2024-2 Numerical Weather Prediction
SUPERCELL
Intensity
As the size of the supercell increases, the intensity of atmospheric dynamics also increases, leading to stronger updrafts, downdrafts, and enhanced horizontal shear. This is evidenced by higher vertical velocity (W), more pronounced core updrafts in the YZ cross-section, and stronger horizontal shear around updraft regions in larger supercells.
Vertical velocity(W)
Overview
The vertical velocity (W) component is essential for understanding the intensity of updrafts within supercells. Strong updrafts indicate higher potential for severe weather conditions, due to the rising motion of air parcels within the supercell.
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Higher W values: signify stronger updrafts, leading to intense convective activity
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Updraft regions: Central areas of supercells exhibit strong W values
Analysis
Initial Updraft Intensity
In the early stages of supercell development, strong updrafts are observed due to mesocyclone formation, particularly in larger supercells.
Supercell Size Comparison
As supercell size increases, the strength and vertical reach of updrafts also expand, confirming enhanced convective potential.
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5km: Exhibits relatively low peak values for WWW, with limited vertical spread of updrafts.
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10km: Shows an increase in updraft intensity and an expansion in the vertical extent of the flow.
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30km: Displays the highest vertical velocity values and a broader vertical distribution of updrafts.
Conclusion
Larger supercells exhibit stronger vertical velocity (W) values that extend over a broader vertical range. This suggests that larger supercells are more likely to produce intense and concentrated rainfall due to their powerful updrafts, impacting precipitation patterns more significantly.
W Cross-Section in the YZ Plane
Overview
The W cross section in the YZ plane provides a detailed view of the vertical wind component within the supercell structure. his analysis reveals a typical supercell structure, with a strong central updraft flanked by downdrafts on both sides.
Analysis
Core Updraft Intensity
The analysis focuses on the central updraft, where larger supercells exhibit significantly stronger vertical velocities. This intensified core updraft is characteristic of a typical supercell structure, providing the conditions for sustained and intensified convective activity.
Flanking Downdrafts
Downdrafts flanking both sides of the central updraft are more prominent in larger supercells. This configuration enhances the intensity of the updraft within the core by directing surrounding airflow effectively.
Supercell Size Comparison
As supercell size grows, the updraft structure becomes more robust and reaches higher altitudes.
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5km: Small initial size results in relatively weak core updraft intensity and limited vertical development
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10km: Shows moderate core updraft intensity
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30km: arge initial size demonstrates a strong core updraft
Conclusion
The W cross section in the YZ plane illustrates that larger supercells feature stronger core updrafts flanked by downdrafts on both sides, forming a typical supercell structure. This internal configuration amplifies the supercell's intensity, indicating that supercell size has a significant impact on its vertical wind dynamics.
Horizontal Wind Shear (1000-925hPa)
Overview
Horizontal wind shear in the lower atmosphere is essential for understanding rotational dynamics in supercells. Stronger shear enhances rotational potential, which contributes to the intensity of convective activity in supercells.
Analysis
Horizontal Wind Shear Visualization
Contour plots illustrate shear intensity around the updraft regions, revealing differences across supercells of varying sizes.
Supercell Size Comparison
Larger supercells exhibit more intense shear around updraft regions compared to smaller ones, indicating that supercell size has a direct impact on rotational strength and convective intensity.
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5km: Minimal shear observed, resulting in limited rotation potential.
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10km: Moderate shear develops, contributing to some rotational organization.
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30km: The strongest shear observed, maximizing rotational strength around the updraft.
Conclusion
Horizontal wind shear intensifies with increasing supercell size, particularly around the updraft regions, leading to enhanced rotational potential. This trend indicates that larger supercells have greater rotational dynamics, contributing to their overall intensity.