Structure and Formation Process of an Orographic Line-shaped Rainfall System during Baiu Season in Western Kyushu, Japan

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Structure and Formation Process ofan Orographic
Line-shaped Rainfall System during Baiu Season in
Western Kyushu, Japan

• Ayako Nakamura, Hiroshi Uyeda,
• (HyARC, Nagoya University, Nagoya, Japan)
• Osamu Morita,
• (Graduate School of Sciences, Kyushu University,
  Fukuoka, Japan)
• Yasufumi Kitazaki, Hideki Beppu
• (Fukuoka District Meteorological Observatory,
  JMA, Fukuoka, Japan)

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Three rainbands in Kyushu
Z2.0km
Max crest 461m
Sapporo
Max crest 569m
Japan
Kyushu
Max crest 511m
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Objective
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observation sites
Goto Islands
the Sefuriyama radar data
(the JMA operational radar)
Sapporo
upper-air soundings data
(at Fukuoka)
Japan
JMA wind profiler data
(at Hirado)
Kyushu
Meso Regional Analysis data
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Environmental field
Relative Humidity at surface
( by MANAL data)
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behavior and horizontal structure
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Vertical structure
Distance from Sefuriyama radar site km
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Wind profile and Froude number
19 JUNE 2001
09JST
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convective cells
Distance from Sefuriyama radar site km
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Summary
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Weather map at surface
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cloud image of GMS-5
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Comparison of other lines
(By Takeda et al. 1999)
(By Nakamura et al. 2002)
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Horizontal Feature
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Vertical Feature
1130
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Time variation
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Isahaya line
Takeda et al. 1999
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Koshikijima line
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Froude number
Froude number
By Smolarkiewicz and Rotunno(1989)
Small Fr(lt1)
horizontal detouring the obstacle
Large Fr(gt1)
the vertically propagating-wave pattern