188  
UXUS97 KBOU 260016  
SRGBOU  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO  
1816 MDT SUNDAY, JUNE 25, 2017  
 
THIS FORECAST IS FOR MONDAY, JUNE 26, 2017:  
 
IF THE TRIGGER TEMPERATURE OF 75.4 F/24.1 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... EXCELLENT  
MAXIMUM RATE OF LIFT........................ 995 FT/MIN (5.1 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 16560 FT MSL (11253 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 85.0 F/29.9 C  
TIME OF TRIGGER TEMPERATURE.................... 1045 MDT  
TIME OF OVERDEVELOPMENT........................ 1800 MDT  
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE  
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS  
HEIGHT OF THE -3 THERMAL INDEX................. 11813 FT MSL (6506 FT AGL)  
THERMAL SOARING OUTLOOK FOR TUESDAY 06/27...... EXCELLENT  
 
WAVE SOARING INDEX............................. POOR  
WAVE SOARING INDEX TREND (TO 1800 MDT)......... NO CHANGE  
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE  
WEAK PVA/NVA (THROUGH 1800 MDT)................ NEITHER  
POTENTIAL HEIGHT OF WAVE....................... 32071 FT MSL (26764 FT AGL)  
WAVE SOARING OUTLOOK FOR TUESDAY 06/27......... POOR  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 05:33:19 / 20:31:30 MDT  
TOTAL POSSIBLE SUNSHINE........... 14 HR 58 MIN 11 SEC (898 MIN 11 SEC)  
ALTITUDE OF SUN AT 13:02:29 MDT... 73.53 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 06/26/2017 AT 0600 MDT  
 
FREEZING LEVEL.................. 14422 FT MSL (9115 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 12293 FT MSL (6986 FT AGL)  
LIFTED CONDENSATION LEVEL....... 13578 FT MSL (8271 FT AGL)  
LIFTED INDEX.................... -6.9  
K INDEX......................... +18.5  
 
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 -62.8 -81.0 315 39 20 1.2 0.7 M M M M M  
45000 -60.0 -76.0 305 42 22 3.8 2.1 M M M M M  
40000 -53.8 -64.8 295 30 16 6.1 3.3 M M M M M  
38000 -50.2 -58.4 300 30 15 6.0 3.3 M M M M M  
36000 -46.6 -51.9 300 30 15 6.0 3.3 M M M M M  
34000 -42.4 -44.3 305 32 16 7.4 4.0 M M M M M  
32000 -38.0 -36.4 310 34 17 7.3 4.0 M M M M M  
30000 -33.9 -29.0 315 34 18 6.6 3.6 42.3 108.1 9.8 M M  
29000 -31.5 -24.7 315 34 18 6.6 3.6 40.8 105.4 8.7 M M  
28000 -29.5 -21.1 320 34 18 7.2 3.9 39.7 103.5 8.0 M M  
27000 -27.3 -17.1 320 34 18 7.5 4.1 38.7 101.7 7.3 M M  
26000 -25.1 -13.2 325 34 18 7.5 4.1 37.9 100.2 6.7 M M  
25000 -22.8 -9.0 325 34 18 7.5 4.1 37.1 98.8 6.2 M M  
24000 -20.5 -4.9 325 33 17 7.9 4.3 36.3 97.4 5.6 M M  
23000 -18.1 -0.6 325 33 17 7.9 4.3 35.6 96.2 5.1 M M  
22000 -15.8 3.6 325 32 16 7.9 4.3 35.1 95.1 4.7 M M  
21000 -13.4 7.9 325 30 16 7.9 4.3 34.3 93.8 4.1 M M  
20000 -11.1 12.0 325 29 15 7.9 4.3 33.7 92.6 3.6 M M  
19500 -9.9 14.2 330 28 14 8.1 4.4 33.4 92.1 3.3 M M  
19000 -8.8 16.2 330 27 14 6.1 3.3 33.0 91.3 3.0 M M  
18500 -7.9 17.8 330 26 14 6.2 3.4 32.4 90.2 2.4 M M  
18000 -7.0 19.4 330 26 13 6.2 3.4 31.8 89.2 1.9 M M  
17500 -6.2 20.8 330 24 12 6.0 3.3 31.1 88.0 1.3 M M  
17000 -5.3 22.5 330 22 11 6.1 3.3 30.5 86.9 0.7 M M  
16500 -4.5 23.9 325 21 11 5.6 3.1 29.8 85.7 0.1 M M  
16000 -3.7 25.3 325 19 10 5.7 3.1 29.1 84.4 -0.6 959 4.9  
15500 -2.8 27.0 325 18 9 7.2 3.9 28.5 83.4 -1.2 919 4.7  
15000 -1.2 29.8 330 16 8 7.7 4.2 28.0 82.5 -1.7 846 4.3  
14500 0.1 32.2 330 14 7 9.3 5.1 27.8 82.1 -2.0 795 4.0  
14000 1.5 34.7 335 13 7 9.4 5.1 27.7 81.9 -2.0 738 3.7  
13500 2.9 37.2 335 11 6 8.2 4.5 27.6 81.7 -2.1 682 3.5  
13000 4.0 39.2 340 10 5 7.9 4.3 27.3 81.2 -2.5 633 3.2  
12500 5.1 41.2 340 9 5 8.3 4.6 27.0 80.6 -2.8 584 3.0  
12000 6.4 43.5 350 8 4 8.6 4.7 26.8 80.3 -3.0 530 2.7  
11500 7.7 45.9 360 7 4 8.2 4.5 26.7 80.0 -3.1 477 2.4  
11000 8.9 48.0 355 5 2 7.7 4.2 26.4 79.5 -3.5 428 2.2  
10500 10.0 50.0 340 3 1 4.2 2.3 26.1 78.9 -3.9 380 1.9  
10250 10.1 50.2 335 2 1 4.0 2.2 25.5 77.8 -4.5 369 1.9  
10000 10.6 51.1 325 2 1 10.1 5.5 25.3 77.6 -4.7 346 1.8  
9750 11.3 52.3 315 3 1 10.6 5.8 25.4 77.7 -4.8 320 1.6  
9500 11.9 53.4 300 3 1 8.1 4.4 25.4 77.7 -4.9 293 1.5  
9250 12.3 54.1 290 3 2 5.3 2.9 25.1 77.2 -5.2 273 1.4  
9000 12.8 55.0 275 4 2 9.2 5.0 24.9 76.8 -5.5 253 1.3  
8750 13.5 56.3 265 5 3 11.3 6.2 25.0 76.9 -5.5 223 1.1  
8500 14.1 57.4 255 7 4 6.9 3.8 24.9 76.9 -5.7 198 1.0  
8250 14.4 57.9 250 8 4 5.0 2.7 24.6 76.2 -6.1 181 0.9  
8000 14.7 58.5 245 9 5 4.8 2.7 24.2 75.6 -6.6 165 0.8  
7750 14.9 58.8 245 10 5 3.6 2.0 23.8 74.8 -7.1 151 0.8  
