448  
UXUS97 KPUB 281204  
SRGPUB  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE PUEBLO, COLORADO  
0604 MDT THURSDAY, MARCH 28, 2024  
 
THIS FORECAST IS FOR THE AIR FORCE ACADEMY FOR THURSDAY, MARCH 28, 2024:  
 
IF THE TRIGGER TEMPERATURE OF 47.1 F/8.4 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... GOOD  
MAXIMUM RATE OF LIFT........................ 758 FT/MIN (3.9 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 18120 FT MSL (10534 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 58.0 F/14.9 C  
TIME OF TRIGGER TEMPERATURE.................... 1115 MDT  
TIME OF OVERDEVELOPMENT........................ NONE  
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST THIN MIDDLE  
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS  
HEIGHT OF THE -3 THERMAL INDEX................. 14029 FT MSL (6443 FT AGL)  
THERMAL SOARING OUTLOOK FOR FRIDAY 03/29....... GOOD  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 06:48:44 / 19:19:25 MDT  
TOTAL POSSIBLE SUNSHINE........... 12 HR 30 MIN 41 SEC (750 MIN 41 SEC)  
ALTITUDE OF SUN AT 13:04:05 MDT... 54.41 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 03/28/2024 AT 0600 MDT  
 
FREEZING LEVEL.................. 8037 FT MSL (451 FT AGL)  
ADDITIONAL FREEZING LEVEL....... 9734 FT MSL (2148 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 18330 FT MSL (10744 FT AGL)  
LIFTED CONDENSATION LEVEL....... 18431 FT MSL (10845 FT AGL)  
LIFTED INDEX.................... +1.3  
K INDEX......................... +2.6  
 
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 -58.6 -73.5 270 58 30 -0.0 -0.0 M M M M M  
45000 -58.7 -73.7 275 69 36 -0.2 -0.1 M M M M M  
40000 -64.5 -84.1 275 73 38 -4.3 -2.4 M M M M M  
38000 -64.3 -83.7 275 75 38 7.6 4.2 M M M M M  
36000 -59.8 -75.6 275 76 39 7.5 4.1 M M M M M  
34000 -55.2 -67.4 280 77 39 8.5 4.7 M M M M M  
32000 -50.1 -58.2 280 73 38 8.4 4.6 M M M M M  
30000 -45.1 -49.2 285 69 36 7.6 4.2 23.6 74.5 7.0 M M  
29000 -42.8 -45.0 285 66 34 7.7 4.2 22.7 72.9 6.4 M M  
28000 -40.5 -40.9 285 63 32 7.7 4.2 21.9 71.5 5.9 M M  
27000 -38.2 -36.8 285 60 31 7.7 4.2 21.3 70.3 5.4 M M  
26000 -35.9 -32.6 285 56 29 7.8 4.3 20.5 68.8 4.8 M M  
25000 -33.5 -28.3 285 53 27 7.8 4.3 19.7 67.5 4.3 M M  
24000 -31.2 -24.2 285 49 25 7.9 4.3 19.1 66.4 3.8 M M  
23000 -28.8 -19.8 285 46 24 7.8 4.3 18.4 65.1 3.3 M M  
22000 -25.9 -14.6 280 43 22 7.8 4.3 17.5 63.6 2.6 M M  
