403
UXUS97 KPUB 241337
SRGPUB
SOARING FORECAST
NATIONAL WEATHER SERVICE PUEBLO CO
637 AM MST TUE NOV 24 2009
EXPERIMENTAL PRODUCT
THIS FORECAST IS FOR TUESDAY NOVEMBER 24, 2009:
IF THE TRIGGER TEMPERATURE OF 36.0 F/2.2 C IS REACHED...THEN
THERMAL SOARING INDEX....................... GOOD
MAXIMUM RATE OF LIFT........................ 463 FT/MIN (2.4 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 13706 FT MSL (6172 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 45.0 F/7.7 C
TIME OF TRIGGER TEMPERATURE.................... 1030 MST
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 12405 FT MSL (4870 FT AGL)
THERMAL SOARING OUTLOOK FOR WEDNESDAY 11/25.... GOOD
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1700 MST)......... DECREASING
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... 12208 FT MSL (4674 FT AGL)
WEAK PVA/NVA (THROUGH 1700 MST)................ NEITHER
POTENTIAL HEIGHT OF WAVE....................... 18604 FT MSL (11070 FT AGL)
WAVE SOARING OUTLOOK FOR WEDNESDAY 11/25....... POOR
REMARKS...
SUNRISE/SUNSET.................... 06:52:16 / 16:39:52 MST
TOTAL POSSIBLE SUNSHINE........... 9 HR 47 MIN 37 SEC (587 MIN 37 SEC)
ALTITUDE OF SUN AT 11:46:13 MST... 30.39 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 11/24/2009 AT 0500 MST
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C
CONVECTIVE CONDENSATION LEVEL... 23532 FT MSL (15998 FT AGL)
LIFTED CONDENSATION LEVEL....... 20362 FT MSL (12828 FT AGL)
LIFTED INDEX.................... +7.0
K INDEX......................... -24.3
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 -58.6 -73.5 293 24 13 2.0 1.1 94.1 201.4 50.8 M M
45000 -55.4 -67.7 309 32 17 2.4 1.3 75.6 168.0 42.7 M M
40000 -57.4 -71.3 313 54 28 -1.5 -0.8 49.5 121.0 28.3 M M
38000 -57.7 -71.9 315 60 31 1.5 0.8 40.7 105.3 23.0 M M
36000 -56.8 -70.2 323 60 31 1.6 0.9 33.4 92.1 18.5 M M
34000 -55.9 -68.6 330 61 32 3.2 1.7 27.0 80.5 14.3 M M
32000 -51.9 -61.4 332 60 31 6.0 3.3 23.2 73.7 11.9 M M
30000 -48.2 -54.8 334 59 30 7.5 4.1 20.6 69.0 10.2 M M
29000 -46.0 -50.8 341 57 30 7.3 4.0 19.5 67.1 9.5 M M
28000 -43.8 -46.8 348 57 29 7.3 4.0 18.6 65.4 8.9 M M
27000 -41.6 -42.9 354 57 29 7.5 4.1 17.8 64.0 8.4 M M
26000 -39.0 -38.2 355 58 30 9.1 5.0 17.3 63.2 8.1 M M
25000 -36.3 -33.3 354 58 30 9.1 5.0 17.0 62.7 8.0 M M