7500 15.1 59.2 245 10 5 4.0 2.2 23.3 74.0 -7.6 138 0.7  
7250 15.3 59.5 240 9 5 4.2 2.3 22.9 73.2 -8.1 123 0.6  
7000 15.6 60.1 240 9 5 4.5 2.5 22.5 72.5 -8.6 109 0.6  
6750 15.8 60.4 240 8 4 3.1 1.7 22.1 71.7 -9.1 94 0.5  
6500 15.9 60.6 230 8 4 1.2 0.7 21.5 70.6 -9.8 84 0.4  
6250 16.0 60.8 220 7 4 2.8 1.5 20.9 69.6 -10.5 73 0.4  
6000 16.1 61.0 215 7 3 -1.6 -0.9 20.3 68.5 -11.1 63 0.3  
5750 15.7 60.3 205 5 2 -7.4 -4.0 19.1 66.5 -12.3 69 0.3  
5500 15.2 59.4 200 2 1 -4.4 -2.4 17.9 64.3 -13.5 76 0.4  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
06/26/2017 AT 0900 MDT | 06/26/2017 AT 1200 MDT  
|  
K INDEX... +14.1 LI... -3.2 | K INDEX... +7.7 LI... -4.5  
CAPE... +881.6 CIN... -109.7 | CAPE... +1528.3 CIN... -10.6  
|  
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 -62.5 -80.5 325 36 19 1.8 1.0 | -62.6 -80.7 325 36 19 2.2 1.2  
45000 -59.3 -74.7 315 43 22 3.3 1.8 | -58.9 -74.0 320 43 22 3.3 1.8  
40000 -53.8 -64.8 310 35 18 5.9 3.2 | -53.5 -64.3 310 42 22 5.1 2.8  
38000 -50.4 -58.7 310 34 17 5.7 3.2 | -50.5 -58.9 310 39 20 5.0 2.8  
36000 -47.0 -52.6 310 32 16 5.8 3.2 | -47.5 -53.5 310 37 19 5.0 2.8  
34000 -42.8 -45.0 315 33 17 7.2 4.0 | -43.6 -46.5 315 34 18 7.0 3.8  
32000 -38.5 -37.3 320 35 18 7.2 4.0 | -39.4 -38.9 325 33 17 7.0 3.8  
30000 -33.9 -29.0 330 34 18 6.7 3.7 | -34.4 -29.9 335 31 16 7.5 4.1  
29000 -31.9 -25.4 330 34 17 6.7 3.7 | -32.2 -26.0 340 30 15 7.5 4.1  
28000 -29.9 -21.8 335 33 17 7.3 4.0 | -30.0 -22.0 340 29 15 7.9 4.3  
27000 -27.6 -17.7 335 33 17 7.7 4.2 | -27.5 -17.5 340 28 14 8.1 4.5  
26000 -25.3 -13.5 330 33 17 7.7 4.2 | -25.1 -13.2 340 27 14 8.1 4.5  
25000 -23.0 -9.4 330 34 17 7.7 4.2 | -22.7 -8.9 335 27 14 8.2 4.5  
24000 -20.6 -5.1 330 33 17 8.0 4.4 | -20.2 -4.4 335 26 14 8.4 4.6  
23000 -18.3 -0.9 330 32 16 8.0 4.4 | -17.7 0.1 335 26 14 8.4 4.6  
22000 -15.9 3.4 330 31 16 7.9 4.3 | -15.2 4.6 330 26 13 8.0 4.4  
21000 -13.6 7.5 330 29 15 7.6 4.2 | -13.0 8.6 330 25 13 7.2 3.9  
20000 -11.3 11.7 330 28 14 7.6 4.2 | -10.9 12.4 325 25 13 7.2 3.9  
19500 -10.2 13.6 330 27 14 7.6 4.2 | -9.8 14.4 325 24 12 7.2 3.9  
19000 -9.0 15.8 330 26 13 7.4 4.1 | -8.7 16.3 325 24 12 7.5 4.1  
18500 -7.9 17.8 330 25 13 7.4 4.1 | -7.6 18.3 325 23 12 7.5 4.1  
