Originally Posted by DurangoSteve
It's the persistent "Four Corners High" that is blocking any monsoon flow from coming north.
we are in a westerly flow similar to our winter pattern, a low pressure trough that is being pushed down from the Great Basin.
In the winter this flow brings moisture, but the westerly flow is dry in the summer. the "four courners high" pressure actually needs to build up a bit for monsoons to happen, as it allows moisture from the Gulf of California to flow up from the south. in the winter, this high pressure pushes the westerly flow away.
that's the explanation for down here anyway....
no monsoon in Arizona either.... Verde is almost at record low levels and hasn't been runnable since snow melt....
a bit on the monsoon pattern at the bottom of this article: