The phrase "a rapid sudden" is not correct and is redundant in written English.
You can use it when describing something that occurs quickly and unexpectedly, but it would be better to choose one of the adjectives.
Example: "The storm brought a rapid sudden change in weather, catching everyone off guard."
Alternatives: "a swift change" or "a quick shift."
The Joint Forces Command recently issued a study saying that Mexico — along with Pakistan — could be in danger of a rapid and sudden collapse.
The Joint Forces Command has compared Mexico to Pakistan, arguing that both may be on the verge of a "rapid and sudden collapse" [pdf].
It is the state the US Joint Chiefs of Staff say is most likely, after Pakistan, to suffer "a rapid and sudden collapse". Why?
Which country was just named by the US Joint Chiefs of Staff as the most likely after Pakistan to suffer a "rapid and sudden collapse"?
Last November the Pentagon's Joint Forces Command concluded that Mexico was at risk of a "rapid and sudden collapse" due in part to "sustained assault and pressure by criminal gangs".
Since we cannot differentiate ALA from He-ALA with our method of determination, we cannot determine if He-ALA leads to a rapid and sudden death at high concentrations due to a toxicity induced per se or if it is rapidly cleaved by brain esterases to release ALA and hexanol, both of them very harmful compounds at high concentrations.
First, such processes and events lay the foundations from which rapid, sudden onset disasters emerge.
To date, hazard and disaster scholarship has been preoccupied mostly with the flare and glamour of rapid, sudden onset events.
The reactor showed a high stability and a rapid response to sudden changes in the COD influent concentration.
But recurring segments weren't the focus, each show instead remaining consistently unpredictable and juggling a rapid pace with sudden leaps in tone.