24000 -33.5 -28.3 354 59 30 9.2 5.1 16.9 62.4 8.0 M M
23000 -31.2 -24.2 352 59 31 7.5 4.1 16.2 61.1 7.5 M M
22000 -28.9 -20.0 351 60 31 7.6 4.2 15.4 59.7 6.9 M M
21000 -26.6 -15.9 349 61 31 8.0 4.4 14.7 58.5 6.4 M M
20000 -24.1 -11.4 349 63 32 8.6 4.7 14.2 57.6 6.0 M M
19500 -22.8 -9.0 349 64 33 8.6 4.7 14.0 57.2 5.9 M M
19000 -21.5 -6.7 349 65 33 8.6 4.7 13.8 56.9 5.8 M M
18500 -20.2 -4.4 349 66 34 8.6 4.7 13.7 56.6 5.6 M M
18000 -18.9 -2.0 350 66 34 8.6 4.7 13.5 56.2 5.5 M M
17500 -17.6 0.3 350 65 34 8.9 4.9 13.3 55.9 5.4 M M
17000 -16.2 2.8 351 63 33 5.2 2.9 12.5 54.4 4.7 M M
16500 -15.4 4.3 351 61 31 5.3 2.9 11.7 53.1 4.0 M M
16000 -14.6 5.7 350 58 30 4.8 2.6 10.9 51.7 3.4 M M
15500 -13.9 7.0 350 53 27 4.8 2.6 10.1 50.2 2.6 M M
15000 -13.2 8.2 349 49 25 5.1 2.8 9.3 48.8 1.9 M M
14500 -12.4 9.7 347 44 23 5.2 2.8 8.6 47.5 1.2 M M
14000 -11.7 10.9 345 40 20 3.5 1.9 7.8 46.1 0.5 M M
13500 -11.3 11.7 344 34 18 2.8 1.5 6.7 44.0 -0.6 448 2.3
13000 -10.9 12.4 342 29 15 2.2 1.2 5.6 42.0 -1.6 422 2.1
12500 -10.6 12.9 340 26 13 1.8 1.0 4.3 39.7 -2.9 399 2.0
12000 -10.4 13.3 337 22 11 3.3 1.8 3.0 37.5 -4.1 377 1.9
11750 -10.0 14.0 336 21 11 4.9 2.7 2.6 36.7 -4.5 359 1.8
11500 -9.7 14.5 334 19 10 4.5 2.5 2.2 36.0 -4.9 341 1.7
11250 -9.3 15.3 332 18 9 4.6 2.5 1.8 35.3 -5.3 324 1.6
11000 -9.0 15.8 329 16 8 5.4 3.0 1.4 34.6 -5.7 306 1.6
10750 -8.5 16.7 324 14 7 6.1 3.4 1.1 34.0 -6.0 285 1.4
10500 -8.1 17.4 318 12 6 5.9 3.2 0.8 33.5 -6.3 264 1.3
10250 -7.6 18.3 309 10 5 6.1 3.3 0.5 33.0 -6.6 243 1.2
10000 -7.2 19.0 301 9 5 6.5 3.6 0.3 32.5 -6.9 222 1.1
9750 -6.7 19.9 294 9 5 6.7 3.7 0.0 32.1 -7.1 199 1.0
9500 -6.2 20.8 286 9 5 6.7 3.7 -0.2 31.6 -7.4 177 0.9
9250 -5.7 21.7 279 9 5 6.7 3.7 -0.4 31.2 -7.6 154 0.8
9000 -5.2 22.6 276 10 5 6.6 3.6 -0.7 30.8 -7.9 132 0.7
8750 -4.7 23.5 275 11 6 6.8 3.7 -0.9 30.4 -8.1 110 0.6
8500 -4.2 24.4 273 12 6 6.2 3.4 -1.1 30.0 -8.4 88 0.4
8250 -4.2 24.4 273 13 6 -11.5 -6.3 -1.9 28.6 -9.1 80 0.4
8000 -5.9 21.4 271 12 6 -26.7 -14.6 -4.3 24.3 -11.6 124 0.6
7750 -7.6 18.3 270 11 6 -15.2 -8.3 -6.7 20.0 -14.0 167 0.8
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 * * * * * *
11/24/2009 AT 0800 MST | 11/24/2009 AT 1100 MST
|
K INDEX... -18.0 | K INDEX... -16.1
|
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 -58.3 -72.9 304 27 14 1.3 0.7 | -58.9 -74.0 307 26 13 0.8 0.5