18000 -6.8 19.8 330 23 12 7.1 3.9 | -6.5 20.3 325 22 11 7.5 4.1  
17500 -5.8 21.6 330 22 11 6.7 3.7 | -5.4 22.3 320 21 11 7.5 4.1  
17000 -4.9 23.2 325 21 11 6.8 3.7 | -4.3 24.3 320 20 10 7.6 4.1  
16500 -4.0 24.8 325 20 10 6.0 3.3 | -3.3 26.1 320 19 10 6.5 3.6  
16000 -3.1 26.4 320 18 10 6.2 3.4 | -2.3 27.9 320 18 9 6.6 3.6  
15500 -1.8 28.8 315 16 8 6.8 3.7 | -0.8 30.6 315 16 8 6.8 3.7  
15000 -0.8 30.6 315 14 7 6.7 3.7 | 0.1 32.2 310 15 8 7.0 3.9  
14500 0.2 32.4 315 13 6 7.9 4.3 | 1.0 33.8 305 14 7 6.6 3.6  
14000 1.3 34.3 320 11 6 7.8 4.3 | 1.9 35.4 300 11 6 6.7 3.7  
13500 2.5 36.5 325 9 5 8.2 4.5 | 2.9 37.2 295 9 5 7.2 4.0  
13000 3.7 38.7 330 8 4 8.3 4.5 | 3.9 39.0 295 7 3 7.3 4.0  
12500 4.9 40.8 340 7 4 8.7 4.8 | 5.0 41.0 295 4 2 8.2 4.5  
12000 6.3 43.3 345 6 3 8.9 4.9 | 6.4 43.5 295 3 2 8.6 4.7  
11500 7.7 45.9 350 5 2 8.7 4.8 | 7.7 45.9 290 2 1 8.7 4.8  
11000 8.9 48.0 345 3 2 8.3 4.6 | 9.0 48.2 260 2 1 8.5 4.7  
10500 10.2 50.4 335 2 1 4.8 2.6 | 10.3 50.5 235 2 1 4.0 2.2  
10250 10.4 50.7 325 1 1 5.0 2.7 | 10.5 50.9 230 2 1 5.4 3.0  
10000 11.1 52.0 295 1 1 11.2 6.1 | 11.3 52.3 225 2 1 12.8 7.0  
9750 11.8 53.2 255 1 1 11.7 6.4 | 12.2 54.0 225 2 1 12.1 6.6  
9500 12.6 54.7 235 2 1 7.8 4.3 | 12.9 55.2 220 2 1 8.1 4.4  
9250 12.9 55.2 240 2 1 4.0 2.2 | 13.3 55.9 215 2 1 4.6 2.6  
9000 13.3 55.9 245 2 1 7.9 4.4 | 13.7 56.7 205 1 1 8.3 4.5  
8750 13.9 57.0 255 1 1 10.0 5.5 | 14.3 57.7 090 1 0 9.6 5.2  
8500 14.5 58.1 275 1 1 7.7 4.2 | 14.8 58.6 060 2 1 7.5 4.1  
8250 14.9 58.8 290 2 1 6.7 3.7 | 15.1 59.2 050 3 2 6.7 3.7  
8000 15.4 59.7 300 2 1 7.6 4.2 | 15.5 59.9 050 5 2 7.8 4.3  
7750 15.8 60.4 305 3 1 4.8 2.6 | 15.9 60.6 045 5 3 9.1 5.0  
7500 15.8 60.4 315 3 2 -0.6 -0.3 | 16.5 61.7 045 6 3 9.9 5.4  
7250 15.6 60.1 330 4 2 -1.2 -0.7 | 17.2 63.0 045 6 3 9.8 5.4  
7000 15.4 59.7 345 4 2 -2.5 -1.4 | 17.9 64.2 045 6 3 10.4 5.7  
6750 15.0 59.0 355 5 3 1.5 0.8 | 18.7 65.7 045 6 3 10.7 5.9  
6500 15.4 59.7 355 5 3 6.3 3.5 | 19.5 67.1 045 6 3 10.3 5.7  
6250 15.8 60.4 360 5 3 4.8 2.6 | 20.2 68.4 040 6 3 10.1 5.5  
6000 16.1 61.0 005 6 3 6.2 3.4 | 21.0 69.8 040 6 3 11.4 6.2  
5750 16.8 62.2 005 6 3 14.0 7.7 | 22.1 71.8 040 6 3 19.2 10.5  
5500 18.2 64.8 005 6 3 24.0 13.1 | 23.9 75.0 040 6 3 28.0 15.4  
 
