The weather on Lake Nipissing can surprise first-time visitors with its range of temperatures and rapid changes from sun to rain and back again. During our latest vacation in mid-July the daytime temperatures ranged from 73 to 93 degrees and the evening temperatures dipped down to 50 degrees! I suspect that the variability of the weather can be attributed in part to the northern locale of the lake. The weather patterns appear to be more pronounced and rapidly shifting than those that I am accustomed to in Pennsylvania. The most significant aspect of this changing weather is the wind that it produces on most days. This wind can vary in direction and intensity on an almost hourly basis. The wind in many cases will dictate where you fish and how you fish for angling success. A moderate breeze can easily produce 2 and 4 foot swells on the main lake that will send most anglers looking for calmer waters. Fortunately, a good portion of the southen arm of Lake Nipissing is sheltered by many small islands and rocky outcrops which allow anglers to fish even on the windiest days. One consequence of this is that you generally will not be fishing the deeper waters (15 + feet deep) in the main lake.
There are several aspects of the weather that will affect your fishing success. The following are observations that I have made over the years when fishing Lake Nipissing.
1. On windy days, the bigger gamefish will move towards the shoreline that the wind is blowing towards. They tend to station themselves along weedlines or reeds near the shore. Generally, they are not in the weeds but up to 100 feet out away from the weeds or reeds. This pattern works best when the wind has been blowing from the same direction for 6 to 12 hours.
2. Fishing is best right before a storm front arrives or during a light steady rain. It is definitely worth getting wet to catch bigger fish and greater numbers of fish.
3. The day after a cold front passes will have the slowest fishing. The sky will be clear and bright blue. The air will be dry and cooler. It will be breezy. Great weather for the fishermen, but NOT great weather for catching fish. This is a good day to go sight-seeing with the family.