Wilson Jones

ORIGINAL PAPER Origin of the pre-tropical storm Debby (2006) African easterly wave-mesoscale convective system

convective system (MCS) and African easterly wave (AEW) and their precursors were traced back to ... more convective system (MCS) and African easterly wave (AEW) and their precursors were traced back to the southwest Arabian Peninsula, Asir Mountains (AS), and Ethiopian Highlands (EH) in the vicinity of the ITCZ using satellite imagery, GFS analysis data and ARW model. The sources of the convective cloud clusters and vorticity per-turbations were attributed to the cyclonic convergence of northeasterly Shamal wind and the Somali jet, especially when the Mediterranean High shifted toward east and the Indian Ocean high strengthened and its associated Somali jet penetrated farther to the north. The cyclonic vorticity perturbations were strengthened by the vorticity stretching associated with convective cloud clusters in the genesis region—southwest Arabian Peninsula. A conceptual model was proposed to explain the genesis of convective cloud clusters and cyclonic vorticity perturbations preceding the pre-Debby (2006) AEW–MCS system. 1

African Easterly Wave-Mesoscale Convective System

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Climatology Study of African Easterly Wave and Mesoscale Convective System in Northern Africa

Moisture and Orographic Effects on the Evolution of African Easterly Waves and Mesoscale Convective Systems

Formation of AEWs and MCSs over Eastern Africa and its Implication to Tropical Cyclogenesis over Eastern Atlantic Ocean

The formation of African easterly waves (AEWs) and mesoscale convective systems (MCSs) in eastern... more The formation of African easterly waves (AEWs) and mesoscale convective systems (MCSs) in eastern North Africa and its impacts on the tropical cyclogenesis over the eastern Atlantic Ocean is studied. Based on numerical simulations using WRF model, the AEWs during the hurricane season may be generated by the orography and shear zone established by the Somali jet and anticyclonic circulation associated with the Asian monsoon to the north of the Ethiopian Highlands (EH) and Red Sea. The WRF is employed to simulate the pre-hurricane AEW-MCS system of Tropical Storm Debby (2006) near the EH. Finer-resolution numerical simulations demonstrate that the vortex generated on the lee and MCS over the mountain eventually merge and become an AEW-MCS system serving as a precursor of tropical cyclone. The larger-scale environments conducive to the formation of the AEW-MCS system are also investigated.

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Origin and a formation mechanism of pre-TC African easterly wave-mesoscale convective systems in eastern Africa

29th Conference on Hurricanes and Tropical …, 2010

... Based on the Meteosat-8 infrared imagery, we were able to trace the pre-Debby MCS back to Eth... more

Orographic and moisture effects on the evolution of the pre-Debby (2006) African easterly waves-mesoscale convective systems over Africa

Origin of the pre-tropical storm Debby (2006) African easterly wave-mesoscale convective system

Meteorology and Atmospheric Physics, 2013

Your article is protected by copyright and all rights are held exclusively by Springer-Verlag Wie... more Your article is protected by copyright and all rights are held exclusively by Springer-Verlag Wien. This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to selfarchive your work, please use the accepted author's version for posting to your own website or your institution's repository. You may further deposit the accepted author's version on a funder's repository at a funder's request, provided it is not made publicly available until 12 months after publication.

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Is Hyperplasia of Dendrocytes a Specific Feature of Histiocytoma cutis?

