NOUS41 KWBC 231415

PNSWSH

Service Change Notice 13-5

National Weather Service Headquarters Washington DC

910 AM EST Wed Jan 23 2013

TO:          Subscribers:

             -Family of Services

             -NOAA Weather Wire Service

             -Emergency Managers Weather Information Network

             -NOAAPORT

             Other NWS partners and NWS employees

FROM:        Mark Tew

             Chief, Marine and Coastal Services Branch

SUBJECT:     Changes to the Wind Information in the Remarks

             Section of the Vortex Data Message for Tropical

             Cyclones in the Atlantic, Eastern Pacific, 

             Central Pacific and Western Pacific Hurricane Basins

             Effective May 15, 2013

To minimize confusion, provide greater precision to users, and increase consistency with other storm-related items, the changes detailed below will become effective on May 15, 2013. The changes affect the Vortex Data Message (VDM) reported from Department of Defense (DOD) and NOAA aircraft conducting reconnaissance missions for tropical cyclones. There are no changes to WMO Headers or AWIPS IDs for the VDMs.

Currently, the Remarks Section (Data Item P) of the VDM identifies the location(s) of maximum flight level winds by the relative quadrant of the storm, followed by the word QUAD. 

Old format:

MAX FLT LVL WIND 77 KT N QUAD 01:23:40Z

MAX OUTBOUND FLT LVL WIND 77 KT N QUAD 01:23:40Z

MAX OUTBOUND AND MAX FLT LVL WIND 77 KT N QUAD 01:34:40Z

Beginning on May 15, 2013, the word QUAD will be removed from the

Remarks Section and replaced with the observed bearing (in degrees) and range (in nautical miles), relative to the center fix of the overall tropical cyclone maximum flight level winds.

New format:

MAX FLT LVL WIND 77 KT 357/12 01:23:40Z

MAX OUTBOUND FLT LVL WIND 77 KT 357/12 01:23:40Z

MAX OUTBOUND AND MAX FLT LVL WIND 77 KT 357/12 01:23:40Z

In addition, the reference to "the latest pass through any portion of the storm" in the National Hurricane Operations Plan (NHOP), Table 5-2, Data Item P, will be removed.  For 2013, the wording will be changed in the NHOP to refer to the latest pass through any octant of the storm, i.e., 337.5-22.5 degrees, 22.5-67.5 degrees, etc.

High-Density Observation Bulletins (HDOB) message formats are provided in the National Hurricane Operations Plan (NHOP), Chapter 5. The 2012 NHOP, along with the 2012 HDOB Message Format, is online at:

http://www.ofcm.gov

The 2013 NHOP will be posted on line by June 1, 2013, along with the new HDOB message format for 2013 in Table 5-2. A new example VDM will be provided in Figure 5-4. 

If you have questions regarding this notice, please contact:

     John F. Kuhn

     National Weather Service

     Marine and Coastal Services Branch

     Silver Spring, Maryland  20910

     Telephone:  301-713-1677 x121

     email:  john.f.kuhn@noaa.gov

Service Change Notices are online at:

     http://www.nws.noaa.gov/om/notif.htm

$$