Forecaster Thoughts – Tom Ainsworth (2009 Week 2)

Overview:

During the week of May 4-8, I had the privilege of visiting for the first time the National Weather Center (NWC) in Norman, OK. The purpose of my trip was to participate as an evaluator in NWC’s Hazardous Weather Test Bed 2009 spring “Experimental Warning Program” (EWP). EWP is designed to “test and evaluate new applications, techniques, and products to support WFO severe convective weather warning operations.” While Alaska, and especially Juneau, may not be known for severe convective weather, the opportunity to participate in EWP was valuable in several ways. First, I was able to evaluate emerging weather forecasting techniques and technologies that may have potential application in our data-sparse region. Second, I was able to network with a variety of people from around the nation working in both academia and government. Ensuing discussions covered ongoing field activities in different NWS regions and led to thoughtful brainstorming about future NWS services. And third, I accepted the offer to deliver a brown bag seminar on the last day of class. My brief talk was designed to raise awareness about science-service issues in Alaska. I concluded the talk by offering a friendly challenge to EWP to develop “new applications, techniques, and products” for Alaska Region WFOs which rely less on radar and more on other types of remote sensing.

1. Evaluating Emerging Technologies:

This year’s EWP focused on evaluating four potential WFO applications: 1) multi-radar/multi-sensor gridded severe weather algorithm products; 2) three-dimensional Lightning Mapping Arrays; 3) CASA (Center for Collaborative Adaptive Sensing of the Atmosphere) low power/short range radars; and 4) the Phased-Array Radar (PAR) operating in Norman.

The multi-radar/multi-sensor gridded algorithm products were made available via the Warning Decision Support System – Integrated Information (WDSS-II) developed at the National Severe Storms Laboratory (NSSL). Data from multiple radars and three-dimensional numerical model (RUC) temperature analysis grids produce more vertical volume samples than a single 88D can alone. Refresh rates are as quick as one to two minutes. Overlapping coverage fills gaps from terrain blocking. There are three WDSS-II domains across the south and mid-Atlantic states and a fourth “floater” domain that can be moved to an area expecting severe weather. Among the grids produced are echo tops above selected dBZ reflectivity cores or certain temperatures, lightning density, azimuthal shear, rotation tracks of the highest observed cyclonic shear, Maximum Expected Size of Hail, and vertically integrated Lightning Mapping Arrays (LMA) detecting source points of total lightning in 3D.

LMAs detect VHF radiation emitted as lightning propagates. Unlike the existing National Lightning Detection Network (and Canadian Network utilized in SE Alaska), LMAs detect both in-cloud and cloud-to-ground lightning. Emerging research is identifying a link between increased lighting activity, intensifying storms, and severe microbursts. Each of these parameters is plotted over a Google Earth background and trends of each parameter can be tracked for individual thunderstorm clusters using a multi-scale graph display.

CASA radar output can reveal storm structure, especially in the lower atmosphere, with much higher spatial and temporal resolution than the 88D, especially if the CASA radar is situated at a distance from the 88D. In fact, the rapid update cycle (~60 seconds) and short CASA radar range (~40 km) was difficult at first to get used to. PAR data sets have the range of the 88D and the higher resolution of CASA technologies. PAR is “electronically steered” S-Band radar that provides “targeted” scanning within a 90-degree azimuth sector. Its storm scanning strategy is significantly faster than the 88D which greatly enhances the operator’s situational awareness of storm trends. The PAR may one day replace the aging 88D network.

In summary, participating in the EWP was easily the most intensive, hands-on exposure to new radar technologies I have had since I attended the 88D Operations Training in Norman 15 years ago. All of the tools and applications I tested have significant potential for improving very short term forecast decision making. Assessing each application is literally the stuff of PhD dissertations. Unfortunately for Alaska WFOs, applicability of most of these technologies in the foreseeable future will be negated by the lack of requisite archive Level 2 data, no over-lapping radar coverage areas, the sparsity of conventional surface based data sets and the resultant impact on RUC-II model analysis. EWP facilitators requested field offices submit case studies and Level 2 archive data to which the tools can be applied. Unfortunately, the FAA does not maintain Level 2 data from any of the Alaska 88Ds. PAR and CASA radars, in my opinion, have the highest potential for use in Alaska Region.

2. Professional Networking:

It was quickly apparent to me the NWC is an important and very active facility for NOAA. It symbolizes the advantageous partnerships between university training, applied research, and NWS operations. The EWP work space was literally surrounded by the Norman Forecast Office, NSSL, and the Storm Prediction Center (SPC). During the week I was at NWC, a major tornado field research project covering the Great Plains over five weeks (VORTEX-2) was kicking off with international media attention. Precise orchestration of people and events in NWC this week – including several public tours per day – was managed by University and NOAA public affairs personnel. I was able to meet up with two OU graduate students with connections to WFO Juneau: one was hired in 2007 as a STEP; the other was hired as a SCEP this year.

My co-evaluators in EWP this week represented an equally diverse group: a Lead Forecaster from Chicago; a General Forecaster from Seattle; and a PhD candidate from Florida State University. Each person brought a different set of skills and experience to the program. Discussions during breaks and after hours generally drifted to future weather forecasting operations and trends of university research activities. I learned from conversations during the week that there are a number of different interpretations of the concept “decision support services”. DSS is a term becoming commonly associated with NWS Strategic Planning, and is a major agenda item in the National MIC/HIC Meeting later this year. My sense is field offices would benefit from having a clear and consistent definition of what NWS upper management means by DSS.

3. Brown Bag Seminar:

NWC routinely offers brown bag seminars by OU faculty and NOAA/NWS staff. Visiting scientists are also offered the opportunity to present short seminars. In the case of EWP, visiting evaluators are able to give a short presentation during the weekly de-briefing session on Friday. I agreed to speak about science and service issues in Southeast Alaska and demonstrate what makes warning decision making in our region particularly challenging. The presentation highlighted our large AOR, complex terrain, sparsity of in-situ data (including radar), and the value of high resolution satellite data to warning decision making. In closing, I requested the Hazardous Weather Test Bed (HWT) audience to consider ways they could apply their mission to develop “new applications, techniques, and products” for WFOs in Alaska Region and elsewhere that may rely less on radar and more on other types of remote sensing. In response, I learned the HWT intends to hire a student next fiscal year to begin investigating and developing warning decision applications related to satellite imagery. My presentation slides are available on the regional network (R:/) in the “Juneau” folder (HWT-NWC SEAK ScienceService 2009-05.ppt).

Summary:

I am very grateful to have had the opportunity to travel to the NWC May 4-8 and participate as an evaluator in this year’s Experimental Warning Program. The EWP cadre knew their material thoroughly, was well prepared, and interacted well with visiting evaluators. The amount of new material presented was considerable but, over time, was manageable. The NWC is a very busy place with OU faculty and students, NOAA researchers, and NWS NCEP and WFO operational staff. The interaction with these groups and fellow evaluators during the week was professionally stimulating. And even though there are serious road blocks to using the new technologies anytime soon in Alaska Region, the staff there was open to hearing objective, constructive feedback. I recommend supporting any future opportunities for Alaska Region field office personnel to visit and experience NWC.

Tom Ainsworth (NWS Juneau AK – 2009 Week 2 Evaluator)

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