A crowd of more than 700 turned up to watch the Welsh side in a pulsating encounter in the new cross-border tournament featuring teams from Ireland, Scotland and Wales.
The Welsh side produced a much improved and cohesive performance in their third game of the competition and were 17-12 ahead at the break after a dominant first half display.
Captain Alex Callender, once again, led from the front for the Thunder and played a key role in two of her side’s three tries.
But Edinburgh Rugby launched a second half fightback with two tries to secure a valuable win away from home for the Scots.
Thunder dominated the opening exchanges with some impressive phase-play before skipper Callender broke the visitors defence on the halfway line and raced away before slipping second row Shona Wakely the pass for the try.
The captain then set up the home side’s second try with another break from halfway and her grubber kick was snapped up by centre Ellie Tromans to score under the posts. Wing Amy Wiliams added the conversion to make it 12-0.
Edinburgh hit back with a try of their own by prop Panashe Muzambe, converted by full-back Nicole Marlow to haul the visitors back to within five points.
The visitors second try came after a quick tap-penalty saw scrum half Caity Mattinson level the scores 12-12 before wing Williams crossed in the corner to make it 17-12 to the home side at half-time.
After the break, Edinburgh tested the home side’s defence and Number 8 Freya Walker levelled the scores with a try in the corner before a solo effort by wing Cieron Bell secured the win.
Thunder captain Alex Callender makes a break
Gwalia Lightning lost their unbeaten record in the Celtic Challenge in heartbreaking fashion when the Clovers sealed a 19-17 victory with the last kick of the game in Cork.
Number 8 Gwennan Hopkins impressed again for the Welsh side and crossed for one of her side’s three tries, along with hooker Molly Reardon and replacement Tess Evans.
But a last ditch try by Clovers replacement Roisin Ormond levelled the scores at 17-17 before fly half Kate Flannery landed the conversion to seal the win.
The Lightning went into their first game on the road as Celtic Challenge leaders, but lost Wales fly half Robyn Wilkins ahead of the game due to illness.
Molly Anderson Thomas came in at No 10 and proved to be a threat for a Welsh side missing key players who had put them top of the table after two games.
The Welsh side were without Wales full back Nel Metcalfe and wing Catherine Richards who were both called up for English champions, Gloucester-Hartpury, and played in the win against Ealing Trailfinders on Saturday.
But the Lightning produced another impressive performance and were soon 10-0 ahead in the first half before the Irish side clawed themselves into a 10-12 lead at half-time.
Scrum half Sian Jones, who has impressed in every game for the Lightning in the tournament, converted Evans’ try to give the visitors a 17-12 lead before Ormond and Flannery clinched victory for the Clovers at the death.
