The most common and most likely answer to this crossword clue is the 9 letter word WHITE-OUT
I've seen this crossword clue in The Guardian
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More clues leading to the result WHITE-OUT
Buddy explains!
The straight part
We know that "heavy blizzard" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case heavy blizzard = white-out.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does WHITE-OUT mean?
WHITE-OUT noun- A heavy snowstorm; a blizzard.
- Any weather condition in which visibility and contrast are severely reduced by snow or sand causing the horizon and physical features of the terrain to disappear.
- Correction fluid (from the brand name Wite-Out).
- A sporting event where all in attendance are urged to wear white apparel.
- The simulated erasure of a file, etc. on a read-only volume.
- The suppression of a story by the media, analogously to deleting information with correction fluid.
- The silencing of voices and perspectives other than those of white men.