06/26/2017 AT 1500 MDT | 06/26/2017 AT 1800 MDT  
|  
K INDEX... +26.1 LI... -2.3 | K INDEX... +33.9 LI... -2.6  
CAPE... +671.9 CIN... -38.4 | CAPE... +797.1 CIN... -10.5  
|  
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 -63.4 -82.1 325 36 18 2.9 1.6 | -63.9 -83.0 320 36 19 2.9 1.6  
45000 -58.1 -72.6 325 45 23 4.6 2.5 | -58.2 -72.8 315 44 23 5.4 2.9  
40000 -51.4 -60.5 325 53 27 3.4 1.9 | -50.3 -58.5 315 48 25 4.1 2.3  
38000 -49.3 -56.7 320 45 23 3.4 1.9 | -47.9 -54.2 310 45 23 4.1 2.3  
36000 -47.3 -53.1 315 38 20 3.5 1.9 | -45.4 -49.7 310 41 21 4.1 2.3  
34000 -43.7 -46.7 315 33 17 6.7 3.7 | -42.2 -44.0 310 38 19 5.7 3.1  
32000 -39.7 -39.5 315 29 15 6.7 3.7 | -38.8 -37.8 305 34 18 5.7 3.1  
30000 -34.8 -30.6 320 26 13 7.6 4.2 | -34.2 -29.6 305 32 16 7.1 3.9  
29000 -32.5 -26.5 320 25 13 7.6 4.2 | -32.1 -25.8 305 31 16 7.1 3.9  
28000 -30.2 -22.4 320 24 12 8.1 4.5 | -29.9 -21.8 305 30 15 7.7 4.2  
27000 -27.7 -17.9 315 25 13 8.3 4.6 | -27.5 -17.5 305 29 15 8.0 4.4  
26000 -25.3 -13.5 315 25 13 8.3 4.6 | -25.1 -13.2 305 29 15 8.0 4.4  
25000 -22.8 -9.0 315 26 13 8.4 4.6 | -22.7 -8.9 305 28 14 8.0 4.4  
24000 -20.2 -4.4 315 26 14 8.4 4.6 | -20.3 -4.5 310 28 14 8.4 4.6  
23000 -17.7 0.1 315 26 14 8.4 4.6 | -17.8 -0.0 310 28 15 8.4 4.6  
22000 -15.2 4.6 315 26 14 8.0 4.4 | -15.3 4.5 310 29 15 8.3 4.5  
21000 -13.0 8.6 315 26 13 7.1 3.9 | -12.9 8.8 310 28 14 8.0 4.4  
20000 -10.9 12.4 315 25 13 7.1 3.9 | -10.5 13.1 310 27 14 8.1 4.4  
19500 -9.9 14.2 315 25 13 7.0 3.9 | -9.3 15.3 310 26 13 8.1 4.5  
19000 -8.7 16.3 310 25 13 8.4 4.6 | -8.1 17.4 305 26 13 8.2 4.5  
18500 -7.5 18.5 310 24 12 8.3 4.5 | -6.9 19.6 305 26 13 8.2 4.5  
18000 -6.3 20.7 310 23 12 8.5 4.6 | -5.7 21.7 305 26 13 8.1 4.5  
17500 -5.0 23.0 305 22 11 8.7 4.8 | -4.6 23.7 300 25 13 8.1 4.4  
17000 -3.8 25.2 300 21 11 8.7 4.8 | -3.4 25.9 300 24 12 8.4 4.6  
16500 -2.6 27.3 300 20 11 8.4 4.6 | -2.4 27.7 295 21 11 7.0 3.9  
16000 -0.8 30.6 295 19 10 8.4 4.6 | -1.0 30.2 285 16 8 7.5 4.1  
15500 0.3 32.5 295 18 9 7.5 4.1 | -0.1 31.8 275 12 6 5.7 3.1  
15000 1.3 34.3 290 16 8 7.8 4.3 | 0.6 33.1 260 8 4 5.8 3.2  
14500 2.3 36.1 290 14 7 6.4 3.5 | 1.5 34.7 225 5 3 6.3 3.5  
14000 3.2 37.8 280 11 5 6.5 3.6 | 2.4 36.3 185 4 2 6.3 3.5  
