The figure above indicates the forecasted high in orange (with error bar denoting the range of ensemble forecast members), average high for this time of year in orange (dashed line), forecasted low in blue (with error bar), average low this time of year in blue (dashed line), and forecasted wind speed in purple. Note that the wind speed forecast is sustained wind (not gusts), and it is based on only one model (not an ensemble).
A cut-off low pressure system located over the Eastern Subtropical Pacific will open up into a weak upper-level trough as the large-scale upper-level West Coast ridge in which it is embedded shifts eastward. The trough will move across Arizona on Tuesday morning, and create modest upward motion in advance of the trough. A 20-knot core of southerly winds will develop at lower levels, fueling plentiful moisture and a good chance of rain showers Monday Evening - Tuesday. I expect about 0.3” of rain from this system. Snow levels will be near 9,000’, so snow is out of the question for Prescott.
A second low will cut off just west of Arizona on Thursday – Friday, circulating another more prolonged fetch of moist southerly wind across the state and leading to scattered rain showers that could possibly linger into the coming weekend. Temperatures for the entire week and the coming weekend will generally be above normal.
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Official National Weather Service forecast