We’re a month into southern Arizona’s monsoon season.

Supplies of anti-itch cream are growing short as the annual crop of monsoon mosquitoes matures.

Our monsoon mosquitoes are evolving every year.

This year we’ve noticed that the mosquitoes are not being bothered by mosquito repellent because they fly in, hit your skin and fly back really quickly. They do this many times.  One mosquito…many bites.

The other day I was being stalked by a monsoon mosquito who waited until I had a tool in my hands before trying to attack.  By the time I let go with one hand to swat the sucker, she was gone.  I’d put the tool down and the mosquito would just hang back a few feet waiting.

They’ve gotten inside the house and that usually means we will be battling the mosquito invasion until at least October unless we can find every place they have found to breed like the dishes under the house plants.  The outside mosquitoes wait by the doors to get inside.

Eons ago when I lived on the Gulf Coast of Texas we had mosquito nets hanging over our beds. I wonder if one can even buy one of these in Tucson these days. A few more nights of the bedroom mosquito clan and it is going to get really serious.

The pig weed is exploding all over the property. As noted last season, pig weed is also evolving intelligence to evade efforts to eradicate it.  There are lots of other kinds of weeds out there as well. I suppose they have names and purposes in the grand scheme of things. But it is Roundup Time.

Hard to remember the property was devoid of anything green a month ago. Now the stuff is two feet high and it looks like Ireland.

So far this year no leaks in the roof. I have come to hate flat roofs.

If you look around the really older parts of the area…the original adobes that had flat roofs…you see peaked roofs with tin on them.

When the railroad finally arrived in Tucson and tin became widely available, it didn’t take long for people to build new roof structures. We have a mix of Mexican Territorial style buildings with Victorian roof lines.  Keeping rainwater away from adobe is really important. Hooray for tin.

Usually each monsoon we have three really big storms. Lots of flooded washes and motorists getting educated about why there are signs that say “do not enter when flooded“. So far this season most areas have had one rock’em sock’em storm…meaning there’s two more to come.

Down at our end of the valley we’ve had over 3 inches of rain according to the Pima County Flood Control District rain gage report. Most areas on the valley floor have had half that amount. Most of us can expect around 6 inches of rain during the monsoon…so if this is a normal season, a lot more rain is going to fall.

Another monsoon event we haven’t experienced yet this season is the dawn storm…that wakes us all up with the sound of thunder.

The monsoon is the favorite time of most hard core Tucsonans. Spectacular lightning shows. Days starting hot and humid and ending with a Wagnerian symphony that starts with clouds on the horizon, peaks with wind and drenching rain, and fading slowly into the sounds of happy frogs.

This is the most alive time on the Sonoran Desert. Everything is taking advantage of a rare abundance of life-giving water and growing. South of Tucson Interstate 19 has a ribbon of yellow flowers on its edges. The hillsides are turning green…even in the fire damaged areas.

Still to come…a tropical storm or hurricane rainout. The storms form off the coast of Mexico and plow into Arizona…generally at the end of September or early October. One of these years we’re going to get another really big hurricane rainout and remind everyone why people really should not be allowed to build anything in our flood plains.

What is your favorite aspect of the monsoon?
_____________________________________

Do Not Enter When Flooded … a Monsoon Warning

Is pig weed intelligent?

Updated Wednesday June 29, 2011:

First we saw a few little puffs of cloud over the mountains to the south.

Then more clouds each morning.

Sunday we saw the first for real thunderstorm over the mountains in Mexico.

Tuesday June 28th we had thunderstorms over eastern Santa Cruz and Cochise counties.

The dew point Wednesday morning was 52 degrees…up from the 20s a few days ago.

It has been blisteringly hot the last few days…the precursor of the Monsoon. It seems we have to endure temperatures over 110 to suck all that moisture up from Mexico to start the Monsoon.

What is the “monsoon”. The official definition is a seasonal change of the winds.

