Very likely it is moisture in the fuel injection points. This car has 2 sets of points, one for ignition in rotor cap, and another set in lower stem of distributor. An annoyance more than a problem. Common problem on all those early electronic fuel injection sets.
You can remove the distributor and clean/dry the points, but I have not tried it. Seen it done. Depends on how familiar you are with working in this area.
Gary