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Algerian low / moist LLJ
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LOW LEVELS
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Cold-core cut-off low / ULJ
Baroclinicity / moist LLJ
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UPWARD QUASIGEOSTROPHIC FORCING 500 hPa
MID- UPPER LEVELS
LOW LEVELS
7286
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pattern
Cold-core cut-off low / ULJ
Baroclinicity / moist LLJ
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- *$1',$: 36 h, from 00 UTC 3 Nov. 1987
- 7286: 24 h, from 00 UTC 20 Oct. 1982
3K\VLFDOSDUDPHWHUL]DWLRQV
- 3%/: Based on Blackadar (1979) scheme (Zhang and Anthes 1982)
- *URXQGWHPSHUDWXUH: Force-restore slab model (Blackadar 1979)
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Location / Stationarity: well
QPF: underestimated
Algerian low / Mesolow
Convergence ahead of LLJ
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PRECIPITATION
LOW-LEVEL CIRCULATION
PRECIPITATION
LOW-LEVEL CIRCULATION
7286
Location / Stationarity: well
QPF: underestimated
Westward-moving low / ULJ
Embedded mesolow
Convergence over SE Spain
7286
Location / Stationarity: well
QPF: underestimated
Westward-moving low / ULJ
Embedded mesolow
Convergence over SE Spain
11
PRECIPITATION
LOW-LEVEL CIRCULATION
7286
Location / Stationarity: well
QPF: underestimated
Westward-moving low / ULJ
Embedded mesolow
Convergence over SE Spain
*$1',$
Strong WV flux convergence
Boundary of instability
E-W elongated moist tongue
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WV FLUX CONV. / CONVECT. INST. / PW
FRONTOGENESIS / UPWARD MOTION
7286
Strong WV flux convergence
Convective instability
High values of PW
Frontogenetic action
Upward motion in response
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*$1',$
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Coastal plume of moist, ascending air
Precipitation efficiency / Mesolow
Explicit convection
Local orography
60% precipitation
MODEL SOUNDING AT S
W-E CROSS SECTION
(CIRCULATION / RELATIVE HUMIDITY)
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7286
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Deep plume of moist, ascending air / Dynamic forcing
Precipitation efficiency / Mesolow
Explicit convection
Local orography
30% precipitation
MODEL SOUNDING AT S
W-E CROSS SECTION
(CIRCULATION / RELATIVE HUMIDITY)
13
*$1',$
Rainfall suppression
No inland peak
SLP appreciably modified
Less convergence / Shift LLJ
12$7/$6
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PRECIPITATION
LOW-LEVEL CIRCULATION
PRECIPITATION
LOW-LEVEL CIRCULATION
FULL SIMULATION
FULL SIMULATION
7286
Rainfall suppression
No inland structure
SLP appreciably modified
Shift Low / LLJ
Weak convergence SE Spain
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Extensive pressure decrease over the Mediterranean
Cyclogenesis / Enhancement of easterlies and convergence
Southward shift of the rainfall activity
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SLP / 925 hPa WIND FIELD / PRECIPITATION
7286
Pressure decrease limited to the east of the Balearics
Northerly winds and offshore outflows over eastern Spain
General rainfall suppression
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Mesolow over eastern Spain
Intense mesoscale cyclonic circulation / strong convergence
Focusing of rainfall over central Valencia
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Mesolow over southeastern Spain
Intense vortex / strong convergence line
Substantial rainfall enhancement (elongated structure)
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Complex pattern in space and time
Southward shift of the rainfall activity
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Complex pattern in space and time
General rainfall suppression over land
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