what causes torrential drizzle

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jamie
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what causes torrential drizzle

Unread post by jamie »

I have always wondered what causes torrential drizzle.

Today was a classic example of it. I had to have wipers on full speed because the drizzle was so thick and heavy.

Interestingly, at that time, there were sporadic drops of normal-large rain drops falling.

I suppose I'm keen to know what was going on upstairs to have torrential drizzle yet sporadic normal drops.
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Dale
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Re: what causes torrential drizzle

Unread post by Dale »

Could ask the same here, was in town earlier this morning & came upon some torrential rain, but the hail I didn't expect!
Nor the backshearing anvils this afternoon.

Torrential drizzle.. I like it!
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Tornado Tim
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Re: what causes torrential drizzle

Unread post by Tornado Tim »

Yes today this morning there was a good case of this "torrential drizzle". I have a suspicion it has something to do with the upper level dynamics such as updrafts, relative humidity and moisture content both at the surface and in the upper atmosphere.

More vigorous updrafts hold and retain more water vapour, also they are well defined, it would somehow be along the lines of how these updrafts and gravity effects have an effect on the breaking up on the water droplets.
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tgsnoopy
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Re: what causes torrential drizzle

Unread post by tgsnoopy »

Hate torrential drizzle, you think it's only light stuff, but it soaks you to the skin in no time at all. Seems to occur more on high humidity days from what I recall.
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NZstorm
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Re: what causes torrential drizzle

Unread post by NZstorm »

The best examples of drizzle occur in the South Island I think. Dunedin and Christchurch get classic drizzle when they get a stable moist onshore flow. Technically drizzle falls out of stratus.
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