13500 4.1 39.4 265 8 4 5.9 3.2 | 3.4 38.1 155 5 3 8.4 4.6  
13000 4.9 40.8 245 4 2 5.7 3.1 | 4.7 40.5 140 6 3 9.2 5.0  
12500 5.8 42.4 180 3 2 7.2 4.0 | 6.1 43.0 125 6 3 9.4 5.2  
12000 7.0 44.6 140 3 2 8.2 4.5 | 7.5 45.5 125 6 3 9.6 5.3  
11500 8.1 46.6 110 4 2 8.7 4.8 | 8.9 48.0 120 6 3 9.7 5.3  
11000 9.5 49.1 105 4 2 8.9 4.9 | 10.4 50.7 120 6 3 9.3 5.1  
10500 10.8 51.4 105 4 2 4.7 2.6 | 11.8 53.2 120 6 3 4.1 2.3  
10250 11.0 51.8 105 4 2 6.8 3.7 | 11.9 53.4 115 6 3 6.0 3.3  
10000 11.9 53.4 100 4 2 13.8 7.6 | 12.9 55.2 115 6 3 14.2 7.8  
9750 12.8 55.0 100 4 2 12.6 6.9 | 13.8 56.8 115 6 3 12.9 7.1  
9500 13.7 56.7 100 4 2 9.6 5.2 | 14.7 58.5 115 6 3 9.8 5.4  
9250 14.3 57.7 095 4 2 7.0 3.9 | 15.3 59.5 115 6 3 6.9 3.8  
9000 15.0 59.0 095 4 2 11.3 6.2 | 15.9 60.6 110 6 3 10.7 5.9  
8750 15.9 60.6 095 4 2 12.6 6.9 | 16.8 62.2 110 6 3 12.1 6.6  
8500 16.7 62.1 095 4 2 10.2 5.6 | 17.7 63.9 110 5 3 10.6 5.8  
8250 17.4 63.3 090 4 2 8.5 4.7 | 18.4 65.1 110 5 3 9.5 5.2  
8000 18.1 64.6 090 4 2 9.9 5.4 | 19.1 66.4 105 5 3 10.0 5.5  
7750 18.9 66.0 090 4 2 10.9 6.0 | 19.9 67.8 105 5 3 10.3 5.6  
7500 19.7 67.5 090 4 2 10.2 5.6 | 20.6 69.1 105 5 3 10.2 5.6  
7250 20.4 68.7 085 4 2 10.2 5.6 | 21.4 70.5 105 5 3 10.3 5.6  
7000 21.2 70.2 085 4 2 9.8 5.4 | 22.2 72.0 105 5 3 9.7 5.3  
6750 21.9 71.4 085 4 2 9.8 5.3 | 22.9 73.2 100 5 3 9.4 5.1  
6500 22.7 72.9 085 4 2 10.5 5.8 | 23.6 74.5 100 5 3 10.3 5.7  
6250 23.4 74.1 080 4 2 10.1 5.5 | 24.4 75.9 100 5 3 11.2 6.1  
6000 24.2 75.6 080 4 2 12.0 6.6 | 25.2 77.4 095 5 2 9.5 5.2  
5750 25.3 77.5 080 4 2 19.5 10.7 | 25.9 78.6 095 5 2 12.9 7.1  
5500 27.1 80.8 075 4 2 25.9 14.2 | 27.3 81.1 095 5 2 23.2 12.7  
________________________________________________________________________________  
 
THIS PRODUCT IS ISSUED TWICE PER DAY, ONCE BY APPROXIMATELY 0630 MST/0730 MDT  
(1330 UTC) AND AGAIN BY APPROXIMATELY 1830 MST/1930 MDT (0130 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 OLD STAPLETON  
AIRPORT SITE IN DENVER, COLORADO AT  
 
NORTH LATITUDE: 39 DEG 46 MIN 5.016 SEC  
WEST LONGITUDE: 104 DEG 52 MIN 9.984 SEC  
ELEVATION: 5285 FEET (1611 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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