Austin, TX UV Index Today
What is the UV index in Austin right now?
2.3 Low
EPA describes low UV as needing no protection for most people.
Today's peak is 8.7 (Very High) at about 1pm local time.
When is UV strongest in Austin today?
UV in Austin peaks at 8.7 (Very High) around 1pm local time (GMT-5). It stays at 6 or above — the high band — for 4 hours, roughly 12pm to 4pm. UV is 3 or above for 7 hours.
Austin today, in numbers
- Latitude
- 30.3°N — 113 of 121 from the north
- Today's peak
- 8.7 (Very High) — 11 of 121 nationally
- Peak arrives
- 1pm local (GMT-5)
- At or above 6
- 4 hours, 12pm to 4pm
- At or above 3
- 7 hours, 10am to 5pm
The window from 12pm to 4pm is the practical answer for Austin today. Nationally today the spread runs 11.4 in Hilo (20°N) to 1.3 in Fargo (47°N). Why latitude and the clock decide this →
An escarpment that adds nothing, a canopy that does
Austin and San Antonio sit less than a degree of latitude apart, so the sun over the two cities is effectively the same sun, and what separates their daily peaks is cloud and shade rather than geometry. At 30.27°N Austin is close to the parallel that runs through Jacksonville, Florida.
The Balcones Escarpment cuts across the city, and it is tempting to credit the western hills with something. It does not amount to much. The city’s elevation is listed at about 600 feet and the highest ground in the metro adds a few hundred more, which is not enough altitude to register. Standing in Westlake rather than East Austin does not change the index.
The same escarpment does change exposure a different way, through shade. West of it the ground carries a dense live oak and juniper woodland, thick enough over the Barton Creek greenbelt that canopy becomes the dominant local variable; east of it the country opens onto blackland prairie and the cover thins. Two people a mile apart at the same hour can be under very different conditions while the city posts one number.
Winter is held down twice over. In NOAA’s Austin sunshine record, which runs from 1965 to 2009, January is the cloudiest month of the year at 50 percent of possible sunshine and December is next at 51, both below the cloudiest month in the equivalent Dallas record. The weeks when the sun is lowest are also the weeks most often overcast.
Nearest metros we model
What does Austin’s UV index mean today?
2.3 is Low. EPA describes low UV as needing no protection for most people. Today Austin also reaches Very High at its peak — a different band from the one it is in right now, which is why the hour matters as much as the day.
Modelled, not measured
The UV figures for Austin are computed by the Copernicus atmosphere model, not read off an instrument here — unlike the AQI on our air-quality pages, which comes from a regulatory monitor. Cloud is where a UV model is weakest. What that means in practice →
Questions about UV in Austin
What is the UV index in Austin today?
When is UV strongest in Austin today?
Is this measured or modelled?
Related
Updated