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.

OBJECTIVE WEATHER PREDICTION PROJECT (P.Dallavalle)

Short-Range Weather Forecasting Task (P.Dallavalle) - Development of the new MOS-2000 system based on the Aviation (AVN) run of NCEP's Global Spectral Model (GSM) continues. We've now developed MOS equations to predict the maximum/minimum (max/min) temperature, 2-m temperature, and 2-m dew point during the cool season (October - March). Equations have been derived for over 1000 stations in the contiguous U.S., Alaska, Hawaii, and Puerto Rico. Equations are available for both the 0000 and 1200 UTC forecast cycles and for projections out to 72 hours after initial model time. Development and testing of warm season (April - September) temperature and dew point equations is now underway. Similarly, development of both cool and warm season wind forecast equations has been completed for all four forecast cycles, namely, for initial model times of 0000, 0600, 1200, and 1800 UTC. These regression equations will predict the wind speed and wind components (used to obtain wind direction) valid every 3 hours from 6 to 72 hours after initial model time.

Test equations have been developed to predict precipitation type, cloud amount, and ceiling height during the cool season. These equations will be used to produce forecasts for an independent sample taken from the 1998-99 cool season. Verifications of the test forecasts will be presented at the next meeting of the Committee on Analysis and Forecast Techniques Implementation. We've also begun development of MOS equations to predict ceiling height, cloud amount, visibility, and obstructions to vision during the warm season. Finally, our efforts to develop AVN MOS guidance for thunderstorms and severe weather continue. After publication of recent work by Dr. R. Orville, we've modified the algorithm that determines the occurrence of thunderstorms from lightning strike data. This algorithm is used to create our predictand data. We are now computing the predictand monthly relative frequencies which will be used as predictors in the equation development.

Efforts to convert MOS operations to the IBM continue. We are porting operational Cray codes as well as the new MOS-2000 software to the IBM platform. Since the last quarterly report, five more operational Cray codes have been tested and debugged on the IBM and a second library of MOS-2000 software was moved to the IBM, debugged, and compiled. We've also converted the software that produces the MOS guidance based on the Nested Grid Model (NGM) to run on the IBM. We are now using the revised software to produce NGM MOS guidance from two versions of the NGM that are being tested on the IBM. After collecting a month of test forecasts, we will verify the two test versions of the NGM MOS guidance as well as the operational NGM MOS guidance generated from the NGM run on the Cray. This information will be used by NCEP to aid in determining whether the migration of the NGM to the IBM is successful.

Medium-Range Weather Forecasting Task (M. Erickson) - Development of new guidance based on the Medium-Range Forecast (MRF) run of the GSM continues. Experimental MRF MOS equations to predict max/min temperature, 2-m temperature, and 2-m dew point in the cool season were evaluated on independent data for 335 stations. Tests involving predictor and sampling variations as well as model characteristics were conducted. In general, the verification scores showed that the new MRF MOS guidance was as accurate as the operational MRF MOS guidance, with improvements over the current system out to 120 hours. Verification scores of the two MOS systems were comparable for the 132- to 192-h projections after 0000 UTC. All MOS forecasts were more accurate than the direct MRF model output. During the cool season, the MOS guidance provided approximately a 2-day improvement in accuracy at the later projections. For example, the MOS 156-h min (168-h max) temperature forecasts were as accurate as the MRF forecasts of the 108-h min (120-h max) temperature.

Experimental cool season equations were also produced to predict probability of certain categories of precipitation amount. To focus on the heavy precipitation events, we developed equations to predict the probability of the occurrence of 0.01 inches or more of liquid-equivalent precipitation (PoP) independently of the equations to predict the probability of equaling or exceeding 0.10, 0.25, 0.50, 1.00, and 2.00 inches of liquid-equivalent precipitation (PQPF) within the 12-h valid periods. These latter equations, therefore, produce conditional probabilities of precipitation amounts. This technique allows the PQPF equations to focus on differentiating the amount of precipitation which will fall in a given event, whereas the PoP equation is only concerned with predicting the occurrence of precipitation. Unconditional probability forecasts for each PQPF category can be obtained by multiplying the conditional probability by the PoP. Verifications comparing this new technique to the traditional simultaneous approach in which the PoP and PQPF equations are developed together show that the new technique increased the forecast skill in terms of improvement over climate in the Brier score. Although improvements were realized for all amounts, the improvements for the 0.50 and 1.00 inch thresholds were greatest. The new 12-h PoP forecasts were slightly more skillful than the operational MRF MOS PoP forecasts. The final experimental 12-h PoP and PQPF equations have been completed for stations in the continental U.S. and Alaska. Development of the equations for the 24-h periods and for stations in Hawaii is underway.

