Hurricanes and the monsoon

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A hurricane in 2014 forced schools to close and vehicles were flooded on freeways in the Valley. (Source: 3TV/CBS 5) A hurricane in 2014 forced schools to close and vehicles were flooded on freeways in the Valley. (Source: 3TV/CBS 5)
(3TV/CBS 5) -

Monsoon season is our most active time of year for weather in Arizona. 

Monsoon means “season” and signifies a seasonal shift in wind that brings moisture into our region from the south and east, rather than the normally dry air we get from the westerlies.

[SPECIAL SECTION: Arizona Monsoon 2017]

But during the months of August and September, we occasionally get an extra “boost” of moisture from the tropics. As hurricane season ramps up in the eastern Pacific, storms that hit western Mexico and the Baja Peninsula sometimes push additional moisture toward Arizona. While we don’t get the actual “hurricanes” or “tropical storms,” their remnants can mean a mess for Arizona.

[RELATED: Hurricanes: Storms like no other]

Remember that storm in September of 2014 that put freeways underwater, closed schools for the day and flooded entire neighborhoods? That was a result of the remnants of Hurricane Norbert. 

[READ MORE: Mesa mayor: Flooding looks like a 'mini-Katrina' (Sept. 5, 2014)]

It set a record for our wettest day EVER in the Valley! We picked up 3.30 inches of rain that day, much of it overnight and into the early morning hours. We picked up 5.11 inches of rain that September and that monsoon season totaled 6.34 inches, our seventh-wettest on record.

[SPECIAL SECTION: Weather blogs]

MOBILE/APP USERS:  Click here to see ADOT's image of freeways underwater after the 9/8/14 storm

Occasionally, tropical systems in the Atlantic can impact Arizona with moisture, but mainly we look to the storms in the eastern Pacific that can leave us with a “juiced up” atmosphere. 

That boost of moisture increases the threat for heavy rain. We’re most at risk for this in August and September, so count on the 3TV and CBS5 team of meteorologists to keep you updated through the rest of monsoon AND hurricane season!

3TV and CBS 5 meteorologists on Twitter

@AshleeDeMartino | @PaulHortonCBS5 | @royalnorman | @KimQuintero | @SchwartzTV | @aprilwarnecke 

[azfamily.com Weather Tools: Rain Totals | Interactive Radar | Blog: Weather Discussion | Alerts/Warnings | 360 Camera Network]

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Copyright 2017 KPHO/KTVK (KPHO Broadcasting Corporation). All rights reserved.


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