The Arizona Monsoon may not be like the one that dumps buckets of rain on India…but it is crucial for what we know as the Sonoran Desert.

Our desert depends on two rainy seasons…the winter storms and the summer Monsoon.

One does not have to go too far west where the Monsoon does not regularly reach to see the sudden change in vegetation…or lack thereof.

We have two summers in southern Arizona…hot dry summer in June and then Monsoon summer in July and August and into September.

It used to be the onset of the Monsoon was defined as three consecutive days with dew points over 55 degrees. That was changed to a “seasonal” definition starting June 15 and running into September by the National Weather Service.

I like the 55 degree dewpoint one better.

Old timers know the day the Monsoon arrives…there is a rush of humid air that blankets the valleys and we just feel the difference. It may not rain for a couple of more days…but we know the days of cool nights and effective evaporative cooling is over.

And we know mosquito time is coming soon.

Nights during the Monsoon are spectacular with lightning shows over the mountains.

This year we’re all praying for a lot of rain and no lightning so the forests can be saved.

Tuesday night’s storms sparked three small fires in Santa Cruz County.

Historically the “fire season” really didn’t start until the first dry thunderstorms of the Monsoon set off forest fires.

That has obviously changed, with the fire season starting in March now.

Our forest lands need to be closed much earlier in the summer than in the past because of careless campers and people running around the wild lands that shouldn’t be there who many believe started some of the 2011 fires.

A lesson learned for next season.

Maybe the border will actually be secured by 2012 summer.

Checking the property to make sure roof leaks are repaired and stuff won’t be blown away by the strong winds that come with the Monsoon thunderstorms.

Cleaning out the gutters.

Watching strange colorful bugs scurrying around the mesquite trees.

The entire countryside is begging for the rains to come this season.

One of my favorite web pages is the “forecast discussion” page on the NOAA Tucson Weather web site.

In this discussion, which is updated several times a day, the weather wizards discuss what is looming on the horizon in sometimes difficult technical terminology…but also with remarkable candor.

There are some days that after describing how one model says moisture is increasing and it might rain, and the other model says no way, the forecaster suggests they really don’t know what the heck is going to happen.

The forecast discussion for July 6th 3:47 AM heralds the slow increase in monsoon moisture:

UNSEASONABLY QUIET FOR JULY AGAIN TODAY…WITH DRY AIR STILL RULING THE ROOST. 06Z NAM CONTINUES TRENDS OF PREVIOUS RUNS…SHOWING
INCREASING MIDLEVEL MOISTURE MAINLY SOUTH AND EAST OF TUCSON THIS
AFTERNOON/EVENING…AND EVEN A FEW SPECKS OF QPF NEAR SIERRA
VISTA/HUACHUCA MOUNTAINS. CLEARLY…WILL SEE MORE CUMULUS BUILDUPS
OVER OUR MOUNTAINS TODAY THAN WE HAVE SEEN RECENTLY. SURFACE WILL
REMAIN VERY DRY HOWEVER…WITH DEWPOINTS REMAINING IN THE LOWER 30S
IF NOT MIXING DOWN TO THE UPPER 20S. SOME VIRGA/OUTFLOW POSSIBLE
NEAR THE MOUNTAINS OF COCHISE COUNTY THIS AFTERNOON…BUT KEPT THE
TOKEN POPS LESS THAN 10%. CHANCE OF MEASURABLE RAIN VERY VERY LOW.
WHAT TODAY REPRESENTS IS THE BEGINNING OF A VERY GRADUAL MOISTURE
RETURN PROCESS THAT WILL CONTINUE FOR THE REMAINDER OF THE WEEK INTO
THE WEEKEND…AS HIGH PRESSURE SLOWLY BUT SURELY REORIENTS IN A MORE
FAVORABLE POSITION IN NEW MEXICO/NEAR THE FOUR CORNERS. MOISTURE HAS
BEEN SHOVED QUITE SOME DISTANCE AWAY FROM SOUTHEAST ARIZONA…BUT
WITH TIME IT WILL RETURN…AND WEATHER MUCH MORE TYPICAL OF JULY IS
COMING FOR THE END OF THE WEEK AND WEEKEND.

