Upper Tropo Influences

Influences of upper tropospheric data

During the 1997 and 1998 hurricane seasons, a total of 27 synoptic surveillance missions have been flown. The following is a summary of the completed assessments.

**Table 1**
Track forecast errors for the no dropwindsonde GFDL control (GFNO), the all dropwindsonde run (GFAL), the lower-level dropwindsonde run (GFP3), and the run with only targeted observations (GFTG), and the percent improvement of the latter three over the control.
Forecast time (h)	Cases	GFNO Error (km)	GFAL Error (km) (% Improvement)		GFP3 Error (km) (% Improvement)		GFTG Error (km) (% Improvement)
12	18	72.9	60.3	( 17%)	60.6	( 17%)	59.4	( 19%)
24	18	107.5	103.0	( 4%)	101.5	( 6%)	89.2	( 17%)
36	18	159.9	143.8	( 10%)	141.1	( 12%)	132.2	( 17%)
48	16	191.0	193.3	( -1%)	197.4	( -3%)	163.1	( 15%)
72	15	386.5	387.0	( 0%)	406.4	( -5%)	325.5	( 16%)
84	15	442.8	478.0	( -8%)	489.8	(-11%)	421.2	( 5%)
96	14	568.7	624.8	(-10%)	645.8	(-14%)	560.3	( 1%)
108	14	705.9	738.0	( -5%)	769.0	( -9%)	684.8	( 3%)
120	10	966.4	914.2	( 5%)	948.2	( 2%)	892.4	( 8%)

Table 2
Track forecast errors for the no dropwindsonde VBAR control (VBNO), the all dropwindsonde run (VBAL), the lower-level dropwindsonde run (VBP3), and the run with only targeted observations (VBTG), and the percent improvement of the latter three over the control.
Forecast
time (h) Cases VBNO
Error (km) VBAL Error (km)
(% Improvement) VBP3 Error (km)
(% Improvement) VBTG Error (km)
(% Improvement)
12 16 68.2 62.1 ( 9%) 61.0 ( 11%) 64.3 ( 6%)
24 16 116.0 107.7 ( 7%) 107.9 ( 7%) 110.0 ( 5%)
36 16 154.2 139.5 ( 10%) 141.6 ( 8%) 147.5 ( 4%)
48 14 210.9 195.0 ( 8%) 194.7 ( 8%) 212.0 ( -1%)
72 14 432.0 445.4 ( -3%) 428.2 ( 1%) 431.6 ( 0%)
84 14 595.1 584.2 ( 2%) 569.2 ( 4%) 578.5 ( 3%)
96 13 794.5 758.8 ( 4%) 742.8 ( 7%) 762.3 ( 4%)
108 13 1006.8 932.3 ( 7%) 921.2 ( 9%) 944.2 ( 6%)
120 11 968.5 878.2 ( 9%) 858.0 ( 13%) 869.3 ( 10%)

**Table 2**
Track forecast errors for the no dropwindsonde VBAR control (VBNO), the all dropwindsonde run (VBAL), the lower-level dropwindsonde run (VBP3), and the run with only targeted observations (VBTG), and the percent improvement of the latter three over the control.
Forecast time (h)	Cases	VBNO Error (km)	VBAL Error (km) (% Improvement)	VBP3 Error (km) (% Improvement)	VBTG Error (km) (% Improvement)
12	16	68.2	62.1	( 9%)	61.0	( 11%)	64.3	( 6%)
24	16	116.0	107.7	( 7%)	107.9	( 7%)	110.0	( 5%)
36	16	154.2	139.5	( 10%)	141.6	( 8%)	147.5	( 4%)
48	14	210.9	195.0	( 8%)	194.7	( 8%)	212.0	( -1%)
72	14	432.0	445.4	( -3%)	428.2	( 1%)	431.6	( 0%)
84	14	595.1	584.2	( 2%)	569.2	( 4%)	578.5	( 3%)
96	13	794.5	758.8	( 4%)	742.8	( 7%)	762.3	( 4%)
108	13	1006.8	932.3	( 7%)	921.2	( 9%)	944.2	( 6%)
120	11	968.5	878.2	( 9%)	858.0	( 13%)	869.3	( 10%)

