The primary objective of the Techniques Development Program is to develop analysis and forecast techniques which, when implemented, will help improve forecast accuracy and service to the wide range of users of NWS products. These techniques are implemented on NOAA's computer system, when appropriate, and guidance products disseminated via AFOS, facsimile, or other NWS distribution systems. Techniques are produced for basic weather elements used in public and aviation forecasts, such as temperature and visibility. Also, special emphasis is given to marine-related forecasts and to those forecasts especially associated with mesoscale processes. For many synoptic-scale forecasts, the output of operational numerical models is used to produce forecasts of weather elements of interest to users. When dealing with forecasts of shorter time and space scales, more use is made of data sets rich in information on those scales; for example, hourly and automated surface reports and radar, satellite, and profiler data. For marine-related forecasts, numerical and statistical models relate elements of interest, such as storm surge, to atmospheric analyses and forecasts.

This quarter, progress continued to be made in redeveloping the MOS system and in getting data archives into the TDLPACK format a common format for all archive data for the MOS-2000 system. In this and other conversions to Unix, emphasis is being placed on developing software that will run on large main-frames as well as on workstations. Work is progressing in implementing the first increment of modules of the System for Convection Analysis and Nowcasting (SCAN), which will include the Phase I Thunderstorm Product and the 0-1 h QPF guidance. Implementation of AWIPS was supported through the provision of LAMP and ICWF software and site-specific data for sites using those capabilities; adapting LAMP to a 20-km grid; training field personnel and PRC staff; developing applications for Builds 4 and 5; supporting demonstrations in New York (Popular Sciences's "Best of What's New"), Phoenix, and Kansas City; developing and testing data compression algorithms and software; working toward a unified IFP capability; providing gridded QPF for a risk reduction project; and developing software to support the NOAA Weather Radio from IFP. Several operational and experimental products were added to TDL's homepage: www.nws.noaa.gov/TDL. The AWIPS Applications Development Homepage, which contains the Applications Integration Framework Manual and provides a forum for exchange of ideas, questions, and developmental activities, is accessible from the TDL homepage or www.nws.noaa.gov/TDL/AWIPS.

OBJECTIVE WEATHER PREDICTION PROJECT (P. Dallavalle)

Short-Range Weather Forecasting Task (P. Dallavalle) - Efforts continued at the Cooperative Institute at Pennsylvania State University to develop a methodology to produce MOS forecasts of the max/min temperature, dew point, and wind speed at any point in the contiguous U.S. regardless of the availability of historical observations. MOS forecasts at specific anchor points, climatic normals, and station descriptors are available as potential predictors. Station descriptors include latitude, longitude, elevation, and values representing local effects of urbanization, nearby water bodies, and terrain. The MOS forecasts of the element of interest at a target site comprise the predictand data. In an operational environment, this approach will produce for non-MOS sites appropriately modified forecasts with the characteristics of the MOS guidance at surrounding sites. For the max temperature, experimental results indicate that interpolating the MOS max temperature forecasts from surrounding sites to the target site and then correcting the interpolated value by the climatic difference between the target site and surrounding MOS sites produces guidance that closely resembles the actual MOS guidance. More sophisticated approaches, including the use of other MOS forecasts and interactive variables, appears to add no information. For the min temperature, similar results were obtained; however, the use of a regression correction scheme that considered station descriptors as predictors increased the accuracy somewhat. The regression equation used was valid for the contiguous U.S. Experiments in which equations were developed by stratifying the dependent data according to region or season of the year were made; however, the overall results did not improve significantly. Investigations into the use of other predictors are continuing.

Development and testing of the MOS-2000 software system on the Cray and the HP workstations are continuing. In preparation for development of a complete package of MOS guidance from the Aviation (AVN) run of NCEP's Global Spectral Model, we are accessing NCEP's archives to obtain AVN data for the period of April through mid-July of 1997. These data obtained retrospectively will augment the operational archive. The period of April through September 1997 will provide data for a warm season development of new AVN-based MOS guidance. After examining our archives of hourly data, we are estimating that the new AVN-based MOS system could provide guidance for over 1000 stations in the U.S. A list of potential MOS sites will soon be distributed to the Office of Meteorology and the NWS regional offices. Conversion of our Eta model and Nested Grid Model (NGM) archives to the new MOS-2000 format is also now complete.

