National Weather Service United States Department of Commerce

Winter Storm Shifting From the Central U.S. to the Northeast; Severe Thunderstorms in the South

A winter storm will track to the Lower Mississippi River Valley by Monday and across the central Appalachians Monday night to southern New England by Tuesday. A swath of snow, sleet and freezing rain will spread from the Central Plains east into southern New England by Monday and Tuesday. Severe thunderstorms with damaging winds and tornadoes are possible over the northern Gulf Coast on Monday. Read More >

NCEP 2019 Quarter 4 Newsletter



2019 Aviation Weather Testbed Summer Experiment

The 2019 Aviation Weather Testbed Summer Experiment took place August 19-23 at the Aviation Weather Center in Kansas City, MO. Participants included developers from the Earth System Research Lab, Meteorological Development Lab, and Environmental Modeling Center. Meteorologists from every NWS region including Alaska and Hawaii, Deutscher Wetterdienst (German weather service), Southwest Airlines, NWS headquarters, the US Air Force 557th Weather Wing, and the FAA’s Aviation Weather Research Program also attended. In addition, the FAA’s Aviation Weather Demonstration and Evaluation Services group provided human factors expertise to collect feedback from pilots.


Participants in the 2019 Aviation Weather Testbed Summer Experiment (photo Kristine Berry)


There were three major themes explored during the week. The first was an evaluation of new features and capabilities in the Graphical Forecasts for Aviation and Helicopter Emergency Medical Services web tools.  The second area of focus for the week was evaluating new cloud layer guidance from numerical model 3D cloud information.  Finally, participants looked at potential extended-range convective guidance products. National air traffic planning is increasingly concerned with potential impacts before they start affecting the National Airspace System, and determining the best method to present this information to all stakeholders is critical.





Climate Prediction Center Hosts First Stakeholder Meeting

The Climate Prediction Center (CPC) hosted its first ever stakeholder meeting on 24-26 September 2019 at the NOAA Center for Weather and Climate Prediction (NCWCP).  Approximately 70 core partner participants (in person and remote) attended from the following organizations: NWS WFO/RFC/ROC, DoD (Air Force, Navy, USSOCOM, USACE), FEMA, State Climatologists, National Association of State Energy Officials, AASC, USDA (OCE, Climate Hubs, RMA), NMFS, NOS, OAR, NESDIS,  NOAA RCC, NOAA RCSD, and WSWC).  The focus of the meeting was:

  • Recent performance of CPC operational products
  • New products to be released for the upcoming year
  • New and improved products currently under development
  • Feedback from stakeholders on recent product performance
  • Feedback from stakeholders on their requirements for improved and new products and the products CPC currently has under development

A series of breakout sessions during the meeting provided the opportunity for attendees to provide feedback on CPC’s current suite of products, including how they’re currently used or challenges in using them in the current format and also provide suggestions for potential future needs related to the suite of current CPC prediction and monitoring products.




Hazards Products Break out session during the CPC Stakeholder Meeting. Pictured around the table starting from the left: Melissa Ou (CPC, Mike Halpert (CPC), Jeff Lupo (NWS/SR), Tom Collow (CPC), Campbell Delahoyde (NASEO), Ray Kiess (USAF), William Frey (USAF), John White (USASOC).



8th NCEP Ensemble User Workshop


The 8th NCEP Ensemble User Workshop was held in the auditorium of NOAA Center for Weather and Climate Prediction (NCWCP) at College Park, Maryland. The workshop took place on August 27-29, 2019 with over 200 participants from national and international institutions including NOAA-NWS, NOAA-OAR, NCAR, US Navy, US Air Force, JTWC, ECMWF, UKMet office, ECCC, CMA, CWB, IITM, various universities, and representatives of the private sector.  There were 51 oral presentations, 5 posters and two panel discussions during the three day meeting.


8th NCEP Ensemble User Workshop model development panel discussion (photo Yuejian Zhu)

The workshop brought together experts, stakeholders and users involved in the generation and use of NCEP ensembles, to review progress on the generation and use of operational products since the last ensemble user workshop that was held in June 2016, and to discuss plans for future efforts and collaborations. The main goal of this workshop was to support NWS in its transition from single value deterministic to probabilistic forecasting. The ultimate goal is to convey forecast uncertainty in a user-relevant form. Collaborative efforts on the national (ESPC) and international (NAEFS, NMME) scale were discussed as well.



Florida’s Governor and U.S. Senators travel to National Hurricane Center for Briefings on Hurricane Dorian


As Hurricane Dorian exited the Caribbean Sea and grew into a major hurricane, Florida was placed inside the NHC 5-day track forecast error cone. With difficult decisions looming, several of Florida's elected officials visited NHC to obtain a briefing and to personally thank each member of the NHC and WFO Miami staff for its work and dedication to the mission.

Florida Governor Ron DeSantis stopped by on August 29th, where he was briefed on Dorian's latest track and potential impacts to the state. After visiting with staff, the Governor provided an outdoor press conference to assure Florida residents that the state was ready.  Several days later on Labor Day, and Hurricane Dorian stalled over the northern Bahamas, U.S. Senator Rick Scott (R- FL) came by in the morning, followed by U.S. Senator Marco Rubio (R- FL) that afternoon.  As with Governor DeSantis, each was briefed on Dorian's track, now expected to turn to the north and parallel the Florida coast, but still be close enough to bring tropical-storm-force and potentially hurricane-force winds and storm surge over parts of the Florida east coast.