45000 -56.3 -69.3 312 36 19 1.7 0.9 | -57.5 -71.5 315 37 19 1.1 0.6
40000 -58.7 -73.7 317 49 25 -1.8 -1.0 | -59.7 -75.5 308 44 23 -1.6 -0.9
38000 -59.2 -74.6 319 52 27 1.3 0.7 | -59.8 -75.6 309 46 24 2.2 1.2
36000 -58.4 -73.1 323 50 26 1.3 0.7 | -58.5 -73.3 315 47 24 2.2 1.2
34000 -57.6 -71.7 327 48 25 4.2 2.3 | -57.1 -70.8 320 47 24 5.5 3.0
32000 -53.0 -63.4 340 48 25 6.8 3.7 | -53.0 -63.4 331 42 22 6.9 3.8
30000 -48.8 -55.8 349 49 25 8.2 4.5 | -48.2 -54.8 344 39 20 7.9 4.3
29000 -46.3 -51.3 348 48 25 8.1 4.4 | -45.8 -50.4 347 41 21 7.9 4.3
28000 -43.9 -47.0 348 47 24 8.1 4.5 | -43.5 -46.3 349 42 21 7.9 4.3
27000 -41.5 -42.7 347 46 24 8.6 4.7 | -41.1 -42.0 352 43 22 8.8 4.8
26000 -38.6 -37.5 345 46 24 9.7 5.3 | -38.2 -36.8 351 43 22 9.8 5.4
25000 -35.7 -32.3 343 46 24 9.7 5.3 | -35.3 -31.5 350 42 22 9.8 5.4
24000 -32.7 -26.9 341 46 24 9.5 5.2 | -32.3 -26.1 350 42 21 9.3 5.1
23000 -30.3 -22.5 342 46 24 7.7 4.2 | -29.9 -21.8 350 41 21 7.9 4.3
22000 -28.0 -18.4 344 47 24 7.7 4.2 | -27.5 -17.5 350 41 21 7.9 4.3
21000 -25.7 -14.3 345 48 25 7.7 4.2 | -25.2 -13.4 350 41 21 8.1 4.5
20000 -23.4 -10.1 347 50 26 7.8 4.3 | -22.7 -8.9 350 41 21 8.2 4.5
19500 -22.3 -8.1 348 52 27 7.8 4.3 | -21.5 -6.7 349 42 21 8.2 4.5
19000 -21.1 -6.0 349 53 27 7.8 4.3 | -20.3 -4.5 349 42 22 8.2 4.5
18500 -19.9 -3.8 350 54 28 8.0 4.4 | -19.1 -2.4 349 42 22 8.2 4.5
18000 -18.7 -1.7 350 53 27 8.3 4.6 | -17.8 -0.0 347 42 22 8.2 4.5
17500 -17.4 0.7 350 52 27 8.3 4.5 | -16.6 2.1 346 42 22 8.2 4.5
17000 -16.2 2.8 351 51 26 8.9 4.9 | -15.4 4.3 345 42 22 8.1 4.4
16500 -14.2 6.4 352 49 25 8.7 4.8 | -13.6 7.5 345 41 21 7.7 4.2
16000 -13.0 8.6 354 49 25 7.6 4.2 | -12.6 9.3 345 39 20 6.2 3.4
15500 -11.8 10.8 356 48 25 7.9 4.3 | -11.6 11.1 346 37 19 6.3 3.5
15000 -10.8 12.6 357 48 25 5.4 2.9 | -10.8 12.6 348 35 18 5.2 2.9
14500 -10.0 14.0 358 47 24 5.5 3.0 | -10.0 14.0 350 33 17 5.3 2.9
14000 -9.1 15.6 359 45 23 5.6 3.1 | -9.1 15.6 352 31 16 6.2 3.4
13500 -8.3 17.1 357 43 22 5.7 3.1 | -8.2 17.2 353 30 15 6.3 3.4
13000 -7.5 18.5 355 40 21 4.5 2.4 | -7.3 18.9 353 29 15 6.0 3.3
12500 -6.9 19.6 353 37 19 3.9 2.1 | -6.4 20.5 351 27 14 6.0 3.3
12000 -6.4 20.5 349 33 17 2.1 1.2 | -5.5 22.1 348 25 13 4.9 2.7
11750 -6.3 20.7 347 30 16 0.8 0.4 | -5.2 22.6 345 23 12 4.4 2.4
