NOUS41 KWBC 301551



Public Information Notice, Comment Request

National Weather Service Headquarters Washington DC

1052 AM EST Mon Dec 3 2012


To:      Subscribers:

         -Family of Services

         -NOAA Weather Wire Service

         -Emergency Managers Weather Information Network


         Other NWS Partners and NWS Employees


FROM:    Eli Jacks

         Chief, Fire and Public Weather Services Branch


SUBJECT: Soliciting Comments Until March 15, 2013, on an

         Experimental Scaled Predictive Ice Storm Aftermath

         Index at Select NWS Weather Forecast Offices


NWS is accepting comments from December 4, 2012, through March

15, 2013, on an experimental Scaled Predictive Ice Storm

Aftermath (SPIA) Index.


Select NWS Weather Forecast Offices (WFOs) (Table 1) will produce

Web graphics depicting the potential impact of freezing rain and

wind on exposed electrical systems to enhance their decision

support services.


Current NWS Ice Storm Warnings are issued based on forecast ice

accumulation only, typically one quarter of an inch or greater. 

The combined effect of ice and wind, which more realistically

describes damage potential, is not formally set as warning



By using the SPIA scaled index, NWS should be able to provide a

better understanding of ice storm impact potential to local,

state, and federal response entities.  The potential impacts are

scaled from 0 to 5 and suggest potential electrical outage

coverage and duration.


Until now, the NWS has not attempted to routinely quantify the

impact of ice storms.  The use of this scaled index will allow

the NWS to evaluate the potential of providing these specifics. 

For example, a level 5 ice storm would be defined as one causing

catastrophic damage to entire exposed utility systems, including

both distribution and transmission networks.  Outages could last

several weeks in some locations.


Graphics showing forecast index values will be available as part

of the routine forecast provided online for the following WFOs:


Table 1:  Participating WFOs and url:

--------  ---------------------------

WFO Tulsa (TSA)


WFO Springfield (SGF)


WFO Pleasant Hill (EAX)


WFO St. Louis (LSX)


WFO Paducah (PAH)


More information regarding the SPIA index is online in a Product

Description Document:


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, the NWS will make a decision on

whether to transition the experimental SPIA Index to operational

status. The experimental SPIA Index may also be considered for

use at other WFOs and NWS Regions.


For more information please contact:


Steven Piltz


National Weather Service

Tulsa, OK 74128



National Public Information Statements are online at: