DENVER -- Dozens of 7NEWS viewers contacted the 24/7 Weather Center Friday morning asking why the storm -- which had been forecast for a week by everyone in town -- didn't turn out as predicted.

Most residents of Colorado are used to the rapidly changing weather, but to go from a forecast of a foot of snow to no snow within just a few hours is tough to understand.

The simple answer is that the forecast track was off-track. All of the computer models and the majority of meteorologists predicted that the storm would be farther north. Instead, it moved 100 miles south of the forecast track.

And this wasn't known until late Thursday evening.

But there's a more detailed explanation.

Observing The Atmosphere

The earth's atmosphere is complicated to not only understand, but explain -- even for a degreed meteorologist.

First and foremost, it is 3-dimensional. You have multiple processes going on from the surface to the top of the troposphere at the same time, about 20 kilometers high in the sky.

The troposphere is where the weather occurs.

As you go up in height, not only does the pressure change, but so do things like temperature and humidity.

Twice each day, the National Weather Service sends up a weather balloon with a radiosonde attached, measuring things like temperature, pressure and moisture from the ground to nearly 100,000 feet in the sky.

Balloons are released from less than 200 locations around North America every 12 hours. Click here to see a map of launch sites.

In Colorado, balloons are released from Denver and Grand Junction each day at 6 a.m. and 6 p.m.

The information gathered from the weather balloons is fed back to computers, plotted on maps and then interpreted for locations in between.

For the most part, it is an efficient process. But when things change rapidly, and you are in between that air sampling window of 6 a.m. and 6 p.m., sometimes a meteorologist can be in for a bit of a surprise.

What Happened With Our Storm?

It's hard to say exactly what happened because you don't have hourly weather data from the upper-atmosphere like you have from thousands of locations at the surface.

The rugged terrain likely played a role in the storm system, as well as the jet stream. The jet stream is a fast band of air that circles the globe, transporting storm systems across the oceans and continents.

There may have been a jet streak that developed, causing the trough of low pressure to dig just a bit further south than previously thought.

A jet streak is a piece of the jet stream that moves faster than the rest of the jet stream. A jet streak would be like if you saw a stream flowing past some rocks or debris in the water, and it speeds up for a time, then smooths out after passing the object.

There could have been bad data somewhere along the way, perhaps a faulty report from a weather balloon.

Was The Forecast Missed?

A missed forecast to one might be calling for cold with snow but it turns out sunny and warm.

To another, a storm that was predicted to form and move into the state misses its mark by 100 miles, might also be a missed forecast.

Regardless, it is weather, and it will do what it does no matter how much technology is developed to try and predict it.

Meteorology is a science, and exciting, because you just never know what could happen -- the old saying, "never say never" comes to mind.

On a very basic level, predicting weather is like dropping a branch in a river and predicting exactly where that branch will be the next day or in several days from now. You have to calculate the current, the eddies, the bank flow, the curves in the bank, etc. Computer models take all of that information and try to calculate an outcome. But tiny mistakes in the data, or gaps in the data, can dramatically change the answer.

The meteorologists of 7NEWS are extremely passionate about their jobs and appreciate all viewer feedback, be it good or bad. We also appreciate those who are curious to learn more about Colorado weather, and invite your questions via e-mail or phone anytime.

Looking Ahead, Another Storm?

There is another storm system sitting over the Gulf of Alaska, and with the current jet stream pattern, it will move toward Colorado. The timing would be early in the coming week, and the direct impacts are still unknown.

If you are making plans over the next few days, look at our 7-Day Forecast on the weather page.

It reflects this next batch of unsettled weather with a warming and drying trend this weekend, followed by a cooler period Monday and Tuesday.