When this front approaches, the barometer falls down to 29 usually just below 30. As the barometer again begins to rise and light rain or drizzle sets in, is when these bass are triggered to feed and you need to be on the water. Other times exist such as during an extended front lasting for days. When a front immediately follows another front, or on cloudy days with little or no rain, with mild temperatures and good conditions. Early or late in the day are also good times for the bigger bass to feed on top.
Fog can extend an otherwise high pressure morning into a top water bonanza.
Even moon fazes increase your chances of getting a BIG bass bite during Winter. The best answer is whenever you can be there. Many weekend anglers are fortunate to hit a front just right and seldom do many working anglers have consecutive outings of just loading the boat. But if you can pick your days to go fishing timing is everything. So when the weatherman predicts rain a few days away and you have been fortunate enough to get a few days of sunshine, start planing a Wintertime topwater fishing trip.