Less moisture this weekend before a weaker monsoon is re-established for next week
Thursday, August 7, 2014
Lingering moisture from the monsoonal surge this past week will keep the threat of storms for this afternoon, though the wet pattern will be reduced for much of the weekend as some dry air from the desert southwest moves over the area.
However, subtle waves in the mean flow will keep some threat of showers over the area, especially in the afternoons. Additionally, a weak wave moving along the Canadian border will increase the forcing Saturday afternoon and suppress the drier air southward for some possibly stronger storms then.
A piece of this wave will be left behind along the central west coast by late in the weekend, re-establishing the moist monsoonal pattern as southerly flow ahead of the wave drags up more moisture. This lingering wave is forecast to move over us sometime around Wednesday and Thursday, increasing the chance of more wetting rains.
This wave then phases with another wave well to our north as it moves east of us last in the workweek, carving out a longwave trough in the Great Plains and leaving us with a rapidly building ridge to our west. This scenario should lead to dry conditions heading into the following weekend, with seasonably cool temperatures as we will be in close proximity to the much cooler airmass to our east.