707  
UXUS97 KPUB 041223  
SRGPUB  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE PUEBLO, COLORADO  
0523 MST SATURDAY, JANUARY 4, 2025  
 
THIS FORECAST IS FOR THE AIR FORCE ACADEMY FOR SATURDAY, JANUARY 4, 2025:  
 
IF THE TRIGGER TEMPERATURE OF 56.1 F/13.4 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... POOR  
MAXIMUM RATE OF LIFT........................ 0 FT/MIN (0.0 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 7939 FT MSL (333 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 43.0 F/6.6 C  
TIME OF TRIGGER TEMPERATURE.................... NONE  
TIME OF OVERDEVELOPMENT........................ NONE  
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... OVERCAST OPAQUE HIGH  
SURFACE WINDS DURING SOARING WINDOW............ BETWEEN 20 MPH AND 30 MPH  
HEIGHT OF THE -3 THERMAL INDEX................. 7769 FT MSL (163 FT AGL)  
THERMAL SOARING OUTLOOK FOR SUNDAY 01/05....... POOR  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 07:18:25 / 16:50:32 MST  
TOTAL POSSIBLE SUNSHINE........... 9 HR 32 MIN 7 SEC (572 MIN 7 SEC)  
ALTITUDE OF SUN AT 12:04:28 MST... 28.38 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 01/04/2025 AT 0500 MST  
 
FREEZING LEVEL.................. 12254 FT MSL (4648 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 18964 FT MSL (11358 FT AGL)  
LIFTED CONDENSATION LEVEL....... 15177 FT MSL (7571 FT AGL)  
LIFTED INDEX.................... +9.8  
K INDEX......................... +0.6  
 
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 -61.2 -78.2 260 68 35 2.0 1.1 M M M M M  
45000 -58.1 -72.6 255 89 46 1.1 0.6 M M M M M  
40000 -59.7 -75.5 250 83 43 -1.1 -0.6 M M M M M  
38000 -58.6 -73.5 245 81 42 4.2 2.3 M M M M M  
36000 -56.1 -69.0 240 80 41 4.2 2.3 M M M M M  
34000 -53.0 -63.4 240 78 40 8.1 4.4 M M M M M  
32000 -48.1 -54.6 240 75 39 8.1 4.5 M M M M M  
30000 -43.1 -45.6 235 71 37 8.9 4.9 25.2 77.4 14.7 M M  
29000 -40.4 -40.7 235 67 35 9.0 4.9 24.8 76.7 14.6 M M  
28000 -37.7 -35.9 235 64 33 9.0 4.9 24.6 76.3 14.6 M M  
27000 -35.0 -31.0 235 60 31 8.0 4.4 24.4 76.0 14.6 M M  
26000 -33.0 -27.4 240 56 29 6.8 3.7 23.2 73.8 13.8 M M  
25000 -31.0 -23.8 240 53 27 6.8 3.7 22.1 71.8 13.0 M M  
24000 -29.0 -20.2 240 50 26 6.8 3.7 21.1 70.0 12.4 M M  
23000 -27.0 -16.6 240 48 25 6.6 3.6 19.9 67.9 11.5 M M  
22000 -24.6 -12.3 240 47 24 6.6 3.6 18.5 65.4 10.5 M M  