A paper entitled "Changes in the National Weather Service's Statistical Forecasting System" by J. P. Dallavalle was completed and presented at the 11th Forecasting Symposium of the Electrical Power Research Institute held in Arlington, Virginia, in November. This paper describes the evolution of the current statistical guidance system and NWS plans for new statistical guidance and methods of forecast preparation.

We have nearly completed development of software to post-process the NGM-based MOS quantitative precipitation (QPF) probabilities for use in a NWS risk reduction exercise to be held in 1998 at the Pittsburgh and Charleston Weather Service Forecast Offices and at the Ohio River Forecast Center. Algorithms coded in the software estimate expected precipitation amounts for 6-, 12-, and 24-h periods from the probabilities valid during the period of 12 to 36 hours after 0000 UTC. The expected amounts are used to determine the fraction of precipitation that will fall in the 6-h periods of 12-18, 18-24, 24-30, and 30-36 hours after 0000 UTC. A Weibull distribution is then fit to the categorical QPF probabilities for the 12-24 and 24-36 h periods. Finally, we've devised a scheme to estimate the 24-h QPF probability distribution from the two 12-h probability distributions contained within the 24-h period. From the probability distribution for the 24-h QPF, we can estimate the probability of precipitation (PoP) as well as the precipitation amount that could be exceeded with a probability of 75, 50, or 25 percent (exceedance fractiles). The software will eventually be implemented in the Interactive Forecast Preparation system so that the local NWS forecasters can obtain guidance for the expected fractions, exceedance fractiles, and the 24-h PoP at gridpoints within the local forecast zones.

Medium-Range Weather Forecasting Task (M. Erickson) - The initial verification of the experimental ensemble-based MOS max/min forecasts was completed. This verification included forecasts issued between October 1, 1996, and December 31, 1996, for over 200 stations. We compared the accuracy (in terms of the mean absolute error) of the MOS guidance based on the operational Medium-Range Forecast (MRF) model to the consensus ensemble-based MOS forecasts. By the 120-h projection, the consensus forecasts were more accurate than the operational forecasts. Furthermore, the 180-h consensus temperature forecasts were as accurate as 168-h operational forecasts. We also evaluated the percent of max/min observations which fell within the range of the MOS ensemble forecasts. At best, only 45% of the verifying observations fell within the forecast range. The usefulness of the range and standard deviation of the ensemble forecasts will be explored further. These results were presented by J. Settelmaier at the National Weather Association's 22nd Annual Meeting held in Reno, Nevada, in October.

A new, extended archive of the MRF model was established in September, and we are now accessing NCEP's MRF history tapes to obtain a complete warm season archive. The data from August and the first half of September were retrieved from tape and placed in TDL format. We are currently working on recovering the April through July data. When this effort is completed, the data will be used in redeveloping the medium-range forecast guidance.

National Verification Processing Task (V. Dagostaro): In support of the AFOS-Era Verification (AEV) program, we continued our efforts to convert the data processing system to run on UNIX-based platforms. Experiments were conducted to ensure that a direct-access data file created on the Cray mainframe and transported to a local workstation is usable by the local workstation software, and vice versa. Initial results indicate that certain types of files created on the Cray mainframe and HP workstations differ slightly in format, but the integrity of the data is unaffected.

Due to field testing of the AFOS-based data collection software at spin-up offices, data for certain AEV sites have recently been transmitted from pairs of NWS offices, namely, the office responsible for the official forecasts and a spin-up office running the AEV software in practice mode. When such duplicate data were re ceived, the official data were sometimes rejected, depending on the time of receipt of the data. In these cases, the unofficial forecasts from the spin-up offices were collected and stored in the central AEV data archive. Software has been written to retrieve the official data, as needed, and remove the erroneous data in the central data archive. Testing of the software is now underway. Development of software to save recent AEV data in the new MOS-2000 format continues.

