# Presentation: 714151

## Requirements

## Products

**Constraints:**
**Not aiming at developing guides for forecasters. **
**Aiming at: public at large / specialized users.**
**Extend forecast period beyond 5 days:**
**Day 7 (10).**
**Product for week 2.**
**Scope :**
**Meteorological variables: **
**Precipitation. **
**Temperatures. **
**Winds. **
**Clouds (sky cover).**

## 1. Basic products

**On  each member :**
**Precipitation types (post-treatment).**
**Precipitation amounts stratified according to precipitation type.**
**Max/Min temperatures.**
**CAPE.**
**On the Ensemble :**
**Mean and variance of different parameters:**
**QPF**
**Mean sea level pressure**
**Relative humidity at 925, 850, 700 500 hPa**
**2m temperatures, 850 hPa**
**10 m winds**
**etc...**

## 2. Probabilistic products

**Over each 6-, 12- or 24-h periods between zero and 240 (360) hours. **
**Over several days between day 1 and day 10 (15) (1 to 5, 6 to 10, 11 to 15, 1 to 7, 8 to 14 and 1 to 15).**
**Probability of occurrence of different parameters:**
**Max/Min temperatures exceeding different thresholds (absolute or with respect to climatology). **
**Degree-Days (heating, growing etc.) exceeding different thresholds.**
**Wind speed exceeding different thresholds (absolute or with respect to climatology).  **
**Precipitation amounts exceeding different thresholds over 24-h periods (2, 5, 10, 25 mm).**
**Precipitation amounts exceeding different thresholds over 5 (7) days (25, 50 mm).**
**Five consecutive days without precipitation.**
**Temperature anomaly (3 equiprobable categories).**
**Precipitation anomaly (3 equiprobable categories).**

## 3. Public forecast products

**Text format :**
**Description in words of forecast weather.  **
**Day 1 to 3 :**
**In 12- (6-) h blocs.**
**Detailed terminology with single values for temperatures.**
**Days 4 to 7 (10) :**
**In 24-h blocs.**
**Simplified terminology with range of values for temperatures.**
**Text can be translated into graphics.**
**Challenge: how to express level of uncertainty ?**
**Table format:**
**Table of values for different parameters as function of probability thresholds.**

## Slide 6

## Slide 7

## Slide 8

## 4. Products for week 2 (days 8-14)

**Text and/or graphic format.**
**Two weather elements to consider: **
**Temperatures :**
**Range of values for Max/Min temperatures over days 8-14. **
**Description of tendencies if possible.**
**Temperature anomaly over days 8-14 (deterministic and/or probabilistic).**
**Precipitation :**
**Probability of precipitation amounts exceeding some thresholds over days 8-14.**
**Description of tendencies if possible.**
**Precipitation anomaly over days 8-14 (deterministic and/or probabilistic).**

## Slide 10

## 10 days: from 00 UTC 28 April to 00 UTC 8 May 2004

**10 days: from 00 UTC 28 April to 00 UTC 8 May 2004**

## Slide 12

## Slide 13

## Slide 14

## Slide 15

## Slide 16

## Slide 17

## Products

**Required :**
**Probability density function.**
**Probability estimation :**
**Counting members.**
**Calibration.**
**Parameterized technique.**
**Statistical Post-treatment (downscaling) :**
**Temperatures.**
**Probability of precipitation.**
**Bias correction of members.**
**Historical data:**
**Expected forecast skill.**