Bob... You are not alone. Many of us have often talked about that very thin. Since your adjusted score is used in conjunction with the Course Rating and Slope for the tees you are playing it seems it would only make sense to include weather conditions.
There is potential good news coming in 2019. Although I am not exactly sure how they will implement this, the new world handicapping system notes that an algorithm will account for adverse weather and course conditions to adjust the handicap calculations. This is in addition to a number of other changes including using only 8 of your last 20 instead of 10 games. The thought is that this will make your handicap less volatile.
I can only assume that the Gas will adopt the changes in 2019 :)

That hurts! It is the reason that some guys that I know, refuse to play unless conditions are good. Handicaps are only recorded (for handicap purposes) during the "active season". The active season varies depending on region, province, and even on occasion from club to club.

The purpose of this is to incorporate scores from when playing conditions are typically at their best. From a probability and statistics perspective, if you keep playing rounds of golf, your next bunch of scores should be back to something more "normal" and as such, cancel out your two higher scores that you added (the 11.2 and 16.4 indexes).

Also, the provision of local rules at your club or course can permit things like preferred lies from particularly soft turf conditions, but I find that many courses do not institute that as most recreational players (non-club players) do not maintain handicaps.

Just another note to further my discussion. I played my "second" home course yesterday in a match. Distance is 5600 yards, par 70 from the silver/white tees. Course played more like 6200 yards. We were getting absolutely no roll on our drives. I hit only 3 greens in reg. To compound matters, we enjoyed a 30Km wind that was swirling and always seemed in our face. I usually hit my drives 160-165 carry and depending on winds and dryness, I end up around 180 yards out. Yesterday, I was probably averaging 160, and I was hitting the ball solid, never missed a fairway, never lost a ball. The course is rated at 65.4 and 113 slope. Yesterday, it played like 68 and 130. I only had 26 putts, and shot 79. I missed one makeable putt from 5 feet, but otherwise I can say I did not leave any shots out there and I scrambled beautifully. I made at least 5 putts to win or halve the hole from 6ft or less. So, I card an 13.6 when based on past experience, I really should have been carding a 8 or 9. Handicap is 10.3 this morning. Lost the match 4 and 2 after leading after 9, 2 up. My 17 handicap opponent hit 8 of 9 greens on the back and shot 1 over, I shot 6 over on the back, never hit a green. (he shot 45 on the front). I just could not hit it far enough.