Codes Employed

The components of the end-to-end forecast system used for this test included:

    • WRF Preprocessing System (WPS) (v2.2)

    • WRF-NMM model (Note: The WRF code used in this test does not        correspond to a public release. Instead, a snapshot of the top of        the WRF code repository as of August 29, 2007 was used. The        choice of code was based on the need to use the latest code        developments, especially the unified Noah LSM, which was not        available in the public release (WRF v2.2))

    • WRF Post Processor (WPP) (v2.2)

    • NCEP Verification System

    • NCAR Command Language (NCL) for graphics generation

    • Statistical programming language, R, to perform aggregations        and compute confidence intervals

Domain Configuration

    • Contiguous U.S. (CONUS) domain with roughly 13-km grid        spacing (selected such that it fits within the RUC13 domain)

Click thumbnail for larger image.

    • 280 x 435 gridpoints, for a total of 121,800 horizontal gridpoints

    • 451 x 337 gridpoints, for a total of 151,987 horizontal gridpoints        in the post-processed domain

    • 58 vertical levels (59 sigma entries)

    • Rotated Latitude-Longitude map projection

Sample Namelists

     namelist.wps

     namelist.input

Physics Suite

Microphysics:	Ferrier
Radiation (LW/SW):	GFDL
Surface Layer:	Janic
Land Surface:	Noah
PBL:	Mellor-Yamada-Janjic
Convection:	Betts-Miller-Janjic

Other run-time settings

    • Long timestep = 30 s

    • Calls to the boundary layer, microphysics and cumulus        parameterization were made every other time step

    • Calls to radiation were made every 30 minutes

    • Sample namelist.input

The end-to-end system for this test did not include a data assimilation component.

Initial and Boundary Conditions

    • Initial conditions (ICs) and Lateral Boundary Conditions        (LBCs): North American Mesoscale Model (NAM212)
       (Note: For the retrospective period used, the forecast component of        the NAM was the Eta model.)

    • Sea Surface Temperature (SST) Initialization: NCEPs daily,        real-time SST product

Cases Run

    • Forecast Dates by season:
        • Summer: 09 July - 24 August 2005
        • Fall: 10 October - 23 November 2005
        • Winter: 10 January - 22 February 2006
        • Spring: 10 April - 23 May 2006

    • Initializations: Every 36 hours, therefore, alternating 00 and        12 hr cycles

    • Forecast Length: 60 hours; output files generated every 3        hours

The table below lists the forecast cases that were not verified due to the reasons described in the table.

Missing Verification:

Forecast cycle	Affected Case	Missing Data	Reason
Winter	2006011300	Incomplete 24-hr and 3-hr QPF verification	Missing RFC and ST2 analysis
	2006011412	Incomplete 24-hr and 3-hr QPF verification	Missing RFC and ST2 analysis
	2006011712	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2006011900	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2006021312	Incomplete 3-hr QPF verification	Corrupt ST2 analysis
	2006021500	Incomplete 3-hr QPF verification	Corrupt ST2 analysis
	2006021612	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2006021800	Incomplete sfc/ua verification	Missing RUC Prepbufr
Fall	2005101212	Incomplete 3-hr QPF verification	Corrupt ST2 analysis
	2005103012	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2005110100	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2005110812	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2005111000	Incomplete sfc/ua verification	Missing RUC Prepbufr
Spring	2006042200	Incomplete 24-hr QPF and sfc/ua verification	Missing RFC analysis and RUC Prepbufr
	2006042312	Incomplete 24-hr QPF and sfc/ua verification	Missing RFC analysis and RUC Prepbufr
	2006050100	Incomplete 3-hr QPF verification	Missing ST2 analysis
	2006051300	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2006051412	Incomplete sfc/ua verification	Missing RUC Prepbufr
	2006052312	Incomplete sfc/ua verification	Missing RUC Prepbufr
Summer	2005070912	Incomplete 3-hr QPF verification (at 60-hr)	Unknown
	2005072812	Incomplete 3-hr QPF verification (at 60-hr)	Unknown

Verification

The NCEP Verification System is comprised of:
    • Surface and Upper Air Verification System (grid-to-point        comparison)
    • Quantitative Precipitation Forecast (QPF) Verification        System (grid-to-grid comparison)

From these, model verification partial sums (aggregated by geographical region using the mean) were generated and objective model verification statistics were then computed using the statistical programming language, R. Confidence intervals (CIs), at the 99% level, were applied to each of the variables using the appropriate statistical method.

Objective verification statistics generated included:
    • Bias-corrected Root Mean Square Error (BCRMSE) and Mean        Error (Bias) for:
        • Surface Temperature (2 m), Relative Humidity (2 m) and            Winds (10 m)
        • Upper Air Temperature, Relative Humidity and Winds

    • Equitable Threat Score (ETS) and Frequency Bias (FBias) for:
        • 3-hr and 24-hr Precipitation Accumulation intervals

Verification results were computed for select spatial aggregations, including the entire CONUS (G164), CONUS-West (G165), and CONUS-East (G166) domains (shown here).