Public Information Statement
Issued by NWS National HQ
Issued by NWS National HQ
841 NOUS41 KWBC 021540 AAB PNSWSH Service Change Notice 24-69 Updated National Weather Service Headquarters Silver Spring MD 1140 AM EDT Wed Oct 2 2024 To: Subscribers: -NOAA Weather Wire Service -Emergency Managers Weather Information Network -NOAAPort Other NWS Partners, Users and Employees From: Stephen W. Bieda III, Ph.D., Chief Severe, Fire, Public, and Winter Weather Services Branch Subject: Updated: Changes to Public Forecast Zones for WFO Seattle, WA: Effective March 2025 Updated to announce the implementation date is changing from September 2024 to March 2025. The NWS Weather Forecast Office (WFO) in Seattle, WA (SEW) zone changes to Public Weather Forecast Zones for western Washington are delayed until March 2025. An updated Service Change Notice (SCN) will be provided when a date is set. After this change, all forecasts and related products will use the new zone numbers and names shown below. These changes are intended to allow WFO Seattle to issue weather watches, warnings, and advisories which will more accurately reflect forecasted weather conditions for a wide variety of weather scenarios. These changes will be most beneficial during the following scenarios: Puget Sound Convergence Zone snowfall events, snowfall events where mountain valley communities are not impacted, coastal flooding events, and tsunami events. These changes could also allow WFO Seattle to explore transitioning to zone-based hydrologic services in the future. WFO Seattle Public Forecast Zones will be reconfigured using carefully selected elevation thresholds, local climatology, major transportation routes, and main population centers. They will also align better with recent zone changes implemented by WFOs Portland, OR; Pendleton, OR; and Spokane, WA: * SCN 23-116: Changes to Public Forecast Zones for WFO Portland, OR: Effective March 5, 2024 * SCN 22-120: Changes to Public Weather Forecast Zones for WFO Pendleton, OR: Effective March 8, 2023 * SCN 21-63: Reconfiguration of Public Forecast Zones by WFO Spokane, WA: Effective September 8, 2021 Table 1: Universal Geographic Codes (UGCs): Current Public Zone Forecast Name ---------------------------------- WAZ001: San Juan County WAZ503: Western Whatcom County WAZ504: Southwest Interior WAZ506: Western Skagit County WAZ507: Everett and Vicinity WAZ509: Tacoma Area WAZ510: Admiralty Inlet Area WAZ511: Hood Canal Area WAZ512: Lower Chehalis Valley Area WAZ513: Olympics WAZ514: Eastern Strait of Juan de Fuca WAZ515: Western Strait of Juan de Fuca WAZ516: North Coast WAZ517: Central Coast WAZ555: East Puget Sound Lowlands WAZ556: Bellevue and Vicinity WAZ558: Seattle and Vicinity WAZ559: Bremerton and Vicinity WAZ567: West Slopes North Cascades and Passes WAZ568: West Slopes North Central Cascades and Passes WAZ569: West Slopes South Central Cascades and Passes Table 2: UGC: New Public Zone Forecast Name ------------------------------- WAZ001: San Juan County WAZ301: Cascades of Whatcom and Skagit Counties WAZ302: Cascades of Snohomish and Northern King Counties WAZ303: Cascades of Southern King County WAZ304: Cascades of Pierce and Lewis Counties WAZ305: Foothills and Valleys of the North Cascades WAZ306: Foothills and Valleys of Snohomish and Northern King Counties WAZ307: Foothills and Valleys of Central King County WAZ308: Foothills and Valleys of Pierce and Southern King Counties WAZ309: Foothills and Valleys of Thurston and Lewis Counties WAZ310: Lowlands of Western Whatcom County WAZ311: Lowlands of Western Skagit and Northwestern Snohomish Counties WAZ312: Downtown Everett / Marysville Area WAZ313: Shoreline / Lynnwood / South Everett Area WAZ314: Eastside WAZ315: City of Seattle WAZ316: Lowlands of Pierce and Southern King Counties WAZ317: Olympia and Southern Puget Sound WAZ318: Lowlands of Lewis and Southern Thurston Counties WAZ319: Middle Chehalis River Valley WAZ320: Willapa and Black Hills WAZ321: Southern Hood Canal WAZ322: Northern Hood Canal WAZ323: Eastern Kitsap County WAZ324: Port Townsend Area WAZ325: Eastern Strait of Juan de Fuca WAZ326: Western Strait of Juan de Fuca WAZ327: Lake Crescent Area including US 101 WAZ328: Olympics WAZ329: Foothills of the Western and Southern Olympic Peninsula WAZ330: Northern Washington Coast WAZ331: Grays Harbor County Coast WAZ332: Lower Chehalis River Valley WAZ333: Island County Table 3: NWS Seattle, WA Products Affected by these Public Zone Changes Product Name WMO HeadingAWIPS ID ------------------------ -------------------- Zone Forecast Product FPUS56 KSEWZFPSEW Point Forecast Matrix FOUS56 KSEWPFMSEW Tabular State Forecast FPUS66 KSEWSFTSEW Public Information Statement NOUS46 KSEWPNSSEW Non-Precipitation Watch/ WWUS76 KSEWNPWSEW Warning/Advisory Special Weather Statement WWUS86 KSEWSPSSEW Winter Weather Message WWUS46 KSEWWSWSEW Coastal Hazard Message WHUS46 KSEWCFWSEW Area Forecast Discussion FXUS66 KSEWAFDSEW Avalanche Watch WOUS46 KSEWAVASEW Avalanche Warning WOUS46 KSEWAVWSEW Special Avalanche Bulletin WWUS86 KSEWSABSEW NTWC Segmented Tsunami WEPA41 PAAQTSUWCA Watch/Warning/Advisory Final versions of the shapefiles will be available around March 2025, with the exact date announced in December. A graphical depiction of this change is online at: https://arcg.is/1eH80e0 For more information, please contact: Reid Wolcott Warning Coordination Meteorologist NWS Seattle, WA reid.wolcott@noaa.gov National Service Change Notices are online at: https://www.weather.gov/notification/