It looks like January will be going into the books as tied for the 7th driest on record…not catastrophic in itself, but bad timing in light of our drought. Partly cloudy to mostly sunny conditions will continue through the weekend before another weak and warm low pressure system similar to the last one comes up from the south giving us a slight chance of a few light rain showers on Monday.

Most clouds contain supercooled water droplets.

Most clouds contain supercooled water droplets.

Before talking about what is needed before cloud seeding does one any good, let’s look at what cloud seeding does. Simply, in order for rain or snow to fall, you need a cloud, and in order for a cloud to form, you need the air to be saturated (100% humidity.) Once clouds form, they are often made up of microscopic supercooled water droplets (yes, you can cool water down below 32 degrees without it turning immediately to ice.) A supercooled water droplet will turn to an ice crystal if it has a nucleation site, such as a particle of dust. Once the ice starts to form on the nucleation site, it quickly grows and eventually becomes a snowflake (or raindrop if it melts on the way down.) Tomorrow, how we can help that process along.

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