Winter weather has shifted to warm air temperatures, but the melting of snow and ice are keeping water temps down. Spillover from Prettyboy, which has ice on its surface, has water temps as much as 6-8 degrees below the normal low-mid 40’s of February. A rough mix of half bottom release, and half icy spillover from Prettyboy has reversed the normal “warmer release closer to the dam” theory. Here are a few things we thought we would share about some differences this year in regards to water temps from previous years.
The Gunpowder has hovered around 37-40 degrees F midday for the past few weeks, and the recent warm days did have an effect on water temps and hatches, just not in the upper miles of river. On Wednesday in 62 degree weather the water below the dam was 40.5 degrees at 2 pm, and just a few hatching midges. At 3 pm four miles down river the temps hit 45 degrees, which was two degrees warmer than the previous day, at the same place and time. Four miles of exposure to the sun meant a difference of 4.5 degrees and accounted for a lot of midges and a few sized 16 stoneflies. The fish were holding tight and not willing to strike my skating stonefly pattern, so it wasn’t quite warm enough.
Last year I recorded similar water/air temps and the first stonefly appearance around January 29th in the Falls Rd area. Falls Road has the coldest water temps this year, so consider dipping a thermometer, and checking a few areas before suiting up. Numerous anglers reported seeing a few stones flying around or crawling on the bank in air temps in the upper 40’s. Nymph fishing, while tough has yielded at least a bite or two. A few anglers have reported catching half a dozen on recent outings with dark nymph patterns.