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We present new Jansky Very Large Array (VLA) images of the central region ofthe W49A star-forming region at 3.6~cm and at 7~mm at resolutions of 0\farcs15(1650 au) and 0\farcs04 (440 au), respectively. The 3.6~cm data reveal newmorphological detail in the ultracompact \ion{H}{2} region population, as wellas several previously unknown and unresolved sources. In particular, source Ashows elongated, edge-brightened, bipolar lobes, indicative of a collimatedoutflow, and source E is resolved into three spherical components. We alsopresent VLA observations of radio recombination lines at 3.6~cm and 7~mm, andIRAM Northern Extended Millimeter Array (NOEMA) observations at 1.2~mm. Threeof the smallest ultracompact \ion{H}{2} regions (sources A, B2 and G2) all showbroad kinematic linewidths, with $\Delta$V$_{FWHM}\gtrsim$40~km~s$^{-1}$. Amulti-line analysis indicates that broad linewidths remain after correcting forpressure broadening effects, suggesting the presence of supersonic flows.Substantial changes in linewidth over the 21 year time baseline at both 3.6 cmand 7 mm are found for source G2. At 3.6 cm, the linewidth of G2 changed from31.7$\pm$1.8 km s$^{-1}$ to 55.6$\pm$2.7 km s$^{-1}$, an increase of$+$23.9$\pm$3.4 km s$^{-1}$. The G2 source was previously reported to haveshown a 3.6~cm continuum flux density decrease of 40\% between 1994 and 2015.This source sits near the center of a very young bipolar outflow whosevariability may have produced these changes.

Time-Variable Radio Recombination Line Emission in W49A