TL;DR
The Storm Prediction Center has issued a Marginal Risk for severe thunderstorms across southern Arizona, New Mexico, and west Texas today. Isolated severe wind gusts and possibly a tornado or two are expected this afternoon into tonight as a mid-level trough interacts with moisture from the remnants of Hurricane Polo. The main threats are localized damaging winds and brief tornadoes, especially this evening.
What's driving today's severe weather?
A mid- and upper-level low is moving across the Desert Southwest on Tuesday, bringing dynamic lift and strong wind shear to the region. The setup is being enhanced by Hurricane Polo, which moved from the Gulf of California into Sonora, Mexico, this morning.
According to the NOAA Storm Prediction Center (SPC), "While the tropical cyclone is forecast to weaken over the mountainous terrain of northern Mexico later today, a phasing of the mid-level remnants of Polo with the approaching deep mid/upper-level trough will result in a consolidating surface low that is forecast to deepen and move across eastern New Mexico and west Texas tonight."
This combination is creating a very moist environment across the region, with scattered to widespread thunderstorms already underway this morning. As the day progresses, increasing deep-layer wind shear and enlarging low-level hodographs will support storm organization—particularly supercells and organized linear segments capable of producing severe weather.
Where is the Marginal Risk today?
The Marginal Risk area stretches from southern Arizona eastward through southern and eastern New Mexico into west Texas. Key cities in or near the risk area include:
- Tucson, Arizona
- Las Cruces, New Mexico
- Roswell, New Mexico
- El Paso, Texas
- Midland, Texas
The SPC outlook emphasizes that the widespread nature of convection will favor complex or linear storm modes, though "a few/episodic supercells will also be possible."
When will storms be most active?
Thunderstorms are already ongoing this morning across much of the Marginal Risk area. Storm coverage is expected to continue into this afternoon and tonight, with the greatest severe potential arriving this afternoon and evening.
In southern and eastern New Mexico and west Texas, the SPC notes that "a localized tornado and severe-gust threat could accompany any organized storm structures, particularly this afternoon and evening, influenced by a nocturnally strengthening low-level jet."
In southern Arizona, scattered thunderstorms this morning will likely intensify during the day as modest diurnal heating takes hold. The strongest storms are expected during the afternoon hours.
What are the main threats?
Damaging wind gusts
Isolated severe thunderstorm wind gusts are the primary concern today. The widespread storm coverage will encourage storms to merge into clusters or lines, which can produce localized damaging winds even in a marginal severe environment.
Tornadoes
A tornado or two is possible, especially across southern and eastern New Mexico and west Texas this afternoon and evening. The SPC highlights that increasing low-level wind shear and a strengthening low-level jet tonight will support rotating storms. Any tornadoes that do form are expected to be brief and localized, but they can still be dangerous.
Hail
Hail is a secondary threat today. In southern Arizona, the SPC mentions "mostly sub-severe hail" as a possibility with any supercells that develop. Across New Mexico and west Texas, hail is less emphasized due to weak mid-level lapse rates limiting updraft strength.
What does a Marginal Risk mean?
A Marginal Risk is the lowest category on the SPC's five-tier severe weather scale. It indicates that isolated severe storms are possible, but widespread or long-lived severe weather is not expected. In a Marginal Risk, severe storms are typically scattered and short-lived, and many areas within the risk zone may see no severe weather at all.
Even so, any severe thunderstorm can produce damaging winds, large hail, or a tornado. Residents in the risk area should monitor weather conditions throughout the day and be ready to take action if a warning is issued.
What about tomorrow?
Wednesday's outlook is more active. The SPC has issued a Slight Risk—one category higher than today—for portions of Oklahoma, Texas, Kansas, and Nebraska as the surface low deepens and moves into the Central and Southern Plains. Stronger wind shear and better thermodynamic profiles will increase the severe weather potential, including a more organized tornado threat.
We'll have a full breakdown of Wednesday's setup in tomorrow's post.
Last 24 hours: quiet across most of the country
The past 24 hours have been largely quiet. The SPC logged just 1 hail report and 4 wind reports, all in South Dakota and Arizona. No tornadoes were reported. The most notable event was a wind gust of 77 mph recorded 5 miles east-southeast of Kenel, South Dakota, at 1431 UTC, per a public weather station observation logged by the National Weather Service in Aberdeen.
Stay weather-aware today
If you're in southern Arizona, New Mexico, or west Texas, keep an eye on radar this afternoon and evening. Have multiple ways to receive warnings—NOAA Weather Radio, a smartphone weather app, and local news are all good options.
If a tornado warning is issued for your area, move immediately to the lowest floor of a sturdy building, away from windows. Put as many walls as possible between you and the outside.
VORTEX is a free web app at vortexintel.app that monitors severe weather nationwide. Pro ($4.99/month) places phone calls to your phone when a tornado or flash flood warning is issued for a location you care about — calls can ring through Do Not Disturb once you enable Emergency Bypass for the number, unlike most third-party app notifications.