116
UXUS97 KPUB 131236
SRGPUB
SOARING FORECAST
NATIONAL WEATHER SERVICE PUEBLO, COLORADO
0636 MDT THURSDAY, MARCH 13, 2025
THIS FORECAST IS FOR THE AIR FORCE ACADEMY FOR THURSDAY, MARCH 13, 2025:
IF THE TRIGGER TEMPERATURE OF 52.6 F/11.4 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 819 FT/MIN (4.2 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 17762 FT MSL (10147 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 63.0 F/17.7 C
TIME OF TRIGGER TEMPERATURE.................... 1030 MDT
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................. 13441 FT MSL (5826 FT AGL)
THERMAL SOARING OUTLOOK FOR FRIDAY 03/14....... EXCELLENT
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 07:12:42 / 19:04:27 MDT
TOTAL POSSIBLE SUNSHINE........... 11 HR 51 MIN 44 SEC (711 MIN 44 SEC)
ALTITUDE OF SUN AT 13:08:34 MDT... 48.37 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 03/13/2025 AT 0600 MDT
FREEZING LEVEL.................. 10589 FT MSL (2974 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 18267 FT MSL (10652 FT AGL)
LIFTED CONDENSATION LEVEL....... 18428 FT MSL (10812 FT AGL)
LIFTED INDEX.................... -0.3
K INDEX......................... -24.6
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 -60.9 -77.6 260 50 26 0.5 0.3 M M M M M
45000 -60.1 -76.2 255 71 37 0.6 0.3 M M M M M
40000 -58.7 -73.7 260 71 37 0.9 0.5 M M M M M
38000 -57.7 -71.9 255 67 35 3.0 1.7 M M M M M
36000 -55.6 -68.1 255 58 30 3.0 1.7 M M M M M
34000 -53.2 -63.8 250 51 26 8.8 4.8 M M M M M
32000 -48.0 -54.4 250 50 26 8.6 4.7 M M M M M
30000 -43.0 -45.4 250 48 25 7.7 4.2 25.5 77.9 6.4 M M
29000 -40.7 -41.3 250 47 24 7.7 4.2 24.6 76.3 5.8 M M
28000 -38.4 -37.1 250 46 24 7.7 4.2 23.8 74.9 5.2 M M
27000 -36.1 -33.0 250 45 23 7.6 4.2 23.2 73.8 4.8 M M
26000 -33.9 -29.0 250 43 22 7.4 4.1 22.2 72.0 4.1 M M
25000 -31.6 -24.9 250 42 21 7.4 4.1 21.3 70.4 3.4 M M
24000 -29.4 -20.9 245 40 21 7.3 4.0 20.6 69.1 2.8 M M
23000 -27.0 -16.6 245 38 20 8.2 4.5 19.9 67.8 2.2 M M
22000 -24.0 -11.2 245 37 19 8.2 4.5 19.2 66.6 1.7 M M
21000 -21.5 -6.7 245 35 18 8.2 4.5 18.7 65.7 1.3 M M
20000 -19.1 -2.4 240 35 18 8.1 4.5 18.1 64.6 0.7 M M
19500 -17.9 -0.2 240 34 18 8.2 4.5 17.8 64.1 0.5 M M
19000 -16.6 2.1 240 34 18 8.2 4.5 17.6 63.6 0.3 M M
18500 -15.4 4.3 240 34 17 8.8 4.8 17.4 63.3 0.1 M M
18000 -14.0 6.8 235 33 17 9.2 5.0 17.3 63.1 0.0 M M
17500 -12.6 9.3 235 33 17 9.2 5.0 17.2 62.9 -0.0 883 4.5
17000 -11.4 11.5 230 33 17 7.7 4.2 16.9 62.5 -0.3 831 4.2
