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-------- 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@xxxxxxxxNWS NATIONAL TECHNICAL IMPLEMENTATION NOTICES ARE ONLINE AT /USE LOWERCASE/:
HTTP://WWW.NWS.NOAA.GOV/OS/NOTIF.HTM
$$
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