As we transition to summer, our meteorologists prepare to forecast longer duration Shamal events. Shamal winds are strong winds that blow from the north to northwest over the arid Middle East. In winter, Shamals are associated with the passage of cold fronts. Cold fronts still influence the region’s weather through May, but by summer the region warms significantly and fronts become less frequent. Shamals from fall through spring are typically short-lived, lasting one to two days. By June, nearly stationary thermal lows along the monsoon trough over Northwest India, Pakistan and Southeast Iran interact with high pressure over the eastern Mediterranean and Saudi Arabia to produce more persistent northwesterly winds over the Arabian/Persian Gulf. Winds strengthen between these seasonal highs and lows as the low pressure areas intensify during summer months. Rao et al. (2003) found that gale force winds and rough seas offshore Qatar are more common in June than May and July.
Shamal winds are strongest during the afternoon when hot surface air rises, creating turbulent eddies that mix winds higher in the atmosphere to the surface. High temperatures, strong winds and the seasonal lack of precipitation all contribute to the formation of blowing dust during these events. Sand and dust may be carried hundreds of kilometers across the Gulf states in dust storms, producing areas of near zero visibility.
Offshore operations and marine transits in this region may be suspended due to common effects from a Shamal:
- Persistent strong to gale force winds.
- Rough to very rough seas.
- Low visibility in blowing dust and sand.
To improve summer planning, our meteorologists incorporate advanced, high-resolution dust and sandstorm forecast data into daily weather reports and visibility outlooks for its customers. The data is sourced and exclusively licensed from the Barcelona Supercomputing Centre (BSC), host of the World Meteorological Organization’s Sand and Dust Storm Warning Advisory and Assessment System for the EuMEA region.
“Through our exclusive license and partnership with BSC, we have customized the output from the forecast model to provide our clients in both the marine and aviation sectors, a detailed projection of the site-specific impact of blowing dust and sandstorm events across Africa and the Middle East,” said Ryan Fulton, Sr. Program Manager for WWT. “It has also allowed us to provide dust-impact operability assessments based on historical data for clients operating in these regions.”