Dermatology, 1990

Steroid Atrophy – A Histological Appraisal

Dermatology, 1976

Epidermal Naevi

Dermatology, 1980

Atypical (annular) Necrobiosis Lipoidica of the Face and Scalp

Dermatology, 1967

12 Dowling, Wilson Jones, Atypical (annular) Necrobiosis Lipoidica The histopathology was distinc... more

Formation of African Easterly Waves and Mesoscale Convective Systems over Eastern Africa

Based on simulations of Tropical Storm Debby (2006) using the Weather Research and Forecast (WRF)... more Based on simulations of Tropical Storm Debby (2006) using the Weather Research and Forecast (WRF) model, the African Easterly Waves (AEWs) during the hurricane season may be generated by the orography and shear zone established by the Asian monsoon currents. The vortices often form on the lee of major mountain ranges. The MCSs are originated from the moist convection over the major mountain ranges as triggered by diurnal sensible heating. An MCS may merge with a vortex in the shear zone and form a coupled AEW-MCS system. The larger-scale environments conducive to the formation of the AEW-MCS system are also investigated, but using a much larger numerical model domain. This work is supported by a grant from the National Oceanic and Atmospheric Administration, Educational Partnership Program under the cooperative agreement NA06OAR4810187.

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Orographic Effects on the Evolution of African Easterly Wave-Mesoscale Convective Systems Across Africa

Effects of northern African mountains on the evolution of the Pre-Tropical Storm Debby (2006) Afr... more Effects of northern African mountains on the evolution of the Pre-Tropical Storm Debby (2006) African easterly wave-mesoscale convective system (AEW-MCS) are studied using a mesoscale numerical model. Specifically, we test the hypothesis, as proposed by previous studies, that moisture and vertical velocity played a major role in the generation and maintenance of the MCS convective cycles. With the mountains in central and western North Africa removed or the moisture reduced, we found that the embedded MCS is weakened and the convective cycles less apparent. Effects of PBL are also found to play a major role in modulating the AEW-MCS system. Both orographic and PBL effects are essential in the proper development and propagation of the AEW and its subsequent disturbances. This work is mainly supported by UCAR SOARS Program and partially supported by a grant from the National Oceanic and Atmospheric Administration, Educational Partnership Program under the cooperative agreement NA06OAR4810187.

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Orographic Effects on the Evolution of AEW-MCSs Across Northern Africa

The pre-development period of Tropical Storm Debby (2006) initially formed over the Ethiopian Hig... more The pre-development period of Tropical Storm Debby (2006) initially formed over the Ethiopian Highlands (EH) region is studied in conjunction with the African easterly wave (AEW) disturbance and the embedded mesoscale convective systems (MCS). Based on infrared satellite imagery and numerically simulated results, several convective genesis and lysis periods are identified. With the mountains in central and western North Africa replaced by flat terrains, we found that the embedded MCS is weakened and the convective cycles less apparent. Similar effects are found with the reduced moisture content. It is found that the PBL effects and moisture availability are important for maintaining AEW-MCS system as it travels to the west and supporting sufficient moisture by allowing for surface moisture fluxes to affect these systems and aid in convective development. The AEW is slightly modulated by orography downstream from the EH region. Both the EH region and the PBL effects are essential in the proper development and propagation of the AEW and its subsequent disturbances.

Formation of AEWs and MCSs over Eastern Africa and its Implication to Tropical Cyclogenesis over Eastern Atlantic Ocean

by Guoqing Tang, James Spinks, and Wilson Jones

The formation of African easterly waves (AEWs) and mesoscale convective systems (MCSs) in eastern... more The formation of African easterly waves (AEWs) and mesoscale convective systems (MCSs) in eastern North Africa and its impacts on the tropical cyclogenesis over the eastern Atlantic Ocean is studied. Based on numerical simulations using WRF model, the AEWs during the hurricane season may be generated by the orography and shear zone established by the Somali jet and anticyclonic circulation associated with the Asian monsoon to the north of the Ethiopian Highlands (EH) and Red Sea. The WRF is employed to simulate the pre-hurricane AEW-MCS system of Tropical Storm Debby (2006) near the EH. Finer-resolution numerical simulations demonstrate that the vortex generated on the lee and MCS over the mountain eventually merge and become an AEW-MCS system serving as a precursor of tropical cyclone. The larger-scale environments conducive to the formation of the AEW-MCS system are also investigated.

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