The Henry’s Fork is still in full winter mode and is not red hot by any means.  We are reaching 40 degree temperatures, but nights are still in the mid-teens to low-twenties.
As for what bugs to use:  we’re using #18-22 black or grey midges or Griffiths Gnat.  Pack nymphs; red/black zebra midge, and green caddis.  Streamers would be leeches or sculpins.
If you’re looking to float the river, Warm River to Ashton is your best bet.  Both boat ramps are plowed and are easily accessible.  Ora & Vernon aren’t plowed and you’ll need to bring extra beers to drag your boat…  Chester is plowed and the ice has broken up.  The takeout is only one lane to the restroom and you’ll have to slide out your boat.  The takeaway of all this is to be creative…
Check out our lower henrys fork hatch chart & our real time streamflows.