Table 3
Track forecast errors for the no dropwindsonde GSM control (GSNO), the all dropwindsonde run (GSAL), the lower-level dropwindsonde run (GSP3), and the run with only targeted observations (GSTG), and the percent improvement of the latter three over the control.
Forecast
time (h) Cases GSNO
time (h) GSAL Error (km)
Error (km) GSP3 Error (km)
(% Improvement) GSTG Error (km)
(% Improvement)
12 18 106.7 90.2 ( 15%) 90.6 ( 15%) 92.1 ( 14%)
24 17 163.4 156.7 ( 4%) 155.6 ( 5%) 152.6 ( 7%)
36 17 240.2 223.8 ( 7%) 224.5 ( 7%) 222.3 ( 7%)
48 16 323.3 293.8 ( 9%) 300.0 ( 7%) 295.4 ( 9%)
72 14 484.8 490.9 ( -1%) 512.3 ( -6%) 456.6 ( 6%)
84 14 655.6 664.0 ( -1%) 680.2 ( -4%) 627.6 ( 4%)
96 13 842.5 839.6 ( 0%) 866.1 ( -3%) 817.0 ( 3%)
108 13 1014.6 991.9 ( 2%) 1028.0 ( -1%) 999.4 ( 1%)
120 11 1169.0 1198.8 ( -3%) 1260.7 ( -8%) 1216.3 ( -4%)

**Table 3**
Track forecast errors for the no dropwindsonde GSM control (GSNO), the all dropwindsonde run (GSAL), the lower-level dropwindsonde run (GSP3), and the run with only targeted observations (GSTG), and the percent improvement of the latter three over the control.
Forecast time (h)	Cases	GSNO time (h)	GSAL Error (km) Error (km)	GSP3 Error (km) (% Improvement)	GSTG Error (km) (% Improvement)
12	18	106.7	90.2	( 15%)	90.6	( 15%)	92.1	( 14%)
24	17	163.4	156.7	( 4%)	155.6	( 5%)	152.6	( 7%)
36	17	240.2	223.8	( 7%)	224.5	( 7%)	222.3	( 7%)
48	16	323.3	293.8	( 9%)	300.0	( 7%)	295.4	( 9%)
72	14	484.8	490.9	( -1%)	512.3	( -6%)	456.6	( 6%)
84	14	655.6	664.0	( -1%)	680.2	( -4%)	627.6	( 4%)
96	13	842.5	839.6	( 0%)	866.1	( -3%)	817.0	( 3%)
108	13	1014.6	991.9	( 2%)	1028.0	( -1%)	999.4	( 1%)
120	11	1169.0	1198.8	( -3%)	1260.7	( -8%)	1216.3	( -4%)

Table 4
Intensity forecast errors for the no dropwindsonde GFDL control (GFNO), the all dropwindsonde run (GFAL), the lower-level dropwindsonde run (GFP3), and the run with only targeted observations (GFTG), and the percent improvement of the latter three over the control.
Forecast
time (h) Cases GFNO
Error (kn) GFAL Error (kn)
(% Improvement) GFP3 Error (kn)
(% Improvement) GFTG Error (kn)
(% Improvement)
12 18 15.1 15.6 ( -3%) 15.8 ( -5%) 15.4 ( -2%)
24 18 12.4 12.3 ( 1%) 13.0 ( -5%) 13.1 ( -6%)
36 18 14.4 14.8 ( -3%) 14.6 ( -1%) 14.5 ( -1%)
48 16 9.1 10.4 (-14%) 9.9 ( -9%) 10.5 (-16%)
72 15 8.3 8.5 ( -2%) 8.8 ( -6%) 9.0 ( -8%)
84 15 11.0 10.5 ( 5%) 10.8 ( 2%) 11.0 ( 0%)
96 14 10.4 9.7 ( 7%) 10.6 ( -2%) 11.3 ( -9%)
108 14 12.4 11.8 ( 5%) 12.2 ( 2%) 12.4 ( 0%)
120 10 11.2 11.2 ( 0%) 11.0 ( 2%) 12.4 (-11%)

