PHOENIX -- After a day of record-breaking heat, Friday could be an active monsoon day.
The National Weather Service issued a Blowing Dust Advisory stretching from the Greater Phoenix area to most of Maricopa County, Pinal County and Pima County. The advisory runs from 2 p.m. to 9 p.m. Friday.
The ridge of high pressure that brought excessive heat to the Valley is repositioning itself towards the east and allowing a southerly flow of monsoon moisture to increase in the state.
Thunderstorms are expected to develop first across Pima County this afternoon. They’re expected to track from the southeast to the northwest. Any storms that develop could produce outflow boundaries that would kick up wind gusts from 35 to 45 mph. Those winds would send dust flying and reduce visibility down to a mile or less. Any outflow boundaries that merge together could produce a haboob. The storm threat would last through this evening.
If storms don’t develop as expected Friday, than Saturday would be a more active monsoon day. If storms do come to life Friday, then Saturday should be quieter.
The high in Phoenix Friday will be less hot than previous days, topping out at 109. Saturday morning’s overnight low will be in the upper 80s.
1215p: First storms of the day in the Phx fcst area over southern Gila Co. Very isolated...but it's a start! #azwx— NWS Phoenix (@NWSPhoenix) July 25, 2014