Arctic air will filter south and east through early this week. As this cold air moves across the South, a rare winter storm is forecast to develop from Texas, Gulf Coast States into the Southeast through early this week. Several new daily record low temperatures are expected, including new record-low maximum temperatures. For Southern California, fire weather concerns increase this week. Read More >
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A wide swath of 3-6 inches of extremely heavy rain (3-6 inches) fell along the Mogollon Rim south of I-40 from Ash Fork to Parks during the afternoon and early evening of August 18th. The flooding rain moved south through various canyons and washes including Sycamore Creek before emptying into the Verde River east of Paulden. A major flood wave moved through the Verde River gauge at Clarkdale around 9 pm that night with a rise from 1.91 feet to 19.49 feet (32,047 cfs) in 58 minutes. This was second highest crest on this gauge in history. Significant flooding was noted along the river in Clarkdale and Cottonwood as the flood waters passed through. The water moved through the Verde River system overnight into Thursday with rises of several feet noted on the gauges near Camp Verde and above Horseshoe Dam. The water reached the Camp Verde gauge around 9:30 am MST Thursday morning and the Horseshoe Dam gauge on Thursday afternoon. Additional minor flooding of property was reported in Camp Verde.
Wednesday and Thursday August 18-19, 2021
Deep monsoonal moisture was in place across northern Arizona, especially south of the Mogollon Rim. A trough passing to the north of the region provided additional dynamics and lift for widespread shower and thunderstorm activity. Steering flow was toward the northeast with multiple rounds of storms forming across southwest and central Yavapai County before moving over the area near the Rafael Fire Scar. Antecedent conditions also likely played a role as a very wet start to the 2021 Monsoon season may have led to more runoff than usual.
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