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We obtained broadband and narrowband images of the hyperactive comet46P/Wirtanen on 33~nights during its 2018/2019 apparition, when the comet madean historic close approach to the Earth. With our extensive coverage, weinvestigated the temporal behavior of the comet on both seasonal and rotationaltimescales. CN observations were used to explore the coma morphology, revealingthat there are two primary active areas that produce spiral structures. Thedirection of rotation of these structures changes from pre- to post-perihelion,indicating that the Earth crossed the comet's equatorial plane sometime aroundperihelion. We also used the CN images to create photometric lightcurves thatconsistently show two peaks in the activity, confirming the two source regions.We measured the nucleus' apparent rotation period at a number of epochs usingboth the morphology and the lightcurves. These results all show that therotation period is continuously changing throughout our observation window,increasing from 8.98~hr in early November to 9.14~hr around perihelion and thendecreasing again to 8.94~hr in February. Although the geometry changes rapidlyaround perihelion, the period changes cannot primarily be due to synodiceffects. The repetition of structures in the coma, both within a night and fromnight-to-night, strongly suggests the nucleus is in a near-simple rotationstate. We also detected two outbursts, one on December~12 and the other onJanuary~28. Using apparent velocities of the ejecta in these events,68$\pm$5~m~s$^{-1}$ and 162$\pm$15~m~s$^{-1}$, respectively, we derived starttimes of 2018~December~12 at 00:13~UT~$\pm$7~min and 2019~January~27 at20:01~UT~$\pm$30~min.

Narrowband Observations of Comet 46P/Wirtanen During Its Exceptional Apparition of 2018/19 I: Apparent Rotation Period and Outbursts