700
UXUS97 KPUB 081030
SRGPUB
SOARING FORECAST
NATIONAL WEATHER SERVICE PUEBLO CO
330 AM MST SUN NOV 8 2009
EXPERIMENTAL PRODUCT
THIS FORECAST IS FOR SUNDAY NOVEMBER 8, 2009:
IF THE TRIGGER TEMPERATURE OF 60.5 F/15.8 C IS REACHED...THEN
THERMAL SOARING INDEX....................... FAIR
MAXIMUM RATE OF LIFT........................ 210 FT/MIN (1.1 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 11161 FT MSL (3622 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 60.0 F/16.0 C
TIME OF TRIGGER TEMPERATURE.................... 1345 MST
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... OVERCAST THIN HIGH
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 8227 FT MSL (688 FT AGL)
THERMAL SOARING OUTLOOK FOR MONDAY 11/09....... FAIR
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1700 MST)......... DECREASING
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE
WEAK PVA/NVA (THROUGH 1700 MST)................ WEAK PVA
POTENTIAL HEIGHT OF WAVE....................... 14434 FT MSL (6895 FT AGL)
WAVE SOARING OUTLOOK FOR MONDAY 11/09.......... FAIR
REMARKS...
SUNRISE/SUNSET.................... 06:34:44 / 16:51:12 MST
TOTAL POSSIBLE SUNSHINE........... 10 HR 16 MIN 28 SEC (616 MIN 28 SEC)
ALTITUDE OF SUN AT 11:43:11 MST... 34.29 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 11/08/2009 AT 0500 MST
FREEZING LEVEL.................. 13302 FT MSL (5763 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 21342 FT MSL (13803 FT AGL)
LIFTED CONDENSATION LEVEL....... 18711 FT MSL (11172 FT AGL)
LIFTED INDEX.................... +4.3
K INDEX......................... -8.5
HEIGHT TEMPERATURE WIND WIND SPD LAPSE RATE CONVECTIONT THERMAL LIFT RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT DEG C DEG F INDEX FPM M/S
--------------------------------------------------------------------------------
50000 -64.5 -84.1 235 45 23 0.4 0.2 80.1 176.2 38.1 M M
45000 -63.7 -82.7 232 46 24 2.2 1.2 59.2 138.5 27.5 M M
40000 -60.6 -77.1 258 46 24 2.1 1.1 41.1 106.1 17.3 M M
38000 -57.6 -71.7 254 45 23 6.5 3.6 36.9 98.5 14.9 M M
36000 -53.7 -64.7 244 44 23 6.5 3.6 34.1 93.5 13.3 M M
34000 -48.9 -56.0 236 44 22 8.1 4.4 31.8 89.3 12.0 M M
32000 -44.1 -47.4 233 43 22 8.1 4.4 30.5 86.8 11.2 M M
30000 -39.4 -38.9 231 42 22 7.4 4.1 29.0 84.3 10.4 M M
29000 -37.2 -35.0 230 41 21 7.4 4.1 28.1 82.6 9.8 M M
28000 -35.0 -31.0 229 40 21 7.5 4.1 27.3 81.1 9.2 M M
27000 -32.8 -27.0 227 39 20 6.9 3.8 26.4 79.6 8.6 M M
26000 -30.7 -23.3 225 38 20 6.9 3.8 25.3 77.5 7.8 M M
