The phrase "a warning recommending" is correct and usable in written English.
It can be used when you want to convey a cautionary message that also suggests a course of action or advice.
Example: "The report included a warning recommending that all employees undergo safety training to prevent accidents."
Alternatives: "a caution suggesting" or "an alert advising".
But the agency has issued a blanket warning, recommending that consumers throw out all prepackaged fresh spinach rather than cooking it because of the chance of cross-contamination.
In 2005, after the identification of cardiovascular safety concerns with the use of nonsteroidal anti-inflammatory drugs (NSAIDs), the FDA issued a black box warning recommending against the use of NSAIDs following cardiac surgery.
The results of the two earlier trials prompted the US Food and Drug Administration FDAA) to issue a black box warning for all ESAs in March of 2007; the warning recommended that ESAs be used at the lowest level necessary to prevent RBC transfusions [ 12].
That warning recommended that people limit their consumption of swordfish, shark, tilefish and king mackerel.
The travel warning recommends that pregnant women, women of reproductive age and their partners get tested for Zika if they were in Brownsville on or after Oct. 29.
The FDA's black box warning recommends that physicians should observe for "clinical worsening, suicidality, and unusual changes in behavior" during these initial visits or "at times of dose changes, either increases or decreases".
12 The warning recommended families and caregivers to closely monitor patients with ADHD not only for suicidal ideation but also for suicidal behaviour, especially during the initial stage of treatment or at times of changing doses.
The department issued a warning this month recommending the standard meningitis vaccination for a particular subset of the population: "men, regardless of H.I.V. status, who regularly have intimate contact with other men through a Web site, digital application or at a bar or party".
Since on the basis of a large number of other signs we can be fairly sure that the shape and color pattern of these two signs indicates nothing beyond the fact that the first is a regulatory sign prohibiting something and the second is a warning sign recommending something, there is a problem for compositionality here.
She also has the ability to write hooks so sweet they should come with a warning about the recommended daily intake of sugar and girl gang choruses so catchy she describes them as "borderline annoying".