U.S. Senator Rick Scott (R-FL) speaks with NHC Director Ken Graham (right) and NOAA Communications Officer Dennis Feltgen regarding Hurricane Dorian on Sept. 2, 2019. Photo credit: NOAA Communications


National Hurricane Center provides updates on Hurricane Dorian via Facebook Live

NHC provided 32 Facebook Live broadcasts via its Facebook page during the 11-day span of the media pool for Hurricane Dorians.  The thrice daily broadcasts delivered six million views, with a single peak live view of 456K during the 11:30 a.m. September 1 broadcast when the 185 mph hurricane was close to landfall in the northern Bahamas.

The videos were hosted by NHC Director Ken Graham, providing the latest updates on the storm using the interactive screen at the hurricane briefing desk. Graham also went to the different areas of NHC for a behind-the-scenes look, including TAFB Marine, CARCAH, Storm Surge, TSB, and the Miami WFO.

Due to the large Spanish-speaking population in Puerto Rico and the Virgin Islands, several Spanish-language speakers from NHC TAFB and Miami WFO were brought into the briefings on August 28 and 29 to provide the updates in Spanish. 

Major news agencies, and broadcast and print outlets, monitored the videos for the latest information. The White House sent out a tweet advertising the FB video briefings.


NOAA/NHC Communications Officer Dennis Feltgen shoots a Facebook Live broadcast with NHC Director Ken Graham, August 31, 2019

Photo credit: NOAA Communications



New NOAA-USGS Model Provides Critical Data to Electrical Power Grid Operators


On September 17, NOAA added a new model to its suite of tools designed to help the nation deal with space weather events. The NOAA-U.S. Geological Survey (USGS) Geoelectric Field Model calculates regional electric field levels in the U.S. caused by disturbances in Earth’s magnetic field from geomagnetic storms. The near real-time data indicates the level of space weather impact affecting the electrical power grid to help operators mitigate effects on critical infrastructure.

“We are always looking for ways to improve our forecasts and provide better decision support to our partners,” said Clinton Wallace, director, Space Weather Prediction Center (SWPC), a division of the National Weather Service. “The Geoelectric Field Model will allow us to deliver regional space-weather impact information for the first time. Power grid operators will now be able to quickly understand who in the United States will be affected by space weather, which was a critical missing piece of information.”

In the event of a coronal mass ejection, or CME, directed at Earth, SWPC forecasters will issue a warning using NOAA Space Weather Scales once the CME is detected on satellites stationed at the Lagrange Point One (L1), one million miles from Earth. These measurements at L1 provide key information on how intense the geomagnetic storm is likely to be, but until now, a critical piece of impact information was missing – which parts of the United States will be affected.

The new model delivers graphical maps of the U.S. and gridded data files, updated every minute, that indicate both the strength and direction of the electric fields induced by the geomagnetic storm. Once the geoelectric field is known, the level of geomagnetically induced currents in the power grid can be calculated and the potential impact on the power grid can be assessed.

NOAA-USGS Geoelectric Field Model prototype shows regional geoelectric field levels for a minor geomagnetic storm on Aug. 5, 2019. The new model went operational this week, providing nowcasts of regional geoelectric field levels. The model indicates the level of space weather impact affecting the electrical power grid to help operators mitigate effects on critical infrastructure. Credit: NOAA


The Geoelectric Field Model was developed in close collaboration with the USGS, which provides U.S. magnetometer observations. USGS also transitioned a research magnetic field interpolation model into an operational code that NOAA uses to estimate the magnetic-field time series at locations between the physical observatories. USGS was the principal adviser concerning the solid-Earth conductivity aspect of the calculation.

"This collaboration between NOAA and the USGS has united research projects from the space-science and solid-Earth geophysics communities to provide a practical product of national importance," said Jeffrey Love of the USGS Geomagnetism Program.

NOAA and USGS will upgrade the model in 2020 to incorporate more advanced Earth conductivity models. In addition, NOAA is collaborating with Space Weather Canada to develop a joint U.S. and Canadian version of the Geoelectric field model.



WPC Extends Excessive Rainfall Outlook to 3 Days

As the nation faces increasing extreme rainfall events and increasing vulnerability to flooding, decision makers need sufficient lead time to take mitigating actions. In recognition of this need, and as part of the DOC Agency Priority Goal to mitigate flooding impacts, the Weather Prediction Center endeavored to improve accessibility, accuracy, and lead time of the Excessive Rainfall Outlook. This product provides a national summary of where conditions are favaorable for impactful rainfall, with the risk expressed both probabilistically and categorically (Marginal, Slight, Moderate, and High). “High” risk forecast days have been correlated to events with fatalities and large damages.

Over the past two years, WPC has improved the product display and calibration, tested machine-learning approaches as guidance for the forecasters, added the product to the National Hurricane Center webpage during landfalling tropical cyclones, and executed two educational webinars - reaching over 50 FEMA employees. Through these actions the product now has sufficient skill to allow a change in policy to allow a ‘High’ risk issuance 3 days in advance.

Such lead time is critical. For example, WPC forecast a High Risk of excessive rainfall and warned of catastrophic flooding 3 days in advance of Hurricane Florence. The excessive rainfall outlook was posted prominently on the National Hurricane Center homepage and shared extensively through operational dissemination. This message was repeated and amplified by private sector and media partners. With this amount of lead time, FEMA and States were able to pre-position swift water rescue boats and generators. Catastrophic flooding was observed, and FEMA, State, and local officials were ready to save lives and property.

Check out the latest Excessive Rainfall Outlook at:



View past newsletters at the link below.