21000 -22.5 -8.5 240 46 24 7.7 4.2 17.6 63.6 9.7 M M  
20000 -20.3 -4.5 240 44 23 7.6 4.2 16.8 62.2 9.1 M M  
19500 -19.1 -2.4 240 43 22 7.6 4.2 16.4 61.5 8.9 M M  
19000 -18.0 -0.4 240 42 22 7.5 4.1 16.1 60.9 8.6 M M  
18500 -16.8 1.8 240 41 21 9.1 5.0 15.8 60.5 8.4 M M  
18000 -15.4 4.3 240 38 20 9.3 5.1 15.7 60.3 8.4 M M  
17500 -14.0 6.8 240 35 18 9.4 5.2 15.7 60.2 8.4 M M  
17000 -12.5 9.5 235 33 17 9.7 5.3 15.7 60.2 8.5 M M  
16500 -11.0 12.2 235 31 16 9.8 5.4 15.7 60.2 8.5 M M  
16000 -9.6 14.7 235 29 15 9.5 5.2 15.6 60.1 8.6 M M  
15500 -8.1 17.4 235 26 13 9.5 5.2 15.6 60.1 8.6 M M  
15000 -6.7 19.9 240 23 12 9.2 5.0 15.6 60.0 8.6 M M  
14500 -5.4 22.3 245 23 12 9.0 4.9 15.4 59.8 8.5 M M  
14000 -4.0 24.8 255 24 12 8.4 4.6 15.3 59.6 8.5 M M  
13500 -2.9 26.8 255 25 13 7.7 4.2 15.0 58.9 8.2 M M  
13000 -1.8 28.8 255 25 13 9.5 5.2 14.6 58.3 7.9 M M  
12500 -0.5 31.1 260 26 14 5.7 3.2 14.4 57.9 7.7 M M  
12000 0.4 32.7 260 28 14 6.6 3.6 13.9 57.0 7.2 M M  
11750 0.9 33.6 260 29 15 8.3 4.6 13.7 56.6 7.0 M M  
11500 1.5 34.7 260 30 15 7.4 4.0 13.6 56.4 6.9 M M  
11250 2.0 35.6 260 31 16 5.8 3.2 13.3 55.9 6.7 M M  
11000 2.4 36.3 260 32 16 6.4 3.5 13.0 55.4 6.4 M M  
10750 2.9 37.2 260 32 17 7.1 3.9 12.8 55.0 6.1 M M  
10500 3.4 38.1 260 31 16 7.5 4.1 12.6 54.7 6.0 M M  
10250 4.0 39.2 260 30 15 8.5 4.7 12.4 54.4 5.8 M M  
10000 4.7 40.5 260 29 15 8.7 4.8 12.4 54.3 5.8 M M  
9750 5.3 41.5 255 28 14 7.7 4.2 12.2 54.0 5.6 M M  
9500 5.8 42.4 255 27 14 6.5 3.6 12.1 53.7 5.5 M M  
9250 6.3 43.3 255 26 14 9.5 5.2 11.9 53.4 5.3 M M  
9000 7.1 44.8 255 25 13 6.0 3.3 11.9 53.3 5.3 M M  
8750 7.1 44.8 255 24 12 -2.0 -1.1 11.2 52.1 4.6 M M  
8500 6.8 44.2 250 23 12 -8.1 -4.4 10.1 50.2 3.6 M M  
8250 6.5 43.7 250 21 11 8.6 4.7 9.0 48.3 2.5 M M  
8000 7.3 45.1 250 18 9 -6.5 -3.6 9.1 48.5 2.6 M M  
7750 4.0 39.2 245 12 6 -81.3 -44.6 5.1 41.2 -1.4 159 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 * * * * * *  
 
01/04/2025 AT 0800 MST | 01/04/2025 AT 1100 MST  
|  
CAPE... 0.0 LI... +1.4 | CAPE... 0.0 LI... +1.7  
CINH... 0.0 K INDEX... +9.1 | CINH... 0.0 K INDEX... +5.2  
|  
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 -60.0 -76.0 260 58 30 1.5 0.8 | -58.8 -73.8 255 57 29 1.2 0.6  
45000 -57.8 -72.0 250 83 43 1.4 0.8 | -57.1 -70.8 245 74 38 1.4 0.8  
40000 -57.4 -71.3 245 83 43 0.2 0.1 | -58.0 -72.4 235 81 42 -0.7 -0.4  
