Changes in Jupiter's Zonal Wind Profile preceding and during the Juno mission

- Downloadable text tables give 5 zonal wind profiles from HST/WFC3 images.
- Epochs of data are: 2016.95 (Juno PJ3), 2016.11, 2015.05, 2012.72, and 2009.72.
- Average global uncertainties are 5-6 m/s, smaller than in past similar studies.
- The 24°N jet peak speed decreases following plume outbreaks in 2012 and 2016.
- The brightness of the NTB also decreases following these plume outbreaks.

We present five epochs of WFC3 HST Jupiter observations taken between 2009-2016 and extract global zonal wind profiles for each epoch. Jupiter's zonal wind field is globally stable throughout these years, but significant variations in certain latitude regions persist. We find that the largest uncertainties in the wind field are due to vortices or hot-spots, and show residual maps which identify the strongest vortex flows. The strongest year-to-year variation in the zonal wind profiles is the 24°N jet peak. Numerous plume outbreaks have been observed in the Northern Temperate Belt and are associated with decreases in the zonal velocity and brightness. We show that the 24°N jet peak velocity and brightness decreased in 2012 and again in late 2016, following outbreaks during these years. Our February 2016 zonal wind profile was the last highly spatially resolved measurement prior to Juno's first science observations. The final 2016 data were taken in conjunction with Juno's perijove 3 pass on 11 December 2016, and show the zonal wind profile following the plume outbreak at 24°N in October 2016.