19991005: RUC grids on NOAAPort, again

IDD data users,

Some sites experienced greater latencies recently (see Gilbert's
previous "What's Wrong" question).

Rest assured, NOAAport data is still flowing to Thelma.
You can also refer back to the nws-changes message this morning
regarding expected data outages for NWSTG October 5-7; however,
the cause for some sites falling behind in the IDD data flow
today was a surge in the amount of data being sent across NWSTG.

                 Products   Bytes                      Products   Bytes
1999100416.stats  15248   51474515    1999100516.stats  12622   28636193
1999100417.stats  12880   36420311    1999100517.stats  35044  109592845
1999100418.stats  20663   79586168    1999100518.stats  23283   76889718
1999100419.stats  16920   59775736    1999100519.stats  14765   38963185
1999100420.stats  12893   36322145    1999100520.stats  12037   24207204


You may have noticed that for the past day, the HDS data stream has
carried hourly RUC model data, where previously it had been provided
3 hourly. Also today, between 17Z and 18Z, a backlog in model
runs was transmitted as follows:


17:06Z  16Z RUC transmitted
17:34Z  15Z RUC transmitted
17:40Z  16Z RUC transmitted  <<-- duplicate data in queue
17:45Z  13Z RUC transmitted
17:52Z  14Z RUC transmitted
18:06Z  17Z RUC transmitted

In other words, aside from the 16Z and 17Z RUC runs, 13Z, 14Z, and 15Z
were also transmitted within the same hour. While the MD5 checksum that
the LDM uses can identify duplication of data within the product queue,
retransmission of data on the NWSTG after it has been expired from the
product queue will lead to an increase of bandwidth usage.

It also appears that many of the hydrologic and other bulletins
transmitted on the DDPLUS|IDS data stream were retransmitted. The
retransmission may be related to the NCF work refered to this morning in
the NOUS42 KWBC message that was also sent out to the nws-changes mail
list.

Leafnode sites that do not wish to receive hourly RUC model runs
may wish to employ filtering to their request ldmd.conf lines to
ask for only the 3 hourly or other desired frequency of forecast run.

As always, if you suspect that you are having trouble with data reception,
please provide us with as much detail you can, including using the LDM
troubleshooting tools and checking data reception to your upstream site
with notifyme.

Steve Chiswell
Unidata User Support
address@hidden