Winds were generally mid Channel but hit 80 mph overnight at St Helier harbour.
Jersey Met senior forecaster Rob Plummer says the rainfall brought by Storm Benjamin was exceptional.
For the period between 3pm on Wednesday (22) and 8.30am today (23) the dry islands' period ended in a dramatic fashion:
"If we add it all up, it was a huge total for Jersey at 27.2mm but quite frankly colossal for Guernsey at 57mm."
This is more than 2 inches.
Mr Plummer says the French Met named the storm because of its track.
Wind speeds were higher mid Channel, although overnight gusts were strong:
"Around 3am quite a few people may have been woken up, I know I was.
"That's when Guernsey had the strongest gusts (at the airport) of 56mph.
"At pretty much the same time it was 70mph recorded at Jersey Airport and 80mph at the harbour."
Rob says the storm has now tracked north eastwards, and what we are left with is more classic, windy autumn weather.
But he says the next day or so will be blustery, with gusts up to 50mph in any squalls this afternoon.


Guernsey businesses encouraged to use the daily St Malo ferry for European imports
Guernsey's airline to drop its European holiday routes
A total ban on disposable vapes in Guernsey and Jersey is poised to take full effect
Guernsey's Air Display to remain an early evening event
Disgraced Guernsey politician and pastor jailed for 9 years
10,000 LEGO brinks needed to build memorial bench for Guernsey boy
Former Island FM and Guernsey radio star dies
Storm Ingrid halts Guernsey charity sleep-out