NOUS41 KWBC 061140



Service Change Notice 15-21

National Weather Service Headquarters Washington DC

740 AM EDT Mon Apr 6 2015

To:†††††† Subscribers:

††††††††† -Family of Services

††††††††† -NOAA Weather Wire Service

††††††††† -Emergency Managers Weather Information Network

††††††††† -NOAAPORT

††††††††† Other NWS Partners and NWS Employees

From:†††† Richard May

††††††††† Acting Chief, Marine, Tropical and Tsunami Services

††††††††† Branch


Subject:Experimental Gridded Lightning Strike Density product

††††††††† will transition to operational status effective

††††††††† Thursday, May 21, 2015


Effective Thursday, May 21, 2015 at 1500 Coordinated Universal

Time (UTC), 1100 AM Eastern Daylight Time, the NWS National

Centers for Environmental Predictionís (NCEP) Ocean Prediction

Center (OPC) will transition the experimental gridded lightning

strike density product to operational status. The product now

will be supported 24 hours per day, 7 days a week.


This product enhances awareness of developing and transitory

thunderstorm activity by giving users the ability to determine

whether a cloud system is producing lightning, if that activity

is increasing or decreasing, and to emulate the future GOES-R

Global Lightning mapper (GLM) data.


The Lightning Strike Density product produced by OPC will

continue to be available in gridded form (GRIB2) and also have

complimentary web images. The base data is the Vaisala GLD360

land based detection system. The gridded product is considered a

derived product and is therefore acceptable for distribution to

the public. The product contains the number of lightning strikes

per square meter, per second. Users should remember that a

lightning flash may be comprised of several or many cloud-to-

ground strikes.


GRIB2 data will be available on the OPC FTP server, accessible

via FTP and HTTP protocols:



Graphical images of the gridded product with GOES satellite

visible and IR satellite imagery will be available on the

Atlantic and Pacific pages on the Ocean Prediction Center web

page at:


Please send comments or requests for more information to:


Joseph Sienkiewicz



National Service Change Notices are available online at: