1. Weather Dependent Verification and link with forecasters
Flora Gofa
WG5 COSMO General Meeting, Moscow 2010

2. Objective Is this feasible???
The aim is to provide more useful guidelines to forecasters regarding the use of NWP products.
An effort is made to extract information concerning the performance of the model in specific weather patterns.
Is this feasible???
COSMO General Meeting, Moscow 2010

3. Weather Classification
Several discussions concerning the best way to classify weather patterns; a subjective approach is always applied.
The selected method is based on a synoptic classification scheme (Mahairas at al, 1982, 1988, 1989) with amendments based on feedback from forecasters in relation to the weather associated with each of the categories.
The final classification scheme consists of 12 categories.
WG5 COSMO General Meeting, Moscow 2010

4. 1. Zonal cyclonic
4. N-NW anticyclonic
7. S-SW cyclonic
6. N-NE anticyclonic
S-SE cyclonic
10. S-SE anticyclonic
12. Stationary anticyclone
1. Zonal cyclonic
5. N-NE cyclonic
4. N-NW anticyclonic
11. Cut-off
8. S-SW cyclonic
7. S-SW cyclonic
WAM
3. N-NW cyclonic
2. Zonal anticyclonic
2. Zonal anticyclonic
5. N-NE cyclonic
8. S-SW cyclonic
S-SE cyclonic
10. S-SE anticyclonic
12. Stationary anticyc
3. N-NW cyclonic
6. N-NE anticyclonic
11. Cut-off 11
WG5 COSMO General Meeting, Moscow 2010

5. Stationary Anticyclone
January – July 2010
Type Num
Weather Type
Number Days 1
Zonal cyclonic 59 2
Zonal anticyclonic 30 3
N-NW cyclonic 33 4
N-NW anticyclonic 5
N-NE cyclonic 6
N-NE anticyclonic 7
S-SW cyclonic 36 8
S-SW anticyclonic 14 9
S-SE cyclonic 10
S-SE anticyclonic 11
Cut-off 26 12
Stationary Anticyclone
COSMO General Meeting, Moscow 2010

6. WG5 COSMO General Meeting, Moscow 2010

7. Temperature Versus page WG5 COSMO General Meeting, Moscow 2010
Zonal anticyclonic
Versus page
Temperature
Cut-off Low
Stationary Anticyclone
WG5 COSMO General Meeting, Moscow 2010

8. Wind Speed COSMO General Meeting, Moscow 2010 Zonal anticyclonic
S-SW cyclonic
COSMO General Meeting, Moscow 2010

9. 12h Precipitation
ETS
COSMO General Meeting, Moscow 2010

10. 12h Precipitation
FBI
WG5 COSMO General Meeting, Moscow 2010

11. What information to include…..
In a bulletin in a user friendly format, the most important outcomes of the verification performed per month/season need to be included with guidelines or conclusions for the forecaster on duty.
What information to include…..
Results for WDV, conditional and standard verification once they are proved to reveal constant trends
COSMO General Meeting, Moscow 2010

12. 2m Temp
WINTER
Wind Speed
WG5 COSMO General Meeting, Moscow 2010

13. Temp in overcast conditions
Fall
Winter
Spring
Summer

14. Temp in ‘high wind’ conditions
Fall
Winter
Spring
Summer
WG5 COSMO General Meeting, Moscow 2010

15. Suggestions are needed!!!
The next steps….
Seasonal verification per weather class
Regional verification (east, west, north) per weather class, mainly for precipitation
Stratification of stations according to altitude and proximity to water
Extended use of conditional verification, again stratified
What is the best way to communicate the results to the forecasters?
Currently this is accomplished through seasonal presentations to the personnel of the forecasting center.
A bulletin is under development but the extracted guidelines and the information to be included is still not yet clear.
The MCH guidelines have been used as a prototype while trying to minimize the amount of graphics and including more text (forecasters request).
Suggestions are needed!!!
COSMO General Meeting, Moscow 2010