Rain drops are falling on our heads.

Well, that may be a bit of an understatement.

It may be more like rain drops are pounding our heads.

Forecast models call for an atmospheric river to soak California and much of the western United States on Sunday.

Atmospheric rivers are narrow bands in the atmosphere that get their start in tropical areas and have been known to carry up to 25 times the moisture, water if you will, than the Mississippi River does in a day,

Of course to get more clicks on websites, it is breathlessly being called a “bomb cyclone” by some.

Back in the day — think the 1970s when Northern California was ravaged by intense downpours that triggered widespread flooding — the media hype called the weather phenomenon by the less menacing and still accurate term of “Pineapple Express.”

Yes, we are going to get slammed with a lot of water. Yes, some places will get it more than others. And yes, some will queue up the musical score from “Jaws” to give us all a foreboding sense of doom as the great white shark boogeyman whipped up by man’s reckless behavior better known as climate  change is going to bite us big time.

Spoiler alert: Climate change is what has made the world go round for the last 4.54 billion years. Man’s actions do help move the dial. But the best way to get the speedometer back to nature’s pace in terms of being able to weather the changes is for everyone to stop acting like a greenhouse tax or switching to renewables is going to save us all, or more precisely generations somewhere between several to dozens or even hundreds of into the future.

If predictions for Sunday unfold we will see the proverbial perfect storm.

Drought-hardened soil will react as it always does with an onslaught of sudden moisture all at once. It will repel it which means flash flooding.

It’s a little too late to replicate the effect now that we have had a day or so of light to moderate rain, but if you have an area in your yard that has been stripped bare of vegetation with the added element of it being sandy loam you may have gotten an inkling of what is about to happen.

All it required was not to water the area during the past year that has been the second driest on record since they started being kept 170 years ago for California as a whole and then hit it with a stream of water from a garden hose.

You will see water bead, sandy clouds kick up, and water move across the hard ground crust creating areas that are still bone dry even as the flow from the hose is directly aimed at it.

The simple backyard observation would give you an inkling of what can happen. And while the rain of the past few days has provided enough moisture to loosen the compaction that is essentially just scratching the top of the ground, it is still severely compacted literally millimeters below.

It means the ground, especially that not beneath grass and such that is watered two to three times a week, will have the consistency of concrete until moisture seeping down over a period of time is able to undo the compaction.

This is not something that your great-great-great grandfather puttering around California in a Model T Ford in the Dark Ages kick started when we didn’t have seat belts let alone catalytic converters and reformulated gas.

Couple that with thousands of square miles scorched by wildfires over the past few years and we are going to likely have flash flooding and mudslides throughout California. It also means storm retention basins in Manteca will likely be temporarily holding good amounts of water along with a bit of street flooding depending upon where the heavens drops its moisture laden load.

It may be far from catastrophic but you will be told it is a pre-sequel to the main event.

Eventually they will be right.

But here’s the rub that few of those running around with the same urgency as Chicken Little fail to grasp and certainly don’t convey: to reduce damage in the short and medium run whether that’s decades, centuries, or even millenniums as opposed to the long haul requires a different action plan.

Greenhouse gas generated by man clearly needs to be reduced although not necessarily zeroed out. But that doesn’t really address the potential for disasters that are the ones that are the arguably most destructive — floods, drought, and wildfires.

Changing our development patterns are much more critical than trying to snuff out every bit of manmade greenhouse gases on the planet.

It is a case of diminishing returns.

If we stop allowing the wanton urbanization of wildfire zones, stop developing in flood zones unless they have 200-year flood protection, and start earnestly aligning water use habits with the limitations of both water basins and aquifers we will push back more effectively against the onslaught of climate change.

At the same time we as mere mortals must accept the hard cold facts. Eventually the earth will plunge into another glacial age just like the planet will warm. Barring a well-placed hit of a meteor the size of the combined egos of cable TV taking heads and members of Congress or a return to the gas guzzling and polluting days of the 1966 Chevrolet Camaro that got a whopping 5.6 miles per gallon back with gasoline was less than 50 cents a gallon, it will not happen for a long, long, long time.

What most of us will likely take from the days ahead after we take a pounding from whatever happens Sunday will be a hard-core case of blissful denial.

There will be the delusion the drought’s back is being broken.

Yes, it could be the start of the end but based on hydrology going back centuries in what is now the western United States that is about as likely as Congress member Alexandria-Ocasio Cortez one day when she’s old enough being the Republican nominee for president.

The water year that ended on Sept. 30 was the second driest for California since records started being kept 170 years ago. The previous water year was the fifth driest.

The water content from the Sierra snow that was 60 percent of average last water has the equivalent water yield of 2015 when the snowpack was even more dismal. That’s because back to back severe dry years at the higher elevation means the slow snow melt was absorbed by the ground like the bone dry sponge that it is.

Couple that with reservoirs overall in California being at less than a third of average capacity and we have a situation that is more of a deep well that is still going dry as opposed to the proverbial glass being half filled with water.

This is not the time to let down our guard. If anything we need to start using water even more wisely given the only thing likely to lift up from the throes of serious drought in the foreseeable future is weather that only Noah could appreciate.

Enjoy the rain Sunday. Just don’t squander it.

 This column is the opinion of editor, Dennis Wyatt, and does not necessarily represent the opinions of The Bulletin or 209 Multimedia. He can be reached at dwyatt@mantecabulletin.com