The phrase "almost as abruptly" is correct and usable in written English.
It can be used to describe an action or event that occurs suddenly or unexpectedly, but not quite as sudden as something else.
Example: "The meeting ended almost as abruptly as it had started, leaving everyone confused."
Alternatives: "nearly as suddenly" or "practically as unexpectedly".
Then they'd dropped again, almost as abruptly.
Almost as abruptly, he changed his mind in March 1999.
Then, almost as abruptly as it began, the video was over.
The waters that surged through the village of Louzishui on the outskirts of Beijing fell almost as abruptly as they had arrived.
The rioters' targets included a courthouse, police stations and trade union offices.In this section The struggle for the soul of a country Waking up too The president may think he can win Angry young men Something very rotten Cementing a fortune ReprintsThe sound and fury on the streets ended almost as abruptly as it had begun.
But the more casual reader will be less interested in plowing through a dozen pages on the debacle that was "In the Boom Boom Room," the Rabe play that inaugurated Papp's turbulent tenure uptown when he expanded his fief to include the theaters at Lincoln Center, a project he abandoned almost as abruptly as he'd undertaken it.
Lee signals this by abruptly ending the segment, almost as if he were lifting a needle off a record, and then switching to the more grounded sound of Terence Blanchard's elegiac trumpeting.
Shields had her hand over her heart on the medal podium when she abruptly burst into laughter, her head snapping back almost as if she had just been punched in the face.
She and the other L-dopa patients in the 1973 documentary seem very far away from us now -- almost as far as they were from their 1920's pasts, their abruptly severed pre-encephalitic lives.
She abruptly stopped kissing her daughter good night at the age of 7, which felt, the author says, "almost as if she'd slapped me".
Then, just as abruptly, her fierceness subsides.