16500 -10.2 13.6 230 32 16 7.9 4.3 16.6 61.9 -0.6 781 4.0
16000 -9.1 15.6 225 31 16 7.4 4.1 16.3 61.3 -0.9 732 3.7
15500 -8.0 17.6 225 30 15 7.3 4.0 15.9 60.6 -1.3 685 3.5
15000 -6.9 19.6 220 29 15 7.2 4.0 15.5 59.9 -1.6 638 3.2
14500 -5.9 21.4 215 29 15 7.1 3.9 15.0 59.1 -2.1 592 3.0
14000 -4.8 23.4 215 29 15 7.1 3.9 14.6 58.3 -2.5 546 2.8
13500 -3.8 25.2 215 28 14 7.3 4.0 14.2 57.5 -2.9 499 2.5
13000 -2.7 27.1 220 27 14 8.3 4.6 13.8 56.8 -3.4 453 2.3
12500 -1.6 29.1 225 25 13 4.4 2.4 13.4 56.2 -3.8 406 2.1
12000 -1.1 30.0 235 24 12 3.4 1.9 12.4 54.4 -4.7 376 1.9
11750 -0.9 30.4 240 23 12 4.4 2.4 12.0 53.5 -5.2 361 1.8
11500 -0.6 30.9 240 24 12 3.4 1.9 11.6 52.8 -5.7 344 1.7
11250 -0.4 31.3 245 25 13 1.5 0.8 10.9 51.7 -6.3 333 1.7
11000 -0.3 31.5 250 26 13 1.5 0.8 10.3 50.6 -6.9 323 1.6
10750 -0.2 31.6 255 27 14 2.7 1.5 9.7 49.4 -7.6 312 1.6
10500 0.0 32.0 260 30 16 4.3 2.3 9.2 48.6 -8.1 297 1.5
10250 0.3 32.5 265 34 17 3.0 1.6 8.8 47.8 -8.6 282 1.4
10000 0.4 32.7 265 35 18 2.1 1.1 8.2 46.7 -9.2 271 1.4
9750 0.5 32.9 265 37 19 2.9 1.6 7.6 45.7 -9.8 259 1.3
9500 0.8 33.4 265 35 18 3.2 1.8 7.1 44.8 -10.4 245 1.2
9250 1.0 33.8 265 33 17 3.6 2.0 6.6 43.9 -10.9 231 1.2
9000 1.3 34.3 265 30 16 4.5 2.5 6.2 43.2 -11.4 216 1.1
8750 1.6 34.9 265 28 14 4.3 2.4 5.8 42.4 -11.8 199 1.0
8500 1.9 35.4 265 26 13 3.1 1.7 5.3 41.6 -12.3 183 0.9
8250 2.1 35.8 265 24 12 5.9 3.2 4.9 40.8 -12.8 167 0.8
8000 2.6 36.7 265 22 11 1.4 0.8 4.6 40.3 -13.1 147 0.7
7750 2.0 35.6 265 15 8 -18.4 -10.1 3.3 37.9 -14.5 157 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 * * * * * *
03/13/2025 AT 0900 MDT | 03/13/2025 AT 1200 MDT
|
CAPE... 0.0 LI... +2.2 | CAPE... 0.0 LI... +2.3
CINH... 0.0 K INDEX... -13.1 | CINH... 0.0 K INDEX... -10.2
|
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 -58.5 -73.3 255 57 29 1.0 0.5 | -58.3 -72.9 260 53 27 2.1 1.1
45000 -57.0 -70.6 250 78 40 1.0 0.5 | -55.2 -67.4 250 79 40 2.7 1.5
40000 -59.3 -74.7 250 81 42 -1.6 -0.9 | -58.5 -73.3 245 79 41 -2.4 -1.3
38000 -59.0 -74.2 250 77 39 4.1 2.3 | -58.8 -73.8 245 77 40 3.4 1.9
36000 -56.3 -69.3 240 64 33 4.1 2.2 | -56.5 -69.7 240 72 37 3.4 1.9
34000 -53.4 -64.1 235 55 28 8.7 4.8 | -54.0 -65.2 230 69 35 9.3 5.1
32000 -48.4 -55.1 235 55 28 8.4 4.6 | -48.8 -55.8 230 66 34 8.7 4.8
30000 -43.3 -45.9 240 55 28 8.3 4.6 | -43.6 -46.5 230 64 33 8.1 4.4
29000 -40.8 -41.4 240 54 28 8.3 4.6 | -41.2 -42.2 230 63 32 8.2 4.5
28000 -38.3 -36.9 240 53 27 8.3 4.6 | -38.7 -37.7 235 62 32 8.2 4.5
27000 -35.8 -32.4 240 52 27 8.3 4.5 | -36.3 -33.3 235 61 32 8.3 4.5