25000 -28.6 -19.5 223 37 19 6.9 3.8 24.3 75.7 7.1 M M
24000 -26.5 -15.7 221 36 19 8.9 4.9 23.4 74.2 6.4 M M
23000 -23.7 -10.7 220 35 18 9.2 5.1 23.2 73.7 6.3 M M
22000 -20.9 -5.6 219 34 17 9.3 5.1 23.0 73.4 6.3 M M
21000 -18.2 -0.8 218 32 16 7.9 4.3 22.8 73.0 6.1 M M
20000 -15.8 3.6 221 29 15 8.1 4.4 22.1 71.8 5.7 M M
19500 -14.6 5.7 222 28 14 8.1 4.4 21.8 71.3 5.4 M M
19000 -13.4 7.9 224 26 14 8.1 4.4 21.6 70.8 5.2 M M
18500 -12.2 10.0 225 25 13 7.5 4.1 21.3 70.3 5.0 M M
18000 -10.6 12.9 223 22 11 7.3 4.0 20.7 69.2 4.5 M M
17500 -9.5 14.9 223 21 11 6.9 3.8 20.2 68.4 4.1 M M
17000 -8.5 16.7 230 19 10 6.8 3.8 19.7 67.5 3.7 M M
16500 -7.5 18.5 238 19 10 7.1 3.9 19.3 66.7 3.3 M M
16000 -6.4 20.5 240 17 9 7.6 4.2 18.9 66.0 2.9 M M
15500 -5.2 22.6 240 16 8 7.5 4.1 18.5 65.4 2.6 M M
15000 -4.0 24.8 243 16 8 8.4 4.6 18.2 64.8 2.3 M M
14500 -2.8 27.0 247 17 9 8.4 4.6 18.0 64.4 2.1 M M
14000 -1.6 29.1 251 18 9 8.2 4.5 17.8 64.0 1.9 M M
13500 -0.4 31.3 258 20 10 8.1 4.5 17.5 63.5 1.7 M M
13000 0.8 33.4 263 22 11 7.5 4.1 17.2 63.0 1.4 M M
12500 1.9 35.4 265 24 12 7.2 3.9 16.8 62.3 1.0 M M
12000 2.9 37.2 267 26 14 7.3 4.0 16.4 61.6 0.6 M M
11750 3.5 38.3 266 25 13 7.5 4.1 16.2 61.2 0.4 M M
11500 4.0 39.2 265 24 13 7.5 4.1 16.1 60.9 0.2 M M
11250 4.6 40.3 264 23 12 7.5 4.1 15.9 60.6 0.1 M M
11000 5.1 41.2 263 23 12 7.6 4.2 15.7 60.3 -0.1 293 1.5
10750 5.7 42.3 265 23 12 7.8 4.3 15.5 60.0 -0.3 268 1.4
10500 6.3 43.3 266 24 12 7.7 4.2 15.4 59.7 -0.5 244 1.2
10250 6.9 44.4 267 24 13 8.0 4.4 15.2 59.4 -0.6 219 1.1
10000 7.4 45.3 269 25 13 6.9 3.8 15.1 59.2 -0.8 194 1.0
9750 7.9 46.2 270 26 13 5.8 3.2 14.8 58.6 -1.1 174 0.9
9500 8.3 46.9 272 27 14 6.1 3.4 14.5 58.1 -1.4 153 0.8
9250 8.7 47.7 273 28 14 6.0 3.3 14.2 57.6 -1.7 133 0.7
9000 9.2 48.6 275 28 15 6.5 3.6 14.0 57.1 -1.9 112 0.6
8750 9.7 49.5 275 28 14 6.4 3.5 13.7 56.7 -2.2 90 0.5
8500 10.2 50.4 276 27 14 8.0 4.4 13.5 56.3 -2.5 68 0.3
8250 10.6 51.1 276 27 14 1.6 0.9 13.3 55.9 -2.7 46 0.2
8000 9.9 49.8 277 25 13 -22.6 -12.4 11.8 53.3 -4.2 61 0.3
7750 7.3 45.1 277 19 10 -43.1 -23.6 8.5 47.3 -7.6 133 0.7
7500 M M M M M M M M M M M M
7250 M M M M M M M M M M M M
7000 M M M M M M M M M M M M
6750 M M M M M M M M M M M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
11/08/2009 AT 0800 MST | 11/08/2009 AT 1100 MST
|
K INDEX... -3.7 | K INDEX... -2.2
|
HEIGHT TEMPERATURE WND WNDSPD LAPSE RATE | TEMPERATURE WND WNDSPD LAPSE RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT | DEG C DEG F DIR KT M/S C/KM F/KFT
