20050606: RUC upgrade-ADMIN NOTICE NOUS41 KWBC (fwd)

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679
NOUS41 KWBC 061753
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 05-40
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
1125 AM EDT MON MAY 23 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 RAPID UPDATE CYCLE /RUC/ FORECAST SYSTEM 
EFFECTIVE...JUNE
28 2005

EFFECTIVE JUNE 28 2005...BEGINNING WITH THE 1200 COORDINATED UNIVERSAL TIME 
/UTC/
RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE THE
RAPID UPDATE CYCLE /RUC/ FORECAST SYSTEM TO IMPROVE ITS ACCURACY AND PRODUCTS.  
THE
UPGRADE IS INTENDED TO PROVIDE IMPROVEMENTS TO THE FOLLOWING AREAS OF THE 
FORECAST
GUIDANCE:

-CLOUD
-CEILING
-VISIBILITY
-ICING FORECASTS
-TEMPERATURE AND DEWPOINT FORECASTS AT THE SURFACE AND IN THE LOWER TROPOSPHERE
-PRECIPITATION FORECASTS.

THE FOLLOWING MODIFICATIONS TO THE RUC MODEL WILL BE MADE IN ORDER TO ACHIEVE 
THESE
IMPROVEMENTS:

- INCREASE THE HORIZONTAL RESOLUTION FROM 20 KM TO 13.3 KM.   USE NEW HIGHER
RESOLUTION /ALSO 13 KM/ FIXED FILES FOR TERRAIN ELEVATION/ LAND USE /WITH 
LAND-SEA
MASK/ SOIL TYPE/ AND ROUGHNESS LENGTH.

-MODIFY GRELL-DEVENYI CONVECTIVE PARAMETERIZATION TO USE OPTIMIZED WEIGHTING FOR
MULTIPLE CLOSURES FOR IMPROVED FORECASTS OF CONVECTIVE PRECIPITATION.

-IMPLEMENT UPDATED VERSION OF RUC/NCAR BULK MIXED-PHASE CLOUD MICROPHYSICS 
DESIGNED
TO PRODUCE MORE ACCURATE DEPICTION OF SUPERCOOLED LIQUID WATER NEEDED FOR ICING
FORECASTS.

-THE INITIALIZATION OF LOW-LEVEL MOISTURE FIELDS IS GREATLY IMPROVED BY:
1. MODIFYING THE MOISTURE ANALYSIS VARIABLE FROM LOG OF WATER VAPOR MIXING 
RATIO TO
PSEUDO-RELATIVE-HUMIDITY  2. MODIFYING RUC MODEL DIGITAL FILTER INITIALIZATION
3. ASSIMILATING NEW OBSERVATIONS FROM GPS PRECIPITABLE WATER AND IMPROVING THE
QUALITY CONTROL FOR PRECIPITABLE WATER DATA.

-ADD SOIL TEMPERATURE AND MOISTURE NUDGING IN ANALYSIS, ONLY INCLUDED UNDER 
CERTAIN
CONSERVATIVE CONDITIONS, BASED ON NEAR-SURFACE ANALYSIS INCREMENTS OF 
TEMPERATURE
AND MOISTURE.  THIS LEADS TO SIGNIFICANT IMPROVEMENTS IN 2-    METER 
TEMPERATURE AND
DEW POINT FIELDS AS WELL AS INSTABILITY FORECASTS AND RESULTANT
CONVECTIVEPRECIPITATION.

-ASSIMILATE NEW OBSERVATIONS MESONET SURFACE STATIONS AND
BOUNDARY-LAYER WIND PROFILERS TO IMPROVE SURFACE ANALYSIS.
-ASSIMILATE METAR OBSERVATIONS OF CLOUD LEVELS AND VISIBILITY TO IMPROVE INITIAL
CONDITIONS FOR RUC 3-D HYDROMETEOR FIELDS.

THE ENVIRONMENTAL MODELING CENTER (EMC) IS CURRENTLY RUNNING A NEAR REAL-TIME
PARALLEL OF THIS NEW VERSION OF THE RUC FOR ALL MODEL CYCLES.  EMC HAS A WEB 
PAGE
DISPLAYING MODEL OUTPUT OF THESE PARALLEL RUNS VS. THE OPERATIONAL RUNS.  THIS 
WEB
PAGE CAN BE FOUND ONLINE AT /USE LOWER CASE LETTERS/:

HTTP://WWW.EMC.NCEP.NOAA.GOV/MMB/RUC2/PARA/

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

GEOFF MANIKIN
NCEP...MESOSCALE MODELING BRANCH
CAMP SPRINGS MARYLAND
PHONE: 301 763 8000 X7263
EMAIL: GEOFFREY.MANIKIN@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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