An under-the-radar stock market indicator is pointing to more gains ahead

• An under-the-radar stock market indicator just flashed, suggesting more upside ahead.
• The December Low indicator occurs when the S&P 500 stays above its December low throughout the first quarter.
•  "It would be quite abnormal to expect a massive bear market and a horrible year for stocks this year," Carson Group's Ryan Detrick said.

The stock market just flashed an under-the-radar signal that suggests more upside ahead, according to the Carson Group's chief market strategist Ryan Detrick.

The December Low indicator, according to Detrick, occurs when the S&P 500 stays above its prior December low throughout all of the first quarter.