--------------------------------------------------------------------------------
50000 -64.1 -83.4 232 46 24 0.2 0.1 | -63.7 -82.7 231 52 27 -0.6 -0.3
45000 -63.7 -82.7 233 48 25 2.2 1.2 | -64.3 -83.7 230 55 28 2.3 1.3
40000 -60.6 -77.1 254 50 26 2.1 1.1 | -60.9 -77.6 251 56 29 2.3 1.3
38000 -57.6 -71.7 251 49 25 6.4 3.5 | -57.8 -72.0 248 55 28 6.5 3.6
36000 -53.8 -64.8 243 47 24 6.4 3.5 | -53.9 -65.0 238 54 28 6.5 3.6
34000 -49.1 -56.4 236 46 24 8.0 4.4 | -49.2 -56.6 231 53 27 7.6 4.2
32000 -44.3 -47.7 235 45 23 8.0 4.4 | -44.7 -48.5 231 52 27 7.6 4.2
30000 -39.7 -39.5 233 43 22 7.3 4.0 | -40.2 -40.4 231 50 26 7.5 4.1
29000 -37.5 -35.5 231 41 21 7.3 4.0 | -37.9 -36.2 232 49 25 7.5 4.1
28000 -35.3 -31.5 228 39 20 7.3 4.0 | -35.7 -32.3 233 47 24 7.5 4.1
27000 -33.2 -27.8 227 38 19 7.1 3.9 | -33.5 -28.3 233 46 23 6.9 3.8
26000 -31.0 -23.8 227 36 18 7.1 3.9 | -31.4 -24.5 234 43 22 7.0 3.8
25000 -28.9 -20.0 227 34 17 7.1 3.9 | -29.3 -20.7 235 40 21 7.0 3.8
24000 -26.8 -16.2 228 32 16 7.9 4.3 | -27.2 -17.0 236 37 19 7.5 4.1
23000 -24.4 -11.9 230 30 16 8.0 4.4 | -25.0 -13.0 237 35 18 7.6 4.2
22000 -22.0 -7.6 231 29 15 8.0 4.4 | -22.7 -8.9 238 33 17 7.6 4.2
21000 -19.5 -3.1 231 27 14 8.9 4.9 | -20.4 -4.7 238 31 16 8.7 4.8
20000 -16.8 1.8 226 24 12 8.8 4.8 | -17.8 -0.0 233 26 14 8.6 4.7
19500 -15.5 4.1 223 22 11 8.8 4.9 | -16.5 2.3 230 24 12 8.6 4.7
19000 -14.2 6.4 220 21 11 9.0 4.9 | -15.2 4.6 227 22 11 8.6 4.7
18500 -12.9 8.8 218 19 10 7.3 4.0 | -14.0 6.8 224 20 10 7.5 4.1
18000 -11.9 10.6 223 17 9 7.1 3.9 | -12.3 9.9 222 17 9 7.3 4.0
17500 -10.3 13.5 230 14 7 7.3 4.0 | -11.2 11.8 223 16 8 8.2 4.5
17000 -9.2 15.4 231 12 6 7.4 4.1 | -9.9 14.2 232 16 8 8.2 4.5
16500 -8.1 17.4 232 10 5 7.9 4.4 | -8.7 16.3 240 16 8 7.3 4.0
16000 -6.8 19.8 239 11 5 8.8 4.8 | -7.7 18.1 250 17 9 6.2 3.4
15500 -5.5 22.1 247 11 6 8.8 4.8 | -6.8 19.8 259 18 9 6.1 3.4
15000 -4.2 24.4 258 13 6 8.7 4.8 | -5.9 21.4 262 17 9 6.2 3.4
14500 -2.9 26.8 267 15 8 8.9 4.9 | -5.0 23.0 263 16 8 5.9 3.2
14000 -1.7 28.9 274 18 9 6.6 3.6 | -3.9 25.0 262 14 7 8.7 4.8
13500 -0.7 30.7 280 20 10 6.5 3.6 | -2.6 27.3 260 12 6 8.7 4.8
13000 0.3 32.5 283 22 11 7.5 4.1 | -1.4 29.5 258 10 5 8.2 4.5
12500 1.4 34.5 283 19 10 7.7 4.2 | -0.2 31.6 266 9 5 8.1 4.5
12000 2.6 36.7 284 17 9 7.4 4.0 | 1.0 33.8 276 9 4 6.9 3.8
11750 3.1 37.6 285 15 8 7.1 3.9 | 1.4 34.5 285 10 5 6.4 3.5
11500 3.6 38.5 286 14 7 7.2 3.9 | 1.9 35.4 292 11 6 6.6 3.6