This is not your television news weather forecast.

It is also fun to look at the water vapor satellite imagery on the Tucson Weather site. One can clearly see the movement of the water vapor flowing over Arizona during the monsoon. The precipitation radar is also cool.

Another good site to follow is the Pima County Flood Control District rainfall page. On this site you can check how much rain has fallen in your neighborhood after a storm.

Of course, one can just go outside…but that’s not as much fun.

Though the monsoon “officially” started on June 15th, the real monsoon is coming soon. That’s when we get slammed with heavy winds, thousands of lightning strikes and drenching rains.

Newcomers to Tucson have no idea what is about to transpire.

One of the things you notice around the area are the “do not enter when flooded” signs. They seem like a joke in the desert…sort of right up there with “no fishing from bridge” signs on the Santa Cruz.

The ”do not enter when flooded” sign is deadly serious.

Every year we have motorists who ignore the “do not enter when flooded” warnings, and drive into a flooded arroyo. Some of them end up dead.

A little background, which will also help you understand Arizona mentality.

Because it only rains 10 or 12 inches a year around here, local governments didn’t want to waste the money putting storm drains under streets and building expensive bridges or culverts over areas that only have running water in them a few hours at a time a few days a year.

Instead, streets were designed for a dual purpose…carrying cars, and draining off storm water to the nearest wash or arroyo or river.

Alvernon north of Speedway, old timers remember, carried up to 2,000 cubic feet per second of water during a storm. If you got caught in a storm on Alvernon, your car could be washed from Speedway to Grant in a few minutes.

All the storm water that falls on the valley floor is hurried to the arroyos, which suddenly fill with water. During a summer thunderstorm which is dropping 2 inches of rain on all those rooftops and parking lots and streets in a few minutes means an awesome amount of water will end up in the nearest arroyo really fast. It is not uncommon to see a three foot wall of water roaring down arroyos in Tucson.

Here’s the deal…it doesn’t take much water flowing over a road to sweep your car away. Water is a powerful force of nature.

Now, as noted, local governments did not spend the money to create “all weather” access in the area, so there are lots of places where water runs over the road during a storm. Dips. Washes…whatever.

There was a big lawsuit over the death of a motorist who ignored a “do not enter when flooded” sign and was swept away to his death.

The survivors of the drowned guy sued saying the warning sign wasn’t sufficient.

The city involved won, on the legal theory called “assumption of risk” meaning you can read, you ignored the sign, and if you die as a consequence, tough luck.

The state went even farther, passing what is called the “stupid motorist act”. This law provides that if you ignore a “do not enter when flooded” sign, and the local police and fire departments have to rescue you, they can (and will) bill you for the cost of that rescue. Fire trucks and ladders and helicopters and all the other emergency response equipment and people it takes to save a stupid motorist are not cheap.

Besides the “do not enter when flooded” signs, it is also common to see barricades at water crossings. Again, remember it is cheaper to run out and put up barricades in front of a place where water is running across a street than to build a culvert. The barricades means the same thing as “do not enter when flooded”.  So driving around the barricades is the same “assumption of risk” with the same consequences.

So when you come up to a “do not enter when flooded” sign and there’s water running, remember two things….if you drive into the water and are swept away and killed, tough luck. If you survive being washed away and are rescued, you will get a bill for thousands of dollars for the rescue effort.

And another thing to remember…the water running over the dip may look like it is only a couple of inches deep and your SUV seems like it could make it across. Wrong thinking. Frequently the storm water erodes the pavement away, so what you think is only a few inches of water is actually a few feet of water. There is no road left under the water.

You have a choice when you come up to a flood wash…wait a few minutes because as fast as the water will fill the wash, it will pass through on its way to Marana. Better to be a few minutes late than dead.