-------- Original Message --------
305
NOUS41 KWBC 301902
PNSWSH
TECHNICAL IMPLEMENTATION NOTICE 10-19
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
305 PM EDT FRI APR 28 2010
TO: SUBSCRIBERS:
-FAMILY OF SERVICES
-NOAA WEATHER WIRE SERVICE
-EMERGENCY MANAGERS WEATHER INFORMATION NETWORK
-NOAAPORT
OTHER NWS PARTNERS...USERS AND EMPLOYEES
FROM: TIMOTHY MCCLUNG
SCIENCE PLANS BRANCH CHIEF
OFFICE OF SCIENCE AND TECHNOLOGY
SUBJECT: CHANGE TO RUC MODEL DISSEMINATION TIME: EFFECTIVE
APRIL 27 2010
NCEP HAS EXPERIENCED SEVERAL RECENT FAILURES OF THE RAPID
UPDATE CYCLE /RUC/ MODEL. THESE FAILURES ARE DUE TO
VIOLATIONS OF THE COURANT-FRIEDRICHS-LEVY /CFL/ STABILITY
CONDITION...WHICH CAN OCCUR IN VARIOUS SITUATIONS...BUT HAVE
BEEN EXPERIENCED RECENTLY ON THE EAST SIDE OF THE SIERRAS
WITH STRONG MOUNTAIN WAVES.
TO PREVENT THESE FAILURES...ON TUESDAY APRIL 27 AT 0006
COORDINATED UNIVERSAL TIME /UTC/ A CHANGE WAS MADE TO THE
OPERATIONAL CONFIGURATION OF THE RUC...SPECIFICALLY THE MODEL
TIME STEP.
THIS CHANGE RESULTS IN A SLIGHT DELAY TO THE OUTPUT PRODUCT
SCHEDULE:
APPROXIMATELY 1 MINUTE FOR THE 6-HR FORECAST PRODUCTS
APPROXIMATELY 2 MINUTES FOR THE 12-HR FORECAST PRODUCTS
APPROXIMATELY 3 MINUTES FOR THE 18-HR FORECAST PRODUCTS
NCEP WILL RUN THE RUC IN THIS OPERATIONAL CONFIGURATION UNTIL
FURTHER NOTICE. THESE CHANGES ARE NECESSARY TO ELIMINATE
INTERMITENT MODEL FAILURES WHICH RESULT IN SIGNIFICANTLY
LATER PRODUCT ARRIVAL TIMES OR MISSING DATA FOR SOME CYCLES.
IF YOU HAVE QUESTIONS OR CONCERNS ABOUT THIS CHANGE...PLEASE
CONTACT:
REBECCA COSGROVE
NCEP/NCO DATAFLOW GROUP
CAMP SPRINGS MARYLAND
PHONE: 301-763-8000 X7148
EMAIL: NCEP.PMB.DATAFLOW@xxxxxxxx
NWS NATIONAL TECHNICAL IMPLEMENTATION NOTICES ARE ONLINE AT
/USE LOWERCASE/:
HTTP://WWW.NWS.NOAA.GOV/OS/NOTIF.HTM
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