11250 4.2 39.6 287 13 6 7.2 4.0 | 2.4 36.3 298 12 6 6.5 3.6
11000 4.7 40.5 288 12 6 6.3 3.4 | 2.9 37.2 302 13 7 6.6 3.6
10750 5.1 41.2 289 14 7 5.5 3.0 | 3.3 37.9 305 13 7 6.6 3.6
10500 5.5 41.9 290 16 8 5.7 3.1 | 3.8 38.8 308 13 7 6.6 3.6
10250 5.9 42.6 291 18 9 5.7 3.1 | 4.3 39.7 312 13 7 6.6 3.6
10000 6.3 43.3 291 20 10 5.3 2.9 | 4.8 40.6 315 13 7 6.8 3.7
9750 6.7 44.1 291 22 11 4.9 2.7 | 5.3 41.5 318 12 6 7.0 3.8
9500 7.0 44.6 290 23 12 5.0 2.8 | 5.8 42.4 323 12 6 6.8 3.7
9250 7.4 45.3 290 25 13 5.1 2.8 | 6.3 43.3 327 11 6 7.5 4.1
9000 7.7 45.9 290 26 14 5.6 3.1 | 6.9 44.4 330 10 5 9.0 4.9
8750 8.2 46.8 289 26 13 5.4 3.0 | 7.5 45.5 331 10 5 9.5 5.2
8500 8.6 47.5 289 25 13 6.9 3.8 | 8.2 46.8 332 9 5 8.9 4.9
8250 9.0 48.2 288 25 13 1.0 0.6 | 8.9 48.0 334 8 4 11.1 6.1
8000 8.5 47.3 287 21 11 -10.4 -5.7 | 9.9 49.8 333 8 4 14.2 7.8
7750 7.6 45.7 287 17 9 -11.5 -6.3 | 10.9 51.6 331 7 4 12.9 7.1
7500 M M M M M M M | M M M M M M M
7250 M M M M M M M | M M M M M M M
7000 M M M M M M M | M M M M M M M
6750 M M M M M M M | M M M M M M M
11/08/2009 AT 1400 MST | 11/08/2009 AT 1700 MST
|
K INDEX... +8.9 | K INDEX... +5.9
|
HEIGHT TEMPERATURE WND WNDSPD LAPSE RATE | TEMPERATURE WND WNDSPD LAPSE RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT | DEG C DEG F DIR KT M/S C/KM F/KFT
--------------------------------------------------------------------------------
50000 -63.3 -81.9 231 52 27 0.1 0.0 | -63.1 -81.6 236 51 26 0.3 0.2
45000 -63.1 -81.6 228 57 30 1.3 0.7 | -62.6 -80.7 232 56 29 1.6 0.9
40000 -61.1 -78.0 244 58 30 1.3 0.7 | -60.2 -76.4 244 60 31 1.6 0.9
38000 -58.2 -72.8 243 59 30 6.9 3.8 | -57.8 -72.0 245 61 31 5.5 3.0
36000 -54.0 -65.2 238 59 30 6.9 3.8 | -54.5 -66.1 244 61 32 5.5 3.0
34000 -49.9 -57.8 235 59 30 7.1 3.9 | -51.0 -59.8 244 60 31 6.7 3.7
32000 -45.1 -49.2 239 56 29 7.1 3.9 | -46.9 -52.4 247 55 28 6.8 3.7
30000 -40.9 -41.6 243 53 27 6.8 3.7 | -42.2 -44.0 250 47 24 7.5 4.1
29000 -38.9 -38.0 245 49 25 6.8 3.7 | -39.9 -39.8 249 42 22 7.5 4.1
28000 -36.9 -34.4 248 46 23 6.8 3.7 | -37.7 -35.9 247 37 19 7.5 4.1
27000 -34.7 -30.5 250 43 22 8.4 4.6 | -35.3 -31.5 247 33 17 9.0 4.9
26000 -32.2 -26.0 250 41 21 8.2 4.5 | -32.7 -26.9 250 32 17 8.8 4.8
25000 -29.8 -21.6 249 39 20 8.2 4.5 | -30.0 -22.0 253 31 16 8.8 4.8
24000 -27.3 -17.1 248 37 19 7.9 4.4 | -27.4 -17.3 256 30 15 8.1 4.4
23000 -24.9 -12.8 247 35 18 7.9 4.3 | -25.0 -13.0 257 27 14 7.9 4.3
22000 -22.6 -8.7 246 33 17 7.9 4.3 | -22.7 -8.9 259 24 13 7.9 4.3
21000 -20.3 -4.5 244 30 15 7.3 4.0 | -20.4 -4.7 260 22 11 7.1 3.9
