Madison River
Upper

Flows/Temperatures (as of September 17th; click the name for real-time numbers)
Hebgen Outflow - 759.9 CFS

Kirby - 864 CFS
Kirby High/Low Temps - 62/53F

Cameron - 926 CFS
Cameron High/Low Temps - 60/54 F

This Week's Weather Forecast in the Valley

Upper Madison
Fall is settling into the valley in truth now. We've got some rain rolling through this weekend, and with temps below freezing most nights, the Madison is falling into its usual late-season patterns. Fishing is a bit slow to start up in the mornings, with the bite turning on around 10-11 am in my experience, and getting better as the air warms up.
The dry fly bite has slowed but is by no means done, with the periodic BWO hatches and caddis bringing eager rises in the slicks and along the banks. Hoppers can still bring a fish up as well, but from my experience, fish are much more tentative to rise on foam than they have been in weeks past. Nymphing is the most productive method (as usual, I know), with smaller mayfly emergers and general attractors being the ticket if fishing is slower. As this rain continues, streamers/swung flies will gain traction and attract those fish eager to eat before the true cold arrives!

Dry Flies - Winna Spinna, Ant Acid, Arricks Flying Ant, Parachute Adams
Nymphs - Olive Hot Spot, Sunburst Perdigon, BBQ Baetis, Red Neck

Flows/Temperatures (as of September 10th; click the name for real-time numbers)
Hebgen Outflow - 759.9 CFS

Kirby - 864 CFS
Kirby High/Low Temps - 62/52F

Cameron - 938 CFS
Cameron High/Low Temps - 61/53 F

This Week's Weather Forecast in the Valley

Upper Madison
Although the colder weather did widen out the time slots fish are eating in, fishing is still a little tricky. A dry dropper setup has been doing well, especially in the afternoons after the air warms up a little bit and fish start looking for a bite to eat. I've found that red/brown ants with enough foam to hold up the dropper are working the best, but beetles with a bit of flash also have done the trick. On the dropper side of things, small attractor patterns in darker colors are working the best, especially if they've got a good amount of flash. Mayfly patterns are also doing pretty well. We're in a weird transition period right now; it will get better as fish settle into the fall weather and cooler water temps!

Dry Flies - Winna Spinna, Ant Acid, Arricks Flying Ant, Parachute Adams, Longhorn Beetle
Nymphs - Olive Hot Spot, Sunburst Perdigon, BBQ Baetis, Red Neck

Flows/Temperatures (as of September 3rd; click the name for real-time numbers)
Hebgen Outflow - 759.9 CFS

Kirby - 875 CFS
Kirby High/Low Temps - 61/54F

Cameron - 949 CFS
Cameron High/Low Temps - 58/54 F

This Week's Weather Forecast in the Valley

Upper Madison
After the cool weather and rain, the Madison has been revitalized. The highest water temp we've seen in the last few days was 67, and you can tell the difference when fishing. Fish are more eager to eat throughout the day compared to the quick on/off bite windows that were the last month. The only downside in the recent weather is the wind; God bless the guides fighting 45-mile-an-hour gusts in the float section. So make sure to check the wind forecast along with precipitation.
Although the rain did slow the dry fly bite down a bit, fish are still rising to ants, beetles, and the occasional baetis hatch. I've had the most luck with smaller, brown/honey ants drifted close to the banks, or a small chubby with a dropper through the riffles and slicks farther from the banks. Small and shiny droppers have been the best bet, so reach for those dirty perdy's or a crystal dip if rises aren't abundant.

Dry Flies - Winna Spinna, Ant Acid, Arricks Flying Ant, Parachute Adams
Nymphs - Olive Hot Spot, Sunburst Perdigon, BBQ Baetis, Red Neck