NHC Important Notices

May 15, 2013
National Safe Boating Week, May 18-24, 2013

April 15, 2013
Extension of Comment Period for Experimental Wind Speed Probabilities-Based Tropical Cyclone Danger Graphic From May 13, 2013 Through November 30, 2013

April 15, 2013
Extending Comment period for Experimental Satellite Rainfall Quantitative Precipitation Estimates (QPE) from May 15, 2013 Through November 30, 2013

April 8, 2013
Transition of National Hurricane Center Audio Briefings from Experimental to Operational Effective June 1, 2013

April 4, 2013
Change in Tropical Cyclone Watch and Warning Definitions to Include Post-Tropical Cyclones Effective June 1, 2013

March 21, 2013
Amended: Experimental Gridded Marine Offshore and High Seas Forecasts in the National Digital Forecast Database (NDFD) Effective Wednesday March 20, 2013

March 5, 2013
Elimination of the Tropical Cyclone Position Estimate Product with the information provided in the Tropical Cyclone Update Product Effective May 15, 2013

March 5, 2013
NWS Transitioning from Deterministic To Probabilistic Storm Surge Forecasts effective with the 2013 Hurricane Season

November 9, 2012
Amended: GovDelivery Dissemination of NWS Alerts by email/SMS

March 1, 2012
Minor Modification of Saffir-Simpson Hurricane Wind Scale Thresholds Effective May 15, 2012

January 30, 2012
Change to the Tropical Weather Outlook Text Products Effective May 15, 2012

December 6, 2011
Changes in Offshore Waters Marine Zones For the Caribbean and Southwest North Atlantic And the Gulf of Mexico Effective April 3, 2012

September 23, 2011
Comments Sought on Proposed Change to Offshore Waters Marine Zones for the Caribbean, Southwest North Atlantic and Gulf of Mexico through October 31, 2011

September 23, 2011
Soliciting Comments for Experimental Satellite Rainfall Quantitative Precipitation Estimates (QPE) through through Novemeber 30, 2012

August 9, 2011
Soliciting Comments for Experimental Probabilistic Tropical Cyclone Inundation Guidance Products through November 30, 2011

February 2, 2011
Change to MND Header for Spanish Language Version of Tropical Cyclone Products: Effective June 1, 2011

January 21, 2011
Changes to Tropical Cyclone Text Products: Effective May 15, 2011

October 1, 2010
Change to official name of issuing office in National Hurricane Center products: Effective January 10, 2011

March 8, 2010
Change to Coding of High Density Observation (HDOB) Message for Missing Data: Effective July 15, 2010

February 16, 2010
Format Changes to the Tropical Cyclone Update Products for the 2010 hurricane season

January 26, 2010
Format Changes to the Tropical Cyclone Public Advisory for the 2010 hurricane season

January 20, 2010
Comments Requested for 2010 Experimental Tropical Cyclone Probabilistic Storm Surge Exceedance Products

January 15, 2010
Adoption of the term "Post-Tropical Cyclone" Terminology by the National Weather Service

January 5, 2010
Change to Issuance Criteria for Tropical Cyclone Watches and Warnings for 2010

July 23, 2009
Comments Requested for 2009 Experimental Tropical Cyclone Probabilistic Storm Surge Exceedance Products

June 5, 2009
Tropical Cyclone Storm Surge Display Program Now Online

May 18, 2009
Proposed Changes to Saffir-Simpson Hurricane Wind Scale - Comment Request until November 30, 2009

April 22, 2009
Format Changes to the Hurricane Local Statement (HLS) Effective June 1, 2009

April 10, 2009
Format Changes to the Tropical Cyclone Public Advisory Effective May 15, 2009 (Correction)

February 24, 2009
Changes to Storm Surge Information in Tropical Cyclone Public Advisories Effective May 15, 2009

February 24, 2009
Atlantic and Eastern Pacific Tropical Cyclone Wind Field Graphics Operational Effective May 15, 2009

February 24, 2009
Atlantic and Eastern Pacific Graphical Tropical Weather Outlooks Operational Effective May 15, 2009

February 24, 2009
Probabilistic Hurricane Storm Surge Products become Operational and Expand in Thresholds Effective June 1, 2009

February 20, 2009
Discontinuation of Special Tropical Disturbance Statements and Beginning of Speical Tropical Weather Outlooks Effective May 15, 2009

February 20, 2009
Format Change to the Tropical Cyclone Discussion for the Atlantic Basin Effective June 1, 2009

February 20, 2009
Format Change to the Monthly Tropical Weather Summary Effective May 15, 2009

April 25, 2008
New Official Storm Surge Probability Product

April 22, 2008
Comments Requested for 2008 Experimental Probabilistic Hurricane Storm Surge Products (Corrected)

April 16, 2008
Tropical Cyclone Watch/Warning (TCV) to be issued for Southern California Coast in 2008

April 9, 2008
Comments Requested for 2008 Experimental Tropical Cyclone Wind Field Graphic

March 18, 2008
Comments Requested for the 2008 Experimental Graphical Tropical Weather Outlook
New Issuance Times for Text Tropical Weather Outlooks: Effective May 15, 2008 and June 1, 2008

March 17, 2008
Changes to the Tropical Cyclone Probabilistic Wind Speed Text Products: Effective May 15, 2008
Changes to the Maximum 1-Minute Wind Speed Probability Product: Effective May 15, 2008

March 11, 2008
Enhancement to the TEMPDROP message: Effective May 15, 2008

February 28, 2008
Change to the Tropical Cyclone Public Advisory Product for the Eastern Pacific: Effective May 15, 2008

January 30, 2008
Headers for High Seas Forecasts to be Modified on July 1, 2008

January 8, 2008
FTPMAIL Service Transition

June 13, 2007
Comments Requested for Experimental Graphical Tropical Weather Outlook

May 4, 2007
Comments Requested for Experimental Probabilistic Hurricane Storm Surge Products

May 1, 2007
Tropical Cyclone Probabilistic Wind Speed Elements to be operational in NDFD

April 16, 2007
Changes to Tropical Cyclone Probabilistic Wind Speed Products

March 16, 2007
Enhancement to the Vortex Data Message Product

March 7, 2007
DOD Reconnaissance Aircraft – Data and Product Changes
High Density Aircraft Observations – Product and Format Changes
Enhancement to Aviation Tropical Cyclone Advisory Product

February 22, 2007
Changes to the 2007 Tropical Cyclone Guidance Message

January 9, 2007
Scheduled Test of 2007 Tropical Cyclone Product

October 23, 2006
Changes to 2007 Tropical Cyclone Probabilistic Wind Speed Products

June 5, 2006
National Digital Forecast Database Elements (2006 Probabilistic Wind Speed)

May 18, 2006
Change in 2006 Time Format for TCM and TCA

May 5, 2006
2006 Experimental Probabilistic Hurricane Storm Surge Products

May 2, 2006
Change to 2006 Vortex Data Message Product Format
2006 Experimental Tropical Cyclone Watch/Warning Comment Request

February 9, 2006
2006 Changes to Mass News Media Disseminator Header

February 8, 2006
New 2006 Tropical Cyclone Product – Examples page
Changes in 2006 Tropical Cyclone Probabilistic Products – Examples page