Texas Tech University

Mailbag: Let's Talk About the Weather

Allen Ramsey

August 18, 2023

Fake fall came and went, but we learned some things.

Welcome back to the Mailbag!

Wasn't it nice earlier this week when the temperatures here in lovely old Lubbock town hit a point that was reasonably comfortable for a few days in a row?

Around here – and honestly across most of the south – that's known as false fall. If any of you were confused as to what that was, the temps the last couple of days were a strong reminder that your air conditioning unit still has some work to do.  

This summer has been one for the books already, and it's not over just yet.

But the shift in temps got us talking about the weather again. Honestly, we spend most of the summer trying not to talk about it in hopes if we don't say anything maybe the 100-degree days will go away.

With that in mind, today in the Mailbag we're going to go in on a weather topic we started leaning into early in the summer and then put on the back burner while the sun burner was on high.

Today's topics are rain in Lubbock, heat domes, and why Karin and Paul, who both work in my office, got water for their lawns but mine was left bone dry.

Now, any loyal reader of the Mailbag probably knows how we do this, but for those of you new to this column, don't be scared, we reach out to actual experts to get answers and don't just make'em up as we go.

Luckily for us – and you – Texas Tech University has exactly the expert we needed to talk about this. His name is Sandip Pal.


Pal is an assistant professor in the Department of Geosciences. His research involves both atmospheric measurements and numerical simulations. He's also one of the leading experts in the U.S. when it comes to heat domes over smaller cities and how they impact weather patterns. In one funded research project in particular, he advocated for the idea that “smaller-sized cities matter.”

And, if we can be honest for a second, he is one of the most fun interviews we've ever had.

The day we went to Pal's office he prepared a slideshow for us to explain the concepts we were asking about. And it was awesome.

Basically, we were wondering why rain seems to miss Lubbock so often, and why certain parts of the city get more sky water than others.

With a map of Lubbock up on the screen, Pal gave us a rundown of how Lubbock's urban dome works and why research into the urban domes of small cities is important.

So, for the next few hundred words, we're going to try and relay that information to you in a consumable way.

It starts with this explanation.

“Rain doesn't come from water vapor alone,” Pal said. “There are three things we need to make rain. We need the appropriate amount of water vapor, the correct amount and type of aerosol particles to form the cloud, and very unstable conditions in the atmosphere to make the storm.

“Aerosols and dust particles are very complicated due to their high variability in both space and time. They help make the clouds, but when it rains, they go away. Rain cleans the atmosphere (i.e., washout effect) and so after it rains you often see a bright sky because the dust is gone. So aerosols help make the rain, but the rain removes them as well, and the cycle goes on.”

The dust that helps build systems in the Lubbock area is often accumulated from New Mexico and/or the Mexican Plateau, picked up as winds sweep southeast from the mountains with the jet stream. The systems gather dust and moisture as they head into Texas, looking for a spark to bring all three conditions together.

And this is where it gets interesting.

Weather Equipment

Cities like Lubbock, smaller urban centers within the expanse of the plains, often cause that spark and bring the unstable conditions needed to ignite a storm system.

When you picture a map of Lubbock you see Loop 289 and most people would assume the city center falls somewhere near the Heart of Lubbock neighborhood, which is roughly in the middle.

In truth, the center of Lubbock, at least in terms of the heat produced, lands somewhere near the junction of the loop and Spur 327 while the part of Lubbock east of I-27 is almost rural even though a major part of it is inside the loop. Understanding that is critical in understanding how storm systems react when they reach Lubbock.

The urban heat dome – the one centered roughly over Home Depot down on the loop – pushes clouds away from it. Those clouds condense and leave the system with three possible outcomes explaining how urbanization modifies rainfall distributions within and around a city.

“If the storm comes here, it has three possibilities,” Pal explained. “It will rain over Lubbock, it will go beyond Lubbock (downwind enhancement), or it gets split into multiple systems (precipitation bifurcation or bifurcating thunderstorms). These three conditions will happen in three different situations.”

Time of day and the difference in temperature between Lubbock's city center and the surrounding area is a major factor. The difference between the heat of the city center and the surrounding area is less stark in the evening and at night. But, during the day, the concrete is hot enough to cook an egg. The impact of the urban heat effect on rain could be either enhancement or initiation of rain depending on the city itself and the surrounding rural and suburban areas.

The types of aerosols in the atmosphere and the amount of moisture available also play key roles in when and where the storms hit. For instance, the day after a rainstorm in Lubbock, temperatures are generally lower and more moisture is available, making it more likely a second rain event will happen.

“We call it convergence,” Pal said. “Convergence can be created by moisture, or if you have warmer and cooler air masses mixing together. If you have an urbanized location and a rural location near each other, that will also create convergence because rural locations will have more moisture due to more vegetation cover there.

“These are the conditions that set up whether we will have a storm that hits over Lubbock or not.”

The hard part, of course, is predicting how the conditions will align in the future, which is why meteorologists struggle so much in predicting where rain will fall.

There's also the complexity of Lubbock producing its own rainstorms.

“It's basically a locally generated storm, like Lubbock creating its own rain,” Pal said. “Lubbock has its own moisture, has its own dust, has its own instability. And those are the hardest to pick and forecast.”

Being in an arid region makes these forecasts even harder, but the research being done by Pal's group focuses on meteorological processes over arid regions.

A glance at the West Texas Mesonet will show vastly different rainfall amounts from different parts of Lubbock. For instance, in May alone the rain measurements varied between nearly 8 inches of rain just north of Lubbock, to fewer than 5 inches of rain near the city center.  

That pattern is harder to pick out in months like June and July, when it decided to be hot every day and never rain, but the sporadic nature of when and where the rain hit is easier to understand once the conditions were explained.  

Pal, for his part, is trying to find answers to all these questions. He's working on projects for places like NASA and trying to develop more advanced observational platforms to assist in developing weather prediction models that could potentially change the way people consume weather forecasts.

A lot of the work is still in its early stages, few researchers in his field focus on the impact smaller cities like Lubbock have on the weather.  

At its peak, his work could help provide more safety for people living in smaller cities and the towns and rural areas around them, travelers looking for better information on the weather along their traveling route and better predictions for those of us living in smaller cities.  

Honestly, we're looking forward to learning more, and we'll be checking back in with Pal over the coming months and years to see what other cool stuff he can teach us.  

For now, we hope this helps you better understand the highly variable weather in Lubbock, how we end up with four seasons in a day, and why it never rains at my house but Paul and Karin's yards get plenty of sky water.

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