38000 -56.5 -69.7 240 81 42 2.7 1.5 | -57.1 -70.8 235 83 43 4.3 2.3  
36000 -54.8 -66.6 240 78 40 2.7 1.5 | -54.5 -66.1 235 82 42 4.3 2.3  
34000 -52.8 -63.0 235 75 39 7.1 3.9 | -51.9 -61.4 235 81 42 5.5 3.0  
32000 -48.8 -55.8 230 71 36 6.7 3.7 | -48.6 -55.5 235 73 38 5.5 3.0  
30000 -44.7 -48.5 230 66 34 7.6 4.2 | -45.1 -49.2 230 66 34 7.8 4.3  
29000 -42.4 -44.3 230 61 31 7.6 4.2 | -42.9 -45.2 230 63 32 7.5 4.1  
28000 -40.1 -40.2 235 56 29 7.6 4.2 | -40.7 -41.3 230 60 31 7.5 4.1  
27000 -37.8 -36.0 235 52 27 7.8 4.3 | -38.4 -37.1 225 57 29 7.4 4.1  
26000 -35.3 -31.5 235 50 26 8.8 4.8 | -36.0 -32.8 230 56 29 8.1 4.5  
25000 -32.6 -26.7 235 49 25 8.8 4.8 | -33.6 -28.5 230 57 29 8.1 4.5  
24000 -30.0 -22.0 240 47 24 8.9 4.9 | -31.1 -24.0 235 58 30 8.2 4.5  
23000 -27.0 -16.6 240 45 23 7.9 4.3 | -28.8 -19.8 240 58 30 7.6 4.2  
22000 -24.7 -12.5 240 43 22 7.9 4.3 | -26.0 -14.8 240 56 29 7.6 4.2  
21000 -22.4 -8.3 235 42 21 6.9 3.8 | -23.7 -10.7 240 55 28 7.9 4.3  
20000 -20.4 -4.7 235 40 21 6.8 3.7 | -21.3 -6.3 235 53 27 8.0 4.4  
19500 -19.3 -2.7 235 39 20 6.8 3.7 | -20.1 -4.2 235 52 27 8.0 4.4  
19000 -18.3 -0.9 235 38 20 6.8 3.7 | -19.0 -2.2 235 51 26 8.0 4.4  
18500 -17.3 0.9 235 38 19 7.4 4.1 | -17.8 -0.0 235 50 26 7.6 4.2  
18000 -16.2 2.8 235 36 19 7.7 4.2 | -16.7 1.9 235 49 25 7.0 3.9  
17500 -15.0 5.0 235 35 18 7.8 4.3 | -15.6 3.9 230 48 24 6.9 3.8  
17000 -13.8 7.2 235 33 17 8.5 4.7 | -14.5 5.9 230 46 23 8.4 4.6  
16500 -12.5 9.5 230 32 16 8.4 4.6 | -13.2 8.2 230 43 22 8.3 4.6  
16000 -11.3 11.7 230 30 16 8.6 4.7 | -12.0 10.4 230 41 21 8.8 4.8  
15500 -10.0 14.0 225 29 15 8.7 4.8 | -10.6 12.9 230 40 21 9.0 4.9  
15000 -8.7 16.3 225 27 14 8.8 4.8 | -9.2 15.4 230 39 20 8.8 4.8  
14500 -7.3 18.9 220 25 13 8.8 4.8 | -8.0 17.6 230 36 18 8.3 4.5  
14000 -6.0 21.2 215 23 12 8.6 4.7 | -6.7 19.9 225 32 16 8.3 4.5  
13500 -4.8 23.4 220 22 11 8.2 4.5 | -5.6 21.9 220 27 14 6.7 3.7  
13000 -3.6 25.5 225 22 11 11.6 6.4 | -4.6 23.7 215 21 11 6.2 3.4  
12500 -2.2 28.0 230 22 12 5.5 3.0 | -3.3 26.1 220 20 10 8.5 4.6  
12000 -1.2 29.8 240 23 12 6.4 3.5 | -2.6 27.3 230 19 10 4.7 2.6  
11750 -0.7 30.7 240 24 12 9.0 5.0 | -2.3 27.9 235 19 10 6.8 3.7  
11500 0.1 32.2 245 24 12 9.1 5.0 | -1.6 29.1 240 19 10 7.8 4.3  
11250 0.7 33.3 245 24 13 7.2 4.0 | -1.2 29.8 245 20 10 6.2 3.4  
11000 1.2 34.2 245 25 13 7.7 4.2 | -0.7 30.7 250 21 11 6.4 3.5  
