Unknown flying object seen in Oregon

Report from MUFON:

Date of event: June 15, 2010
Location of event: Salem, Oregon

"We took the kids to the playground at River Road Park in North Salem (River Road/N. Broadway); arrived just after 2 PM. Watched them play for a few minutes, looked SSW at the clouds: mostly billowy storm clouds--heavy rains on and off during the past couple of hours, with/periodic showers starting earlier in the day.

First noticed a hawk's nest in a tree at the same direction, about 100 feet off the ground: one bird left the nest and circled, the other bird remained to watch the nest; first bird returned a couple of times. My kids and I watched the birds/nest directly for about five minutes, then they played and I watched them. Periodically, I looked at both the hawk's nest and the coming storm clouds while the kids played. At one point, directly above the nest by several feet (approximate, based on distance from ground), I noticed what I first thought was a balloon.

It rose very slowly in the sky towards the clouds. Several things immediately stood out: object was black, was at first spherical in shape, but appeared to almost change into an egg/oval shape as it moved, heavy winds were blowing storm clouds from the SSW to W very quickly--but the object continued to move directly up as if moving against the wind. I watched it move slowly and directly upwards, seeming to 'change' between sphere and oval, for at least four/five minutes, still entirely against the wind. It then stopped, and stayed stationary for about a minute (definitely not as long as the upwards movement); very dark storm clouds were quickly approaching it, but its own dark color stood in contrast to the clouds.

Then the object moved horizontally--positioning to WNW--at an incredible speed, and disappeared into the cloud bank. I watched for at least a couple of minutes to see if it emerged out of the cloud bank--the wind was moving the clouds quickly--but saw nothing further.

Again, at first thought it was a balloon, like one of the large ones used by car dealerships to draw attention, but there are none in that part of town--or across the river (Willamette), for that matter, nor was there a tether seen. Too, from the apparent distance from the ground--perhaps several miles--the likely size of it would've made it unlikely to be a commercial balloon. But the general fact of it moving in a straight line upwards AGAINST fairly heavy winds for several minutes negated that it was a balloon; too was the fact that it stopped/remained stationary for at least a minute AGAINST fairly heavy winds.

And finally the fact that it moved AGAINST fairly heavy winds at a high rate of speed into an approaching cloud bank made it unlikely that it was a balloon. I'm not entirely convinced of what I saw. Just the distances and weather patterns converging concurrently make me feel that a light object like a balloon wouldn't have functioned/moved in the manner that it did. But similarly, perhaps the weather patterns and distances at the time made an ordinary object appear to act extraordinarily.

There is a National Guard airbase in town, and perhaps they do conduct weather experiments...but the base is several miles away in the opposite direction. It's been many years since I took a science class, so perhaps there's a logical explanation (i.e., optical illusion, theory of physics) for why something moved the way it did for the duration it did... but thought I'd post this in case someone else in Salem, OR might have seen the same thing..."