POSTED: Thursday, April 24, 2014 - 10:49am
UPDATED: Monday, April 28, 2014 - 8:48am
Strong winds and blowing dust can be dangerous, damaging and unhealthy and can happen at other times of the year
Thursday, April 24th, 2014 — This “windy season" across the Borderland has not been too bad this year. We have seen about 4 or 5 really ugly dusty days caused by strong upper level weather systems and a couple cold fronts. Are we really in the final home stretch of the windy season? Yes, but that does not mean we will not see some blowing dust the rest of the year. In today’s “Weather Talk” I shall revisit what causes the strong winds and blowing dust, health and safety and damage concerns and why we could still see blowing dust after our windy season has ended.
Here in the Borderland we experience strong winds that produce large-scale dust storms that blow across southern New Mexico and western Texas especially during our “windy season”. The windy season usually starts late February and lasting through the spring months of March, April and typically winds down the beginning of May. These dust storms usually occur when winds gust over 50 mph blowing a dense tan or brownish clouds of dust and sand into the air. Visibility quickly goes down to less than a mile and less than 50 feet in some more vulnerable areas. The clouds of dust most times are lifted thousands of feet above the ground so that even the sun is obscured as the once blue sky turns a tan or an orange brown. Due to the low visibility and high winds, driving becomes very hazardous with collisions and multiple-vehicle pile-ups causing injury and even death across the region. In extreme cases, wind gusts exceeding 70 mph will damage roofs, buildings and overturn high profile vehicles.
Major wind and dust storms are the result of a meteorological disturbance or storm system known as the Lee Cyclone. The lee cyclone is actually a surface low-pressure system, which develops over the high plains just east of the Rocky Mountains. During the development of a lee cyclone, a strong trough of low pressure in the upper levels of the atmosphere or a surface cold front advances west to east across northern portions of Arizona and New Mexico or across Colorado. This storm track will induce strong west to southwesterly winds aloft to blow through the Borderland. While the upper trough or front travels eastward, the surface low intensifies in the vicinity of northeastern New Mexico, southeastern Colorado or the Texas panhandle. In the lower levels, increasing southwesterly flow transports warm dry air at the surface while the approach of the upper trough cools the air aloft, thus creating a dry but unstable atmosphere. These processes can generate windstorms because the strong upper level winds can mix downward, literally lifting the dust and sand at the ground thousands of feet upward. While lee cyclones are causing dust storms here in the borderlands, they are often associated with destructive weather further east. By pulling warm moist unstable air from the Gulf of Mexico northward, lee cyclones can generate severe thunderstorms, which produce hail, high winds, flash floods and even strong and violent tornadoes across northern Texas, Oklahoma and Kansas.
We do not see “haboobs” as often as say Phoenix or the deserts to our south, but we still do experience them here in the Borderland, especially during our “monsoon season”. Haboobs are sudden, sometimes massive dust storms. Haboob is pronounced “huh-boobs” and comes from the Arabic word haab, which means wind or blow. Haboobs are very strong dust and sand storms that move through hot and dry regions. Although they happen all across the desert southwest, these storms are not unique to America’s and Mexico’s Sonora Desert and Chihuahua Desert They are happen frequently regions such as the Sahara desert, the Arabian Peninsula, North Africa and the Gulf of Guinea. Haboobs are formed When air is forced down and pushed forward by the front of a traveling thunderstorm cell, it pushes and drags with it dust and debris. Winds of speeds of 60 to 80+mph will kick up dust and sand and create a blowing wall 10,000 feet or higher! Haboobs typically last only 10 to 30 minutes, but on rare occasions can last longer and create hazardous conditions for motorists and air traffic. These dry powerful thunderstorms hit Phoenix quite often during the monsoon season causing instant multi car pile ups. These types of dust storms are also possible during the late spring and summer months. When certain conditions exist, thunderstorms may occur which produce little rainfall but very strong winds during the warm season. Under these circumstances, dense blowing dust may develop over localized areas. They can still be dangerous however since dust storms induced by dry thunderstorms will happen very suddenly with little or no warning.
We all should listen to the latest weather forecasts and stay alert for the mention of high winds and dust storms. If strong winds and blowing dust and sand are forecasted, people traveling should be prepared for dangerous driving conditions due to very low visibility. Remember during strong winds, blowing dust and sand are especially severe along portions of Interstate 10 between El Paso and Las Cruces and also from near Deming west to Lordsburg. When visibilitiy becomes greatly reduced, persons should drive well below normal speed limits or even pull off to the side of the road and stop driving until conditions improve. People driving high profile vehicles like semi trucks, buses, recreational vehicles and even large pick up trucks should drive with care and even pull over. Strong wind gusts can easily cause these vehicles to flip or roll over.
Powerful 60 to 80+ mph wind gusts can tear our pieces of roofs, signs and other loose debris sending them dangerously hurtling through the air. Inspect your yard to make sure anything that can blow away is properly secured or stowed away. Inspect or have your roof inspected every couple years to make sure there are no loose tiles or damaged areas that could become airborne.
The blowing dust is also a health hazard, making breathing difficult for people with chronic lung ailments such as asthma or bronchitis. Individuals with breathing problems should spend little time as possible outdoors during a dust storm and should consider obtaining air-filtering devices for their homes.
Yes we are in the last few weeks of the windy season. The Borderland will still see some upper level waves, cold fronts or dying thunderstorms. There are a few “wind maker” systems that kick up a little desert dust in Autumn and Winter. Thankfully we do not have dust associated with every wind maker, especially if we have had a couple weeks where we have seen some rare desert rainfall. The dust storms are something we have to deal with, drive careful in, take some safety precautions and constantly clean up after. The strong ridge of high pressure that builds over the southwest in late May into June tends to steer the storm systems to our north. Then we all hope for a breeze to give us a little relief from our extreme summer heat.