Effects of Synoptic Surveillance on model forecasts for
29 August 2006 0000 UTC
Ernesto.


Quicktime movie of AVN DLM wind model forecast
Quicktime movie of DLM wind data increment


TRACK AND INTENSITY PERFORMANCE

TRACK (km)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN 39 33 10 20 33 43 38 99172112
AVNO 15 49 24 35104119140246381481
%IMP62%-48%-140%-75%-215%-177%-268%-148%-122%-329%
GFNO132 69 10 37 97214279490633640
GFDL 83 59 56 30123199250456663774
%IMP37%14%-460%19%-27% 8%10% 7%-5%-21%
INTENSITY (kt)
MODEL12 h24 h36 h48 h60 h72 h84 h96 h108 h120 h
AVNN -7 -7 -4 -5-21-26 3 -7-16-17
AVNO -9-10 -2 -2-20-24 4 -6-11-19
%IMP-29%-43%50%60% 5% 8%-33%14%31%-12%
GFNO 8 10 18 28 12 2 -8 14 13 13
GFDL 2 14 29 19 10 -9-10 6 12 -6
%IMP75%-40%-61%32%17%-350%-25%57% 8%54%

Landfall forecasts

30/0300 UTC 24.9N 80.6W Plantation Key, FL, 27 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 24.8880.68 27.5 8.4Islamorada, FL
AVNO 24.8280.90 28.5 31.5Layton, FL
%IMP-200%-275%
GFNO 25.2180.37 29.5 41.5Key Largo, FL
GFDL 24.8680.68 30.0 9.2Islamorada, FL
%IMP-20% 78%
30/0500 UTC 25.2N 80.7W Southwestern Miami-Dade County, FL, 29 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 25.1680.82 29.5 12.9Flamingo, FL
AVNO 25.1481.01 31.0109.0Flamingo, FL
%IMP-300%-745%
GFNO 25.2180.37 29.5117.0Key Largo, FL
GFDL 25.1580.80 32.5106.0Flamingo, FL
%IMP-600%9%
01/0340 UTC 33.9N 78.1W Oak Island, NC, 75.75 h into the forecast
MODELLATLONTIMEERRORLOCATION
AVNN 33.8278.64 74.0 50.6North Myrtle Beach, SC
AVNO 33.0279.58 67.0168.5Bull Bay, SC
%IMP-400%-233%
GFNO 32.5280.13 64.0243.1Seabrook Island, SC
GFDL 32.4080.65 64.0289.9Hilton Head Island, SC
%IMP0% -19%

Figure 1. NCEP 850 - 200 hPa mean wind analysis for 29 August 2006 0000 UTC (Tropical Storm Ernesto).

Figure 2. Track forecasts for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the AVN and GFDL models initialized on 29 August 2006 0000 UTC.

Figure 3. NCEP Global Ensemble Prediction System track forecasts for all cyclones in the Atlantic basin initialized from 27 August 2006 0600 UTC to 28 August 2006 0000 UTC, showing the tracks of Tropical Storm Ernesto.

Figure 4. Ensemble perturbation variance at the nominal sampling time 29 August 2006 0000 UTC from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations.

Figure 5. Variance explained within the verification region (large red circle) for observations taken at the sampling time 29 August 2006 0000 UTC from the Ensemble Transform Kalman Filter run from the previous day NCEP ensemble forecast. The green circles represent the dropwindsonde locations. [not available]

Figure 6. Adjoint-Derived Steering Sensitivity Vector for observations taken at the sampling time 29 August 2006 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 7. NOGAPS Singular Vector for observations taken at the sampling time 29 August 2006 0000 UTC. The green circles represent the dropwindsonde locations.

Figure 8. Initial condition differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 29 August 2006 0000 UTC. The circles represent the dropwindsonde locations.

Figure 9. 12-h forecast differences in the 850 - 200 hPa mean wind between the no and all dropwindsonde cases for 29 August 2006 0000 UTC.