Central Texas could experience increased moisture and slightly cooler temperatures as El Niño lingers through the fall and winter, weather forecaster James Greenhaw said in an interview with Community Impact.
According to a report from NOAA, there is an 83% chance that this will be the strongest El Niño on record. Greenhaw, who's known as the "Pflugerville Weather Guy" for sharing updates on social media, explained the effects this natural climate pattern could have on the area.
What is El Niño?
El Niño has been around forever. It was kind of discovered in the early or in the mid-1900s. But basically ... when we have the waters warming, that creates winds that move across the Pacific Ocean from west to east. That also allows some of those warmer winds to move outward and expand. Some of that affects Mexico or Central America and North America. So, the description is hard to exactly say, but it's basically the warming of the Pacific waters west of Central America.
How will El Niño affect Central Texas weather?
In a typical El Niño year, what that does is it brings in more moisture towards the United States, especially toward Texas.
A lot of that Pacific moisture kind of overrides the mountains in Mexico [and] brings us little disturbances sometimes and can generally create more chances for enhanced rainfall, but that doesn’t necessarily happen every time we have an El Niño.
There's a pretty big confusion with that. When people hear the word El Niño, they immediately think we're going to see more rain and we're going to see colder weather. That's not typically the case. When you average all the El Niños that we've had, yes the overall rainfall is a little bit higher than our average, but it doesn't necessarily guarantee that we're going to see flooding rains.
Is there an increased chance of snow or other winter precipitation?
There's a combination effect on that. Just because it's typically cooler doesn't necessarily mean that we're going to have more cold fronts coming in. It just means that because of all the extra cloudiness that we typically see during an El Niño season, it keeps those afternoon high temperatures about 10-15 degrees cooler because we have more cloud cover, possibly more rain.
When we do have those real strong cold fronts come through, usually about three or four per year, yes, we could possibly see ice storms, snow, any kind of freezing precipitation. Typically in an El Niño year, what I've observed is we would see more of a freezing rain, freezing drizzle-type precipitation if we do indeed get below that freezing.
So, it doesn't necessarily mean we're going to see more cold fronts or even stronger arctic cold fronts. It just means that overall the temperatures are going to be just a little bit cooler due to cloud cover.
What’s the timeline of El Niño?
We've actually been in a pretty strong El Niño already. We've been in an El Niño since late spring. In the summertime, El Niño does not affect us at all. Obviously we were pretty dry over summer minus that one July event. Right now we're in a very high El Niño, but the actual effects, when we start seeing it affect us here in Central Texas, doesn't happen until usually very late fall or early winter. So, usually around that November time frame through early spring.
With that said, some of the early forecasts are actually showing that we might not even be in El Niño by the end of spring. We might be more of a neutral or even a La Niña going into next summer. December through I would say March [or] April months are going to be our highest chances to see an increased rainfall. Not necessarily flooding, but it can happen.
Will this affect lake levels in the area?
Most of the lake levels across the area are pretty full because of those July rains that we had. So, that creates a greater concern because if we do end up getting a flood event, there's not a lot of storage left in those lakes for any water to flow into. They're going to have to release water and so that can possibly flood areas downstream.
