Phoenix monsoon season runs from June 15 to September 30 every
year. Those are fixed calendar dates set by the National Weather
Service in 2008. Before that the season was declared by dew point and shifted
around, which is why older Valley residents still argue about when it “really”
starts.
What each part of the season is actually like
June 15 to early July — the dry part
The season is technically open and nothing much happens. This is the hottest,
driest stretch of the year. If you have a marginal tree or a shed that is
already loose, this is the window to deal with it — before
the storms arrive and every crew in the Valley is booked.
Mid July to August — the real season
Moisture arrives and storms start forming over the high ground, then move
into the Valley in the late afternoon and evening. This is when the damage
happens. Wind comes first, often as a haboob, followed by very heavy rain in a
short window.
August is typically the most active month. It is also when associations
start issuing landscaping violations in volume — cleanup requests rise
sharply in the four weeks after the first significant storm.
September — tapering, not stopping
Activity winds down but does not switch off. Some of the most damaging single
storms in Valley history have landed in September. The official end date is a
line on a calendar, not a weather event.
Why the wind matters more than the rain
People plan for the rain and get caught by what comes before it. The
outflow that runs ahead of a collapsing thunderstorm is what takes down palms,
lifts shed roofs and flattens carports. It arrives with very little warning and
is usually over in twenty minutes.
The rain then does the second half of the job. Two to four inches in under
ninety minutes saturates desert soil, and saturated soil is what lets a healthy
tree’s roots give way.
What to do before the season
- Deal with the leaning tree in winter. Non-urgent tree work
is cheapest October through May, and a tree you remove in February is not a
crisis in August. - Check the shed anchors. Metal sheds fail at the fixings
first. - Clear the drains and scuppers. Ninety minutes of rain finds
every blockage you have. - Photograph your yard while it is tidy. A before picture is
useful to an insurer and takes ten seconds.
What to do during it
Bring things down before a storm rather than picking them up after. Shade
sails, umbrellas, light furniture and anything on a roof are all cheaper to
stow than to replace.
If a storm warning is issued and you have something temporary up, take it
down. Monsoon wind will move a shade structure and whatever it is attached to.
Need it cleared? Text photos to 623-263-5172 with your suburb. Wide shot, the access route, and close-ups of anything heavy is enough for a price the same day.