**Table 4**
Intensity forecast errors for the no dropwindsonde GFDL control (GFNO), the all dropwindsonde run (GFAL), the lower-level dropwindsonde run (GFP3), and the run with only targeted observations (GFTG), and the percent improvement of the latter three over the control.
Forecast time (h)	Cases	GFNO Error (kn)	GFAL Error (kn) (% Improvement)	GFP3 Error (kn) (% Improvement)	GFTG Error (kn) (% Improvement)
12	18	15.1	15.6	( -3%)	15.8	( -5%)	15.4	( -2%)
24	18	12.4	12.3	( 1%)	13.0	( -5%)	13.1	( -6%)
36	18	14.4	14.8	( -3%)	14.6	( -1%)	14.5	( -1%)
48	16	9.1	10.4	(-14%)	9.9	( -9%)	10.5	(-16%)
72	15	8.3	8.5	( -2%)	8.8	( -6%)	9.0	( -8%)
84	15	11.0	10.5	( 5%)	10.8	( 2%)	11.0	( 0%)
96	14	10.4	9.7	( 7%)	10.6	( -2%)	11.3	( -9%)
108	14	12.4	11.8	( 5%)	12.2	( 2%)	12.4	( 0%)
120	10	11.2	11.2	( 0%)	11.0	( 2%)	12.4	(-11%)

Table 5
Track forecast errors for the no dropwindsonde MEAN control (MNNO), the all dropwindsonde run (MNAL), the lower-level dropwindsonde run (MNP3), and the run with only targeted observations (MNTG), and the percent improvement of the latter three over the control.
Forecast
time (h) Cases MNNO
Error (km) MNAL Error (km)
(% Improvement) MNP3 Error (km)
(% Improvement) MNTG Error (km)
(% Improvement)
12 17 69.9 59.8 ( 14%) 61.2 ( 12%) 55.6 ( 20%)
24 17 117.6 106.2 ( 10%) 102.9 ( 13%) 101.1 ( 14%)
36 17 161.8 136.8 ( 15%) 133.3 ( 18%) 140.1 ( 13%)
48 15 198.6 181.5 ( 9%) 174.2 ( 12%) 188.7 ( 5%)
72 14 316.7 308.2 ( 3%) 312.9 ( 1%) 314.6 ( 1%)
84 14 434.0 417.0 ( 4%) 438.2 ( -1%) 447.9 ( -3%)
96 13 670.6 652.7 ( 3%) 674.2 ( -1%) 682.2 ( -2%)
108 13 838.3 787.7 ( 6%) 820.1 ( 2%) 820.6 ( 2%)
120 13 1099.6 1095.4 ( 0%) 1092.2 ( 1%) 1119.4 ( -2%)

Forecast time (h)	Cases	MNNO Error (km)	MNAL Error (km) (% Improvement)		MNP3 Error (km) (% Improvement)		MNTG Error (km) (% Improvement)
12	17	69.9	59.8	( 14%)	61.2	( 12%)	55.6	( 20%)
24	17	117.6	106.2	( 10%)	102.9	( 13%)	101.1	( 14%)
36	17	161.8	136.8	( 15%)	133.3	( 18%)	140.1	( 13%)
48	15	198.6	181.5	( 9%)	174.2	( 12%)	188.7	( 5%)
72	14	316.7	308.2	( 3%)	312.9	( 1%)	314.6	( 1%)
84	14	434.0	417.0	( 4%)	438.2	( -1%)	447.9	( -3%)
96	13	670.6	652.7	( 3%)	674.2	( -1%)	682.2	( -2%)
108	13	838.3	787.7	( 6%)	820.1	( 2%)	820.6	( 2%)
120	13	1099.6	1095.4	( 0%)	1092.2	( 1%)	1119.4	( -2%)