20000 -18.1 -0.6 240 27 14 7.4 4.1 | -18.2 -0.8 258 22 11 7.2 4.0
19500 -17.0 1.4 238 25 13 7.5 4.1 | -17.1 1.2 257 22 11 7.2 4.0
19000 -15.9 3.4 236 24 12 7.6 4.2 | -16.0 3.2 256 22 11 7.3 4.0
18500 -14.8 5.4 233 22 11 6.6 3.6 | -15.0 5.0 255 21 11 6.2 3.4
18000 -13.9 7.0 233 21 11 6.4 3.5 | -14.1 6.6 257 21 11 6.0 3.3
17500 -12.4 9.7 232 19 10 6.8 3.7 | -13.2 8.2 259 21 11 5.8 3.2
17000 -11.4 11.5 234 18 9 6.9 3.8 | -12.1 10.2 259 21 11 5.2 2.8
16500 -10.3 13.5 236 17 9 6.6 3.6 | -11.4 11.5 258 21 11 5.3 2.9
16000 -9.4 15.1 233 17 9 6.1 3.4 | -10.7 12.7 252 20 10 5.6 3.1
15500 -8.5 16.7 229 17 9 6.1 3.4 | -9.9 14.2 245 20 10 5.9 3.2
15000 -7.6 18.3 227 16 8 7.2 3.9 | -8.9 16.0 238 19 10 8.7 4.8
14500 -6.5 20.3 226 15 8 7.2 3.9 | -7.7 18.1 232 18 9 8.5 4.7
14000 -5.6 21.9 225 13 7 6.2 3.4 | -6.4 20.5 226 18 9 8.5 4.7
13500 -4.7 23.5 228 11 6 6.2 3.4 | -5.2 22.6 220 17 9 8.6 4.7
13000 -3.7 25.3 229 9 5 7.6 4.2 | -3.9 25.0 215 17 9 7.5 4.1
12500 -2.6 27.3 220 8 4 7.9 4.3 | -2.9 26.8 208 16 8 7.4 4.0
12000 -1.4 29.5 207 6 3 8.6 4.7 | -1.8 28.8 202 15 8 7.2 4.0
11750 -0.8 30.6 199 5 3 8.9 4.9 | -1.2 29.8 199 14 7 7.2 3.9
11500 -0.1 31.8 186 4 2 8.7 4.8 | -0.7 30.7 196 12 6 7.2 4.0
11250 0.5 32.9 170 4 2 8.9 4.9 | -0.2 31.6 192 11 6 7.2 3.9
11000 1.2 34.2 154 4 2 9.4 5.2 | 0.4 32.7 186 10 5 7.0 3.8
10750 1.9 35.4 143 4 2 9.7 5.3 | 0.9 33.6 176 8 4 6.9 3.8
10500 2.6 36.7 132 4 2 9.7 5.3 | 1.4 34.5 164 7 4 6.9 3.8
10250 3.4 38.1 122 4 2 9.7 5.3 | 1.9 35.4 149 7 3 7.3 4.0
10000 4.1 39.4 116 5 2 9.9 5.5 | 2.5 36.5 136 7 3 8.3 4.5
9750 4.8 40.6 113 5 2 10.0 5.5 | 3.1 37.6 126 7 4 8.6 4.7
9500 5.6 42.1 110 5 3 10.0 5.5 | 3.7 38.7 118 7 4 8.5 4.6
9250 6.3 43.3 107 5 3 10.0 5.5 | 4.4 39.9 111 8 4 8.7 4.8
9000 7.1 44.8 105 5 3 9.8 5.4 | 5.0 41.0 107 9 4 9.1 5.0
8750 7.8 46.0 103 6 3 10.0 5.5 | 5.7 42.3 105 9 5 8.9 4.9
8500 8.5 47.3 101 6 3 9.2 5.0 | 6.4 43.5 103 10 5 9.8 5.4
8250 9.3 48.7 099 6 3 12.2 6.7 | 7.0 44.6 101 10 5 5.9 3.3
8000 10.4 50.7 098 6 3 16.3 8.9 | 7.2 45.0 103 8 4 1.4 0.8
7750 11.5 52.7 097 6 3 13.9 7.6 | 7.4 45.3 105 7 4 4.9 2.7
7500 M M M M M M M | M M M M M M M
7250 M M M M M M M | M M M M M M M
7000 M M M M M M M | M M M M M M M
6750 M M M M M M M | M M M M M M M
________________________________________________________________________________
THIS PRODUCT IS ISSUED ONE PER DAY BY APPROXIMATELY 0630 MST/0730 MDT
(1330 UTC). IT IS NOT CONTINUOUSLY MONITORED NOR UPDATED AFTER ITS INITIAL
ISSUANCE.
