Use of Ensemble Forecast Robert Mureau KNMI Marco Nolet Reading 16 june 2005.

Use of Ensemble Forecast

Robert MureauKNMI

Marco Nolet

Reading 16 june 2005

Content Simple EPS verification First guess 5 day forecast New EPS plume product

Simple verification T2m (T00/T12) Ensemble mean Oper Forecaster

Winters 97-04

Summers 97-2003

T00 1997-2004 T+132

T12 1997-2004 T+144

T00 T+228

T12 T+240

Day 5 Tmin dec 1999- 2004

Day 5 Tmax Dec 1999-2004

Marco Nolet

Error Tmax De Bilt (day 1-5)

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Jan-

72

Jan-

73

Jan-

74

Jan-

75

Jan-

76

Jan-

77

Jan-

78

Jan-

79

Jan-

80

Jan-

81

Jan-

82

Jan-

83

Jan-

84

Jan-

85

Jan-

86

Jan-

87

Jan-

88

Jan-

89

Jan-

90

Jan-

91

Jan-

92

Jan-

93

Jan-

94

Jan-

95

Jan-

96

Jan-

97

Jan-

98

Jan-

99

Jan-

00

Jan-

01

Jan-

02

Bias

MAE1234

5

Climate

Climate

Tmax 1972-2002

Dag 5 Tmax: Overschrijdingen per maand

0

10

20

30

40

50

60

70

80

Jan-

81

Jan-

82

Jan-

83

Jan-

84

Jan-

85

Jan-

86

Jan-

87

Jan-

88

Jan-

89

Jan-

90

Jan-

91

Jan-

92

Jan-

93

Jan-

94

Jan-

95

Jan-

96

Jan-

97

Jan-

98

Jan-

99

Jan-

00

Jan-

01

Jan-

02

Pe

rce

nta

ge

>2

>2

>3

>4

>5

1981-2002

Dag 5 Tmin: Overschrijdingen per maand

0

10

20

30

40

50

60

70

80

Jan-

81

Jan-

82

Jan-

83

Jan-

84

Jan-

85

Jan-

86

Jan-

87

Jan-

88

Jan-

89

Jan-

90

Jan-

91

Jan-

92

Jan-

93

Jan-

94

Jan-

95

Jan-

96

Jan-

97

Jan-

98

Jan-

99

Jan-

00

Jan-

01

Jan-

02

Per

cen

tag

e

>2

>2

>3

>4

>5

Conclusions verification part No real trends in rms Bias control and ens mean are similar Gap opens at day 3 ? Ensemble mean best deterministic

value for money (but very safe)

First guess 5 day forecast

First Guess Table First guess 5 day forecast ( including

error margins ) Probabilities of events Special link with probabilities of severe

weather events

Table internet table

New EPS plot layout