Forecasting Storm Tracks Before Formation and Wind Speed per Platform Scott Morris Earth Science Associates Long Beach, CA November 5, 2015 User Conference 11/05/15

Last Year Discussed impact of hurricanes on oil and gas production in the GOM Overview of the data available from the NHC Outlined workflow for combining NHC data with GOM 3 –Primarily limited to tables and pdf files of maps This Year Added data directly to GOM 3 and GOMsmart Developed and implemented new methodology to forecast storms earlier than the NHC

Data Available From the NHC 1. Disturbances. These are the precursors to cyclones 2. Forecast Track. The estimated future track of the cyclone. REPEAT...CENTER LOCATED NEAR 23.0N 74.4W AT 01/2100Z AT 01/1800Z CENTER WAS LOCATED NEAR 23.0N 74.2W FORECAST VALID 02/0600Z 23.2N 74.7W MAX WIND 120 KT...GUSTS 145 KT. 64 KT... 40NE 40SE 30SW 30NW. 50 KT... 60NE 70SE 40SW 60NW. 34 KT...120NE 150SE 100SW 90NW. 3. Wind Radii. The strength of the winds in different directions. User Conference 11/05/15

GOMsmart User Conference 11/05/15

GOM 3 User Conference 11/05/15

Wind Speed Charts Extent of 50 Knot winds in south west quadrant Extent of 34 Knot winds in south west quadrant Between 34 and 50 knot winds User Conference 11/05/15 Between 50 and 64 knot winds Between 64 knots and the max wind speed

Forecasting Using Disturbances Developed a new technique –Began with students from California State University, Fullerton –Refinement continues to be made by ESA Uses the NHC disturbed air polygon files (shapefiles began being released in 2015). –Since the data is so new, nobody else has developed a similar algorithm. This method is not meant to replace the track from the National Hurricane Center (NHC). The algorithm produces a track earlier than the NHC so can be used as an advanced warning system. User Conference 11/05/15

The General Idea Use past tracks (analogs) to make the forecast. User Conference 11/05/15 Find analogs that are: 1.Near the disturbance 2.Heading in the same direction as the disturbance 3.Follow a path similar to the disturbance

User Conference 11/05/15 Methodology 1. Near the disturbance 1,224 miles 480 miles

User Conference 11/05/15 Methodology 2. Heading in the same direction as the disturbance 325° 316°

User Conference 11/05/15 Methodology 3. Following a path similar to the disturbance

User Conference 11/05/15 Methodology 3. Following a path similar to the disturbance 86 mi. 72 mi. 52 mi. 38 mi. 33% 27% 22% 18%

Methodology 3. Calculate a dissimilarity (G) score. Repeat for every valid point. Chose the minimum G User Conference 11/05/15

Methodology Repeat for every analog User Conference 11/05/15

Translate all analogs to the centroid of the origin polygon. Methodology User Conference 11/05/15

< – – 1.5 Weights (%) > 1.5 The largest weight is 3.2%. The top 10 analogs make up 24% of the total weight. Methodology 6. Translate all analogs to the centroid of the origin polygon. User Conference 11/05/15

Methodology 7. Use the weights to find the weighted average of the Latitude and Longitude values of the analogs. User Conference 11/05/15

Confidence Intervals 33% of the total weight lies between Together this makes a 66% confidence interval User Conference 11/05/15

Bill Forecasts Over Time June 12 6:00 p.m. Forecast Track Confidence Interval Path to Centroid NHC Forecast Disturbance 0% - 40% Origin Polygon Formation Chance 40% - 60% 60% - 100% June 13 5:00 a.m. June 13 12:00 p.m.June 13 6:00 p.m. June 14 6:00 a.m. June 14 6:00 p.m. June 15 3:00 a.m. June 15 9:00 a.m. June 15 3:00 p.m. June 15 6:00 p.m. 24 Hour Forecast Translation Error Total Forecast Error User Conference 11/05/15 Error For Bill

Hours Before NHC Forecast Error (miles) 24 Hour Error48 Hour Error72 Hour Error96 Hour Error 120 Hour Error 2014 CLIPER5 Mean Error 24h = 134 mi 48h = 279 mi 72h = 432 mi 96h = 547 mi 120h = 693 mi Type of Error = Forecast = Translation User Conference 11/05/15

Overview ESA formatted data from the NHC is directly available in GOM 3 and GOMsmart Wind radii data from NHC turned into shapes and data is interpolated to create plots of wind speed over time New technique to make a forecast before the NHC using the new disturbance data –Good initial results but needs more data to properly validate