705  
UXUS97 KPUB 041339  
SRGPUB  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE PUEBLO, COLORADO  
0638 MST MONDAY, MARCH 4, 2024  
 
THIS FORECAST IS FOR THE AIR FORCE ACADEMY FOR MONDAY, MARCH 4, 2024:  
 
IF THE TRIGGER TEMPERATURE OF 38.9 F/3.8 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... GOOD  
MAXIMUM RATE OF LIFT........................ 610 FT/MIN (3.1 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 15123 FT MSL (7522 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 49.0 F/9.9 C  
TIME OF TRIGGER TEMPERATURE.................... 1045 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................. 13852 FT MSL (6251 FT AGL)  
THERMAL SOARING OUTLOOK FOR TUESDAY 03/05...... FAIR  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 06:26:04 / 17:55:31 MST  
TOTAL POSSIBLE SUNSHINE........... 11 HR 29 MIN 26 SEC (689 MIN 26 SEC)  
ALTITUDE OF SUN AT 12:10:48 MST... 44.92 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 03/04/2024 AT 0500 MST  
 
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C  
CONVECTIVE CONDENSATION LEVEL... 16222 FT MSL (8621 FT AGL)  
LIFTED CONDENSATION LEVEL....... 15615 FT MSL (8014 FT AGL)  
LIFTED INDEX.................... +3.2  
K INDEX......................... -16.3  
 
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 -57.2 -71.0 260 73 38 0.9 0.5 M M M M M  
45000 -55.8 -68.4 255 81 41 0.9 0.5 M M M M M  
40000 -55.2 -67.4 250 74 38 0.3 0.2 M M M M M  
38000 -55.0 -67.0 245 73 38 0.4 0.2 M M M M M  
36000 -54.7 -66.5 245 76 39 0.4 0.2 M M M M M  
34000 -54.5 -66.1 240 80 41 1.5 0.8 M M M M M  
32000 -50.9 -59.6 240 77 40 6.3 3.5 M M M M M  
30000 -47.1 -52.8 240 74 38 6.9 3.8 M M M M M  
29000 -44.7 -48.5 240 72 37 8.0 4.4 21.0 69.8 9.0 M M  
28000 -42.3 -44.1 245 70 36 8.0 4.4 20.3 68.5 8.5 M M  
27000 -39.9 -39.8 245 68 35 8.0 4.4 19.7 67.4 8.1 M M  
26000 -37.5 -35.5 245 67 34 8.6 4.7 19.1 66.4 7.8 M M  
25000 -34.9 -30.8 250 68 35 8.6 4.7 18.6 65.5 7.5 M M  
24000 -32.3 -26.1 250 68 35 8.6 4.7 18.3 64.9 7.3 M M  
23000 -29.3 -20.7 250 69 35 7.6 4.2 17.5 63.6 6.8 M M  
22000 -27.0 -16.6 250 69 36 7.6 4.2 16.7 62.1 6.2 M M  
21000 -24.7 -12.5 250 69 36 7.6 4.2 16.1 60.9 5.7 M M  
20000 -22.4 -8.3 250 68 35 7.5 4.1 15.2 59.4 5.0 M M  
19500 -21.3 -6.3 250 66 34 7.5 4.1 14.8 58.7 4.7 M M  
