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Eclipse mapping is an observational technique that uniquely measures an exoplanet.s thermal structure as a function of both latitude and longitude. Multiwavelength eclipse maps provide an unprecedented view of a planet.s three-dimensional dynamics comma thermal structure comma chemistry comma and energetics. Here we propose to produce the first spectroscopic eclipse map of an exoplanet via observations of the best-studied hot Jupiter comma HD 189733b comma from 1.1-1.7 microns with WFC3-G141. These observations will measure the geographic distribution of dayside emission over these wavelengths comma thereby constraining the global circulation patterns and relevant atmospheric timescales in HD 189733b with latitude comma longitude and altitude. When combined with published Spitzer-IRAC mid-IR photometric phase curves and eclipse maps comma our proposed WFC3 spectroscopic eclipse maps will paint the most detailed and complete picture to date of weather deep in a hot Jupiter atmosphere comma refining general circulation models that aim to predict their climate. In addition comma our proposed eclipse mapping observations will serve as the foundation upon which future observational and theoretical frameworks will interpret future spectroscopic eclipse maps with HST and of considerably smaller and cooler planets with JWST.