for oregon

1 2001 – 2006 0.68
2 1986 – 1991 0.56
3 1936 – 1941 0.51
4 1991 – 1996 0.45
5 1931 – 1936 0.4
6 1996 – 2001 0.39
7 1956 – 1961 0.33
8 1921 – 1926 0.23
9 1976 – 1981 0.09
10 1966 – 1971 0.09
11 1961 – 1966 -0.04
12 2006 – 2011 -0.05

Alaska – tied for 3rd. .83C colder than previous 5 year period.

1 2001 – 2006 1.79
2 1976 – 1981 1.25
3 2006 – 2011 0.96
4 1936 – 1941 0.96

California – tied for 8th

1 1956 – 1961 0.54
2 1991 – 1996 0.48
3 1986 – 1991 0.48
4 1931 – 1936 0.47
5 2001 – 2006 0.45
6 1976 – 1981 0.35
7 1926 – 1931 0.28
8 2006 – 2011 0.21
9 1996 – 2001 0.21

Idaho – tied for 11th

1 1986 – 1991 0.72
2 1936 – 1941 0.61
3 1996 – 2001 0.6
4 2001 – 2006 0.57
5 1931 – 1936 0.57
6 1956 – 1961 0.33
7 1991 – 1996 0.31
8 1976 – 1981 0.26
9 1921 – 1926 0.1
10 1951 – 1956 0.03
11 2006 – 2011 0.01
12 1961 – 1966 0.01

Nevada – 15th
1 1956 – 1961 0.52
2 1931 – 1936 0.45
3 1976 – 1981 0.34
4 1991 – 1996 0.3
5 1986 – 1991 0.29
6 2001 – 2006 0.27
7 1996 – 2001 0.25
8 1926 – 1931 0.15
9 1936 – 1941 0.05
10 1946 – 1951 0.02
11 1886 – 1891 0
12 1951 – 1956 -0.01
13 1921 – 1926 -0.04
14 1901 – 1906 -0.04
15 2006 – 2011 -0.06

No. 15 for utah

1 1931 – 1936 0.5
2 1996 – 2001 0.45
3 2001 – 2006 0.37
4 1956 – 1961 0.37
5 1976 – 1981 0.35
6 1951 – 1956 0.28
7 1991 – 1996 0.26
8 1986 – 1991 0.17
9 1936 – 1941 0.1
10 1896 – 1901 0.02
11 1961 – 1966 -0.04
12 1946 – 1951 -0.04
13 1941 – 1946 -0.05
14 1906 – 1911 -0.09
15 2006 – 2011 -0.1

Montana – #9

1 1986 – 1991 1.25
2 1996 – 2001 1.03
3 2001 – 2006 0.92
4 1931 – 1936 0.72
5 1936 – 1941 0.65
6 1956 – 1961 0.38
7 1976 – 1981 0.29
8 1941 – 1946 0.25
9 2006 – 2011 0.2

Wyoming – #12

1 1931 – 1936 0.7
2 2001 – 2006 0.69
3 1996 – 2001 0.67
4 1986 – 1991 0.59
5 1951 – 1956 0.55
6 1936 – 1941 0.4
7 1976 – 1981 0.35
8 1956 – 1961 0.14
9 1961 – 1966 0.11
10 1906 – 1911 0.07
11 1991 – 1996 0.02
12 2006 – 2011 0.01

Arizona – #3 (ok … not a cliff)

1 2001 – 2006 0.61
2 1996 – 2001 0.52
3 2006 – 2011 0.41

Colorado – #7

1 2001 – 2006 0.8
2 1931 – 1936 0.66
3 1951 – 1956 0.62
4 1996 – 2001 0.57
5 1976 – 1981 0.34
6 1961 – 1966 0.16
7 2006 – 2011 0.15

New Mexico tied for #3 (not a cliff)
1 2001 – 2006 0.67
2 1951 – 1956 0.63
3 2006 – 2011 0.57
4 1996 – 2001 0.57

North Dakota – #12 1.61C colder than the warmest period!

1 1986 – 1991 1.73
2 2001 – 2006 1.13
3 1996 – 2001 0.98
4 1931 – 1936 0.53
5 1936 – 1941 0.52
6 1956 – 1961 0.5
7 1976 – 1981 0.35
8 1951 – 1956 0.3
9 1926 – 1931 0.21
10 1941 – 1946 0.19
11 1971 – 1976 0.17
12 2006 – 2011 0.15