THE INFORMATION CONTAINED HEREIN IS BASED ON NUMERICAL WEATHER PREDICTION
MODEL DATA TAKEN NEAR THE AIR FORCE ACADEMY IN COLORADO SPRINGS, COLORADO
AT
NORTH LATITUDE: 38 DEG 58 MIN 48.000 SEC
WEST LONGITUDE: 104 DEG 49 MIN 12.000 SEC
ELEVATION: 6572 FEET (2003 METERS)
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE FRONT RANGE OF THE
COLORADO ROCKY MOUNTAINS. NOTE THAT SOME ELEVATIONS IN NUMERICAL WEATHER
PREDICTION MODELS DIFFER FROM ACTUAL STATION ELEVATIONS, WHICH CAN LEAD TO
DATA WHICH APPEAR TO BE BELOW GROUND. ERRONEOUS DATA SUCH AS THESE SHOULD
NOT BE USED.
THE CONTENT AND FORMAT OF THIS REPORT AS WELL AS THE ISSUANCE TIMES ARE SUBJECT
TO CHANGE WITHOUT PRIOR NOTICE. COMMENTS AND SUGGESTIONS ARE WELCOME AND SHOULD
BE DIRECTED TO ONE OF THE ADDRESSES OR PHONE NUMBERS SHOWN AT THE BOTTOM OF THIS
PAGE. TO EXPEDITE A RESPONSE TO COMMENTS, BE SURE TO MENTION YOUR INTEREST IN
THE SOARING FORECAST.
AT THIS TIME, THE OUTPUT FROM THIS CONSIDERED EXPERIMENTAL.
DEFINITIONS:
CONVECTIVE CONDENSATION LEVEL - THE HEIGHT TO WHICH AN AIR PARCEL POSSESSING THE
AVERAGE SATURATION MIXING RATIO IN THE LOWEST 4000 FEET OF THE AIRMASS,
IF HEATED SUFFICIENTLY FROM BELOW, WILL RISE DRY ADIABATICALLY UNTIL IT
JUST BECOMES SATURATED. IT ESTIMATES THE BASE OF CUMULUS CLOUDS THAT ARE
PRODUCED BY SURFACE HEATING ONLY.
CONVECTION TEMPERATURE (CONVECTIONT) - THE SURFACE TEMPERATURE REQUIRED TO MAKE
THE AIRMASS DRY ADIABATIC UP TO THE GIVEN LEVEL. IT CAN BE CONSIDERED A
"TRIGGER TEMPERATURE" FOR THAT LEVEL.
FREEZING LEVEL - THE HEIGHT WHERE THE TEMPERATURE IS ZERO DEGREES CELSIUS.
HEIGHT OF STABLE LAYER - THE HEIGHT (BETWEEN 12,000 AND 18,000 FEET ABOVE
MEAN SEA LEVEL) WHERE THE SMALLEST LAPSE RATE EXISTS. THE LOCATION AND
EXISTENCE OF THIS FEATURE IS IMPORTANT IN THE GENERATION OF MOUNTAIN
WAVES.
K INDEX - A MEASURE OF STABILITY WHICH COMBINES THE TEMPERATURE DIFFERENCE
BETWEEN APPROXIMATELY 5,000 AND 18,000 FEET ABOVE THE SURFACE, THE AMOUNT
OF MOISTURE AT APPROXIMATELY 5,000 FEET ABOVE THE SURFACE, AND A MEASURE
OF THE DRYNESS AT APPROXIMATELY 10,000 FEET ABOVE THE SURFACE. LARGER
POSITIVE NUMBERS INDICATE MORE INSTABILITY AND A GREATER LIKELIHOOD OF
THUNDERSTORM DEVELOPMENT. ONE INTERPRETATION OF K INDEX VALUES REGARDING
SOARING IN THE WESTERN UNITED STATES IS GIVEN IN WMO TECHNICAL NOTE 158
AND IS REPRODUCED IN THE FOLLOWING TABLE:
BELOW -10 NO OR WEAK THERMALS
-10 TO 5 DRY THERMALS OR 1/8 CUMULUS WITH MODERATE THERMALS
5 TO 15 GOOD SOARING CONDITIONS
15 TO 20 GOOD SOARING CONDITIONS WITH OCCASIONAL SHOWERS
20 TO 30 EXCELLENT SOARING CONDITIONS, BUT INCREASING
PROBABILITY OF SHOWERS AND THUNDERSTORMS
ABOVE 30 MORE THAN 60 PERCENT PROBABILITY OF THUNDERSTORMS
LAPSE RATE - THE CHANGE WITH HEIGHT OF THE TEMPERATURE. NEGATIVE VALUES INDICATE
INVERSIONS.
