1. FAA Tactical Weather Forecasting In The
United States National Airspace
Bill Dupree
Marilyn Wolfson
Rick Johnson, Jr.
Bob Boldi
Evelyn Mann
Kim Theriault Calden
Carol Wilson
Paul Bieringer
Brian Martin
Haig Iskenderian

2. Aviation Delay Problem
Aviation Weather Delays
US Air Traffic Density
Forecast Requirements
$200 M CIWS
2B/yr total delays
See Jim Evans talk
Reduce Delay
Increase Capacity
Keep routes open longer
Anticipate reroutes
Reduce ground delay
Improve approach management
Situational awareness
Improve Safety
Increase airport capacity to meet projected demand
Make air traffic flow over land & sea more efficient
Increase or improve airspace capacity in the 8 major metro areas & corridors that most affect total system delay
Increase on-time performance of scheduled carriers
Improved flight during severe en-route wx conditions
Improved flight during unfavorable airport wx
Reduce commercial airline fatal accident rate
Reduce the number of fatal accidents in GA
Reduce cabin injuries caused by turbulence
Accurate Wx and Forecasts
Current
Rapid Update (2-5min)
High-resolution (1km)
Reliable

3. Motivation for Precip Forecast (Terminal Delays)
04:00 Z
03:30- 5:10 Z
10:30-12:10am Local Time
forecasts claimed line would remain North of Airport.
22 planes missed sort 2 million/plane
44 million in losses
Here is a snapshot of the wx and the Memphis tracon at 11PM. The red tracks are arrivals and the black tracks are either fly-overs or tracks that we’re not sure of. As you can see the wx is still to the north of the runways and the planes are landing successfully.
Unfortunately, this is a snapshot at midnight and as you can see the wx is just about on the runways and there are microbursts and gustfronts associated with the convection.
Now I’ll roll the movie and let it loop twice. As you can see right after midnight most of the planes that were trying to land couldn’t and had to divert to southern airports because they were low on gas. Even if the refueled and tried to go around the line and land from the north they would have missed the package sort. Unfortunately this episode cost the parcel carrier millions of $ since they had to deliver all the next day packages for free.
Memphis, TN 15 July 1997
Vertical Integrated Liquid Water (VIL)

4. Motivation for Echo Tops Forecast (En Route Delays)
VIL (levels)
Echo Tops (kft)
Flights Shown: All flights at or above 4.9 km (16,000 ft)

5. Overview Problem 0-2 Hour Weather Forecast System Research Efforts
Evolution of Forecast System
Forecast Components
Forecast Products
Performance
Research Efforts

6. Evolution of the Forecast System
1998:
1-hr Forecast
in ITWS
1999:
Growth/Decay
Tracker Patent
2002:
2-hr Forecast
(Multi-scale Tracking &
Weather Classification)
2003:
Growth/Decay
Trending
2003:
Winter
Forecast
2005:
Echo Tops
Forecast
2005:
Satellite/Precip
Loop
Integrated
Terminal Weather
System (ITWS)
Corridor Integrated Weather System (CIWS)
New York
Orlando
Memphis
Dallas
NEXRAD
ASR-9 Radars
Canadian Radars

7. Weather Classification
NEXRAD Precipitation (VIL)
Weather Classification
9 July 2003
17:17 Z
Line
Storms
Small
Cells
Large
Cells
Stratiform
Rain
Multi-scale
Tracking
Forecast
Engine

8. Multi-scale Tracking Technology Weather Classification
Envelope
Envelope Vectors
VIL
9 July 2003
Weather Classification
Image
13 x 69 km
Multi-scale
Tracking
Vectors
Cell
Cell Vectors
13 km

9. Growth and Decay Trends
Difference Images
(Each Advected to Analysis Time)
Trend Images
VIL & Echo Top Images
Prior Image
Current Image
Growth/Decay
Boundary Growth
Apply match template kernels to each pixel
VIL

10. Generation of 2-hr Forecast
Weather
Classification
Multi-scale
Tracking
Growth & Decay
Trends
Boundary
Growth
Echo Top
Cap
VIL Forecasts
Thunderstorm Evolution Models
Echo Top
Forecasts

11. VIL Forecast Verification 60min (25 June – 1 July 2005)
Hit
Miss
False Alarm
Loop twice: One week of data not just an isolated case. Point out how good performance. How it cycles from 16-17Z. Coupling of Miss and FA for airmass. Still useful for air traffic.
Note Convective Initiation: ETF even better performance.

12. Overview
Problem
0-2 Hour Weather Forecast System
Research Efforts

13. Convective Initiation Forecasting (Front and Wind Boundary Locations)
DATA SOURCES
Doppler Radar
Surface Sensors
Model Winds
Surface
Wind
Analysis
System
Temporal
Integration
Filters
Automated
Front/Boundary
Detections
“Low Altitude wind shear” Space Time Mesoscale Analysis System (STMAS). Currently uses the largest analysis domain
Utilizes largest surface observational database (no radar data)
5 km horizontal resolution only at the surface
15 minute update rate, ~45 minute product latency
Corridor Boundary Layer Wind Analysis System (CBOUND)
Utilizes Doppler radar and surface observations
1 km horizontal resolution, ~250 m vertical resolution in BL
5 minute update rate and 5 minute product latency
New convection often develops in areas where fronts and wind boundaries are present

14. Automated Front Detection
20 April 2005
(10-5 sec-1)
Data from NOAA FSL: Space Time Mesoscale Analysis System (STMAS)

15. Summary Demonstrating 0-2 hr forecasts of VIL and Echo Tops
Covers busiest air traffic sectors of US
Performance is consistently excellent
User feedback has been crucial in system development
High benefits now being realized
Convective initiation forecasts still needed
Promising new techniques for automated boundary detection
Displayed: 8 ARTCC, 6 TRACONS, Command center, major airline carriers.

16. End of presentation