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The pre-convective environment: thermodynamic analysis by water vapour imagery channels 6.2 and 7.3 µm. Christo Georgiev NIMH , Bulgaria. Patrick Santurette Météo-France. EUMETSAT CWG Workshop, Landshut 8 – 10 October 200 9. WV IMAGERY DIAGNOSIS OF CONVECTIVE ENVIRONMENT.
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The pre-convective environment: thermodynamic analysis by water vapour imagery channels 6.2 and 7.3 µm Christo Georgiev NIMH, Bulgaria Patrick Santurette Météo-France EUMETSAT CWG Workshop, Landshut 8 – 10 October 2009
WV IMAGERY DIAGNOSIS OF CONVECTIVE ENVIRONMENT NWP 600 hPa winds 60 kt LOW-LEVEL FORCING: 7.3 m Convection is most likely to develop downstream (right) of a middle-level moisture boundary: a mid-level jet, which originates from a low-level baroclinic zone,Georgiev & Santurette ( 2008) (JET STREAM ANALYSIS PESPECTIVE) UPPR-LEVEL FORCING: 6.2 m Convection is most likely to develop downstream (left) of an upper-level moisture boundary: upper-level jet, left exit NWP 300 hPa winds 90 kt
MPEF DIVERGENCE PRODUCTfrom MSG 6.2 m Atm. Motion Vectors MPEF DIV, 300 hPa wind (> 80 kt) 1.5 PVU heights (> 1000 dam) convergence divergence upper-level jet PV anomaly WV IMAGERY 6.2 m as a diagnostic tool WV 6.2 m PV anomaly upper-level jet In addition to the stability analysis, a pre-convective environment should be analysed from a dynamic point of viewfor operational purposes. The instability and low-level pre-convective environment are critical for development of deep moist convection. Upper-level forcing mechanisms favor the convection outbreak and may enable further intensification of the convective development. WV imagery / products provide upper-level observation data for diagnoses of: Jet, Potential Vorticity anomaly, divergence of the flow.
MPEF DIV, 300 hPa wind (> 80 kt) 1.5 PVU heights (> 1000 dam) IR 10.8 MPEF DIVERGENCE (DIV) PRODUCTas a diagnostic tool MPEF DIV, 300 hPa wind (> 75 kt) 1.5 PVU heights (> 1000 dam) upper-level divergence upper-level jet upper-level jet PV anomaly PV anomaly upper-level diagnosis:divergent flow, ahead of a PV anomaly, left jet exit Convection initiates over a large area of instability at Southern Europe / Mediterranean. MPEF DIV product (derived from MSG channel 6.2 m Atmospheric Motion Vectors) helps to diagnose the area favourable for development of intense convection: Deep most convective cells develop at the area of upper-level divergence, ahead of a PV anomaly, at the left exit of an upper-level jet.