26000 -33.6 -28.5 240 51 26 7.4 4.0 | -33.9 -29.0 235 59 30 7.6 4.1
25000 -31.4 -24.5 235 49 25 7.4 4.1 | -31.7 -25.1 235 56 29 7.6 4.1
24000 -29.2 -20.6 235 48 25 7.4 4.1 | -29.4 -20.9 235 54 28 7.6 4.2
23000 -26.9 -16.4 235 46 24 7.4 4.1 | -27.2 -17.0 235 50 26 7.1 3.9
22000 -24.2 -11.6 235 44 22 7.4 4.1 | -24.6 -12.3 230 45 23 7.1 3.9
21000 -22.0 -7.6 235 41 21 7.6 4.2 | -22.5 -8.5 230 41 21 7.2 4.0
20000 -19.7 -3.5 235 38 20 7.6 4.2 | -20.3 -4.5 230 40 21 7.3 4.0
19500 -18.5 -1.3 235 37 19 7.6 4.2 | -19.2 -2.6 230 39 20 7.3 4.0
19000 -17.4 0.7 235 35 18 7.6 4.2 | -18.1 -0.6 230 39 20 7.3 4.0
18500 -16.2 2.8 235 34 17 7.4 4.0 | -17.0 1.4 230 38 20 7.3 4.0
18000 -15.2 4.6 235 33 17 7.1 3.9 | -15.9 3.4 235 37 19 7.3 4.0
17500 -14.1 6.6 235 33 17 7.0 3.8 | -14.8 5.4 235 36 18 7.3 4.0
17000 -13.0 8.6 240 32 17 8.2 4.5 | -13.7 7.3 235 34 18 7.8 4.3
16500 -11.8 10.8 235 32 16 8.0 4.4 | -12.5 9.5 230 33 17 7.8 4.3
16000 -10.6 12.9 235 31 16 8.5 4.7 | -11.3 11.7 230 32 16 7.6 4.2
15500 -9.3 15.3 235 31 16 8.6 4.7 | -10.2 13.6 225 31 16 7.5 4.1
15000 -8.0 17.6 230 31 16 8.2 4.5 | -9.1 15.6 225 30 16 7.5 4.1
14500 -6.8 19.8 225 29 15 7.3 4.0 | -8.0 17.6 220 29 15 7.4 4.1
14000 -5.8 21.6 215 27 14 7.3 4.0 | -6.9 19.6 210 27 14 7.2 4.0
13500 -4.7 23.5 215 25 13 7.0 3.9 | -5.6 21.9 210 26 13 9.7 5.3
13000 -3.6 25.5 220 22 11 6.6 3.6 | -4.2 24.4 210 25 13 10.8 5.9
12500 -2.4 27.7 220 19 10 7.8 4.3 | -3.6 25.5 225 24 12 0.7 0.4
12000 -1.6 29.1 220 16 8 5.1 2.8 | -3.0 26.6 235 25 13 3.8 2.1
11750 -1.2 29.8 225 15 8 6.9 3.8 | -2.7 27.1 240 25 13 4.3 2.3
11500 -0.7 30.7 230 15 8 6.7 3.7 | -2.5 27.5 245 24 12 5.4 3.0
11250 -0.3 31.5 235 16 8 4.3 2.4 | -2.1 28.2 245 22 11 6.2 3.4
11000 0.0 32.0 240 16 8 4.8 2.6 | -1.7 28.9 250 20 10 6.0 3.3
10750 0.4 32.7 245 17 9 4.9 2.7 | -1.2 29.8 250 18 9 6.5 3.6
10500 0.8 33.4 255 20 10 5.3 2.9 | -0.8 30.6 250 15 8 7.4 4.1
10250 1.1 34.0 255 22 11 3.3 1.8 | -0.2 31.6 245 14 7 9.2 5.0
10000 1.2 34.2 260 24 12 1.8 1.0 | 0.6 33.1 245 13 7 10.0 5.5
9750 1.3 34.3 265 26 13 2.5 1.4 | 1.3 34.3 240 12 6 9.9 5.5
9500 1.5 34.7 265 26 14 2.7 1.5 | 2.1 35.8 240 12 6 10.3 5.6
9250 1.7 35.1 265 26 14 2.7 1.5 | 2.8 37.0 240 11 6 10.3 5.6
9000 1.8 35.2 265 25 13 2.5 1.4 | 3.6 38.5 235 11 6 10.1 5.6
8750 2.0 35.6 265 23 12 3.6 2.0 | 4.4 39.9 235 11 6 10.4 5.7
8500 2.3 36.1 265 21 11 4.7 2.6 | 5.2 41.4 235 10 5 10.9 6.0
8250 2.6 36.7 260 20 10 4.2 2.3 | 6.0 42.8 235 10 5 10.5 5.8
8000 2.9 37.2 260 18 9 7.5 4.1 | 6.7 44.1 235 10 5 10.3 5.7
