Heat Burst!

You probably missed it as it occurred around
4:30 AM this morning, but Fargo/Moorhead experienced what is
referred to as a Heat Burst. The temperature already was quite warm, around 80
degrees, but when a thunderstorm just south of Fargo/Moorhead began to decay, a
downdraft formed beneath it, and due to the unstable air in place, the air
accelerated rapidly toward the ground.

The evaporation of rain beneath the
decaying thunderstorm also fueled this downward acceleration. As the downdraft
approached the surface, it warmed and dried which caused the quick increase in
temperature and also a drop in the dew point.

Heat bursts have been known to cause temperatures to rise well over 100
degrees, in our case, the temperature just rose into the low 90s.

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Solstice

June 21st was the Summer Solstice
when the sun’s direct rays were
perpendicular to the Tropic of Cancer, approximately 23.5 degrees north latitude. This put the sun
nearly 67 degrees above the horizon in Fargo/Moorhead at solar noon (a bit past
1:00 PM), the highest of the year. This
compares to the sun reaching a
maximum height of only 19 degrees above the horizon at solar noon on the Winter
Solstice.

It’s this change in sun angle and the corresponding change in energy
received at a given latitude that causes the seasons, not the distance the
earth is from the sun.

In fact, on
July 6th at 7:00 p.m. CDT, the Earth will arrive at aphelion, its farthest
point from the sun in its orbit, at
a distance of 94.5 million miles. Back on January 3rd, Earth was at
perihelion, its closest to the sun,
at a distance of 91.5 million miles.

Cold Air Funnels

Yesterday,  funnel clouds were seen near Langdon
without the presence of a thunderstorm.  As a matter of fact, it was not even
raining in this area at the time of funnel formation.  Where did they come
from?  We refer to these types of funnels as “cold air funnels” because unlike
tornadoes, cold air funnels develop in a shallow cool air mass and often behind
a cold frontal passage.  The warm summer sun will induce air to rise up into the colder
airmass.  This mixing of air in the lower atmosphere with wind blowing in
different directions above the ground may spark the rotation that spins up the
funnel.  If the air is moist
enough and rises enough the condensation funnel will be visible to the naked
eye.  Cold air funnels rarely touch the ground, but have on occasion, so it’s
always best to remain cautious if you see one form.