Joshua Meibos
11/28/11
Clouds Weather Project
The clips in this video are in chronological order, with the first clips from late summer and early fall, then moving into late fall.
Clip 1: August 30th, 1:30 PM. The first clip is the formation and evaporation of fair weather cumulus humilis clouds. These clouds form from a small unstable layer of air topped by a stable layer. This is why these clouds show little vertical development. The winds in this case are westerly.
Clip 2: September 5th, 2:45 PM. The second clip starts out with what appears to be stratocumulus clouds moving east. They are followed by stratus clouds, as well as background clouds moving north. The strange movement and formation of these clouds is probably caused by the mountains: on the other side of the mountains, the winds are moving in different directions, likely southerly, and the uplift of air from the mountains causes additional condensation within the clouds.
Clip 3: September 5th, 3:30 PM. The third clip was taken immediately after the second one was taken, but facing a different direction. The strange cloud forming at first could be a banner cloud forming downwind of Mt. Timpanogos. All of the clouds appear to become stratus clouds midway through, moving east, with high winds and stratocumulus clouds entering at the end.
Clip 4: September 6th, 9:00 AM. This next clip is more cumulus humilis clouds, this time moving south. The clouds moving away from the mountain range soon vanish, as their supply of uplifted moist air is lost.
Clip 5: September 8th, 12:45 PM. This is a giant cumulus congestus cloud over Mt. Timpanogos. The upper air is not unstable enough for it to grow too large, so it fizzles out as it loses moisture and shrinks. Wind at the surface is very light, but there are westerly winds aloft, as can be seen by the cirrus clouds moving from left to right at the end.
Clip 6: October 3rd, 12:30 PM. There are stratocumulus and scattered nimbostratus clouds with a southerly wind and light rain. By the end of the clip, the winds shifted to more southwesterly.
Clip 7: October 6th, 3:30 PM. This is just after the first snow of the year. The snow is now subliming and recondensing into low stratus clouds. The overall winds were northerly, hence the cold temperatures for snow, but there is significant wind shear, with the wind appearing to change directions several times.
Clip 8: October 7th, 12:15 PM. More subliming snow and condensing water vapor. The wind is even stronger this time, and appears to be southerly at the surface. The clouds come so low to the ground that they could be considered fog.
Clip 9: October 8th, 4:00 PM. Southerly winds are blowing cumulus humilis clouds towards Mt. Timpanogos. With the orographic uplift of air, the clouds turn into larger cumulus congestus clouds over the mountain, but fade as the sun sets and the troposphere becomes stable.
Clip 10: November 1st, 1:15 PM. This clip clearly shows the arrival of a cold front. The temperature dropped almost twenty degrees Fahrenheit during the filming of this clip. The lower clouds are being blown by westerly winds, but the upper-level clouds are being blown by more southerly winds, since the front has not reached that high into the air yet. More cumulus clouds form throughout the clip, and gradually become larger.
Clip 11: November 11th, 2:30 PM. The final clip is lenticular clouds! They can only form on the leeward side of mountain peaks. They form when air flows over the peak, and down the other side, and repeating this wavy movement up and down, causing the layers of air above and below it to also move in a vertical wave pattern. At the wave crests, the water vapor condenses in each layer of air, giving the cloud a layered appearance. The fascinating thing about lenticular clouds is that the cloud itself remains stationary, while the westerly winds flow through it.