21000 -23.6 -10.5 280 40 21 7.5 4.1 16.9 62.4 2.0 M M  
20000 -21.3 -6.3 285 38 19 7.5 4.1 16.0 60.9 1.3 M M  
19500 -20.2 -4.4 285 37 19 7.5 4.1 15.6 60.2 1.0 M M  
19000 -19.1 -2.4 285 35 18 7.5 4.1 15.3 59.5 0.7 M M  
18500 -18.0 -0.4 285 34 18 6.8 3.7 14.9 58.8 0.3 M M  
18000 -17.1 1.2 285 33 17 6.5 3.6 14.3 57.8 -0.2 942 4.8  
17500 -16.1 3.0 285 32 17 6.7 3.7 13.8 56.9 -0.7 899 4.6  
17000 -15.0 5.0 290 32 16 7.3 4.0 13.4 56.1 -1.1 852 4.3  
16500 -14.0 6.8 290 31 16 7.2 4.0 13.0 55.3 -1.5 805 4.1  
16000 -12.8 9.0 290 30 16 8.1 4.4 12.6 54.7 -1.8 756 3.8  
15500 -11.6 11.1 290 30 15 8.1 4.4 12.3 54.2 -2.1 705 3.6  
15000 -10.4 13.3 290 29 15 7.8 4.3 12.1 53.7 -2.4 654 3.3  
14500 -9.3 15.3 295 29 15 7.7 4.2 11.7 53.1 -2.7 605 3.1  
14000 -8.1 17.4 295 28 14 7.5 4.1 11.4 52.5 -3.0 555 2.8  
13500 -7.0 19.4 295 27 14 7.2 4.0 11.0 51.8 -3.4 508 2.6  
13000 -5.9 21.4 295 25 13 7.1 3.9 10.6 51.1 -3.8 461 2.3  
12500 -5.0 23.0 295 24 12 5.7 3.1 10.1 50.1 -4.4 418 2.1  
12000 -4.2 24.4 295 20 10 5.3 2.9 9.4 48.9 -5.0 378 1.9  
11750 -3.8 25.2 300 19 10 4.2 2.3 9.0 48.2 -5.4 360 1.8  
11500 -3.5 25.7 300 17 9 4.8 2.6 8.6 47.5 -5.9 344 1.7  
11250 -3.1 26.4 300 15 8 6.3 3.4 8.3 46.9 -6.2 324 1.6  
11000 -2.6 27.3 305 13 7 6.6 3.6 8.0 46.4 -6.5 302 1.5  
10750 -2.1 28.2 310 13 7 6.8 3.7 7.8 46.0 -6.7 280 1.4  
10500 -1.6 29.1 310 14 7 6.8 3.7 7.6 45.6 -7.0 257 1.3  
10250 -1.1 30.0 315 16 8 7.2 4.0 7.3 45.2 -7.2 235 1.2  
10000 -0.6 30.9 315 17 9 6.9 3.8 7.1 44.9 -7.4 211 1.1  
9750 -0.1 31.8 310 19 10 5.7 3.1 6.9 44.4 -7.7 190 1.0  
9500 0.3 32.5 310 19 10 5.9 3.2 6.6 43.8 -8.1 170 0.9  
9250 0.7 33.3 310 20 10 5.2 2.8 6.2 43.2 -8.4 150 0.8  
9000 1.0 33.8 310 21 11 2.7 1.5 5.8 42.5 -8.8 134 0.7  
8750 1.1 34.0 305 20 11 0.9 0.5 5.2 41.3 -9.5 123 0.6  
8500 1.3 34.3 300 20 11 3.5 1.9 4.6 40.2 -10.1 111 0.6  
8250 1.4 34.5 295 21 11 -4.9 -2.7 4.0 39.1 -10.8 100 0.5  
8000 0.3 32.5 295 21 11 -21.4 -11.8 2.2 35.9 -12.6 125 0.6  
7750 -1.5 29.3 290 14 7 -23.9 -13.1 -0.4 31.3 -15.2 173 0.9  
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 * * * * * *  
 
03/28/2024 AT 0900 MDT | 03/28/2024 AT 1200 MDT  
|  
CAPE... 0.0 LI... +2.8 | CAPE... 0.0 LI... +2.9  
CINH... 0.0 K INDEX... +0.4 | 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 -58.7 -73.7 265 57 30 -1.2 -0.7 | -58.9 -74.0 265 57 29 -1.6 -0.9  