Severe Weather Prediction Task (R. Reap): Software has been written to decode archived data from the National Lightning Detection Network. Reports of lightning activity for the period of April 1, 1994, through September 30, 1997, were obtained from NASA archives at the Marshall Space Flight Center. The data are intended for use in development of MOS forecast equations to predict thunderstorms and severe local storms. The lightning reports contain the time of occurrence, location (latitude and longitude), polarity, signal strength, and number of strokes per flash for individual cloud-to-ground lightning flashes over the conterminous U.S.

To use the lightning data as predictands in the MOS development system, a new program (U523) was written to convert the lightning reports to the standard MOS-2000 format. U523 will convert all available thunderstorm observations (lightning reports as well as severe local storm reports) to this format. Thus, cloud-to-ground lightning reports, tornado occurrence and estimated Fujita-scale values, hail occurrence and hail size, and damaging wind occurrence and maximum wind speeds are processed as predictands for MOS development. The various reports are summed over specific time periods (for example, for an hour) for grid blocks designated by the user in the U523 driver program.

LOCAL TECHNIQUES DEVELOPMENT PROJECT (R. Reap)

0-3 Hour QPF and Severe Weather Task (D. Kitzmiller): Work was started on the task to rehost the national radar mosaic. A prototype system was established for ingesting Radar Coded Messages (RCM's), along with infrared satellite observations, lightning reports, and humidity data from numerical models. The prototype system is now producing radar mosaics with added quality-control features to eliminate echoes due to ground clutter and anomalous propagation.

An expanded dataset for the development of the 0-3 hour QPF algorithm was generated. The dataset contains collated radar and satellite observations, numerical model output, and Stage III rainfall estimates for both the 1996 and 1997 warm seasons. We are currently using the data to generate probability forecast equations for three starting times. Candidate predictors for the equations include interactive predictors based on radar and satellite observations.

Work continued on implementing the 0-1 hour QPF and severe local storm nowcast algorithms in AWIPS Build 4.1. Test displays of the gridded QPF fields were successfully produced. An effort to verify the reliability of the probability algorithms was started by obtaining a large sample of WSR-88D Archive Level II tapes covering convective weather cases from the 1996 and 1997 warm seasons.

Thunderstorm Identification and Forecasting Task (S. Smith): SCAN briefings were given at the Cooperative Institute for Research in the Atmosphere and the Regional and Mesoscale Meteorology Branch of NESDIS, the National Severe Storms Laboratory, and the National QPE Workshop. SCAN activities were also briefed at the Fall Meeting of the NWS Directors.

Two new SCAN efforts were initiated. The first involves development of an automated thunderstorm anvil tracking algorithm. NSSL is taking the lead in this, but will work with NESDIS to verify the algorithm. The second is the implementation of NEDSIS' automated precipitation estimator into the flash flood component of SCAN.

An AWIPS Design review of version 1.0 of SCAN was held. The two main components of SCAN 1.0 are the Phase-I Thunderstorm Product and the 0-1 hour QPF. A graphical user interface was developed to allow the forecasters to adjust the D2D display of the radaridentified cells in real time. Verification of the Phase-I and Phase-II Thunderstorm Products based on data from 1997 convective season was initiated. Work continued on the implementation of the Phase-I product into Build 4.1 of AWIPS. This included modifications to the radar product ingest and the lightning association routine. A few minor changes were also made to the decision tree.

Local AWIPS MOS Program Task (J. Ghirardelli): We continued to assist the Network Control Facility (NCF) in monitoring the local LAMP systems, which are currently run within AWIPS 2.1 at WFO's in Pleasant Hill, Missouri; Tulsa, Oklahoma; and Wichita, Kansas. As part of this effort, a training session was held to educate the NCF staff on the characteristics and operation of the LAMP system. LAMP was also modified to run forecasts on TDL's GDP systems for the Wichita area. This will facilitate testing of the local LAMP systems, since we can now more closely compare forecasts for the same region that are run on two different systems. LAMP site-specific files were created and delivered to PRC for 10 additional AWIPS sites. We also made an extensive investigation of the locally decoded observations used in LAMP at the WFO's and found errors in the code that were addressed by filing a Discrepancy Report.

