so ive been monitoring 20m and 17m pretty closely the last few weeks and something weird is going on. some days i get into europe no problem from the midwest, next day i cant raise anyone beyond a few hundred miles. solar flux has been bouncing around quite a bit and i know that plays into it but i cant always predict when its gonna be good vs garbage.

had a random opening last tuesday around 1800z on 15m that lasted maybe 90 minutes and i worked like 8 or 9 stations in japan and a couple in south korea, which for me is pretty unusual. then the next morning 15m was dead as a doornail. been trying to track the sfi and kp index more carefully but honestly its still kind of a black box to me. does anyone have a good way to predict when these openings are gonna happen or is it just a matter of being in the right place at the right time and having the radio on?

yeah 15m has been doing some weird stuff lately, i noticed the same thing. those short openings to the pacific are classic when the flux is marginal — like you'll get a window when the greyline lines up just right and then poof its gone. honestly the best tool ive found besides just watching the sfi on sites like dxmaps or the solar ham site is to watch the cluster spots. when you start seeing DX spots popping up on a band that looked dead, that's usually your cue to get on quick because it wont last long. the kp index matters a lot too — anything above like 4 or 5 and you can basically forget about the higher bands for long path stuff, the absorption just kills it.

that JP run sounds nice though, 15m to japan from the midwest on a marginal flux day is pretty solid. you were probably riding a brief enhancement. keep a log of the conditions when that happens and youll start to see patterns over time, it takes a while but it becomes almost like a sixth sense after a few years of paying attention.

im pretty new to all this propagation stuff too so take this with a grain of salt but i started using the DX toolkit app on my phone and it shows solar data, the A and K indices, all that. i dont fully understand everything it shows yet but it helped me figure out why some days i just couldnt reach anybody. my elmer told me to check the flux index first thing in the morning and if its below like 100 the higher bands are gonna be rough — not impossible but rough. above 150 and apparently things get pretty exciting on 10m and up. havent personally experienced a good 10m opening yet since i just got licenced in spring but i keep checking.