The Extreme Forecast Index measures how far away from the model climate distribution the EPS forecast distribution is (the EPS Control is treated as a single member distribution). It scales from -1 (all members reach unprecedented small values) to +1 (all members reach unprecedented large values). See ECMWF Tech. Memo 373 (July 2002) or QJRMS, 2003 pp3037-3058 for more details (http://www.ecmwf.int/publications/library/ecpublications/_pdf/tm373.pdf). Compared to these last two references, it should be noted that a more selective definition (order=0 or Anderson-Darling metrics) has been introduced in line with the presentation given at the Users meeting in June 2003 (see "Product Development" Slides 4 to 11 at http://www.ecmwf.int/products/forecasts/d/inspect/catalog/publications/slides/mru/2003/ec/ProductDevelopmentFLalaurette!4/".

Parameters available in dissemination are listed in the Table 5.9.1.

Table 5.9.1 (ECMWF Local Code Table 2, parameter table, Version Number 132)

FIELD CODE	MARS ABBREV.	FIELD NAME	UNITS	NO. OF BITS/VAL.
165	10WSI	Ten metre wind speed index	-1 - 1	12
167	2TI	2 metre temperature index	-1 - 1	12
49	10FGI	Wind gust at 10 meters index	-1 - 1	12
228	TPI	Total precipitation index	-1 - 1	12

Time step range at which these parameters are made available differ for 00 UTC based and 12 UTC based products. For 00 UTC based products. See 5.9.1 bellow for more details. Please note that the STEP value in the form 'value1-value2' represents a product for a time range 'value1 to value2' and is made available in dissemination at 'value2' time step.

Horizontal resolution:

- 0.25 x 0.25 degrees latitude-longitude grid, or multiples thereof (leg 1)

- 0.5 x 0.5 degrees latitude-longitude grid, or multiples thereof (leg 2)

- the Gaussian grid appropriate to the forecast model in use. The following Gaussian grid numbers are supported: 320, 200, 160, 128, 80, 48 and 32.

- any sub-area

Extreme forecast index requirements

The following command language parameters are specific for the Extreme forecast index requirements. Other parameters are listed under the general EPS requirements above.

TYPE	=	EXTREME FORECAST INDEX EXTREME FORECAST INDEX CONTROL		[EFI] [EFIC]
DOMAIN	=	GLOBAL	[G]
NUMBER	=	OFF
PARAM	=	WIND GUST AT 10 METRES INDEX TOTAL PRECIPITATION INDEX 10 METRE WIND SPEED INDEX 2 METRE TEMPERATURE INDEX		[10FGI] [TPI] [10WSI] [2TI]
LEVTYPE	=	SURFACE	[SFC]
LEVELIST	=	OFF
GRID	=	* / AUTOMATIC [AUTO] If the form a/b is used, a latitude-longitude grid is defined, where: a= grid resolution (deg.) along a latitude line (i.e. East/West) b= grid resolution (deg.) along a longitude line (i.e. North/South) 0.25/0.25 or multiples thereof; (leg 1) 0.5/0.5 or multiples thereof; (leg 2) If a single positive integer is coded, it is interpreted as Gaussian grid number for grids defined as GAUSSIAN=REDUCED or REGULAR. The following Gaussian grid numbers are supported:320, 200, 160, 128, 80, 48 and 32. AUTOMATIC - values for the parameter GRID will be defined automatically based on STREAM/DOMAIN as well as RESOL/ GAUSSIAN parameter values;
STEP	=	* (hours)
		when TIME=00 12/36/60/84/108 12/36/60/84/108 24/24-48/48-72/72-96/96-120 6-30/30-54/54-78/78-102/102-126/6-126/ 30-150/240 when TIME=12 24/48/72/96/120 24/48/72/96/120 12-36/36-60/60-84/84-108/108-132 18-42/42-66/66-90/90-114/114-138/ 18-138/42-162		(PARAM=10WSI) (PARAM=2TI) (PARAM=10FGI) (PARAM=TPI) (PARAM=10WSI) (PARAM=2TI) (PARAM=10FGI) (PARAM=TPI)
		NB ALL is not permitted.

GRIB section 1 definition for Extreme forecast index data

'ECMWF local code table 2' version number used for EFI/EFIC products is 132.

Table 5.9.2 GRIB section 1 definition for EFI/EFIC products

Octet

Ksec1

element

Contents

ECMWF local GRIB use definition identifier.

19 = Extreme forecast index data

44-45

46-49

Class:

1 = Operations

Type:

27 = extreme forecast index

28 = extreme forecast index control

Stream:

1035 = Ensemble forecasts

Version number or experiment identifier.

(4 ASCII characters, right justified)

Zero, for compatibility with Mars labelling

Ensemble size

53-56

57-59

60-62

63-65

66-68

70-80

Power of 10 used to scale climate weight = F, say

Weight*10**F applied to climate month 1, stored as an integer

First month used to build climate month 1, YYYYMM

Last month used to build climate month 1, YYYYMM

First month used to build climate month 2, YYYYMM

Last month used to build climate month 2, YYYYMM

EFI order

Set to zero

18-01-2011