Mesoscale model support for the 2005 MDSS demonstration

Paul SchultzNOAA/Earth System Research Laboratory

Global Systems Division(formerly Forecast Systems Laboratory)

Domain for 2005 MDSSdemonstration

Ensemble configuration

• Two models (WRF, MM5)

• Re-initialized with new radar, satellite data every hour– Surface obs, profilers, GPS vapor, ACARS …

• Forecasts out to 18 hours

• Transmitted in real time to NCAR

Temperature verification statistics

  Temperature (deg C)

Wind speed (m/s)

Dewpoint (deg C)

RMS bias RMS bias RMS bias

MM5 3.2 +0.2 2.4 +1.6 3.7 +1.5

WRF 3.0 +1.3 2.3 +1.3 3.7 +2.2

Eta 2.7 +0.5 2.7 -0.2 2.6 +1.7

Table 1. 12-h forecast verification statistics from the 2004 MDSS demonstration conducted in Iowa.

Temperature (deg C)

Wind speed (m/s)

Dewpoint (deg C)

RMS bias RMS bias RMS bias

MM5 3.2 +0.9 2.2 +0.7 3.3 +1.5

WRF 3.2 +1.0 2.2 +1.2 3.9 +2.2

Eta 2.3 +0.5 2.1 +0.4 2.8 +1.1

Table 2. 12-h forecast verification statistics from the 2005 MDSS demonstration conducted in Colorado.

A closer lookWRF temperature bias

-1

-0.5

0

0.5

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1.5

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0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34

Forecast hour

Bia

s (d

eg C

)

00Z

01Z

02Z

03Z

04Z

05Z

06Z

07Z

08Z

09Z

10Z

11Z

12Z

Figure 5. Time series of temperature forecast biases from WRF.

Case of 10 April 2005

WRF temperature forecasts

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0

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4/10/05 0:00 4/10/05 6:00 4/10/05 12:00 4/10/05 18:00 4/11/05 0:00 4/11/05 6:00 4/11/05 12:00

time

tem

per

atu

re

observations

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12Z

18Z

00Z

Eta temperature forecasts

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0

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4/10/05 0:00 4/10/05 6:00 4/10/05 12:00 4/10/05 18:00 4/11/05 0:00 4/11/05 6:00 4/11/05 12:00

time

tem

pera

ture

observations

00Z

06Z

12Z

18Z

00Z

Precipitation verification

Figure 7. Three-hour precipitation forecast verification from the 2004 MDSS demonstration in Iowa.

Figure 8. Three-hour precipitation forecast verification from the 2005 MDSS demonstration in Colorado.

LAPS hot start initialization eliminates precipitation spin-up in

numerical weather predictionEquitable skill score for WRF QPF > .01"

during 2005 MDSS demonstration

0

0.05

0.1

0.15

0.2

0.25

1 2 3 4 5 6 7 8 9 10 11 12

Forecast (h)

Eq

uit

able

ski

ll s

core

WRF

Typical spin-up (artist’s

conception)

Issues

• Vertical resolution– Resolving shallow cold air masses– Time step impacts

• Surface fluxes– Implementation of HRLDAS– Assimilation of soil temperature data

• Initialization– Hot start errors– Detection/correction of upstream problems

• Funding– Future is severely threatened