20050328: upgrade eof the north american mesoscale eta sys-ADMIN NOTICE

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: 20050328: upgrade eof the north american mesoscale eta sys-ADMIN NOTICE
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: Mon, 28 Mar 2005 11:57:11 -0700

730
NOUS41 KWBC 281852
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 05-25
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
150 PM EST MON MAR 28 2005

TO:     FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER
WIRE SERVICE /NWWS/ SUBSCRIBERS...EMERGENCY MANAGERS
WEATHER INFORMATION NETWORK /EMWIN/ SUBSCRIBERS...OTHER
NATIONAL WEATHER SERVICE /NWS/ CUSTOMERS AND
PARTNERS...NWS EMPLOYEES

FROM:   PAUL HIRSCHBERG
       CHIEF...SCIENCE PLANS BRANCH
       OFFICE OF SCIENCE AND TECHNOLOGY /OST/

SUBJECT:  UPGRADE OF THE NORTH AMERICAN MESOSCALE /ETA/ SYSTEM
 EFFECTIVE...MAY 03 2005

EFFECTIVE MAY 03 2005...BEGINNING WITH THE 1200 COORDINATED
UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL
PREDICTION /NCEP/ WILL UPGRADE THE NORTH AMERICAN MESOSCALE /NAM/
SYSTEM...FORMERLY THE MESO ETA SYSTEM AND THE DOWNSCALED GFS BY
ETA EXTENSION /DGEX/ TO IMPROVE THEIR ACCURACY AND PRODUCTS.

THIS UPGRADE WILL INVOLVE INCREMENTAL IMPROVEMENTS TO ALL THE
COMPONENTS OF THE NAM:

OBJECTIVE ANALYSIS /3DVAR/
DATA ASSIMILATION
PREDICTION MODEL /MESO ETA/
AND OUTPUT PRODUCTS.

THE CHANGES FOR THIS UPGRADE ARE AS FOLLOWS:

3DVAR ANALYSIS CHANGES:

RE-INTRODUCE SURFACE TEMPERATURE OBSERVATIONS FROM ALL ON-
TIME OVERLAND SITES.
ASSIMILATE NEXRAD LEVEL 2.5 RADIAL WIND DATA /THESE ARE
THE SUPEROBS CONSTRUCTED AT INDIVIDUAL WSR-88D LOCATIONS
BEFORE TRANSMISSION/

NDAS DATA ASSIMILATION CHANGES:

IMPROVE ROBUSTNESS OF PRECIPITATION ASSIMILATION BY USING
OBSERVED PRECIPITATION DIRECTLY IN DRIVING THE LAND-
SURFACE MODEL AND ELIMINATING THE OPTION TO AGGRESSIVELY
CREATE PRECIPITATION.

PREDICTION MODEL CHANGES:
MODIFIED COMPONENTS AND COEFFICIENTS IN THE RADIATION
SCHEME TO SEE CLOUDS BETTER VIA CHANGES TO THE COMPUTATION
OF OPTICAL CLOUD DEPTHS.
CLOUD COVER FORMULATION CHANGED TO ALLOW FOR MORE PARTIAL
CLOUDINESS.
REFINE NUMEROUS ASPECTS OF THE LAND-SURFACE
PHYSICS...INCLUDING USE OF HIGH-RESOLUTION SOIL TYPE AND
VEGETATION TYPE DATA SETS...AND MODIFIED SNOW EMISSIVITY
TO REDUCE THE COOL-SEASON 2-M TEMPERATURE COLD BIAS.

OUTPUT PRODUCT CHANGES:

INCLUDE EFFECTS OF CONVECTIVE RAIN RATE IN VISIBILITY
ALGORITHM.
ADD CLEAR-SKY RADIATION FLUXES...FOR EXAMPLE TO AIR
QUALITY FORECAST

THERE WILL BE NO CHANGES TO THE PRODUCTS PRODUCED AND THEIR
IDENTIFIERS.

THE NCEP ENVIRONMENTAL MODELING CENTER /EMC/ HAS ALREADY
PERFORMED A RETROSPECTIVE RUN OF THE 12-KM NDAS/NAM FOR THE
PERIOD FROM 17 JULY TO 31 AUGUST 2004.  VERIFICATION STATISTICS
FOR THESE RUNS ARE SUMMARIZED AT /USE LOWER CASE LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/PLL12STATS.ETX_17
JUL04-31AUG04/

EMC HAS BEEN RUNNING A REAL-TIME PARALLEL RUN OF THE NDAS/NAM
SINCE MID-DECEMBER 2004...AND A REAL-TIME PARALLEL DGEX SINCE 1
JANUARY 2005. BOTH ARE EXPECTED TO CONTINUE UNTIL IMPLEMENTATION.
REAL-TIME PARALLEL RUNS FROM THE NAM CAN BE VIEWED AT /USE LOWER
CASE LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/ETAPLLSUP12.ETAX_
OPSTEST/

WHILE THE REAL-TIME DGEX PARALLEL RUN FOR CONUS CAN BE VIEWED AT
/USE LOWER CASE LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/DGEXPLL.CONUS/IND
EX.HTML

AND THE REAL-TIME DGEX PARALLEL RUN FOR ALASKA CAN BE VIEWED AT
/USE LOWER CASE LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/DGEXPLL.AK/INDEX.
HTML

SUMMARIES OF VERIFICATION STATISTICS ARE AVAILABLE AT THE
FOLLOWING LOCATIONS:

FOR NAM REAL-TIME PARALLEL STATS 12/14/04-3/9/05 /USE LOWER CASE
LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/PLL12STATS.ETX_14DE
C04-20MAR05/

AND FOR DGEX REAL-TIME PARALLEL STATS 1/1/05-3/10/05 /USE LOWER
CASE LETTERS/:

HTTP://WWWT.EMC.NCEP.NOAA.GOV/MMB/MMBPLL/PLLSTATS.DGEXX_01JA
N05-20MAR05/

IF YOU HAVE ANY QUESTIONS CONCERNING THESE CHANGES...PLEASE
CONTACT:

DR. GEOFF DIMEGO
NCEP...MESOSCALE MODELING BRANCH CHIEF
CAMP SPRINGS MARYLAND
PHONE: 301 763 8000 X7221
EMAIL: GEOFF.DIMEGO@xxxxxxxx

OR

ERIC ROGERS
NCEP...MODEL DEVELOPMENT TEAM LEAD
CAMP SPRINGS MARYLAND
PHONE: 301 763 8000 X7227
EMAIL: ERIC.ROGERS@xxxxxxxx

THIS AND OTHER NWS TECHNICAL IMPLEMENTATION NOTICES ARE AVAILABLE
ONLINE AT /USE LOWER CASE LETTERS/:

HTTP://WWW.NWS.NOAA.GOV/OM/NOTIF.HTM

$$
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