Chances of catching a Grunion run in San Felipe are in the full or new moon periods between February and April.
Showing up the next 3 days following the full moon or new moon cycles would be within the typical grunion pattern. My experience is that the best run is on the first of these days during the full moon period. Winds may also come into play because of their effect in pushing the water further up the beach and delaying or postponing the days run. In this regard, March and April are better (less windy) than February.
The best leads come from retired Americans who may be sitting at home and happen to notice the run when they get up to change the channel or to refresh their Margarita. In short, the whole observation system is pretty haphazard.
From the photographer’s point-of-view, however, the big problem is that the grunion run just may not happen on that lunar cycle – or it may happen many miles away from where we can observe it.
Grunion runs can be spectacular and may stretch for several miles along the beach. Generally the best shows occur on the beaches south of town from the harbor towards Punta Estrella.
You should look at our tide calendars for February, March and April and pick days that are 2-3 days after the full or new moon. Days during the middle of the week are better (fewer people).
Check for the grunion run on the afternoon tides, 2-3 hours after the high tide, i.e around 4-5 pm.