7750 3.7 38.7 255 13 6 14.0 7.7 | 7.7 45.9 230 9 4 17.4 9.6
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
03/13/2025 AT 1500 MDT | 03/13/2025 AT 1800 MDT
|
CAPE... +9.4 LI... +0.5 | CAPE... +13.3 LI... +0.1
CINH... -0.0 K INDEX... +6.3 | CINH... -6.7 K INDEX... +10.8
|
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 -58.0 -72.4 255 49 25 1.7 1.0 | -57.4 -71.3 255 43 22 3.5 1.9
45000 -55.4 -67.7 250 75 39 2.0 1.1 | -52.2 -62.0 245 64 33 3.7 2.1
40000 -56.7 -70.1 240 77 40 -1.1 -0.6 | -54.5 -66.1 235 71 36 -1.9 -1.1
38000 -56.6 -69.9 235 77 40 2.8 1.6 | -55.1 -67.2 230 72 37 1.6 0.9
36000 -54.7 -66.5 235 75 39 2.9 1.6 | -54.1 -65.4 230 68 35 1.6 0.9
34000 -52.8 -63.0 235 74 38 5.3 2.9 | -53.1 -63.6 235 64 33 2.9 1.6
32000 -49.2 -56.6 230 69 35 6.0 3.3 | -50.1 -58.2 230 58 30 5.2 2.9
30000 -45.5 -49.9 225 64 33 8.2 4.5 | -46.9 -52.4 225 52 27 6.8 3.7
29000 -43.0 -45.4 225 62 32 8.5 4.7 | -44.5 -48.1 225 52 27 8.3 4.5
28000 -40.4 -40.7 225 60 31 8.5 4.7 | -42.0 -43.6 225 52 27 8.3 4.6
27000 -37.9 -36.2 225 58 30 8.5 4.7 | -39.5 -39.1 225 52 27 8.3 4.6
26000 -35.4 -31.7 225 57 30 8.4 4.6 | -37.0 -34.6 225 52 27 8.3 4.5
25000 -32.8 -27.0 225 57 29 8.4 4.6 | -34.5 -30.1 225 51 26 8.3 4.5
24000 -30.3 -22.5 225 57 29 8.4 4.6 | -32.1 -25.8 225 51 26 8.3 4.5
23000 -28.0 -18.4 230 56 29 7.4 4.1 | -29.6 -21.3 225 50 26 7.9 4.3
22000 -25.2 -13.4 230 56 29 7.4 4.1 | -27.3 -17.1 230 50 25 7.9 4.3
21000 -23.0 -9.4 230 56 29 7.2 3.9 | -24.3 -11.7 230 49 25 7.9 4.3
20000 -21.0 -5.8 235 53 27 6.6 3.6 | -22.2 -8.0 235 48 24 7.0 3.8
19500 -20.0 -4.0 235 51 26 6.6 3.6 | -21.1 -6.0 240 47 24 7.0 3.8
19000 -19.0 -2.2 240 50 26 6.6 3.6 | -20.1 -4.2 240 46 24 7.0 3.8
18500 -18.1 -0.6 240 49 25 6.6 3.6 | -19.1 -2.4 240 45 23 7.0 3.8
18000 -17.0 1.4 240 46 24 7.3 4.0 | -18.0 -0.4 245 44 22 6.9 3.8
17500 -15.9 3.4 245 44 22 7.3 4.0 | -17.0 1.4 245 41 21 6.9 3.8
17000 -14.8 5.4 245 41 21 7.7 4.2 | -16.0 3.2 245 39 20 7.5 4.1
16500 -13.7 7.3 245 37 19 7.8 4.3 | -14.8 5.4 250 35 18 8.1 4.5
16000 -12.5 9.5 245 34 18 7.3 4.0 | -13.6 7.5 250 31 16 8.2 4.5
15500 -11.6 11.1 240 29 15 6.0 3.3 | -12.3 9.9 245 27 14 8.7 4.8
15000 -10.8 12.6 240 24 12 6.0 3.3 | -11.1 12.0 245 24 12 8.8 4.8
14500 -9.7 14.5 240 20 10 8.9 4.9 | -9.8 14.4 240 22 11 8.3 4.6
14000 -8.5 16.7 240 16 8 8.6 4.7 | -8.6 16.5 235 22 11 8.4 4.6
13500 -7.2 19.0 240 14 7 9.6 5.3 | -7.5 18.5 235 23 12 7.5 4.1
13000 -5.7 21.7 235 13 7 9.6 5.3 | -6.4 20.5 230 22 12 7.4 4.1
12500 -4.3 24.3 230 12 6 9.1 5.0 | -4.6 23.7 225 23 12 12.2 6.7