Additions to TDL's Home Page on the Internet were also developed such that users will be able to see graphical displays for a number of analyzed fields produced by the LAMP model. Furthermore, a list of stations will be available for users to view real-time text forecasts for the stations they select. LAMP forecasts on the home page are automatically updated every three hours. The LAMP additions to the home page are presently scheduled for implementation in mid-January.

Progress continued in the effort to adapt LAMP to a 20-km grid with the modification of the CLAM and SLYH models. Enhancements to LAMP AWIPS scripts were also begun to better handle the variation in data arrival times. This effort will make LAMP more robust in handling delayed reception of ingest data.

Heavy Precipitation Forecasting Task (J. Charba): Work continues on developing applications software to display realtime products from the LAMP QPF model at NWS field offices. An effort was also undertaken to incorporate the realtime LAMP QPF products on TDL's Internet Home Page. Implementation of the products on the Home Page is expected by mid-January. A manuscript titled, "The LAMP QPF Products. Part I: Model Development," documenting the model development and forecast products was submitted for publication in Weather and Forecasting. In addition, further revisions were made to the draft Storm Survey Report on the February 1996 Pacific Northwest Floods.

In anticipation of future developmental needs, the full archive of hourly precipitation data available at NCDC (1940-1995) was ordered and received. Attempts to process these data were postponed, however, after discovering that the new software to decode the precipitation data needed further testing.

MARINE ENVIRONMENTAL PREDICTION PROJECT (W. Shaffer)

Hurricane Storm Surge Forecasting Task (W. Shaffer): We are continuing to adapt the SLOSH display program to AWIPS. This program will use TCL/TK graphics which allows us to run the same code on both the UNIX platform and on PC's under Windows. The Mississippi Gulf Coast Slosh basin is virtually complete, with finishing touches being put on the barrier heights and the channelized 1-dimensional flow. This basin will be turned over to NHC so they can begin a simulation study for evacuation planning purposes.

We are investigating the SLOSH hurricane wind model, with the goal of improving surface winds, and thus the surge forecasts. We find that the maximum wind from SLOSH can be expressed explicitly as (approximately) proportional to the square root of the radius of maximum wind. This simplification may aid outside modelers in adapting the SLOSH hurricane wind field for their use.

Extratropical Storm Surge Forecasting Task (W. Shaffer): We continue to work on a West Coast version of our extratropical storm surge model, with the input winds taken from the AVN model. We are at the point of running this model in a semi-operational mode.

Coastal Wave Forecasting Task (C-S. Wu): We compared two parametric ocean wave model's computations against observations from hurricane Fran (1996) and found the more recent model gave better results. Next, we examined the model's sensitivity to various meteorological input parameters. The wave period was found to vary little with changes to hurricane parameters, but the wave height is strongly affected by the hurricane's intensity. We programmed the two models into in the interactive program and are checking it with other hurricane cases.

We prepared the offshore bathymetry in the area of Topsail Beach, North Carolina, for a test of wave refraction using predicted hurricane waves as input. The growth of wind waves in shallow water is under investigation. We evaluated two breaking wave models and modified the Random Breaking Wave (RBW) version to include wave set-up and wave run-up. We continue to verify the results from the RBW model with experimental data.

LOCAL PRODUCTS DEVELOPMENT PROJECT (D. Ruth)

WFO Application Development and Support Task (D. Ruth): Design, Development, and Testing teams worked to code and test hydrometeorological (HM) applications for AWIPS Build 4. One team is developing formatters for the Hourly Weather Roundup and Climate Report to be broadcast on the NWR, an application to monitor Terminal Aerodrome Forecasts (TAFs), and forecast verification software. A second team is writing depictables that display thunderstorm information and MOS, LAMP, and ICWF forecast data within the AWIPS D2D window. Design reviews were conducted for each of these applications. FSL participated in reviews for new depictables via video teleconference.

IFP Implementation and Enhancement Task (R. Meiggs): TDL supported PRC in the software and system integration testing of AWIPS 3.1. This included identifying, fixing, and verifying Discrepancy Reports (DRs). In addition, release notes were prepared for the beta release of AWIPS 3.1 to Tulsa in mid-December.