45000 -60.5 -76.9 270 74 38 -1.3 -0.7 | -61.4 -78.5 265 76 39 -1.6 -0.9  
40000 -64.6 -84.3 270 78 40 -2.7 -1.5 | -63.6 -82.5 270 80 41 -1.4 -0.8  
38000 -63.7 -82.7 270 78 40 6.7 3.7 | -62.7 -80.9 270 79 41 5.3 2.9  
36000 -59.7 -75.5 275 78 40 6.7 3.7 | -59.6 -75.3 265 76 39 5.2 2.9  
34000 -55.6 -68.1 275 77 40 8.3 4.6 | -56.1 -69.0 265 73 38 9.1 5.0  
32000 -50.7 -59.3 275 72 37 8.1 4.5 | -50.9 -59.6 265 70 36 8.7 4.8  
30000 -45.9 -50.6 275 67 34 7.4 4.1 | -45.7 -50.3 265 66 34 8.2 4.5  
29000 -43.6 -46.5 275 65 33 7.5 4.1 | -43.3 -45.9 265 64 33 8.2 4.5  
28000 -41.4 -42.5 275 62 32 7.5 4.1 | -40.8 -41.4 265 62 32 8.2 4.5  
27000 -39.1 -38.4 275 60 31 7.6 4.2 | -38.3 -36.9 265 60 31 8.2 4.5  
26000 -36.7 -34.1 275 57 29 8.1 4.4 | -36.0 -32.8 265 58 30 7.8 4.3  
25000 -34.3 -29.7 270 53 27 8.1 4.5 | -33.7 -28.7 265 55 28 7.8 4.3  
24000 -31.9 -25.4 270 50 26 8.1 4.4 | -30.8 -23.4 265 52 27 8.1 4.4  
23000 -28.6 -19.5 270 48 25 8.9 4.9 | -28.3 -18.9 265 48 25 8.3 4.5  
22000 -25.9 -14.6 270 46 24 8.9 4.9 | -25.8 -14.4 265 43 22 8.3 4.5  
21000 -23.3 -9.9 270 44 23 6.9 3.8 | -23.4 -10.1 265 40 20 8.0 4.4  
20000 -21.3 -6.3 270 40 21 6.9 3.8 | -21.0 -5.8 265 38 20 8.0 4.4  
19500 -20.2 -4.4 270 39 20 6.9 3.8 | -19.8 -3.6 265 37 19 8.0 4.4  
19000 -19.2 -2.6 270 37 19 6.9 3.8 | -18.6 -1.5 265 36 19 8.0 4.4  
18500 -18.2 -0.8 270 35 18 7.5 4.1 | -17.4 0.7 270 36 18 7.9 4.3  
18000 -17.0 1.4 270 34 17 7.6 4.2 | -16.2 2.8 270 36 19 7.8 4.3  
17500 -15.9 3.4 275 33 17 7.6 4.2 | -15.1 4.8 270 37 19 7.7 4.2  
17000 -14.8 5.4 275 32 16 7.6 4.2 | -13.9 7.0 270 36 19 7.3 4.0  
16500 -13.6 7.5 275 30 16 7.6 4.1 | -12.8 9.0 265 35 18 7.3 4.0  
16000 -12.5 9.5 280 29 15 8.0 4.4 | -11.7 10.9 265 33 17 7.8 4.3  
15500 -11.3 11.7 280 28 14 8.0 4.4 | -10.5 13.1 265 32 16 7.8 4.3  
15000 -10.1 13.8 280 27 14 7.8 4.3 | -9.4 15.1 265 31 16 7.0 3.9  
14500 -8.9 16.0 280 25 13 7.6 4.2 | -8.4 16.9 265 29 15 6.6 3.6  
14000 -7.8 18.0 285 23 12 7.0 3.8 | -7.4 18.7 265 28 14 6.6 3.6  
13500 -6.9 19.6 285 21 11 6.3 3.4 | -6.4 20.5 265 26 13 6.7 3.7  
13000 -5.9 21.4 285 18 9 6.9 3.8 | -5.4 22.3 265 24 12 7.7 4.2  
12500 -4.9 23.2 285 17 9 6.5 3.5 | -4.4 24.1 265 23 12 4.8 2.7  
12000 -4.0 24.8 285 14 7 6.7 3.7 | -3.8 25.2 265 20 10 4.5 2.5  
11750 -3.4 25.9 285 13 7 8.0 4.4 | -3.4 25.9 265 19 10 4.7 2.6  
11500 -2.8 27.0 290 13 7 8.1 4.5 | -3.1 26.4 265 19 10 5.1 2.8  