LIFTED CONDENSATION LEVEL - THE HEIGHT TO WHICH AN AIR PARCEL POSSESSING THE
AVERAGE DEW POINT IN THE LOWEST 4000 FEET OF THE AIRMASS AND THE FORECAST
MAXIMUM TEMPERATURE MUST BE LIFTED DRY ADIABATICALLY TO ATTAIN SATURATION.
LIFTED INDEX - THE DIFFERENCE BETWEEN THE ENVIRONMENTAL TEMPERATURE AT A LEVEL
APPROXIMATELY 18,000 FEET ABOVE THE SURFACE AND THE TEMPERATURE OF AN AIR
PARCEL LIFTED DRY ADIABATICALLY FROM THE SURFACE TO ITS LIFTED CONDENSATION
LEVEL AND THEN PSEUDOADIABATICALLY THEREAFTER TO THIS SAME LEVEL. THE
PARCEL'S INITIAL TEMPERATURE IS THE FORECAST MAXIMUM TEMPERATURE AND ITS
DEW POINT IS THE AVERAGE DEW POINT IN THE LOWEST 4000 FEET OF THE AIRMASS.
NEGATIVE VALUES ARE INDICATIVE OF INSTABILITY WITH POSITIVE VALUES SHOWING
STABLE CONDITIONS.
LIFT RATE - AN EXPERIMENTAL ESTIMATE OF THE STRENGTH OF THERMALS. IT IS
COMPUTED THE SAME WAY AS THE MAXIMUM RATE OF LIFT BUT USES THE ACTUAL
LEVEL RATHER THAN THE MAXIMUM HEIGHT OF THERMALS IN THE CALCULATION.
ALSO, NONE OF THE EMPIRICAL ADJUSTMENTS BASED ON CLOUDINESS AND K-INDEX
ARE APPLIED TO THESE CALCULATIONS.
MAXIMUM HEIGHT OF THERMALS - THE HEIGHT WHERE THE DRY ADIABAT THROUGH THE
FORECAST MAXIMUM TEMPERATURE INTERSECTS THE ENVIRONMENTAL TEMPERATURE.
MAXIMUM RATE OF LIFT - AN ESTIMATE OF THE MAXIMUM STRENGTH OF THERMALS. IT
IS COMPUTED FROM AN EMPIRICAL FORMULA WHICH COMBINES THE EXPECTED MAXIMUM
HEIGHT OF THERMALS WITH THE DIFFERENCE IN THE ENVIRONMENTAL TEMPERATURES
BETWEEN THE MAXIMUM HEIGHT OF THERMALS AND THE TEMPERATURE 4,000 FEET
ABOVE THE GROUND. AFTER THIS COMPUTATION, FURTHER EMPIRICAL ADJUSTMENTS
ARE MADE BASED ON THE VALUE OF THE K-INDEX AND THE AMOUNT AND OPACITY OF
MIDDLE AND HIGH LEVEL CLOUDINESS EXPECTED BETWEEN THE TIME OF TRIGGER
TEMPERATURE AND THE TIME OF OVERDEVELOPMENT.
MIDDLE/HIGH CLOUDS - THE AMOUNT AND OPACITY OF MIDDLE (ALTOSTRATUS, ALTOCUMULUS)
OR HIGH (CIRRUS, CIRROSTATUS, CIRROCUMULUS) CLOUDS. BROKEN MEANS THAT
BETWEEN 60% AND 90% OF THE SKY IS COVERED BY THE CLOUD, WITH OVERCAST
CONDITIONS OCCURRING WHEN MORE THAN 90% OF THE SKY IS COVERED BY THE CLOUD.
