I was driving from south carolina to florida on i-95, and had past savannah, ga. i think i remember seeing jet contrails to the ese, which caused me to look in the sky. that's when i noticed a rectangle shape just sitting up in the sky to the southeast. there were clouds below, and clouds above, but this thing just seemed to hang there between the cloud banks. there were drifting clouds that day - large banks of the big, white puffy kind. cumulus?? so, i told my sister to look but don't remember if she did. it was solid, bright, white. i watched this as much as i could while driving but was surprised it didn't seem to move at all. the clouds did. they kept drifting but this "thing" didn't. we went by some very tall trees that hid it from view briefly then was visible again. after a second set of tall trees i noticed the cloud bank below was rising and covering up the "pillar of white." i couldn't tell if the surface was reflective or glowing, it was just a bright white. i have never seen anything like this - ever! really a sight to see. i tried to get an idea of how big it was; at arms length it was about 3/8" to a half inch tall. it never went horizontal. stayed perfectly straight up and down. so weird. no time to get phone out to video or take a photo. rats. i did look online for weather balloons that were shaped like this but found nothing like this. my husband and i frequently attend mufon meetings and will share this info at the next one.