11250 -2.2 28.0 290 13 7 8.1 4.5 | -2.7 27.1 265 17 9 5.5 3.0  
11000 -1.6 29.1 295 14 7 7.1 3.9 | -2.4 27.7 260 16 8 5.3 2.9  
10750 -1.2 29.8 295 14 7 5.3 2.9 | -2.0 28.4 260 15 7 4.6 2.5  
10500 -0.8 30.6 295 14 7 4.8 2.6 | -1.7 28.9 255 13 7 3.9 2.1  
10250 -0.5 31.1 300 14 7 5.4 2.9 | -1.4 29.5 245 11 6 6.9 3.8  
10000 -0.1 31.8 300 13 7 5.4 3.0 | -0.8 30.6 235 10 5 9.0 5.0  
9750 0.3 32.5 300 12 6 4.8 2.6 | -0.2 31.6 225 9 5 8.0 4.4  
9500 0.6 33.1 300 11 6 5.1 2.8 | 0.4 32.7 210 9 5 7.6 4.2  
9250 1.0 33.8 300 9 5 4.1 2.2 | 1.0 33.8 200 9 5 9.1 5.0  
9000 1.2 34.2 300 8 4 4.4 2.4 | 1.8 35.2 190 9 5 10.7 5.8  
8750 1.6 34.9 300 8 4 5.0 2.7 | 2.5 36.5 185 9 5 10.1 5.5  
8500 2.0 35.6 295 7 4 6.4 3.5 | 3.3 37.9 185 9 5 10.0 5.5  
8250 2.4 36.3 295 7 4 0.1 0.1 | 4.0 39.2 180 9 5 10.2 5.6  
8000 2.0 35.6 290 8 4 -4.0 -2.2 | 4.9 40.8 180 9 5 14.1 7.7  
7750 2.1 35.8 280 6 3 8.2 4.5 | 6.1 43.0 180 9 5 19.7 10.8  
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  
 
03/28/2024 AT 1500 MDT | 03/28/2024 AT 1800 MDT  
|  
CAPE... +11.0 LI... +1.2 | CAPE... +63.0 LI... -0.4  
CINH... -16.0 K INDEX... +12.4 | CINH... -18.6 K INDEX... +13.6  
|  
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 -59.3 -74.7 265 57 29 -1.0 -0.6 | -61.0 -77.8 260 60 31 -0.6 -0.4  
45000 -60.8 -77.4 270 76 39 -1.0 -0.6 | -62.0 -79.6 265 73 38 -0.7 -0.4  
40000 -62.4 -80.3 270 89 46 -1.0 -0.6 | -62.2 -80.0 270 89 46 -0.1 -0.0  
38000 -61.5 -78.7 270 90 46 4.7 2.6 | -60.6 -77.1 270 94 48 5.7 3.1  
36000 -58.7 -73.7 265 84 43 4.6 2.5 | -57.2 -71.0 270 95 49 5.7 3.1  
34000 -55.6 -68.1 265 79 40 8.9 4.9 | -53.7 -64.7 270 95 49 6.9 3.8  
32000 -50.5 -58.9 260 73 38 8.4 4.6 | -49.6 -57.3 265 88 45 6.8 3.7  
30000 -45.4 -49.7 260 68 35 8.6 4.7 | -45.3 -49.5 265 79 41 9.0 4.9  
29000 -42.9 -45.2 260 67 35 8.6 4.7 | -42.7 -44.9 265 71 37 8.9 4.9  
28000 -40.3 -40.5 260 67 34 8.6 4.7 | -40.0 -40.0 260 64 33 8.9 4.9  
27000 -37.7 -35.9 260 66 34 8.5 4.6 | -37.4 -35.3 260 56 29 8.8 4.8  
26000 -35.3 -31.5 260 65 33 7.7 4.2 | -35.0 -31.0 260 57 30 7.9 4.3  
25000 -33.0 -27.4 260 64 33 7.7 4.2 | -32.6 -26.7 265 60 31 7.9 4.3  
24000 -30.7 -23.3 260 63 32 7.7 4.2 | -30.3 -22.5 265 64 33 7.9 4.4  
23000 -27.8 -18.0 260 57 29 7.9 4.4 | -27.5 -17.5 265 57 30 7.2 4.0  
22000 -25.4 -13.7 255 52 27 8.0 4.4 | -25.3 -13.5 265 50 26 7.2 4.0  
21000 -23.0 -9.4 255 47 24 8.5 4.7 | -23.2 -9.8 260 45 23 7.4 4.1  
