While at high school McCabe was an early member of the Palace Youth Theatre which was a joint venture between Kilmarnock and Loudoun District Council and Borderline Theatre Company. During this time she played roles in many stage productions including Alice in “Alice in Wonderland” and performed as a solo singer on many occasions, notably performing John Lennon’s “Imagine” in the 1993 production of “Summertime Blues”.
McCabe studied Geophysics at the University of Edinburgh, graduating with a first class honours degree before going on to spend three months as an intern at NASA’s Goddard Space Flight Center in Maryland, where she used satellite magnetic data to interpret the underlying crustal structure of parts of Australasia. Further study at the University of Oxford saw her involved in a project to look for evidence of climate change in old volcanic soils on the Greek island of Santorini (Thera). While at Oxford she was elected President of the Jesus College Graduate Common Room. During her time at Oxford she was offered a three-month internship at New Scientist magazine where she went on to work as a sub-editor for four years.
McCabe joined the BBC Weather team in September 2003 and started her training on new media forecasts working on the BBC Digital’s interactive service and online. She completed the first part of her forecaster training at the Met Office College in 2004 and her advanced forecaster exams in 2005. She then presented forecasts across a number of BBC outlets, including BBC News, BBC Radio 4, BBC World News and BBC One. McCabe was a main weather presenter for BBC News at Ten and occasionally presented the weather on the BBC News at One.
In January 2006, Kirsty briefly gained some measure of notoriety in Scotland following a forecast where she told Rangers FC fans heading to their game to “wrap up warm if they are heading for Castle Grayskull”. (Castle Grayskull is often used as a derogatory term for Ibrox Stadium by opposing football fans).
In November 2008, it was announced that she would be replacing Andrea McLean as GMTV’s weather forecaster. In September 2010, McCabe joined GMTV’s replacement Daybreak as a weather presenter and environment correspondent alongside Lucy Verasamy.
McCabe married South African architect Renato Marchio in July 2008. On GMTV on 28 June 2010 she announced that she was expecting a baby at the end of the year. She gave birth to a baby boy named Ethan.