the terrain

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

3-4 July 2007 missed heavy precipitation eventin the Western Swiss Alps(Or the art of forecasting precipitations in a mountainous region)

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

The terrain

Geneva

Zurich

Locarno

Bern

Lausanne

Basel

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

Heavy precipitation critical thresholds in Switzerland

50mm/24h

100mm/24h

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

• Unseasonably strong westerly flow across the Alps.• Passage of an active frontal system in this rapid flow• Unusually active warm front and warm sector• cold front starting to wave against the Alps• Mainly large scale precipitations certainly with a convective

component (but no thunderstorms)

What happened?

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

MeteoSwiss Surface analysis – 3 July 2007 12UTC

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

UK Met Office Surface analysis – 4 July 2007 00UTC

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

MeteoSwiss 500 hPa analysis – 3 July 2007 12UTC

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

Western Switzerland

WV 5.35 - 7.15 µm 3 July – 18UTC

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

WV 5.35 - 7.15 µm 4 July – 00UTC

Western Switzerland

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

ECMWF 01.07.2007 00UTC run – 24h precip for 3 and 4 July

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

ECMWF 01.07.2007 12UTC run – 24h precip for 3 and 4 July

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

ECMWF 02.07.2007 00UTC run – 24h precip for 3 and 4 July

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

ECMWF 02.07.2007 12UTC run – 24h precip for 3 and 4 July

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

Region receiving more than 50mm/12h

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

Hourly Precipitation rate in Aigle, le Bouveret and le Moléson

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

Consequences

• Floods• Landslides• Mudslides• Power outage• Fortunately no injuries or deaths!

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

A new tool – MAP D-PHASE

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Federal Department of Home Affairs FDHAFederal Office of Meteorology and Climatology MeteoSwiss

NWP Eumetcal course 26-29 November 2007 Langen – Germany Dean Gill

… and what about forecasting stratus cloud in mountainous regions?