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Italian Meteorological Service (UGM / CNMCA). A deterministic post-processing program for an A utomatic W eather I nterpretation. Fabrizio Ciciulla. Contents. Introduction Architecture of AWI program Case studies Planned developments. Introduction.
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Italian Meteorological Service (UGM / CNMCA) A deterministic post-processing program for anAutomaticWeatherInterpretation Fabrizio Ciciulla
Contents • Introduction • Architecture of AWI program • Case studies • Planned developments
For an operational forecaster it’s important to rely on automatic technical procedures in the numerical model output fields analysis and interpretation. Such a guidance tool will describe the numerical model output in a synoptical way and will suggest the possibility of occurence for weather events like fog, drizzle, showers or thunderstorms.
At this end the Italian Air Force Meteorological Service is renewing its post-processing operating procedures realizing such an objective and automatic interpretation of numerical model output fields by means of a program called AWI (Automatic Weather Interpretation). The original idea for such a program derives from the automatic weather interpretation scheme developed by DWD.
Architecture of the AWI program
Design choices • Use of standard format for I/O (in order to let a possible exchange of the product) • GRIB (input) (LAMI, italian version od LM, produced by CINECA with BC from GME) • BUFR (output) (as a forecast pseudo-synops dataset) • Use of a scheme adapted to WMO regulations • Weather phenomena distinguished : • Fog (with and without rime ice) • Drizzle (also freezing) • Rain-fall (slight, moderate, heavy / freezing) • Snow-fall (slight, moderate, heavy) • Snow-showers (slight, moderate to heavy, violent) • Rain-showers (slight, moderate to heavy, violent) • Thunderstorm and heavy thunderstorm
ENCOD DECOD GRIB (DATASET) BUFR (DATASET) AWI Plotting routines maps
ELAB O CONTROL OUTPUT FILE ARRAY SCANNING BUFR ARRAY loading GRID-POINT FUNCTION WW ARRAY Calculation of the PRECIP RATE AWI I GRIB reading
Input Data T (2 mt) 10 mt windspeed CLDs coverage RH LS RAIN (mm/h) LS SNOW (mm/h) C-LWC Base of the CC Top of the CC Soil T Grid-point Function Surface P Td (2 mt) OROG LSM T (pl) T (ml) P (ml) K RAIN (mm/h) K SNOW (mm/h) FOG DZ RA SHRA SHSN SN TS WW
A C Total precipitation < an assigned threshold ( 0.015 mm/h ) Height < 300 mt B F T2m OR Tsoil < -1 °C T2m – TD2m < ΔT (it depends on the Tsoil value) D E 10m windspeed < a max assigned threshold 10m windspeed > a min assigned threshold Phenomena { } WW = 48 WW = 45 = IF A and B and C and D 1 { } = IF 2 1 and E and F FOG Conditions
A C Total precipitation > an assigned threshold ( 0.015 mm/h ) B ( LS precipitation > Convective precipitation ) OR (MC coverage > 95 %) T2m < a max assigned threshold (1 °C) D1 (LP > 0) and (0.25 LP <= SP < 0.75 LP) D E T2m < a min assigned threshold (-10 °C) IF Solid Precip > 0 D2 ((LP > 0) and (SP >= 0.75 LP)) or (LP = 0) F Supplementary Condition for liquid Preciopitation not verified D3 (LP > 0) and (SP < 0.25 LP) ( TP <= 0.25 mm/h ) G1 G Precipitation-rate threshold ( TP > 0.25 mm/h ) and ( TP <= 2 mm/h ) G2 ( TP > 2 mm/h ) G3 ( TP <= 2 mm/h ) G4 SNOW - 1 Conditions
Condition { IF G4 { } and ( or ) IF 1 D1 F ELSE { IF G1 IF G2 IF G3 { } { } = and ( or or ) IF 1 E F D2 1 and and and ( NOT ) A D3 B C WW = 68 WW = 70 WW = 73 WW = 75 WW = 69 SNOW - 2 Phenomena
A C Total precipitation > an assigned threshold ( 0.2 mm/h ) TTI > 40 B Pbase_CC – Ptop_CC > 400 hPa { { CP > 0.5 mm/h CP > 2 mm/h IF IF Phenomena - 4 <= KOI < 2 KOI < - 4 { } IF A and B and C WW = 95 WW = 96 THUNDERSTORM Conditions
Case 1 11 – 12 March 2003
METAR of 12 - 03 - 2003, 07.00 UTC LIMS 120655Z 22002KT 2800 BR NSC 06/05 Q1021 RMK BKN FEW120 BKN200 YLO LIMN 120655Z 01001KT 0500 FG NSC 03/02 Q1020 RMK FEW FEW200 RED LIMC 120650Z 00000KT 0900 R35R/1500N R35L/1500N BCFG RED LIME 120650Z VRB01KT 1500 BR SCT015 BKN020 09/07 Q1021 LIPL 120655Z 29009KT 2800 BR FEW040 SCT200 11/09 Q1021 RMK BKN YLO LIPX 120655Z 03001KT 0800 R05/P1500 FG FEW005 SCT100 06/05 Q1021 RMK BKN AMB LIPT 120655Z 00000KT 0000 FG VV001 06/05 Q1021 RMK RED LIPS 120655Z 07003KT 0000 FG VV001 07/06 Q1021 RMK RED LIPH 120655Z 09002KT 0050 R07/0175 FG VV001 08/07 Q1021 RMK WIND THR07 09002KT RED LIPZ 120650Z 00000KT 0100 R04/0250N FG VV001 08/07 Q1020 LIPI 120655Z 02002KT 1500 BR SCT030 SCT070 08/07 Q1021 RMK BKN AMB