As we roll into the month of May, we’re seeing the telltale signs that our runoff season has officially arrived. With recent and forecasted warm temperatures across the state, we will continue to see the melt-off of our winter snowpack as well as increased river flows as we progress through the first half of May. As you can see from the snow water equivalent graph below, our winter snowpack peaked on April 7, followed by a bump in snowfall the following week, but has since continued its downward trend.

With forecasted temperatures in the low 50’s for most mountain valleys, the first stage of our seasonal runoff will entail melting of the mountain snowpack up to around 11,000 ft of elevation, which will provide a noticeable increase in river flows across the state. I consider this the first stage of our annual runoff cycle, as the snowpack at higher elevations will largely remain in place due to lower temperatures.

Once we begin to see higher temperatures in the mountain valleys, this will translate to higher temperatures at increased elevations and the beginning of the melt-off of the high-elevation snow. When this begins we’ll enter into the second phase of our runoff season, which will help keep rivers at higher flows and aid in scouring unwanted sediment accumulated during the past couple of years of drought and low flows. From a fishing perspective, the question is whether the first and second phases will fall back to back, or if we will see a period of dropping flows while we wait on the melting of high-elevation snow. At this time this scenario is unknown, but I will certainly keep our readers up-to-date on the changes that we see coming.

From a snowpack perspective, the state of Colorado is still trending well above average for this time of year, as is noted in the snowpack map below.

With the exception of the Arkansas and South Platte River basins, the rest of the state is trending well above average, which is a tremendous sigh of relief for the entire Rocky Mountain West. Following multiple years of below-average snowfall, this winter has proven a boon to our seasonal water needs, as the entire Colorado River system is currently sitting flush with snowpack and future forecasted water. And while we are in a positive position for the time being, it is imperative that we all remember that every winter brings different levels of participation, as do our summer months, and while we are currently in a comfortable position, things can always change moving forward.

As we move into our summer months, weather cycles are anticipating a generally wet summer, with traditional monsoonal weather patterns predicted to hit Colorado. This is both a blessing and a curse, as any significant rainfall early in the season will expedite the runoff cycle, but later season moisture will help keep rivers and reservoirs full. As noted this is ultimately up to Mother Nature to decide how things progress, so the best thing we can all do is be thankful for the water we can anticipate coming into our rivers while being cautionary about what the future will hold.

To close out this Snowpack Update, I wanted to touch on what we can all expect as it relates to getting out on the water. As expected freestone rivers are currently running high and off-color, which makes fishing these rivers on lower sections a dicey proposition due to the numerous tributaries that flow in. The upper river sections will provide better conditions, as flows will be more tempered with fewer tributary rivers coming in. So for the Colorado, Eagle, Roaring Fork, Gunnison, and other notable freestone fisheries, plan your days on the upper stretches and keep heading up river until you can find cleaner water. From a float fishing perspective, all I can say is be cautious where you choose to float, always be watchful of the daily hydrographs to see what flows are doing, and be mindful to float within your ability level. Many rapids that are Class II or III during lower flows will only become more technical and dangerous, so if you haven’t floated a section of river at higher flows, do your due diligence and research beforehand to ensure you are capable of navigating the conditions you will encounter.

Tailwaters on the other hand will be much more predictable in terms of river flows, as the controlled releases will offer more consistent clean water, and likely manageable flows from a wading perspective. As reservoirs begin to fill, we will see flows on these rivers start to increase, but in my experience this will only lead to better fishing as any increase in river flows will only increase the available bug life, creating more aggressive feeling patterns from the resident fish. Be sure to think BIG when it comes to your rig, as increased flows will translate to larger bugs, and less wary fish, which means larger flies, and leader and tippet will be your best bet for success.

As always our knowledgeable staff and guides are always here to help you make the most of your day on the water, so never hesitate in reaching out for a guided trip, river report, and gear recommendations for your next day on the water.

Signed,

Tucker Ladd
Owner & President - Trouts Fly Fishing