20000 -20.4 -4.7 255 45 23 8.6 4.7 | -20.9 -5.6 265 48 25 7.5 4.1  
19500 -19.2 -2.6 260 44 22 8.6 4.7 | -19.8 -3.6 265 50 26 7.5 4.1  
19000 -17.9 -0.2 260 42 22 8.6 4.7 | -18.7 -1.7 265 51 26 7.5 4.1  
18500 -16.6 2.1 265 42 22 8.0 4.4 | -17.6 0.3 265 53 27 7.4 4.0  
18000 -15.5 4.1 265 44 23 7.8 4.3 | -16.5 2.3 265 53 27 7.3 4.0  
17500 -14.3 6.3 265 46 24 7.6 4.1 | -15.5 4.1 265 52 27 7.4 4.0  
17000 -13.3 8.1 265 47 24 6.0 3.3 | -14.3 6.3 265 51 26 7.7 4.2  
16500 -12.4 9.7 265 48 25 6.1 3.3 | -13.2 8.2 265 48 25 7.8 4.3  
16000 -11.4 11.5 265 47 24 6.7 3.7 | -12.1 10.2 265 45 23 6.6 3.6  
15500 -10.4 13.3 265 45 23 6.7 3.7 | -11.1 12.0 260 41 21 6.5 3.6  
15000 -9.5 14.9 265 43 22 6.2 3.4 | -10.1 13.8 255 38 19 7.0 3.9  
14500 -8.6 16.5 265 43 22 5.9 3.2 | -9.0 15.8 260 39 20 7.5 4.1  
14000 -7.7 18.1 265 43 22 6.1 3.4 | -7.9 17.8 260 41 21 7.9 4.3  
13500 -6.8 19.8 260 38 19 6.9 3.8 | -6.7 19.9 260 37 19 8.9 4.9  
13000 -5.9 21.4 255 32 17 9.7 5.3 | -5.5 22.1 255 33 17 11.8 6.5  
12500 -4.4 24.1 250 29 15 7.8 4.3 | -3.9 25.0 255 31 16 7.8 4.3  
12000 -3.3 26.1 245 24 13 8.1 4.4 | -2.6 27.3 250 27 14 8.4 4.6  
11750 -2.6 27.3 245 23 12 9.0 5.0 | -2.0 28.4 250 26 13 9.5 5.2  
11500 -1.9 28.6 240 22 11 9.5 5.2 | -1.3 29.7 250 25 13 9.9 5.4  
11250 -1.2 29.8 240 21 11 9.5 5.2 | -0.6 30.9 250 25 13 9.5 5.2  
11000 -0.5 31.1 235 20 10 9.3 5.1 | 0.1 32.2 245 24 12 9.5 5.2  
10750 0.1 32.2 235 20 10 8.2 4.5 | 0.8 33.4 245 23 12 8.6 4.7  
10500 0.7 33.3 230 19 10 7.7 4.2 | 1.4 34.5 245 22 11 8.1 4.5  
10250 1.4 34.5 225 18 9 10.3 5.6 | 2.1 35.8 245 22 11 9.9 5.5  
10000 2.2 36.0 225 18 9 11.4 6.3 | 2.9 37.2 240 21 11 10.6 5.8  
9750 3.0 37.4 225 17 9 9.8 5.4 | 3.6 38.5 240 20 10 9.1 5.0  
9500 3.7 38.7 220 16 8 9.5 5.2 | 4.2 39.6 240 20 10 8.2 4.5  
9250 4.4 39.9 220 16 8 9.4 5.2 | 4.9 40.8 235 19 10 9.7 5.3  
9000 5.1 41.2 215 15 8 9.7 5.3 | 5.7 42.3 235 18 9 10.9 6.0  
8750 5.8 42.4 215 15 8 10.3 5.7 | 6.4 43.5 230 17 9 9.3 5.1  
8500 6.6 43.9 215 15 7 10.9 6.0 | 7.1 44.8 230 16 8 8.5 4.7  
8250 7.4 45.3 210 14 7 9.2 5.1 | 7.7 45.9 230 16 8 9.5 5.2  
8000 8.1 46.6 205 13 7 11.0 6.0 | 8.3 46.9 225 15 8 4.2 2.3  
7750 9.1 48.4 205 12 6 18.7 10.3 | 8.1 46.6 220 11 6 -7.3 -4.0  
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 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.  
 
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