Final answer:
The most likely weather to develop with a small and decreasing temperature-dewpoint spread and a temperature of 62°F is increased cloudiness or fog, not specifically freezing precipitation or thunderstorms.
Step-by-step explanation:
If the temperature/dewpoint spread is small and decreasing, and the temperature is 62°F, weather conditions that are most likely to develop would be those associated with increased moisture and potential precipitation, such as fog or overcast skies.
These conditions are conducive to cloud formation and precipitation, though not specifically freezing precipitation or thunderstorms unless other atmospheric conditions are present. The phenomena discussed in the reference materials confirm that as the temperature nears the dew point, the condensation of water vapor typically occurs, which releases latent heat and tends to stabilize the air temperature, preventing it from falling further.