National Verification Processing Task (V. Dagostaro) - In support of the NWS modernization, we began the process of switching the official source of the public and aviation weather verification data from AFOS to AWIPS for each Weather Forecast Office (WFO) in the conterminous U.S. We provided to each WFO a checklist describing the necessary steps for switching from the AFOS-based to AWIPS-based data collection software. The checklist contained basic instructions, references, and helpful web sites. We assisted the AWIPS System Support Team and NWS Regional Headquarters by providing information about the data collection software. As necessary, we also gave information and advice to the Regional Headquarters to assist them in setting their own policies regarding the software transition. Updated summaries of the transition status were prepared for the Office of Meteorology (OM), and these summaries were posted on a new verification web site. Modifications to a file vital to the transmission of data from AWIPS were coordinated with OSO. Most importantly, we provided feedback to many individual WFOs regarding the receipt and quality of the verification data transmitted from AWIPS. As of December 21, approximately 37% of the WFOs had transmitted verification data from AWIPS, and 8% had ceased running the AFOS-based software.

In support of OM effort to develop a database for public and aviation verification results, we prepared for OM several test files containing max/min temperature and PoP scores. Software modifications were made, as required, to output the scores in an acceptable ASCII format. Some of these test files were also given to Central Region Headquarters to use in evaluating the skill of the local forecasters.

We generated the verification results for the 1999 warm season for max/min temperature, PoP, cloud amount, ceiling height, visibility, and wind speed and direction. Scores were computed for approximately 105 stations in the conterminous U.S. For ceiling and visibility, we prepared and distributed graphs for selected results. In addition, we completed a special study for OM of max/min temperature, PoP, ceiling height, visibility, and wind forecasts. For verification of these elements, we computed scores for approximately 98 conterminous U.S. sites, divided into two regions. Specifically, the two regions consisted of West Coast sites and all other sites. To compute cool season scores, we combined data for October 1997 - March 1998 and October 1998 - February 1999, and for warm season scores, we used data for April 1998 - September 1998 and April 1999 - September 1999.

LOCAL TECHNIQUES DEVELOPMENT PROJECT (S. Smith)

0-3 Hour QPF and Severe Weather Task (D. Kitzmiller) - Operational production of automated Radar Observations (ROB's) based on TDL-developed software was initiated within the Systems Operations Center on November 15, 1999. The ROB's are coded text descriptions of radar echoes within individual WSR-88D umbrellas. They are distributed to internal and external users, and are the basis for the national radar reflectivity contour chart.

Development work continues on national radar reflectivity and vertically-integrated liquid mosaics based on 16-level graphical products from individual WSR-88D sites. In late December, real-time ingest of the necessary radar products began on an occasional basis.

Further investigations have been carried out toward the development of a system for 0-3 hour prediction of conditional severe local storm probability, i.e., the probability of severe local storms given that lightning occurs. We found that the predictors with the most information include the occurrence and areal coverage of 55-dBZ radar echoes, 500-mb wind speed, 700-500 mb temperature lapse rate, and the Total Totals index. This result held true for both warm and cool seasons.

Thunderstorm Identification and Forecasting Task (S. Smith) - The AWIPS SCAN team continued to test SCAN 2.0 in preparation for integration into AWIPS 5.0. Alpha-testing of SCAN 2.0 was initiated at the forecast office in Little Rock, Arkansas. Meetings were held to determine the best way to provide real-time SCAN 2.0 for the Operations Training Branch (OTB) in Norman, Oklahoma. OTB will be developing forecaster training for SCAN as a part of their Warning Decision training.

The AWIPS SCAN/Flash Flood Monitoring and Prediction (FFMP) team continued work in designing the first version of D2D FFMP function for AWIPS Build 5.

Members of SCAN/FFMP team attended the National Hydrologic Basin Delineation meeting in October at the National Severe Storm Laboratory. NSSL has been tasked to develop a national database of small stream basins that will be used by SCAN/FFMP to provide AMBER functionality in AWIPS.

A SCAN briefing was given at the 9^th NSSL/OSF Users Group Meeting in December in Norman. A SCAN team member visited SPC during this trip to learn about SPC Watch issuance procedures.

Local AWIPS MOS Program Task (J. Ghirardelli) - Work continued on developing a "flexigrids" capability for running LAMP on variable resolutions finer than the current 80 km. A comprehensive plan was drafted for testing LAMP performance at higher resolutions. A suitable "warm season" synoptic case was selected--September 29, 1999 at 2000 UTC--and preliminary testing was begun for this case.

The effort to systematically verify LAMP forecasts also continued. Code was developed that will pack LAMP forecast data into TDLPACK format.

Progress was made on Routine Product Updates for LAMP in the AWIPS Build 5.0. QPF was tested in the LAMP job stream on the NHDW system. USA site-specific files were prepared and code changes made for the NWS National Centers. LAMP dynamic memory allocation and flexigrid capability code was tested. Quality control checks of observations in AWIPS for LAMP were developed.

Heavy Precipitation Forecasting Task (J. Charba) - Maintenance and development of the LAMP QPF system continued for the operational AWIPS baseline as well as the national prototype system which provides experimental QPF products through the web to the general public and through NAWIPS to NWS offices.

The QPF graphics made available in these display systems were upgraded by adding additional contours and color shading, which was needed for extreme precipitation events.

The NAWIPS display capability for the QPF products was upgraded, its timeliness and reliability was improved, and it was installed at HPC/NCEP. Discussions were held at HPC on how to provide HPC forecasters with LAMP QPF training.

In preparation for delivery of the LAMP QPF system to the AWIPS contractor for inclusion into Build 5.0, source code and control data files were incorporated into the PCMS file management system.