Job growth & the unemployment rate, yield curve spread, index of leading indicators, home price appreciation, and the "Buffet Ratio" are all data I like to look at when analyzing where we are in the economic cycle.  

US Unemployment Rate (green); Yield Curve Spread + 5% (blue)

The US unemployment rate (above) rarely stays below 5% for long before there is a recession. A low yield curve spread (10-yr - 2yr) going negative​ is another indicator a recession is on its way. 

US Employment Growth (green); US Leading Index (blue)

Year-over-year employment growth is another way to look at the jobs picture, and the Leading Index of Economic Indicators typically precedes the movement of employment growth or declines, as a clue to where we are going. US employment growth (above) has decelerated to below 2%. And in late 2018 and early 2019, the Leading Index stumbled to just over 1%, a key historic threshold that significantly increases the risk of a recession. 

California Employment Growth; CA Leading Index

California employment growth and the California Leading Index look similar to the country as a whole, except that peaks and troughs tend to be more pronounced. CA employment growth peaked at 3.26% in July 2015, before decelerating to below 2% from July 2018 through early 2019. However, unlike the Nationwide data, California's Leading Index already fell and remained below the critical 1% level in the first 4 months of 2019. If the Leading Index remains below 1% and employment growth follows, there is a significant increase in the risk of a recession, based on historical levels for the last 3 economic cycles. 

Warren Buffet believes that the value of the stock market as a % of GDP as a whole is a good measure of value of where the stock market should be during the economic cycle. The higher the stock market is valued relative to the economy (GDP), the less likely we are to have high stock market returns going forward from today. And vise versa.