19000 -20.2 -4.4 250 65 34 7.5 4.1 14.5 58.0 4.4 M M  
18500 -19.0 -2.2 250 64 33 7.6 4.2 14.1 57.4 4.1 M M  
18000 -18.0 -0.4 250 60 31 6.6 3.6 13.7 56.6 3.8 M M  
17500 -17.0 1.4 245 52 27 6.6 3.6 13.2 55.7 3.3 M M  
17000 -16.0 3.2 240 44 23 6.1 3.3 12.7 54.8 2.9 M M  
16500 -15.2 4.6 240 40 21 5.6 3.1 11.9 53.5 2.2 M M  
16000 -14.3 6.3 240 36 18 5.4 3.0 11.3 52.3 1.6 M M  
15500 -13.8 7.2 245 39 20 3.0 1.7 10.3 50.6 0.7 M M  
15000 -13.3 8.1 255 46 24 3.4 1.9 9.2 48.6 -0.3 603 3.1  
14500 -12.9 8.8 260 52 27 1.8 1.0 8.1 46.6 -1.4 577 2.9  
14000 -12.7 9.1 260 54 28 1.6 0.9 6.8 44.3 -2.6 555 2.8  
13500 -12.2 10.0 260 55 28 6.5 3.6 5.8 42.4 -3.6 527 2.7  
13000 -11.2 11.8 260 52 27 8.6 4.7 5.4 41.7 -4.1 480 2.4  
12500 -10.6 12.9 260 48 25 3.7 2.0 4.5 40.1 -5.0 450 2.3  
12000 -9.3 15.3 260 44 23 8.5 4.7 4.3 39.8 -5.2 396 2.0  
11750 -8.7 16.3 260 42 22 9.0 4.9 4.3 39.7 -5.3 369 1.9  
11500 -8.0 17.6 260 40 21 8.3 4.5 4.2 39.6 -5.4 342 1.7  
11250 -7.5 18.5 255 38 19 7.4 4.1 4.0 39.3 -5.6 317 1.6  
11000 -6.9 19.6 255 35 18 7.5 4.1 3.9 38.9 -5.8 294 1.5  
10750 -6.4 20.5 255 33 17 6.8 3.7 3.7 38.6 -6.0 270 1.4  
10500 -6.0 21.2 250 30 15 3.0 1.6 3.3 38.0 -6.4 251 1.3  
10250 -5.8 21.6 250 26 13 2.8 1.5 2.7 36.9 -7.0 239 1.2  
10000 -5.5 22.1 245 22 12 5.4 3.0 2.3 36.2 -7.4 222 1.1  
9750 -5.2 22.6 240 20 10 3.6 2.0 1.9 35.5 -7.8 204 1.0  
9500 -5.0 23.0 235 16 8 0.7 0.4 1.3 34.4 -8.4 191 1.0  
9250 -5.0 23.0 225 13 6 0.2 0.1 0.6 33.1 -9.1 183 0.9  
9000 -4.9 23.2 210 10 5 1.6 0.9 -0.1 31.9 -9.8 174 0.9  
8750 -4.8 23.4 185 8 4 1.3 0.7 -0.7 30.8 -10.4 162 0.8  
8500 -4.7 23.5 170 7 4 0.5 0.3 -1.4 29.5 -11.1 153 0.8  
8250 -4.6 23.7 150 7 4 0.5 0.3 -2.1 28.3 -11.8 144 0.7  
8000 -4.5 23.9 130 7 4 2.6 1.4 -2.7 27.1 -12.5 133 0.7  
7750 -4.2 24.4 115 8 4 5.1 2.8 -3.1 26.4 -12.9 117 0.6  
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 * * * * * *  
 
03/04/2024 AT 0800 MST | 03/04/2024 AT 1100 MST  
|  
CAPE... 0.0 LI... +6.2 | CAPE... 0.0 LI... +4.9  
CINH... 0.0 K INDEX... -20.9 | CINH... 0.0 K INDEX... -21.5  
|  
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 -56.3 -69.3 260 66 34 0.9 0.5 | -56.2 -69.2 255 66 34 1.3 0.7  
45000 -54.9 -66.8 260 76 39 0.9 0.5 | -54.3 -65.7 255 75 39 1.2 0.7  
40000 -55.9 -68.6 245 75 39 -0.8 -0.5 | -56.3 -69.3 245 76 39 -1.6 -0.9  
38000 -56.1 -69.0 240 75 39 0.8 0.5 | -56.9 -70.4 245 75 39 0.7 0.4  