THIN IMPLIES THAT THE CLOUDS ARE PREDOMINANTLY TRANSPARENT, MEANING THAT
SOME SUNLIGHT IS REACHING THE GROUND, IN CONTRAST TO OPAQUE WHICH SUGGESTS
THAT LITTLE SUNLIGHT IS REACHING THE GROUND.
POTENTIAL HEIGHT OF WAVE - THE MINIMUM OF THE FOLLOWING TWO HEIGHTS:
1. LEVEL ABOVE THE HEIGHT OF STABLE LAYER (OR 14,000 FEET IF NONE EXISTS)
WHERE THE WIND DIRECTION CHANGES BY 30 DEGREES OR MORE
2. LEVEL ABOVE THE HEIGHT OF STABLE LAYER (OR 14,000 FEET IF NONE EXISTS)
WHERE THE WIND SPEED NO LONGER INCREASES WITH HEIGHT
PVA/NVA - POSITIVE VORTICITY ADVECTION (PVA)/NEGATIVE VORTICITY ADVECTION (NVA)
ON THE 500 MILLIBAR ISOBARIC SURFACE (APPROXIMATELY 18,000 FEET ABOVE MEAN
SEA LEVEL). WEAK PVA HAS BEEN SHOWN TO ASSIST IN MOUNTAIN WAVE SOARING.
SOARING WINDOW - THE TIME BETWEEN THE TIME THE TRIGGER TEMPERATURE IS REACHED
AND THE TIME OF OVERDEVELOPMENT.
THERMAL INDEX - THE DIFFERENCE BETWEEN THE ENVIRONMENTAL TEMPERATURE AND THE
TEMPERATURE AT A PARTICULAR LEVEL DETERMINED BY FOLLOWING THE DRY ADIABAT
THROUGH THE FORECAST MAXIMUM TEMPERATURE UP TO THAT LEVEL. NEGATIVE VALUES
ARE INDICATIVE OF THERMAL LIFT.
THERMAL SOARING INDEX - AN ADJECTIVE RATING (FOR SAILPLANES) BASED ON THE
COMPUTED MAXIMUM RATE OF LIFT, AND THE WIND SPEED AND MIDDLE AND HIGH
CLOUD COVER EXPECTED DURING THE SOARING WINDOW (THE TIME OF THE TRIGGER
TEMPERATURE AND THE TIME OF OVERDEVELOPMENT) ACCORDING TO THE FOLLOWING:
MAXIMUM RATE OF LIFT ADJECTIVE RATING
>= 800 FPM EXCELLENT
>= 400 AND < 800 FPM GOOD
>= 200 AND < 400 FPM FAIR
< 200 FPM POOR
TIME OF OVERDEVELOPMENT - THE TIME ONE OR MORE OF THE FOLLOWING PHENOMENA,
WHICH ESSENTIALLY SHUT OFF THERMAL LIFT, IS EXPECTED TO OCCUR:
1. FORMATION OF BROKEN TO OVERCAST CONVECTIVE CLOUD COVER
2. FORMATION OF SCATTERED TO NUMEROUS DOWNBURSTS
3. INITIATION OF WIDESPREAD PRECIPITATION
TIME OF TRIGGER TEMPERATURE - THE TIME THE SURFACE TEMPERATURE IS EXPECTED TO
REACH THE TRIGGER TEMPERATURE.
TRIGGER TEMPERATURE - THE SURFACE TEMPERATURE REQUIRED TO MAKE THE FIRST 4000
FEET OF THE ATMOSPHERE DRY ADIABATIC.
WAVE SOARING INDEX - AN EMPIRICAL, ADJECTIVE RATING (FOR SAILPLANES) WHICH
ATTEMPTS TO COMBINE A VARIETY OF PHENOMENA IMPORTANT IN MOUNTAIN WAVE
SOARING INTO A SINGLE INDEX NUMBER. OBJECTIVE POINTS ARE ASSIGNED TO
THESE PHENOMENA: WIND SPEED AND DIRECTION AT 14,000 FT MSL, THE STATIC
STABILITY IN THE 12,000-18,000 FT MSL LAYER, THE WIND SPEED GRADIENT ABOVE
THE STABLE LAYER, JET STREAM LOCATION AND FRONTAL AND UPPER TROUGH
MOVEMENTS.
071806
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