MDSS Lab Prototype: Program Update and Highlights Bill Mahoney National Center For Atmospheric Research (NCAR) MDSS Stakeholder Meeting Boulder, CO 20 October 2005 Photo by Dave Parsons

2 Overview Overall System Enhancements Colorado Routes System Configuration New Products Challenges Release-4.0

3 System Enhancements for Field Demo Added Bridge Frost Potential Product –Based on Iowa State University Model (Tina Greenfield) Added snow-water ratio algorithm Added CDOT & E-470 ESS data (via MADIS) Refined Rules of Practice for E-470 and CDOT Refined insolation data sources (model blend)

4 Colorado Routes West Denver South Denver Vail Pass 300 forecast site

5 MDSS Configuration – Colorado Supplemental Weather Models Ensemble System ModelInitialization MM5NAM (Eta) WRFNAM (Eta) National Weather Service Data Eta ModelAVN MOS GFS ModelSYNOP METARS DOT Data RWIS Data Ingest Forecast Module A Forecast Module B Forecast Module C Forecast Module D Forecast Module N Forecast Integrator Post Processor Forecast Product Data Fusion - Road Weather Forecast System DICast TM Road Condition & Treatment Module - Road Temperature Prediction Model - Chemical Concentration Algorithms - Rules of Practice for Anti- and Deicing Rapid Update Cycle (RUC) Multiple Members Plow route specific treatment recommendations

6 Supplemental Weather Forecast Model Domain 4 April hr forecast valid 3 pm 5 April 2005.

7 MM5 and WRF Models Time Lagged Ensemble Used MM5 – Latest MM5 – Run from 1 hour previous MM5 – Run from 2 hours previous WRF – Latest WRF – Run from 1 hour previous WRF – Run from 2 hours previous FSL Model System Configuration WRF output 9 November 2004

8 Intense direct solar radiation effects Diurnal temperature variations Strong nocturnal inversions Shallow cold fronts Large spread in model precipitation forecasts Rain-to-Snow transition MDSS Colorado Challenges

9 Strong Diurnal Temperature Swings 43 o F at 7 AM 83 o F at 11 AM Challenge for air and pavement prediction

10 Strong Nocturnal Inversions Surface Temperature = 45 o F Temperature at 1000 ft AGL = 60 o F All models have great difficulty with shallow layers! Impacts: Road frost Fog Road Temperatures

11 Early Morning Fog Case 14 November 2004 Low clouds and fog observed Clear skies in WRF model

12 Shallow Upslope Case Shallow upslope clouds Model estimation of clouds

13 Mountain Wave Clouds WRF Model Satellite Image WRF was able to predict some wave clouds, which is important for Front Range Wave Clouds

14 Weather models smooth out terrain details resulting in poor forecasts at peaks and valleys. Resolving Complex Terrain

15 Resolving Complex Terrain Standard NWS models cannot resolve details of the rugged terrain. T254 ~30 mile grid resolution T170 ~60 mile grid resolution WRF Terrain ~6 mile grid WRF Model Terrain 12-km Grid Black Hills Big Horns Teton San Juan Central Rockies

16 Halloween Snow Event Case Model Differences WRF Model MM5 Model

17 MDSS Release-4.0 Expected to be last major Lab MDSS Release! Release available mid fall 2005 Major refinements to Rules Practice Minor refinements to road temperature model (SNTHERM-RT) Route by route configuration Add reasons for recommended treatment Add additional chemical equations (Caliber, IceBan) Add blowing snow effect on treatments Refine black ice (refreeze) treatment logic Add ability to mix chemical types (user defined treatments) Refine display products as necessary Release-4: Fall 2005