36000 -55.6 -68.1 235 74 38 0.9 0.5 | -56.4 -69.5 240 71 36 0.8 0.4  
34000 -55.1 -67.2 230 73 38 1.6 0.9 | -56.0 -68.8 230 67 35 1.5 0.8  
32000 -51.3 -60.3 230 73 38 6.7 3.7 | -52.1 -61.8 235 65 34 6.9 3.8  
30000 -47.3 -53.1 235 73 38 7.1 3.9 | -47.9 -54.2 235 64 33 7.2 4.0  
29000 -45.0 -49.0 235 71 36 7.7 4.2 | -45.6 -50.1 235 64 33 7.8 4.3  
28000 -42.6 -44.7 235 68 35 7.7 4.2 | -43.2 -45.8 240 64 33 7.8 4.3  
27000 -40.3 -40.5 235 65 33 7.8 4.3 | -40.9 -41.6 240 64 33 7.9 4.3  
26000 -37.9 -36.2 235 63 32 8.8 4.8 | -38.3 -36.9 240 63 33 9.4 5.1  
25000 -35.2 -31.4 240 63 32 8.8 4.8 | -34.8 -30.6 240 63 32 9.4 5.1  
24000 -31.9 -25.4 245 64 33 8.9 4.9 | -32.0 -25.6 245 62 32 9.4 5.2  
23000 -29.4 -20.9 250 66 34 8.1 4.4 | -29.4 -20.9 250 63 33 8.1 4.4  
22000 -27.0 -16.6 250 68 35 8.0 4.4 | -27.0 -16.6 250 65 33 8.1 4.4  
21000 -24.5 -12.1 255 71 36 8.1 4.4 | -24.6 -12.3 255 67 34 8.0 4.4  
20000 -22.3 -8.1 255 69 35 7.4 4.0 | -22.3 -8.1 255 65 33 7.5 4.1  
19500 -21.2 -6.2 255 67 35 7.4 4.0 | -21.2 -6.2 260 63 33 7.5 4.1  
19000 -20.1 -4.2 255 66 34 7.4 4.0 | -20.1 -4.2 260 62 32 7.5 4.1  
18500 -19.0 -2.2 250 64 33 7.5 4.1 | -18.9 -2.0 260 60 31 7.5 4.1  
18000 -17.9 -0.2 250 62 32 5.9 3.2 | -17.8 -0.0 260 59 30 7.3 4.0  
17500 -17.0 1.4 250 57 29 5.9 3.2 | -16.7 1.9 260 58 30 7.3 4.0  
17000 -16.2 2.8 250 53 27 5.3 2.9 | -15.6 3.9 265 57 30 6.5 3.5  
16500 -15.5 4.1 250 46 24 4.7 2.6 | -14.8 5.4 260 56 29 5.7 3.1  
16000 -14.8 5.4 250 40 21 4.6 2.5 | -13.9 7.0 255 54 28 5.7 3.1  
15500 -14.3 6.3 255 39 20 2.4 1.3 | -13.0 8.6 250 52 27 6.6 3.6  
15000 -13.9 7.0 260 43 22 2.6 1.4 | -12.0 10.4 250 50 26 6.8 3.7  
14500 -13.5 7.7 265 47 24 2.7 1.5 | -11.2 11.8 250 49 25 3.5 1.9  
14000 -13.2 8.2 270 50 26 2.7 1.5 | -10.7 12.7 260 52 27 3.8 2.1  
13500 -12.7 9.1 270 52 27 4.3 2.4 | -10.4 13.3 265 54 28 -0.8 -0.4  
13000 -12.0 10.4 265 48 25 3.8 2.1 | -10.7 12.7 265 50 26 -1.2 -0.7  
12500 -11.0 12.2 265 45 23 9.0 4.9 | -11.1 12.0 265 44 23 1.6 0.9  
12000 -10.1 13.8 265 41 21 6.2 3.4 | -10.5 13.1 260 36 19 4.2 2.3  
11750 -9.7 14.5 260 39 20 5.8 3.2 | -10.2 13.6 260 33 17 4.6 2.5  
11500 -9.3 15.3 260 36 19 4.9 2.7 | -9.9 14.2 255 30 15 3.8 2.1  
11250 -9.0 15.8 255 33 17 4.5 2.5 | -9.6 14.7 250 28 14 2.6 1.4  
11000 -8.6 16.5 255 31 16 5.2 2.8 | -9.4 15.1 250 26 13 2.3 1.2  
