History of Storm Prediction Center in Timeline

The Storm Prediction Center (SPC) is a US government agency nested within NOAA, NWS, and NCEP. Its core function involves forecasting severe weather, including tornadoes, severe thunderstorms, and other hazardous meteorological events, across the United States. The SPC plays a crucial role in issuing watches and providing guidance to local NWS offices and the public, enabling timely preparations and response to potentially life-threatening weather conditions. Their forecasts and analyses are vital for public safety and emergency management.

1952: Storm Prediction Center Began as SELS

In 1952, the Storm Prediction Center began as the Severe Local Storms Unit (SELS) within the U.S. Weather Bureau in Washington, D.C. This marked the inception of a dedicated unit for forecasting severe weather events.

1954: SELS Moved to Kansas City

In 1954, the Severe Local Storms Unit (SELS) relocated its forecast operations from Washington, D.C. to Kansas City, Missouri, centralizing operations to better forecast severe weather.

1955: SELS Issued Convective Outlooks

In 1955, SELS (Severe Local Storms Unit) began issuing convective outlooks to predict thunderstorm activity, marking a significant step in forecasting severe weather.

1960: SELS Issued Radar Summaries

In 1960, SELS started issuing radar summaries in three-hour intervals, increasing its duties in compiling and disseminating radar information.

1966: SELS Became NSSFC

In 1966, the Severe Local Storms Unit (SELS) became the National Severe Storms Forecast Center (NSSFC) due to increased responsibilities in compiling and disseminating radar summaries, remaining headquartered in Kansas City.

1968: NSSFC Began Issuing Status Reports on Weather Watches

In 1968, the National Severe Storms Forecast Center (NSSFC) began issuing status reports on weather watches, enhancing the communication of severe weather threats.

1971: First Computerized Data Transmission

In 1971, the National Severe Storms Forecast Center (NSSFC) made its first computerized data transmission, marking a step towards modernizing weather forecasting operations.

April 2, 1982: First "Particularly Dangerous Situation" Watch

On April 2, 1982, the National Severe Storms Forecast Center (NSSFC) issued the first "Particularly Dangerous Situation" watch, indicating the imminent threat of a major severe weather event.

1986: Introduction of New Forecast Products

In 1986, the National Severe Storms Forecast Center (NSSFC) introduced two new forecast products: the Day 2 Convective Outlook and the Mesoscale Discussion, enhancing short-term and next-day severe weather forecasting capabilities.

October 1995: NSSFC Relocated and Rechristened SPC

In October 1995, the National Severe Storms Forecast Center (NSSFC) relocated its operations to Norman, Oklahoma, and was renamed the Storm Prediction Center (SPC).

1998: SPC Began Issuing National Fire Weather Outlook

In 1998, the Storm Prediction Center began issuing the National Fire Weather Outlook to forecast areas susceptible to wildfires based on meteorological factors.

2000: Day 3 Convective Outlook Introduced (Experimental)

In 2000, the Day 3 Convective Outlook was first issued on an experimental basis, similar to the Day 2 forecast, providing longer-range predictions of thunderstorm risk.

2001: Day 3 Convective Outlook Became Official

In 2001, the Day 3 Convective Outlook was made an official product of the Storm Prediction Center after being tested experimentally in 2000.

April 7, 2006: Day 2 High Risk Issued

A Day 2 high risk was issued for April 7, 2006. Day 2 high risks are very uncommon.

2006: SPC Moved to National Weather Center

In 2006, the Storm Prediction Center, National Severe Storms Laboratory, and National Weather Service Norman Forecast Office moved into the newly constructed National Weather Center in Norman, Oklahoma.

March 22, 2007: Day 4-8 Outlook Became Official

On March 22, 2007, the extended forecast for severe weather (Day 4-8 outlook) was incorporated as an official product by the Storm Prediction Center.

April 1, 2009: Responsibility for SPC Products Reassigned

On April 1, 2009, the Storm Prediction Center reassigned responsibilities for issuing the center's products during outages or emergencies to the 15th Operational Weather Squadron based out of Scott Air Force Base.

April 2011: New Graphical Format for Outlooks

In April 2011, the SPC introduced a new graphical format for its categorical and probability outlooks, including shading of risk areas and overlays for population, county, and interstates.

April 14, 2012: Day 2 High Risk Issued

A Day 2 high risk was issued for April 14, 2012. Day 2 high risks are very uncommon.

June 2012: SPC Forecasts General Thunderstorm Risk Areas

As of June 2012, the SPC forecasts general thunderstorm risk areas.

2013: Table Added to Convective Outlook

In 2013, the SPC added a table under the Convective Outlook's risk category map that indicates the total coverage area, estimated population affected, and major cities within a severe weather risk area.

April 21, 2014: Public Comment Requested on Categorical Additions

On April 21, 2014, the Storm Prediction Center began asking for public comment on proposed categorical additions to the Day 1-3 Convective Outlooks.

October 2014: Addition of Marginal and Enhanced Risk Categories

Even after the marginal and enhanced risk categories were added in October 2014, some television stations have continued to use the original three-category system to outline forecasted severe weather risks.

October 22, 2014: Enhanced Risk Category Introduced

On October 22, 2014, the Storm Prediction Center (SPC) introduced an "enhanced risk" category for severe weather, replacing the upper end of the SLGT (slight risk) category. This refinement helped better communicate the potential for impactful severe weather events.

January 28, 2020: Day 1 Outlook Issued with Probabilities

Prior to January 28, 2020, the Day 1 Convective Outlook was the only outlook to issue specific probabilities for tornadoes, hail, or wind. It is the most descriptive and highest accuracy outlook.

March 22, 2022: Day 3 Moderate Risk Issued

A Day 3 moderate risk was issued for March 22, 2022. Day 3 moderate risks are quite rare.

May 2024: Meso-Gamma Mesoscale Discussions

As of May 2024, the Storm Prediction Center has issued 42 meso-gamma mesoscale discussions. Meso-gamma mesoscale discussions are rarely issued by the SPC.