10750 1.8 35.2 245 25 13 7.8 4.3 | -0.2 31.6 255 22 12 7.1 3.9  
10500 2.4 36.3 245 25 13 8.1 4.4 | 0.4 32.7 255 23 12 8.1 4.4  
10250 3.0 37.4 245 24 12 8.3 4.6 | 1.0 33.8 255 23 12 8.4 4.6  
10000 3.6 38.5 245 24 12 8.5 4.7 | 1.6 34.9 255 24 12 8.8 4.9  
9750 4.2 39.6 245 24 12 7.4 4.0 | 2.3 36.1 255 24 12 8.5 4.6  
9500 4.7 40.5 245 24 12 6.2 3.4 | 2.9 37.2 255 23 12 7.9 4.3  
9250 5.2 41.4 245 23 12 7.7 4.2 | 3.5 38.3 255 22 12 8.7 4.8  
9000 5.8 42.4 245 23 12 6.6 3.6 | 4.2 39.6 250 21 11 10.7 5.9  
8750 6.1 43.0 245 21 11 -0.5 -0.3 | 4.8 40.6 250 20 10 4.7 2.6  
8500 5.7 42.3 240 20 10 -6.2 -3.4 | 4.9 40.8 245 18 9 -0.4 -0.2  
8250 5.4 41.7 240 19 10 1.6 0.9 | 4.9 40.8 240 16 8 1.0 0.5  
8000 5.6 42.1 235 17 9 -4.8 -2.6 | 5.1 41.2 235 13 7 6.8 3.7  
7750 3.9 39.0 235 12 6 -43.1 -23.6 | 6.0 42.8 225 10 5 17.9 9.8  
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  
 
01/04/2025 AT 1400 MST | 01/04/2025 AT 1700 MST  
|  
CAPE... 0.0 LI... +1.8 | CAPE... +25.8 LI... -1.7  
CINH... -0.1 K INDEX... +6.0 | CINH... -59.8 K INDEX... +12.0  
|  
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 -56.6 -69.9 265 48 25 0.9 0.5 | -55.9 -68.6 275 38 20 2.2 1.2  
45000 -55.3 -67.5 250 64 33 0.9 0.5 | -52.7 -62.9 265 49 25 2.2 1.2  
40000 -54.9 -66.8 240 67 35 0.2 0.1 | -51.7 -61.1 245 57 29 0.5 0.3  
38000 -54.3 -65.7 240 69 36 2.3 1.2 | -51.1 -60.0 240 60 31 2.0 1.1  
36000 -53.0 -63.4 235 72 37 2.2 1.2 | -49.9 -57.8 235 56 29 2.0 1.1  
34000 -51.6 -60.9 235 76 39 3.5 1.9 | -48.7 -55.7 230 52 27 1.9 1.0  
32000 -48.8 -55.8 230 76 39 4.7 2.6 | -46.5 -51.7 230 53 27 3.8 2.1  
30000 -45.9 -50.6 230 77 39 6.1 3.4 | -44.3 -47.7 230 55 28 3.7 2.0  
29000 -43.8 -46.8 230 75 39 7.1 3.9 | -42.9 -45.2 230 54 28 4.9 2.7  
28000 -41.7 -43.1 225 74 38 7.1 3.9 | -41.4 -42.5 230 52 27 4.9 2.7  
27000 -39.6 -39.3 225 72 37 7.1 3.9 | -39.9 -39.8 230 51 26 4.9 2.7  
26000 -37.1 -34.8 225 71 37 9.3 5.1 | -38.6 -37.5 230 49 25 2.9 1.6  
25000 -34.3 -29.7 220 70 36 9.4 5.1 | -37.7 -35.9 235 45 23 3.1 1.7  
24000 -31.5 -24.7 220 69 35 9.3 5.1 | -36.8 -34.2 240 41 21 3.1 1.7  
23000 -29.0 -20.2 220 67 35 7.3 4.0 | -35.1 -31.2 245 35 18 7.2 4.0  
22000 -26.2 -15.2 225 64 33 7.3 4.0 | -32.9 -27.2 245 30 16 7.2 3.9  
21000 -24.1 -11.4 230 61 31 7.1 3.9 | -30.8 -23.4 255 25 13 7.1 3.9  
20000 -22.2 -8.0 235 56 29 5.9 3.3 | -28.4 -19.1 260 23 12 8.7 4.8  
