the monsoon brings welcome rains and relief from the summer heat, the thunderstorms
that come with the monsoon bring their own hazards. In fact, this is the
most dangerous time of year weather-wise in Arizona. So before the season
gets underway, it is a very good idea to review these safety tips:
- If you hear thunder,
you are close enough to a storm to be struck by lightning. Go to a safe
place immediately! The safest locations are sturdy buildings and hard-topped
vehicles. Wait there until 30 minutes AFTER the last rumble of thunder
- Get away from open
areas, including armadas, porches, trees, convertible cars, swimming
pools, and open areas.
- Plan outdoor activities
to avoid being outside between mid afternoon and mid evening, especially
in higher elevations where lightning is more common.
- Do not touch any
wires or plumbing inside a building
- Remember that it
does not have to be raining for you to be struck by lightning.
- Lightning can strikes
up to 60 miles away from the nearest rainfall!
- Bring pets indoors.
Lightning and thunder are very scary for pets, and they are likely to
panic or even run away to try and escape the storm.
- If someone is struck
by lightning, call 911 immediately
- Unlike other parts
of the country, thunderstorm wind gusts here in Arizona almost always
exceed 40 mph. The strongest straight line wind gusts can exceed 100
mph, and can produce damage similar to a tornado! Anytime a thunderstorm
approaches, no matter how weak it seems, move indoors to avoid flying
debris. Winds rushing down from a thunderstorm can develop very quickly.
- When a Severe Thunderstorm
Warning is in effect, it means damaging wind gusts of 60mph or higher
are likely. Move into a central interior room. Stay away from windows.
- Unanchored mobile
homes are NOT safe in any severe thunderstorms, and even anchored mobile
homes can be heavily damaged in winds over 80 mph. Move to a more sturdy
- Stay away from
trees. The vast majority of people are killed or injured in severe thunderstorms
by trees falling on them, from flying debris, or from downed power lines.
- Never touch a downed
power line, even if it appears dead. Assume that it is live. Call for
- Straight line winds
can travel dozens of miles away from the thunderstorm that produced
them. If the wind suddenly shifts and blows toward you from an approaching
storm, while the temperature either becomes much colder or much hotter,
the winds are likely to become even stronger. Move indoors!
- Before the monsoon
season, it is a good idea to either secure loose outdoor furniture and
garbage cans, or move them indoors. These are frequently blown around
in our summer thunderstorms - even the weakest ones.
- These are an underrated killer in Arizona! Straight lines winds in
any thunderstorm can lift huge clouds of dust and reduce visibilities
to near zero in seconds, which can quickly result in deadly, multi-vehicle
accidents on roadways.
- Dust storms are more common in the early part of the monsoon, near
agricultural areas, and near Willcox Playa in Cochise County. Use caution
in these areas any time thunderstorms are nearby.
- If you encounter a dust storm, pull off the road immediately. Turn
off your headlights and taillights, put your vehicle in "PARK,"
and take your foot off the brake. Other motorists may tend to follow
taillights in an attempt to get through the dust storm, and may strike
your vehicle from behind.
- Dust storms usually last a few minutes, and up to an hour at most.
Stay where you are until the dust storm passes.
- Flash floods are
common in Arizona. There are thousands of low water crossing and dips
which flood every summer. Know where they are, and avoid them during
- Never ever drive
into a flooded roadway. The water depth is very easy to misjudge, and
the road itself may be damaged or destroyed underneath. It only takes
about 1 to 2 feet of water to float most vehicles, including SUVs.
- Never drive around
barricades. They are there for a reason - usually because flash flooding
is about to take place, is already happening or the road is damaged
by flooding and is unsafe.
- Never allow children
to play near washes or storm drains after any rainfall, no matter how
light. These flood easily and rapidly, and storm drains are usually
so large that children can be swept away.
- Beware of distant
thunderstorms, especially if they're over mountains. Flash flooding
can occur many miles away from the thunderstorm as the runoff flows
into the valleys and deserts.
- No not camp overnight
near streams during the monsoon. Although many of our thunderstorms
occur during the afternoon and evening, some of our worst flash floods
have occurred in the middle of the night.
- Hikers and mountain
bikers should try to get out earlier in the day to avoid the dangers
of not only flash flooding, but also lightning. Wherever you are hiking
during the monsoon, be aware of your escape routes, follow ranger instructions,
and be prepared to move to higher ground quickly.
- Tornadoes do occur
in Arizona. Unfortunately, many of them here are not detectible by radar
because they are either too small, hidden by interfering mountains,
or develop from the ground up. While they do not last long, they can
occur with little or no warning, and can do considerable damage. If
you see a tornado, which stretches from the clouds all the way down
to the surface, take the same precautions you would for a severe thunderstorm.