12000 -2.9 26.8 225 12 6 8.8 4.8 | -3.3 26.1 225 23 12 8.3 4.6
11750 -2.2 28.0 220 12 6 11.6 6.4 | -2.7 27.1 220 23 12 10.2 5.6
11500 -1.3 29.7 215 12 6 11.4 6.2 | -1.9 28.6 220 23 12 11.1 6.1
11250 -0.6 30.9 210 11 6 8.4 4.6 | -1.1 30.0 220 23 12 9.3 5.1
11000 0.0 32.0 210 11 6 9.2 5.0 | -0.4 31.3 215 23 12 9.6 5.3
10750 0.7 33.3 205 11 6 8.9 4.9 | 0.3 32.5 215 23 12 9.7 5.3
10500 1.4 34.5 205 11 6 9.2 5.1 | 1.0 33.8 210 23 12 9.1 5.0
10250 2.1 35.8 200 11 6 9.7 5.3 | 1.7 35.1 210 23 12 9.3 5.1
10000 2.8 37.0 200 11 6 9.8 5.4 | 2.4 36.3 205 23 12 10.0 5.5
9750 3.6 38.5 200 11 6 9.8 5.4 | 3.1 37.6 205 23 12 9.8 5.4
9500 4.3 39.7 195 11 6 10.5 5.7 | 3.9 39.0 200 22 12 9.8 5.4
9250 5.1 41.2 195 11 6 10.4 5.7 | 4.6 40.3 200 22 11 9.8 5.4
9000 5.9 42.6 195 11 6 9.8 5.4 | 5.3 41.5 195 22 11 10.0 5.5
8750 6.6 43.9 190 11 6 10.1 5.5 | 6.1 43.0 195 22 11 10.0 5.5
8500 7.4 45.3 190 11 6 10.8 5.9 | 6.8 44.2 195 22 11 9.8 5.4
8250 8.2 46.8 190 11 6 11.5 6.3 | 7.6 45.7 195 21 11 9.8 5.4
8000 9.0 48.2 190 11 6 8.5 4.7 | 8.3 46.9 190 21 11 9.3 5.1
7750 12.3 54.1 190 10 5 72.7 39.9 | 9.0 48.2 190 20 10 10.2 5.6
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 TWICE PER DAY, ONCE 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 RAWINSONDE OBSERVATION AND/OR
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.
DEFINITIONS:
CAPE (CONVECTIVE AVAILABLE POTENTIAL ENERGY) - AN INTEGRATED MEASURE OF THE
ENERGY AVAILABLE FOR CONVECTIVE DEVELOPMENT, ALSO KNOWN AS THE POSITIVE
AREA ON A THERMODYNAMIC DIAGRAM. UNITS ARE JOULES PER KILOGRAM. LARGER
VALUES ARE INDICATIVE OF GREATER INSTABILITY AND THE POSSIBILITY OF
STRONGER CONVECTIVE ACTIVITY, INCLUDING THUNDERSTORMS. VALUES AROUND OR
GREATER THAN 1000 SUGGEST THE POSSIBILITY OF SEVERE WEATHER SHOULD
CONVECTIVE ACTIVITY DEVELOP.
CIN (CONVECTIVE INHIBITION) - AN INTEGRATED MEASURE OF THE AMOUNT OF ENERGY
NEEDED TO INITIATE CONVECTIVE ACTIVITY, ALSO KNOWN AS THE NEGATIVE AREA ON
A THERMODYNAMIC DIAGRAM. UNITS ARE JOULES PER KILOGRAM. THE MORE NEGATIVE
THIS NUMBER, THE MORE ENERGY IS REQUIRED TO INITIATE CONVECTION. THIS
INHIBITIVE ENERGY CAN BE OVERCOME THROUGH SURFACE HEATING, COOLING ALOFT,
LIFTING MECHANISMS (OROGRAPHIC, FRONTAL, GRAVITY WAVES, ETC.)
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 (LI) - 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, CIRROSTRATUS, 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.
042613
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