MONSOON MESS: Why meteorologists face a dilemma this season

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Mother Nature teased the Valley with storms on the outskirts of greater Phoenix on July 6, 2017.(Source: Michael Hartrumph) Mother Nature teased the Valley with storms on the outskirts of greater Phoenix on July 6, 2017.(Source: Michael Hartrumph)
(3TV/CBS 5) -

Phoenix meteorologists tend to be the most hated people during the monsoon. 

If I had a dollar for every email, Facebook message and tweet that said something along the lines of "why can't you ever get the forecast right?" or "you're the only one who can keep their job after getting it wrong," I'd be a rich woman.

Arizona during the monsoon can be one of the most challenging areas for which to forecast the weather. A big reason why is because one of the most important tools meteorologists use to track storms is thrown for a loop this time of year.

[SPECIAL SECTION: Monsoon 2017]

A couple years ago, I spoke with Randy Cerveny, a professor of geographical sciences at Arizona State University about this very matter.

"The monsoon time is where meteorologists earn our bucks because it's the hardest kind of forecasting that you can possibly do," Cerveny said.

Cerveny, author of "Weather's Greatest Mysteries Solved!," discussed the important role special computer programs called weather models play in predicting the weather.

"In order to understand how temperature and wind and pressure all change, you can write those as mathematical equations," he explained. "A weather model is simply the massive equations that are used to find out what will happen to the weather."

There is an array of models that research institutions have created, and every day, the 3TV and CBS 5 forecasters time out when storms are going to hit your neighborhood using models depicted in Futurecast.

[RELATED: Monsoon season: The dew point dilemma]

While these models can be incredibly accurate most of the year, they don't handle the monsoon very well.

"One of the biggest problems we have with weather models has to do with the fact that in order to get them to run, you actually have to have information to start with," Cerveny said.

That information comes from weather observation sites like the National Weather Service office in Phoenix, where elements like temperatures, winds and dew points are measured. But these weather sites are few and far between.

"Our ability to forecast is only as good as what we can currently observe in terms of our weather," Cerveny said. "If we wanted to have great models, what we would need to do is to have weather stations on every block. We don't have anything close to that."

Unlike large cold fronts that swing in from the west and can cover large areas measured by multiple observation stations, Arizona's monsoon storms are convective and very small in size. 

"They're based off of surface heating, and surface heating can be very localized," Cerveny explained. "Some parts of the Valley can heat up more than others, and that may be a part of the Valley where we get some more buildups, and the other part of the Valley doesn't."

What's more, the models can't read surface heating very well, which sometimes means surprise rain showers or perhaps no rain at all when the models suggested an active monsoon day. 

[READ MORE: Monsoon Season 101]

But, these forecasting models continue to improve with time.

"Back 400 years ago, if you made a forecast, you were burned at the stake," Cerveny said. "So, we've come a long way, but we're not perfect."

[SPECIAL SECTION: Weather Blog]

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