1. COSMO Priority Project ”Quantitative Precipitation Forecasts”
Work in Task 1, Langen 8 March 2006
Katarzyna Starosta,
Institute of Meteorology and Water Management, Poland

2. Used data and materials:
1. Bulletin of the national hydrological and meteorological service.
(monthly)
2.Every day meteorological bulletin.
3.Every day LM model results (numerical data and maps
with every 3 hour forecast, and cumulated precipitation
forecast from 3h to 78h)
4.Every day precipitation data from 308 rain gauges stations.
5.Interpolated (bilinear interpolation) data from the model
to rain gauges stations.
6.Results of monthly precipitation verification.
7.Difference between 24-precipitation sum in the rain gauges
stations and model results.

3. The results of verification of 24-h accumulated precipitation from January 2004 to December 2005 are presented below.
For precipitation we calculated indices from the contingency table for 24-h accumulated forecast data and data from 308 rain gauge stations for 3 day forecast range (1-day, 2-day, 3-day). For verification of precipitation thresholds 0.5, 1, 2.5, 5, 10, 20, 25, 30 mm were used.
For each threshold the following scores were calculated: FBI (Frequency bias index), POD (Probability of detection of event), PON (Probability of detection of non-event) FAR (False alarm rate), TSS (True skill statistics), HSS (Heidke skill score), ETS (Equitable skill score).
LOCATION OF RAIN GAUGE STATIONS 10 20 30 40 50 5 15 25 35 45

5. FREQUENCY BIAS INDEX, JANUARY - DECEMBER 2004
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
0.5 1
1.5 2
2.5 3
FBI
THRESHOLD 0.5 [mm] 4 5 6 7 8
I day
II day
THRESHOLD 10[mm]
III day
FBI
MONTHS

6. INDICES FOR 24h ACCUMULATED PRECIPITATION, JANUARY - DECEMBER 2004
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC 20 40 60 80
100 %
THRESHOLD 0.5 [ mm] 80
100 %
POD
PON
FAR
HSS
ETS
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC 20 40 60 %
MONTHS

7. INDICES FOR 24h ACCUMULATED PRECIPITATION, JANUARY - DECEMBER 2004
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC 20 40 60 80
100 %
THRESHOLD 10.0 [ mm]
I day 80
100 %
POD
PON
FAR
HSS
ETS
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC 20 40 60
II day %
III day
MONTHS

13. 2004 April 3 (for 6), 6,7,8 May 7,8 June 7(for 10), 19,20
July , 27-29
August ,13,14, 17,18(Szczecin) , 19-22
September ,15,16
October
November ,5, 18
December

14. 2005 January February 12,15 March 6,18 April 8,9,10, 20
May ,4, 18,19, (23)
June (8),9,10,15,16
July (Plock),9,10,26, 31
August ,4,7,8 15,16,23,24
September ,13,16,17
October
November
December ,7,15,16,20,30

15. 3 h 6 h 9 h 12 h Three forecast for the same day 23.08.05
Start of forecast: h h h
3 h
6 h
9 h
12 h

16. 15 h 18 h 21 h 24 h Three forecast for the same day 23.08.05
Start of forecast: h h h
15 h
18 h
21 h
24 h

17. 03 h 06 h Three forecast for the same day 24.08.05
Start of forecast: h h h
03 h
06 h