19500 -21.4 -6.5 235 54 28 5.9 3.3 | -27.1 -16.8 260 23 12 8.7 4.8  
19000 -20.5 -4.9 235 52 27 5.9 3.3 | -25.8 -14.4 265 23 12 8.7 4.8  
18500 -19.6 -3.3 235 49 25 5.9 3.2 | -24.5 -12.1 270 23 12 8.7 4.8  
18000 -18.7 -1.7 240 47 24 6.5 3.6 | -23.2 -9.8 270 23 12 8.3 4.5  
17500 -17.7 0.1 240 46 24 6.4 3.5 | -22.0 -7.6 275 24 13 8.2 4.5  
17000 -16.8 1.8 240 44 23 6.9 3.8 | -20.8 -5.4 275 26 13 8.3 4.6  
16500 -15.7 3.7 240 40 21 7.1 3.9 | -19.5 -3.1 275 26 14 8.6 4.7  
16000 -14.6 5.7 240 37 19 7.1 3.9 | -18.3 -0.9 270 27 14 8.6 4.7  
15500 -13.6 7.5 235 36 19 7.0 3.8 | -17.0 1.4 270 25 13 9.1 5.0  
15000 -12.5 9.5 235 36 18 6.9 3.8 | -15.7 3.7 265 23 12 9.1 5.0  
14500 -11.4 11.5 235 34 18 8.1 4.4 | -14.3 6.3 260 20 10 9.3 5.1  
14000 -10.2 13.6 235 31 16 7.8 4.3 | -13.0 8.6 260 17 9 9.3 5.1  
13500 -8.8 16.2 235 28 14 10.5 5.8 | -11.5 11.3 260 15 8 11.2 6.1  
13000 -7.3 18.9 235 25 13 12.1 6.6 | -9.8 14.4 265 17 9 13.5 7.4  
12500 -6.4 20.5 240 22 11 3.4 1.9 | -8.9 16.0 270 17 9 3.1 1.7  
12000 -5.2 22.6 240 22 11 7.6 4.1 | -7.5 18.5 270 18 9 8.3 4.6  
11750 -4.6 23.7 240 22 11 10.4 5.7 | -6.9 19.6 270 19 10 10.0 5.5  
11500 -3.8 25.2 245 21 11 10.4 5.7 | -6.1 21.0 270 19 10 11.4 6.3  
11250 -3.2 26.2 245 20 10 8.1 4.4 | -5.2 22.6 270 18 9 9.8 5.4  
11000 -2.6 27.3 245 19 10 8.7 4.8 | -4.6 23.7 270 18 9 8.5 4.7  
10750 -1.9 28.6 245 18 9 8.5 4.7 | -3.9 25.0 270 18 9 8.9 4.9  
10500 -1.3 29.7 245 18 9 8.8 4.8 | -3.3 26.1 275 18 9 8.3 4.6  
10250 -0.6 30.9 245 17 9 9.8 5.4 | -2.7 27.1 275 17 9 8.7 4.8  
10000 0.2 32.4 245 17 9 10.7 5.8 | -2.0 28.4 280 16 8 9.4 5.2  
9750 0.9 33.6 245 16 8 9.7 5.3 | -1.3 29.7 280 16 8 9.1 5.0  
9500 1.6 34.9 245 16 8 7.2 3.9 | -0.7 30.7 285 15 8 7.3 4.0  
9250 2.0 35.6 245 15 8 7.0 3.9 | -0.2 31.6 290 14 7 6.2 3.4  
9000 2.6 36.7 245 15 8 9.2 5.1 | 0.3 32.5 295 13 7 7.5 4.1  
8750 3.3 37.9 245 14 7 8.2 4.5 | 1.2 34.2 305 11 6 2.7 1.5  
8500 3.8 38.8 240 13 7 6.1 3.3 | 1.3 34.3 315 10 5 0.9 0.5  
8250 4.3 39.7 235 11 6 6.0 3.3 | 1.5 34.7 325 9 4 6.3 3.4  
8000 4.7 40.5 225 10 5 7.5 4.1 | 2.0 35.6 335 8 4 5.3 2.9  
7750 5.5 41.9 215 8 4 12.4 6.8 | 0.6 33.1 360 3 2 -61.7 -33.9  
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  
________________________________________________________________________________  
 
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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