ICWF and LAMP site-specific files were delivered to PRC this fall. This set contained the first cluster plus those sites already deployed. These data will support the selective use of ICWF at any AWIPS WFO. An ICWF Selective Use User's Guide has been completed in association with AWIPS 3.1. In addition, the Interactive Computer Worded Forecast User's Guide was updated to document changes between AWIPS 2.1 and 3.1.

Additional training was provided to the Network Control Facility (NCF). Sessions were focused on data streams required for proper initialization of the ICWF and changes between AWIPS 2.1 and AWIPS 3.1 in the areas of directory structure, data flows, and other system level information. There have been several conference calls with the risk reduction sites to discuss bug fixes and enhancements.

Coding continued in support of watch decentralization and regional warning formats. Decoders for the SAW and SEV messages have been completed for testing at TDL. These messages provide initial information necessary for issuance of severe thunderstorm or tornado watches by the WFO.

Several of the support programs necessary for the automated production of Service Area Forecasts (SAFs) are now complete. Detailed design and coding of the SAF formatter is underway. We have added flexible period lengths in the Zone Forecast Product and heat/wind chill indices to the Revised Digital Forecast product.

During this quarter, TDL worked with the Ohio RFC to test the transmission of gridded QPFs prepared at the WFO in Charleston, West Virginia. This testing has resulted in minor modifications to the ICWF software which are being incorporated into AWIPS 3.1.

IFP Product Development and Evolution Task (M. Peroutka): The first meeting of the IFPS Forecasters Working Group (IFWG) was held in Silver Spring in early November. Representatives attended from almost all NWS Regions as well as FSL, NCEP, and OM. The primary focus was developing a baseline understanding of IFPS among the membership.

Coordination continued with FSL developers on the design of the Common Database Server (CDS) which will support the consolidated IFPS. Work also continued to adapt the ICWF database access library to use the CDS. Related development of library routines which track the transformation of data through the system continued as well. Once these infrastructure tasks are complete, the various applications will be modified to work within the IFPS framework. A draft copy of the IFPS Development Plan was delivered to cooperating offices for review and comment.

Developers prepared workstations, traveled to New York, and provided demonstrations of IFP techniques at the Popular Science "Best of What's New" exhibit. A workstation was also prepared and shipped to Pleasant Hill, Missouri, to provide similar demonstrations for Central Region personnel. Finally, a pair of workstations was prepared to provide demonstrations at the 78th Annual Meeting of the American Meteorological Society in Phoenix.

Software was developed which permitted the transfer of GRIB-encoded grid forecasts from a WFO to a server. This will support the first operational tests of the Graphical Forecast Viewer. Forecasters at the Charleston, West Virginia, and Norman, Oklahoma, Forecast Offices will generate the grids and post them to a server in Silver Spring. Web-capable users can access these gridded forecasts from anywhere on the World Wide Web.

IFP Interpretation and Editing Task (D. Ruth): Probabilistic QPF software developed at the University of Virginia (UVA) was transferred to TDL for integration and testing. This prototype system will be deployed at forecast offices in Charleston, West Virginia, and Pittsburgh, Pennsylvania, for evaluation over the next 2 years.

A design review was conducted for the initial implementation of intersite forecast coordination within IFPS. This is accomplished via the exchange of Digital Forecast Matrices (DFMs) between offices on the AWIPS Wide Area Network. The capability is to be included in a Build 4 release of ICWF.

The development of an interface that enables forecasters interactively to direct digital and worded public zone forecasts to NWR towers is nearly complete. This component, along with Service Area Forecast formatters, will be tested at the forecast office in Charleston this winter.

The capability to blend forecast model output interactively was added to the ICWF slider bar server. This feature will be highlighted during demonstrations at the January AMS meeting in Phoenix, Arizona.

Field Applications Assistance Task (R. Beasley): Modifications were made to the TAF decoding software (TAFDEC) and the aviation monitoring program (MONITR) to address field trouble reports. Additionally, a new program, TAFQC, was released to all field sites in November and subsequently modified to address field trouble reports. This software provides the capability to check TAF formats prior to their issuance. TAFs can also still be checked after issuance and both collectively and individually.

The ASOS quality control comparison program (ASOSCOMP) was released to all field sites in November. Documentation was provided via CCMAIL. In addition, TDL continued to provide support to OSO14 for the production of the daily ASOS QC reports.