Move inside a strong building away from windows. A small, central, interior
room like a bathroom is best.
- Large hail is uncommon
in the deserts and valleys, but more common in the mountains and mid
elevations. If possible, move your vehicle to a carport or garage if
hail is larger than dime size. But do not put your life at risk! Lightning
and straight line winds are far more dangerous than hail.
the monsoon is generally associated with slightly cooler temperatures and
rainfall, excessive heat is still by far the number-one, weather-related
killer in Arizona. Unfortunately, many heat-related deaths occur during
the monsoon as our typical summertime heat is combined with increased monsoon
humidity. Here are some heat safety tips to keep in mind throughout the
- Drink plenty of
water. It is very easy to become dehydrated in our desert climate without
- Avoid alcoholic
or caffeinated beverages. Both increase stress on the body and actually
- Wear light, loose-fitting
- Stay out of the
- Shift strenuous
outdoor activities too cooler parts of the day, especially during the
- Check on elderly
friends, neighbors and family often. Elders are generally more susceptible
to heat-related illness.
- Take advantage
of air conditioning when possible. Many homes in southern Arizona still
use evaporative cooling (swamp coolers) which are much less effective
during the monsoon.
- If you, or someone
you're with, begins to feel tired and flushed and begin to sweat excessively,
you may be suffering from heat exhaustion. Stop any strenuous activities
immediately, drink more water, and find a cool place to rest.
- If someone becomes
disoriented, stops sweating, has hot dry skin, or even worse, passes
out, that person is probably experiencing heat stroke - a serious medical
condition. Call 911 immediately! If possible, move them to a cooler
- Provide plenty
of water and shade for pets.
it is a very good idea to have a Safety Kit ready in your home!
This is true any time of year, but is especially true during the monsoon
when severe weather is most likely. Your kit should include:
- A flashlight and extra batteries
- A NOAA Weather/All Hazards radio, and/or a battery-operated commercial
- Extra food and water (3 gallons of water per person in your home)
- A first-aid kit
- Canned food and a hand can opener
- Extra clothing and bedding
- An extra set of car keys
- Credit card or cash
- Special items like diapers, baby formula, prescription and essential
medications, extra eyeglasses or hearing aids, and pet supplies.
is a summary of the severe weather watches, warnings and advisories the
National Weather Service issues during the monsoon season:
Thunderstorm Watch: Conditions are favorable for widespread thunderstorms
with damaging winds and even large hail to develop. These are usually issued
only when an especially active day is expected. Watch weather reports and
Thunderstorm Warning: A thunderstorm with damaging winds of 60 mph or
greater is about to occur, or is already underway. These winds could also
produce a dust storm with visibilities below ¼ mile. Hail over 3/4"
in diameter or larger is also possible. Take cover now! Note that heavy
rain doesn't always accompany a severe thunderstorm.
Storm Warning: A dust storm, with visibilities of ¼ mile or less,
is about to strike, or has already developed. Pull off the road now! Wind
gusts between 40 and 60 mph are also likely. If winds associated with a
dust storm are 60 mph or greater, then a Severe Thunderstorm Warning is
Warning: A tornado has been sited and is still on the ground, or is
about to develop based on radar information. Take cover now!
Flood Watch: Conditions are favorable for flash flooding over large
or multiple areas of the region. These are usually issued only when an especially
active day is expected. Watch weather reports and conditions closely.
Flash Flood Warning:
Life-threatening, rapid flooding is about to occur, or is already underway.
Move to higher ground now! It is particularly dangerous to be in a low
lying area or near a wash.
and Small Stream Flood Advisory: Minor flooding is expected or underway
in low lying and flood prone areas. While it may not be life threatening,
extreme caution is advised, particularly for motorists. The same flash flood
safety rules apply.
Weather Outlook: Issued anytime there is a risk of strong winds, heavy
rain, flash flooding, and/or dust storms. These outlooks provide advanced
and detailed information on what the main thunderstorm hazards are expected
to be, how widespread, and when.
is a monsoon? | North American Monsoon
| Gulf Surges | Monsoon
progression | Monsoon Inter-annual
variability | Severe Thunderstorm and
Flash Flooding patterns | Upper
Level Lows and the Monsoon | Monsoon Safety
| For more reading
US Dept of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
Tucson Weather Forecast Office
520 North Park Ave, Suite 304
Tucson, AZ 85719
Tel: (520) 670-6526
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