Tropical Cyclone GONU

2.  NWP Models at DGMAN
 Study Domain and Configurations
 GME (Global Model) analysis as an Input to
HRM/COSMO
 Evaluating Forecasted:
 Tracks
 Intensity
 rainfall
 Conclusion & future work

3. Operational Forecasting Model
Prognostic variables Diagnostic variables
Surface pressure ps
Temperature T Vertical velocity ω
Water vapour qv Geopotential φ
Cloud water qc Cloud cover clc
Cloud ice qi Diffusion coefficients tkvm/h
Horizontal wind u, v
Several surface/soil parameters

4. Research Evaluation Model
Prognostic variables Diagnostic variables
pressure perturbation p‘
Temperature T Total air density
specific humidity qv precipitation fluxes of rain
Cloud water qc and snow.
Cloud ice qi
Horizontal/virtical
wind u, v,w

5.  x: 193
 y:114
 levels: 40
 FCT Hours:78
 FCT times: 00,12 UTC
 7 – 35.25 N
 30 – 78 E
 Initial/LBC: GME

6.  x: 241
 y: 241
 levels : 40
 FCT Hours:78
 FCT times: 00,12 UTC
 14.0 – 29.0 N
 48.5 – 63.5 E
 Initial/LBC: GME

7.  x: 241 y: 241 levels :40
 Lat: 11.0 – 26 N
 Lon: 57.0 – 72.0 E
 Initial/LBC: GME
 Period: 3-6 June 2007
 Model Version:
 HRM 2.4
 COSMO 3.4

15. Category Wind Speed
Deep kt 28-33
Depression
Cyclonic kt 34-47
Storm
Severe kt 48-63
Cyclonic
Storm
Very Severe 64-119kt
Cyclonic
Storm
Super kt 120=<
Cyclonic
Storm

16. mm

17. mm

18. mm

19.  GME (driving model) miss located Gonu center and underestimated the
associated wind and pressure drop.
 Clear dependency between GME forecast quality and HRM/COSMO
forecast quality.
 Even though HRM/COSMO are not TC specialized models, both have
given the signal for Gonu.
 COSMO_07 were able to forecast Gonu as Severe Cyclonic Storm starting
from 12UTC run of 4th June 2007.
 On average COSMO shows 5% improvement of track forecast and 3% on
the wind intensity over HRM.
 Both HRM_07 and COSMO_07 have signaled 48h rainfall of more than
900mm starting at June 5th with reasonable spacial and good amount
agreement with the recorded rainfall.

20.  Both HRM & COSMO are not specialized TC models, Testing the new “TC
bogussing” scheme developed on the HRM community.
 Testing the effect of introducing Data Assimilation system for the HRM
model.
 Plan to introduce SREF system, and test the performance.