10750 -8.2 17.2 250 29 15 4.1 2.3 | -9.3 15.3 245 24 12 2.7 1.5  
10500 -8.1 17.4 245 26 13 0.1 0.1 | -9.0 15.8 235 22 11 2.6 1.4  
10250 -8.1 17.4 235 23 12 -0.6 -0.3 | -8.8 16.2 220 19 10 5.5 3.0  
10000 -8.1 17.4 230 21 11 1.4 0.8 | -8.2 17.2 210 18 9 8.3 4.6  
9750 -8.0 17.6 225 19 10 1.1 0.6 | -7.6 18.3 205 18 9 8.5 4.7  
9500 -7.9 17.8 215 17 9 0.5 0.3 | -6.9 19.6 200 17 9 9.6 5.3  
9250 -7.8 18.0 200 15 8 0.8 0.4 | -6.2 20.8 195 17 9 9.7 5.3  
9000 -7.8 18.0 185 15 8 0.6 0.3 | -5.5 22.1 190 17 9 9.2 5.1  
8750 -7.6 18.3 170 15 8 4.5 2.5 | -4.0 24.8 185 17 9 11.1 6.1  
8500 -7.1 19.2 165 14 7 8.1 4.5 | -3.1 26.4 185 17 9 10.0 5.5  
8250 -6.5 20.3 160 14 7 6.5 3.6 | -2.4 27.7 185 17 9 11.5 6.3  
8000 -6.0 21.2 155 13 7 8.9 4.9 | -1.2 29.8 180 16 8 21.6 11.9  
7750 -3.6 25.5 150 10 5 20.4 11.2 | 1.1 34.0 180 14 7 40.4 22.2  
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  
 
03/04/2024 AT 1400 MST | 03/04/2024 AT 1700 MST  
|  
CAPE... +0.6 LI... +3.3 | CAPE... 0.0 LI... +2.0  
CINH... -0.1 K INDEX... -10.4 | CINH... 0.0 K INDEX... -3.8  
|  
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 -56.0 -68.8 260 71 37 1.6 0.9 | -56.0 -68.8 260 59 30 1.9 1.0  
45000 -53.4 -64.1 255 82 42 1.8 1.0 | -53.1 -63.6 255 75 38 2.0 1.1  
40000 -54.1 -65.4 250 74 38 -0.6 -0.3 | -54.2 -65.6 260 66 34 -1.0 -0.5  
38000 -54.5 -66.1 250 70 36 -1.2 -0.7 | -54.7 -66.5 260 62 32 -1.0 -0.5  
36000 -55.2 -67.4 245 66 34 -1.2 -0.7 | -55.3 -67.5 255 60 31 -1.0 -0.5  
34000 -56.0 -68.8 240 63 33 -1.5 -0.8 | -55.9 -68.6 255 57 29 1.4 0.8  
32000 -52.6 -62.7 245 62 32 6.5 3.6 | -52.3 -62.1 260 57 29 6.4 3.5  
30000 -48.6 -55.5 250 61 31 6.9 3.8 | -48.5 -55.3 265 58 30 7.0 3.9  
29000 -46.2 -51.2 250 62 32 8.2 4.5 | -46.2 -51.2 265 59 30 7.6 4.2  
28000 -43.7 -46.7 250 64 33 8.2 4.5 | -43.9 -47.0 265 59 30 7.6 4.2  
27000 -41.3 -42.3 250 65 34 8.2 4.5 | -41.6 -42.9 265 59 31 7.6 4.2  
26000 -38.1 -36.6 255 67 34 8.6 4.7 | -39.3 -38.7 265 60 31 8.3 4.6  
25000 -35.5 -31.9 255 67 35 8.6 4.7 | -36.8 -34.2 265 62 32 8.3 4.6  
24000 -32.9 -27.2 255 68 35 8.6 4.7 | -34.3 -29.7 265 64 33 8.3 4.6  
23000 -30.3 -22.5 255 65 34 8.6 4.7 | -31.7 -25.1 265 64 33 8.6 4.7  
22000 -27.7 -17.9 255 60 31 8.6 4.7 | -29.2 -20.6 265 63 32 8.6 4.7  
21000 -25.1 -13.2 255 56 29 8.6 4.7 | -26.6 -15.9 265 61 32 8.6 4.7  
