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Relativistic amplification boosts the contribution of the jet base to thetotal emission in blazars, thus making single dish observations useful andpractical to characterise their physical state, particularly during episodes ofenhanced multi-wavelength activity. Following the detection of a new gamma-raysource by Fermi-LAT in July 2017, we observed S4 0444+63 in order to secure itsidentification as a gamma-ray blazar. We conducted observations with theMedicina and Noto radio telescopes at 5, 8, and 24 GHz for a total of 12 epochsbetween 2017 August 1 and 2018 September 22. We carried out the observationswith on-the-fly cross scans and reduced the data with our newly developedCross-scan Analysis Pipeline, which we present here in detail for the firsttime. We found the source to be in an elevated state of emission at radiowavelength, compared to historical values, which lasted for several months. Themaximum luminosity was reached on 2018 May 16 at 24 GHz, with$L_{24}=(1.7\pm0.3)\times10^{27}\ \mathrm{W\,Hz}^{-1}$; the spectral index wasfound to evolve from slightly rising to slightly steep. Besides the newobservations, which have proved to be an effective and efficient tool to securethe identification of the source, additional single dish and very-long-baselineinterferometry data provide further insight on the physics of the source. Weestimate a synchrotron peak frequency $\nu_\mathrm{peak}=10^{12.97}$ Hz and aDoppler factor in excess of $\delta\sim5.0$, with both quantities playing arole in the gamma-ray emission from the source.

A flat-spectrum flare in S4 0444+63 revealed by a new implementation of multi-wavelength single-dish observations