Upper Henry's Fork
The box is a great option for this weekend. Keep in mind that access is foot traffic or personal pontoon boats that you can drag down to the river. Snow shoes are a good idea. I would have the usual patterns with me. Zebra midges in #16 and #18 brown, red and green. If you’re floating in a pontoon boat the take out is also a bit of a challenge you will have to walk out to the road. The midge fishing on the bottom end of the box canyon has been very good. I would also have streamers. I really like sculpin patterns fished slow or on the swing in the box. Brown, green and tan are my color choices.
Lower Henry's Fork
The lower river is starting to get a little color. From the Chester back water on down the Henrys Fork is big and off color. Keep a close eye on the Warm River to Ashton stretch as well. As of today this section has some color to it but I think it’s fishable and with colder temps in the near future the water will clear up. Ora down to Chester also has a little color but is fishing. Access will not be an issue for you on the lower end. As flies go I don’t have much new info to report. Rubber Legs in black or brown will work well. Have the zebra midges I mentioned above and I would also have some #16 Sawyers. Don’t forget Griffith gnats. #16 and #18.
The Madison remains a great option for early spring fishing. The water has come up a bit but fishing remains excellent. Most folks are fishing between the lakes with good success. A #8 black and tan rubber legs will work very well. I would also have the usual zebra midges with you. Also the tungsten soft spot jig in #16 and tungsten brown stone nymph #8 are my top picks for the Madison.
I think the South Fork is going to be very unpredictable this spring. The flow from the Palisades Dam is up to 16,100 cfs and it will likely get higher. I have heard that by this weekend flows might hit 20,000 cfs.
Same story as the South Fork. While the Teton is a very small river, the current flow in the Teton Valley is about 3 times normal. However, if the weather cools down it could be fishable again before the real runoff starts later in April.