When do dust storms happen

In the past, motorists driving in dust storms have pulled off the roadway, leaving lights on. Vehicles approaching from the rear and using the advance car's lights as a guide have inadvertently left the roadway and in some instances collided with the parked vehicle.

Make sure all of your lights are off when you park off the roadway. Please Contact Us. Safety National Program. Dust Storms and Haboobs Weather. Wind Resources. In dry regions, the winds can pull dust from the ground up into the air, creating a dust storm. For example, dust storms are common in regions that are flat and have very few trees and plants.

These two features allow winds to build up momentum, causing the winds to grow stronger and drive more dust into the atmosphere. Although dust storms may end after just a few minutes, dust can hang in the air and cause problems for days or even months afterward. Dust storms — and their lingering effects — can be hazardous for several reasons:.

A dust storm approaching Stratford, Texas, in April Marsh Album. If a dust storm is spotted in your area, your local National Weather Service forecast office will issue a dust storm warning. Over the last decade, scientists have come to realize the impacts on climate, human health, the environment and many socio-econimic sectors. WMO Members are at the vanguard in evaluating these impacts and developing products to guide preparedness, adaptation and mitigation policies.

Sand and dust storms are common meteorological hazards in arid and semi-arid regions. They are usually caused by thunderstorms — or strong pressure gradients associated with cyclones — which increase wind speed over a wide area. These strong winds lift large amounts of sand and dust from bare, dry soils into the atmosphere, transporting them hundreds to thousands of kilometres away.

Comparatively, Australia, America and South Africa make minor, but still important, contributions. Global estimates of dust emissions, mainly derived from simulation models, vary between one and three Gigatons per year. Once released from the surface, dust particles are raised to higher levels of the troposphere by turbulent mixing and convective updrafts. They can then be transported by winds for lengths of time, depending on their size and meteorological conditions, before being pulled back down to the surface again.

As larger particles sediment more quickly than smaller ones, there is a shift toward smaller particle sizes during transport. Dust is also washed out of the atmosphere by precipitation. Aerosols, particularly mineral dusts, impact weather as well as global and regional climate. Dust particles, especially if coated by pollution, act as condensation nuclei for warm cloud formation and as efficient ice nuclei agents for cold cloud generation. The ability of dust particles to serve as such depends on their size, shape and composition, which in turn depend on the nature of parent soils, emissions and transport processes.

Dust particles also influence the growth of cloud droplets and ice crystals, thus affecting the amount and location of precipitation. Again, the ability of dust particles to absorb solar radiation depends on their size, shape and mineralogical and chemical composition.