By Erin Jordan - bio | email | Facebook | Twitter
TUCSON, AZ (KOLD) - The monsoon is on a break.
Although
the monsoon was off to a slow start, the past few weeks have pushed
rain totals up to near average at the Tucson International Airport.
Douglas, Sierra Vista, Willcox, and Fort Thomas are running above average.
This week the chances of monsoon storms are low because of a trough hanging out over the west coast.
A trough is a dip in the jet stream, which allows cool, dry air from the north to flow south.
Southeast Arizona is on the eastern edge of the trough.
This is close enough to for the moist tropical air present from the bottom to the top of the atmosphere to be displaced to the east.
While the dew points at the surface are still in the 50s and 60s, dry air high up in the atmosphere is gobbling up most of the moisture rising during the heat of the day.
This kills the monsoon storms.
Later this week, the trough weakens and slowly heads north.
Unfortunately, high pressure is forecasted to build right over southern Arizona.
High pressure means there is sinking air at the center of the system, which is not favorable for storm development, which needs rising air.
It's going to be hot and still humid with little relief from the heat.
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