Monsoon is an interesting little season here in Tucson. It's not a proper season, like summer -- it's only about six to eight weeks long, so it's considered a "mini-season" by climatologists (or at least wikipedia).
At the beginning of monsoon, it's so arid that there will be "rainless" thunderstorms. From the ground, it looks like it's just a lightning storm, but from air, a proper thunderstorm -- the rain drops evaporate before hitting the ground. This, of course, is not a problem this time of year as the monsoon is usually in its third or fourth week, and it's humid enough that the rivers are flowing above ground once more. Lucky me, both this year and last year, I left before the start of monsoon to go travelling, and returned to a turbulent rainless thunderstorm. (I hardly ever get airsick, but monsoon storms are so much worse than normal rain storms with the turbulence that I very nearly lost my lunch both times.)
I somewhat dislike the smell of the rain here. It smells dirty -- but not the clean, fresh dirty of the midwest (or, for that matter, every place else I've lived), where it usually smells like freshly turned dirt and a bit green. It's a dustier scent, almost chokingly so. (For that matter: the tap water also tastes like dust! So I tend to use my water filter way more often than back home, where the water is delicious and non-dusty.) It was great to be outside in the rain in Boston, even though I had no umbrella, because it smelled so nice and clean.
Another interesting monsoon thing is that the clouds have a tendency to just sit in one place and build and build and darken right before a storm -- not at all like the midwest, where you can see them moving around before the rains. (Incidentally, I haven't experienced many cloudy days here.) It's actually kind of cool how quickly and greatly the clouds will grow and darken, as you can see in this four minute video - and not much rain in it!
Yesterday, we had one righteous storm - power was out in parts of the city, there was hail, and it rained so hard that some places had water flowing uphill. That's right, uphill.
Anyway, when I went hiking again this morning (waking up at dark o'thirty so I could be parking my car at 6am, when the trail opened), there was still some standing water on the roads where they dipped a bit, on both of the access roads I have for leaving my apartment complex. The trail was pretty moist too -- not enough to be really muddy, but enough that it was a little squishy in places. The clouds were amazing (the photo up by where I was talking about them was from my morning hike, as is this one, though the first one shows the clouds better; this one is right around the time I was leaving, and it started sprinkling again not too long after I returned to my car), and it was nice and cool. I was surprised by the number of people that were out and about, given that it was 6am that I was hiking. Then again: 6am is probably the best time TO hike out here in the summer - it'll be fairly cool (low-to-mid 70s), unlike the afternoon (where it may be in the upper 90s to low 100s).