NOUS41 KWBC 281315 AAB



Public Information Statement PNS16-33, Updated

National Weather Service Headquarters Silver Spring MD

115 PM EST Tue Nov 28 2017


To:       Subscribers:

          -NOAA Weather Wire Service

          -Emergency Managers Weather Information Network


          Other NWS Partners and Employees


FROM:     Allison Allen

          Chief, Marine, Tropical, and Tsunami Services 



SUBJECT:    Soliciting comments on the Experimental

          Modernized Open Lakes Forecast for the Great

          Lakes through March 31, 2018


Updated to extend the comment period for the Experimental

Modernized Open Lake Forecast (GLF) through March 31, 2018, and

to expand the scope to include all five Great Lakes.


The Open Lake Forecast (GLF) is a text product issued by

five primary Great Lakes Weather Forecast Offices (WFO) to

state expected weather conditions within their marine

forecast area of responsibility through Day 5.  The primary

offices responsible for issuing the GLF are:


WFO Marquette (for Lake Superior)

WFO Detroit (for Lake Huron and Lake St. Clair)

WFO Chicago (for Lake Michigan)

WFO Cleveland (for Lake Erie)

WFO Buffalo (for Lake Ontario)


These offices routinely issue a GLF four times per day. 


During comment and review, the experimental modernized Open Lake

Forecast will be produced in parallel with the current

operational Open Lake Forecast by all five primary

Great Lakes WFOs.


The product format for the Experimental Modernized Open Lake

Forecast will be as follows:


Experimental Modernized Open Lake Forecast for Lake Xxxx

National Weather Service City State

TIME-DATE (example: 900 AM EDT Sat Sep 30 2017)






TIME-DATE (example: 900 AM EDT Sat Sep 30 2017)






Sfc winds....Knots

100-FT Winds....Knots

Sig waves........Feet/meters

Ocnl waves (Highest 10 percent whenever wave heights of six feet

or higher are forecast)...Feet/meters









Weather...Surface wind...Significant waves


(dollar sign, dollar sign)


This forecast is arranged in an easy to read format and provides

weather, wind and wave information.  The mandatory elements are

surface and 100-foot wind speed/direction, significant waves,

maximum (occasional) waves and significant weather. 


The Day 3-5 forecast will be in narrative format and will only

include weather, significant wave height, and surface wind speed

and direction. Before the end of the evaluation period,

additional elements may be added to the format to test the

capacity for expansion within the GLF. This could include

Probability of Gale Force wind, return frequency of maximum

(occasional) waves, or wave period. 


This experimental product format is available online at:


as well as a side-by-side comparison between modernized and

existing formats. For details on this product enhancement, see

the following Product Description Document (PDD):


Please provide comments by March 31, 2018, on the proposal to

provide the Modernized Open Great Lakes Forecast at all Great

Lakes offices using the following link:


During this comment period, a proactive effort will be made

to educate users and partners of the product availability

and use. At the end of the comment period, a decision will be

made to choose one of the following options:


-Transition to operational at all Great Lakes Forecast Offices

-Extend the comment period

-Discontinue the enhancement


For questions on this product, contact:


Brian Hirsch

Transportation Sector Services Program Manager

Kansas City, MO 64153-2371



National Public Information Statements are online at: