Rain and Snow from Cloud Seeding

Cloud seeding is done to increase precipitation in areas where extreme drought or long-term scarcity conditions exist.
Typical inorganic seeding nuclei

Cloud Seeding
Source - en.wikipedia.org

Most seeding procedures use inorganic particles or artificially produced organic particles.

AgI Molecule
Source- axcessbio.com 

Silver Iodide (AgI) is a commonly used inorganic condensation nuclei.
Dry Ice (solid Carbon dioxide) is another inorganic nuclei commonly used.
Artificial Precipitation Process

Precipitation Process
Source - en.wikipedia.org

For rain to fall upon demand i.e. for artificial cloud seeding to work, the air needs to contain super-cooled water. Super-cooled water is liquid water colder than zero degrees Celsius.
Silver Iodide has a crystalline structure very similar to that of ice and it is assumed that existence of this structure induces freezing temperatures that convert water vapor into super-cooled liquid water.
Dry ice achieves the super-cooling effect by its expansion that in turn super-cools water vapor.
Rainmaking using silver iodide or solid carbon dioxide both require existence of liquid droplets in super-cooled air.
These initially miniscule liquid droplets serve as the base for liquid and ice droplets to grow to a size large enough that they end up falling to the ground.
Cloud Seeding Goal
Lots and lots of rain is the goal of cloud seeding. Humanity cannot, however, capture much, if any, of this rain and, typically must wait for hydrological processes that add this artificially produced rainwater to existing reservoirs of liquid water that are water is being drawn water from.
Obviously, cloud seeding is an option for supplying multiple acre-feet of water rather than the few liters each individual requires.  

Defining the Challenge Differently

Sometimes a challenge is overcome simply when the problem is defined differently - usually from a different perspective. Ongoing Climate Change research may guide us to efficiently extracting moisture from the air we breathe.

Carbon Dioxide Emissions
Source - scinewsblog.blogspot.com

The Common Perspective on Climate Change - Cut Carbon Dioxide Emissions
To counter climate change, our overwhelming focus in every industry is on reducing addition of carbon dioxide into the atmosphere. 
This reduction is achieved by "scrubbing" emissions to capture the carbon dioxide they contain.
Typically, the "scrubber" chemically removes carbon dioxide in the emission. When the scrubber eventually  'wears out, it is replaced with a new scrubber. The 'used up' scrubber is disposed or cleaned up and reused.
The extracted carbon dioxide can be stored or the carbon can be processed to create artificial fuels that supplement fossil fuels.
What if we supplemented our focus on only emission reduction with extraction of carbon dioxide that we have added into air?
An Uncommon Perspective - Pull Carbon Dioxide OUT from Air 

Photosynthesis
Source - en.wikipedia.org

Source - guardian.co.uk

This perspective acknowledges that we have put carbon dioxide into the air and defines the climate change challenge as one of taking carbon dioxide out of air.
Photosynthesis is nature's technique for extracting carbon dioxide from the air - a technique that is impractical for use by people because of the lead time required to seed, nurture and grow the number of plants required to c lean-up today's air.
So we are left with developing artificial techniques for pulling carbon dioxide out of the air. Furthermore, these extraction techniques have a value all their own, even when we reduce the additions: We need them to extract the carbon dioxide that we have already added into the air. 
Three private companies seeking to develop a technically and economically viable process to take carbon dioxide out from air are Climeworks, Kilimanjaro Energy and Carbon Engineering.
Composition of Air
The air (in the troposphere) is composed of the following:

Nitrogen (N2)	78%
Oxygen (O2)	20%
Noble gasses	1%
Carbon dioxide (CO2)	0.03%
Water vapor (H2O)	0.97%

Source - http://www.lenntech.com
There is much much more water than carbon dioxide in the air!
Defining freshwater as a supply issue or a demand issue
So, how can we define the challenge of freshwater scarcity differently? One way is to see the glass half empty and reducing. Another way is to see the glass as half full and filling.
Extracting moisture from the air is an example of the latter approach. This approach has a lot in common with extracting nitrogen from the air to make artificial manure (fertilizer) responsible for feeding much of the world today. It also has a lot in common with extracting carbon dioxide from the air to curb climate change and its impacts.