That they found a way to win thanks to Tommy Seymour's late score - the only try of the game - was all the more commendable since they had lost Al Kellock, their inspirational captain, during the game's first quarter and were trailing with only 12 minutes remaining.
The lingering doubt over Glasgow at the end of last season had, after all, been whether they had sacrificed substance for style in running up lots of points but failing to improve on their previous season's Pro12 finish while going backwards in Europe, so these conditions provided an early test of resolve.
"I thought we played some good rugby in the first half but then seemed to lose our way a bit in the second when we didn't play the conditions as well," Gregor Townsend, their head coach, said afterwards.
"Going three points down when we did I thought it was going to be tough but it was a really well executed move by Tommy and I am delighted we managed to come back and win."
Whereas, at the end of this excellent Scottish summer, Glasgow might reasonably have expected a fine night for the fast-flowing play that generated much excitement at various stages last season, rain was teeming down as the game got under way.
They still got off to an encouraging start when Scott Wight registered the game's opening points from a penalty with only two minutes gone. However, an aerial examination was inevitable and Henry Pyrgos failed at the first time of asking from Tom Williams, the Blues full-back, his misfield almost resulting in a try as the ball fell loose just outside the 22 and Gavin Evans kicked it goalwards. A rebound off the post helped thwart the pursuing Williams, however, and Richie Vernon was first to it in goal.
The Blues maintained the pressure and Rhys Patchell levelled the scores then put his side ahead for the first time and when Wight then kicked the restart after the second of those direct into touch, it was clear this was not going to be as easy an assignment for Glasgow as it should have been.
Mark Bennett settled nerves soon afterwards, the gifted centre showing yet another dimension to his game in matching Patchell's second effort by sending a penalty over from halfway.
However, with the opening quarter still incomplete, the Warriors suffered a double blow as Byron McGuigan and, more worrying - not just because lengthy on-field treatment was required - Kellock were both forced from the field, the captain departing on a stretcher to warm applause.
In a messy half of rugby Glasgow spurned an excellent attacking opportunity after Sean Lamont had seized on the Blues' loss of possession at a lineout in the home team's half to power through the middle only for Wight, with considerable support alongside, to kick to touch.
They did, however, reclaim the lead and gain a numerical advantage in one fell swoop when Owen Williams was sin-binned for a late challenge on Peter Murchie and Wight duly kicked the resultant penalty.
The stand-off missed another chance soon after but on the stroke of half-time Bennett extended their advantage over the 14 men with a second long-range strike.
The quality of the weather did not improve after the interval and sadly neither did that of the rugby. It was consequently no surprise when the first points of the half came from the boot, Patchell this time reducing the leeway from wide on the left after a scrum collapsed just outside the 22.
Glasgow were repeatedly incurring the referee's wrath and, having pushed wide an attempt from inside his own half, Patchell found the target with his next from some 40 metres out.
The momentum was very much with Cardiff who were getting through the phases. Glasgow were doing most of their best work in defence while Cardiff were having the better of the kicking battle.
As another long-range penalty attempt by Bennett fell wide, the pressure was building and nervousness was working its way through the 5052-strong crowd, which intensified when Patchell dropped a goal from 30 metres to nudge his side ahead.
However, that mood changed to elated relief in an instant in the 68th minute as Tommy Seymour, who had replaced McGuigan, produced a magnificent solo score.
The situation looked less than promising when, from a lineout midway inside the Blues half, the ball was fed infield to the winger. He stepped off his right foot then veered right to leave two forwards grasping at air as he raced into the open and he had the pace to get to the right corner.
Ruaridh Jackson, who had replaced Wight, converted from close to the touchline and, confidence boosted, Seymour produced another searing break to put his side on the offensive again, ultimately resulting in a penalty under the posts which Jackson knocked over to make the cushion seven points.
When Cardiff were again reduced to 14 men when Macauley Cook was sin-binned it looked as if the job was done but the Welsh side somehow lifted themselves and with four minutes remaining scrum-half Lloyd Williams forced his way over the line only for the replay official to adjudge he had been held up.
Richie Vernon followed Cook into the sin bin as Cardiff were awarded a penalty for an infringement in the build-up to that effort. They opted to scrum, were awarded a penalty and chose to scrum again, only to blow their chance when they collapsed it this time around.