Verasamy attended Silfield Primary School and Framlingham College Junior School Suffolk and King Edward VII School (King's Lynn) in Norfolk where she studied A-Level Geography. She graduated with a BSc (Hons) degree in Geography and Earth Sciences from Brunel University in 2001.
Having previously completed a work experience placement at the Sky Weather Centre before becoming a weather forecaster, Verasamy joined Sky channel and became the regular weather presenter on the Sky News breakfast showSunrise. In 2007 the Sky News website started a feature entitled Climate Clinic - Ask Lucy as part of their Green Britain campaign, where Verasamy answered questions put forward by members of the public regarding climate change. She also contributed to Sky News' The Weather Girls blog.
On 6 September 2010 she joined the newly launched ITV Breakfast programme Daybreak, as a weather forecaster and environment correspondent, alongside Kirsty McCabe. On 7 February 2012, McCabe left the programme, leaving Verasamy the sole weather forecaster. On 2 August 2012 she herself left the programme and now fronts national ITV Weather forecasts for ITV.