11500 -6.2 20.8 344 27 14 1.1 0.6 | -4.9 23.2 342 22 11 4.5 2.5
11250 -6.2 20.8 341 25 13 1.1 0.6 | -4.5 23.9 339 20 10 4.6 2.5
11000 -6.0 21.2 337 22 11 2.6 1.4 | -4.2 24.4 335 18 9 5.1 2.8
10750 -5.8 21.6 333 19 10 3.7 2.0 | -3.8 25.2 330 16 8 5.4 3.0
10500 -5.5 22.1 328 17 9 3.2 1.8 | -3.4 25.9 324 14 7 5.3 2.9
10250 -5.3 22.5 321 14 7 3.9 2.2 | -3.0 26.6 317 12 6 5.5 3.0
10000 -4.9 23.2 313 12 6 5.9 3.2 | -2.5 27.5 311 11 6 6.1 3.4
9750 -4.4 24.1 307 11 6 6.7 3.7 | -2.1 28.2 307 10 5 6.2 3.4
9500 -3.9 25.0 300 11 6 6.5 3.6 | -1.6 29.1 302 9 5 6.5 3.6
9250 -3.4 25.9 292 10 5 6.7 3.7 | -1.1 30.0 296 8 4 5.2 2.8
9000 -2.9 26.8 289 10 5 7.0 3.8 | -0.9 30.4 291 8 4 3.6 1.9
8750 -2.4 27.7 287 10 5 6.9 3.8 | -0.6 30.9 287 8 4 3.7 2.0
8500 -1.9 28.6 284 10 5 7.1 3.9 | -0.4 31.3 283 8 4 3.8 2.1
8250 -1.8 28.8 282 10 5 -12.0 -6.6 | -0.1 31.8 279 8 4 6.4 3.5
8000 -3.7 25.3 280 10 5 -29.2 -16.0 | 0.5 32.9 276 7 3 8.6 4.7
7750 -5.5 22.1 278 10 5 -16.0 -8.8 | 1.0 33.8 271 6 3 7.2 3.9
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
11/24/2009 AT 1400 MST | 11/24/2009 AT 1700 MST
|
K INDEX... -10.3 | K INDEX... -8.0
|
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 -59.6 -75.3 297 22 11 1.0 0.6 | -59.6 -75.3 295 24 12 1.0 0.6
45000 -58.0 -72.4 299 29 15 1.0 0.6 | -58.0 -72.4 299 27 14 1.1 0.6
40000 -60.4 -76.7 295 43 22 -1.8 -1.0 | -60.9 -77.6 303 43 22 -2.1 -1.1
38000 -60.6 -77.1 299 45 23 2.3 1.3 | -61.2 -78.2 306 44 23 2.4 1.3
36000 -59.2 -74.6 313 41 21 2.3 1.3 | -59.7 -75.5 315 38 20 2.4 1.3
34000 -57.7 -71.9 328 40 21 5.9 3.3 | -58.1 -72.6 326 33 17 6.6 3.6
32000 -53.6 -64.5 328 36 18 6.7 3.7 | -53.8 -64.8 325 31 16 7.3 4.0
30000 -48.8 -55.8 328 32 16 8.6 4.7 | -48.7 -55.7 324 29 15 8.6 4.7
29000 -46.2 -51.2 330 32 16 8.7 4.8 | -46.1 -51.0 324 28 14 8.6 4.7
28000 -43.6 -46.5 331 31 16 8.7 4.8 | -43.5 -46.3 324 27 14 8.6 4.7
27000 -41.0 -41.8 333 31 16 9.4 5.1 | -40.9 -41.6 323 26 14 9.3 5.1
26000 -38.1 -36.6 332 30 16 9.8 5.4 | -38.0 -36.4 323 26 14 9.6 5.3
25000 -35.1 -31.2 332 30 15 9.8 5.4 | -35.1 -31.2 322 26 13 9.6 5.3
24000 -32.2 -26.0 331 29 15 9.0 4.9 | -32.2 -26.0 322 26 13 8.9 4.9
23000 -29.9 -21.8 333 29 15 7.7 4.2 | -29.8 -21.6 323 26 13 8.0 4.4
22000 -27.6 -17.7 335 29 15 7.7 4.2 | -27.4 -17.3 323 26 14 8.0 4.4