20000 -22.9 -9.2 260 59 30 7.0 3.8 | -23.5 -10.3 265 62 32 8.2 4.5  
19500 -21.9 -7.4 265 62 32 7.0 3.8 | -22.3 -8.1 265 62 32 8.2 4.5  
19000 -20.8 -5.4 265 65 34 7.0 3.8 | -21.1 -6.0 265 63 32 8.2 4.5  
18500 -19.8 -3.6 265 68 35 7.0 3.8 | -19.8 -3.6 270 63 32 8.1 4.4  
18000 -18.8 -1.8 270 69 36 6.6 3.6 | -18.7 -1.7 270 63 32 7.2 3.9  
17500 -17.8 -0.0 270 69 35 6.6 3.6 | -17.6 0.3 270 62 32 7.3 4.0  
17000 -16.8 1.8 270 68 35 6.0 3.3 | -16.6 2.1 270 61 32 6.1 3.3  
16500 -16.0 3.2 270 65 33 5.5 3.0 | -15.7 3.7 270 59 31 5.8 3.2  
16000 -15.1 4.8 270 61 32 5.7 3.1 | -14.9 5.2 270 58 30 5.8 3.2  
15500 -14.2 6.4 265 57 29 7.0 3.8 | -14.0 6.8 265 53 27 5.9 3.2  
15000 -13.1 8.4 265 53 27 7.3 4.0 | -13.1 8.4 260 48 25 5.9 3.3  
14500 -12.4 9.7 260 50 26 3.5 1.9 | -12.2 10.0 255 45 23 6.5 3.5  
14000 -11.9 10.6 260 49 25 3.9 2.1 | -11.3 11.7 250 42 22 6.6 3.6  
13500 -11.2 11.8 260 46 24 7.7 4.2 | -10.3 13.5 250 40 20 9.3 5.1  
13000 -10.0 14.0 260 41 21 9.4 5.1 | -9.0 15.8 250 37 19 10.1 5.6  
12500 -9.4 15.1 255 35 18 3.4 1.9 | -8.1 17.4 250 33 17 4.9 2.7  
12000 -8.2 17.2 255 33 17 7.9 4.3 | -6.9 19.6 245 30 16 7.7 4.2  
11750 -7.6 18.3 255 31 16 7.9 4.3 | -6.3 20.7 245 29 15 9.4 5.2  
11500 -7.0 19.4 250 30 15 6.3 3.5 | -5.5 22.1 245 28 14 9.3 5.1  
11250 -6.6 20.1 250 28 14 5.9 3.2 | -4.9 23.2 240 27 14 7.4 4.1  
11000 -6.2 20.8 245 26 13 6.2 3.4 | -4.4 24.1 240 26 14 7.7 4.2  
10750 -5.7 21.7 245 24 13 5.9 3.2 | -3.8 25.2 240 25 13 6.7 3.7  
10500 -5.3 22.5 235 23 12 4.1 2.3 | -3.4 25.9 240 24 13 4.8 2.6  
10250 -5.0 23.0 230 21 11 6.1 3.3 | -3.0 26.6 235 23 12 6.2 3.4  
10000 -4.4 24.1 220 20 10 8.6 4.7 | -2.5 27.5 235 22 11 8.1 4.4  
9750 -3.8 25.2 215 19 10 8.0 4.4 | -1.9 28.6 230 21 11 6.6 3.6  
9500 -3.2 26.2 210 18 9 8.0 4.4 | -1.5 29.3 225 20 10 5.0 2.8  
9250 -2.5 27.5 200 18 9 8.5 4.7 | -1.1 30.0 220 19 10 6.0 3.3  
9000 -1.8 28.8 195 17 9 10.0 5.5 | -0.6 30.9 215 19 10 8.2 4.5  
8750 -1.1 30.0 190 17 9 10.5 5.8 | 0.1 32.2 205 18 9 8.4 4.6  
8500 -0.3 31.5 190 17 9 10.5 5.8 | 0.7 33.3 205 17 9 7.8 4.3  
8250 0.5 32.9 190 17 9 10.0 5.5 | 1.3 34.3 200 17 9 7.9 4.4  
8000 1.3 34.3 185 17 9 11.1 6.1 | 1.9 35.4 190 17 9 8.5 4.7  
7750 4.4 39.9 185 14 7 38.3 21.0 | 2.5 36.5 185 15 8 9.6 5.3  
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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