21000 -25.2 -13.4 336 30 15 8.4 4.6 | -25.0 -13.0 324 27 14 8.8 4.8
20000 -22.7 -8.9 337 31 16 8.5 4.6 | -22.3 -8.1 327 27 14 8.8 4.8
19500 -21.5 -6.7 338 32 16 8.5 4.6 | -21.0 -5.8 328 28 14 8.8 4.8
19000 -20.2 -4.4 338 33 17 8.5 4.6 | -19.7 -3.5 329 28 15 8.8 4.8
18500 -18.9 -2.0 338 33 17 8.6 4.7 | -18.4 -1.1 330 29 15 8.5 4.7
18000 -17.6 0.3 338 34 17 8.7 4.8 | -17.1 1.2 330 29 15 8.4 4.6
17500 -16.4 2.5 337 34 18 8.6 4.7 | -15.9 3.4 330 29 15 8.5 4.7
17000 -15.1 4.8 336 34 18 8.3 4.5 | -14.6 5.7 331 29 15 8.9 4.9
16500 -13.9 7.0 335 34 17 8.4 4.6 | -12.6 9.3 331 29 15 8.5 4.7
16000 -12.1 10.2 333 32 17 7.2 4.0 | -11.4 11.5 331 29 15 8.0 4.4
15500 -11.1 12.0 332 31 16 7.3 4.0 | -10.2 13.6 330 29 15 8.0 4.4
15000 -10.0 14.0 330 30 15 6.4 3.5 | -9.0 15.8 330 28 15 7.7 4.2
14500 -9.1 15.6 329 27 14 6.5 3.6 | -7.9 17.8 330 28 14 7.8 4.3
14000 -8.1 17.4 328 25 13 6.5 3.5 | -6.8 19.8 330 27 14 6.7 3.6
13500 -7.1 19.2 327 23 12 6.5 3.6 | -5.8 21.6 330 25 13 6.8 3.7
13000 -6.2 20.8 326 21 11 6.2 3.4 | -4.9 23.2 329 24 12 5.4 2.9
12500 -5.2 22.6 324 20 10 6.2 3.4 | -4.1 24.6 329 22 11 5.2 2.9
12000 -4.3 24.3 322 18 10 5.9 3.2 | -3.4 25.9 328 20 10 4.9 2.7
11750 -3.9 25.0 319 17 9 5.8 3.2 | -3.0 26.6 326 18 9 4.8 2.6
11500 -3.5 25.7 316 16 8 5.8 3.2 | -2.7 27.1 323 17 9 4.8 2.6
11250 -3.0 26.6 312 15 8 5.7 3.1 | -2.3 27.9 321 16 8 4.8 2.6
11000 -2.6 27.3 309 14 7 5.5 3.0 | -2.0 28.4 317 14 7 4.7 2.6
10750 -2.2 28.0 305 13 7 5.5 3.0 | -1.7 28.9 313 13 7 4.7 2.6
10500 -1.8 28.8 302 12 6 5.6 3.0 | -1.4 29.5 308 13 6 4.7 2.6
10250 -1.4 29.5 298 12 6 5.5 3.0 | -1.0 30.2 302 12 6 5.0 2.7
10000 -1.1 30.0 295 11 5 5.5 3.0 | -0.7 30.7 298 11 6 5.4 3.0
9750 -0.7 30.7 292 10 5 5.5 3.0 | -0.3 31.5 294 10 5 5.4 3.0
9500 -0.3 31.5 289 9 4 5.5 3.0 | 0.1 32.2 289 9 5 5.7 3.1
9250 0.1 32.2 286 8 4 6.0 3.3 | 0.4 32.7 284 8 4 4.9 2.7
9000 0.5 32.9 285 6 3 6.5 3.6 | 0.7 33.3 279 7 4 4.0 2.2
8750 1.0 33.8 284 5 3 6.5 3.6 | 1.0 33.8 273 6 3 4.2 2.3
8500 1.4 34.5 283 4 2 6.6 3.6 | 1.3 34.3 262 4 2 3.9 2.2
8250 2.0 35.6 283 3 1 8.8 4.8 | 1.5 34.7 249 3 2 -0.9 -0.5
8000 2.7 36.9 285 2 1 10.7 5.9 | 1.2 34.2 244 3 1 -4.9 -2.7
7750 3.4 38.1 289 2 1 9.4 5.2 | 0.9 33.6 234 2 1 -1.9 -1.0
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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