092  
UXUS97 KGJT 241326  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0726 MDT WEDNESDAY, MAY 24, 2017  
 
THIS FORECAST IS FOR WEDNESDAY, MAY 24, 2017:  
 
IF THE TRIGGER TEMPERATURE OF 71.5 F/21.9 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... GOOD  
MAXIMUM RATE OF LIFT........................ 815 FT/MIN (4.1 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 15466 FT MSL (10627 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 87.0 F/31.0 C  
TIME OF TRIGGER TEMPERATURE.................... 1030 MDT  
TIME OF OVERDEVELOPMENT........................ NONE  
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE  
SURFACE WINDS DURING SOARING WINDOW............ BETWEEN 20 MPH AND 30 MPH  
HEIGHT OF THE -3 THERMAL INDEX................. 13205 FT MSL (8366 FT AGL)  
THERMAL SOARING OUTLOOK FOR THURSDAY 05/25..... EXCELLENT  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 05:54:10 / 20:27:42 MDT  
TOTAL POSSIBLE SUNSHINE........... 14 HR 33 MIN 32 SEC (873 MIN 32 SEC)  
ALTITUDE OF SUN AT 13:11:08 MDT... 71.77 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 05/24/2017 AT 0600 MDT  
 
FREEZING LEVEL.................. 14342 FT MSL (9503 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 19783 FT MSL (14944 FT AGL)  
LIFTED CONDENSATION LEVEL....... 18565 FT MSL (13726 FT AGL)  
LIFTED INDEX.................... +4.1  
K INDEX......................... +1.2  
 
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 -70.7 -95.3 295 22 11 4.3 2.3 78.7 173.6 27.7 M M  
45000 -65.7 -86.3 335 39 20 7.2 3.9 62.3 144.1 19.6 M M  
40000 -56.8 -70.2 330 41 21 6.3 3.4 53.6 128.5 15.3 M M  
38000 -53.0 -63.4 330 40 21 6.9 3.8 50.5 122.9 13.6 M M  
36000 -47.9 -54.2 335 39 20 9.2 5.0 49.3 120.8 13.1 M M  
34000 -42.3 -44.1 340 34 18 7.9 4.3 48.1 118.6 12.6 M M  
32000 -37.8 -36.0 315 37 19 5.8 3.2 46.2 115.1 11.5 M M  
30000 -32.9 -27.2 310 36 18 9.0 4.9 44.9 112.9 10.8 M M  
29000 -30.2 -22.4 325 31 16 9.0 4.9 44.6 112.3 10.8 M M  
28000 -27.5 -17.5 325 30 16 9.0 4.9 44.2 111.6 10.6 M M  
27000 -24.8 -12.6 320 30 15 9.0 4.9 43.9 111.1 10.5 M M  
26000 -22.2 -8.0 320 29 15 9.0 4.9 43.6 110.4 10.3 M M  
25000 -19.5 -3.1 315 29 15 6.4 3.5 43.3 110.0 10.3 M M  
24000 -18.2 -0.8 305 31 16 10.0 5.5 41.3 106.3 8.7 M M  
23000 -16.1 3.0 300 35 18 6.0 3.3 40.3 104.6 8.0 M M  
22000 -14.3 6.3 300 31 16 4.4 2.4 38.9 102.1 6.9 M M  
21000 -13.4 7.9 300 27 14 2.9 1.6 36.5 97.6 4.9 M M  
20000 -11.7 10.9 300 23 12 7.9 4.3 35.1 95.2 3.8 M M  
19500 -10.6 12.9 300 23 12 6.1 3.4 34.6 94.4 3.4 M M  
19000 -9.7 14.5 295 23 12 7.2 3.9 34.0 93.3 2.8 M M  
18500 -7.9 17.8 300 24 12 7.6 4.1 33.6 92.4 2.4 M M  
18000 -6.8 19.8 305 25 13 7.6 4.2 33.2 91.7 2.1 M M  
17500 -5.6 21.9 310 26 13 7.6 4.2 32.8 91.1 1.9 M M  
17000 -4.5 23.9 315 27 14 7.2 4.0 32.5 90.5 1.6 M M  
16500 -3.5 25.7 315 28 14 6.4 3.5 32.0 89.6 1.1 M M  
16000 -2.6 27.3 320 29 15 6.5 3.6 31.4 88.6 0.6 M M  
15500 -1.7 28.9 320 28 14 4.2 2.3 30.7 87.3 -0.1 812 4.1  
15000 -1.2 29.8 320 27 14 5.2 2.9 29.8 85.6 -1.0 781 4.0  
14500 -0.2 31.6 315 26 13 6.0 3.3 29.2 84.5 -1.5 736 3.7  
14000 0.8 33.4 315 25 13 5.9 3.3 28.6 83.4 -1.9 692 3.5  
13500 1.6 34.9 310 22 11 5.0 2.7 27.8 82.1 -2.6 654 3.3  
13000 2.5 36.5 305 20 10 5.7 3.1 27.2 80.9 -3.2 612 3.1  
12500 2.6 36.7 300 17 9 2.1 1.2 25.8 78.5 -4.5 593 3.0  
12000 3.5 38.3 295 15 8 5.8 3.2 25.3 77.5 -5.1 552 2.8  
11500 4.1 39.4 285 15 8 6.8 3.7 24.5 76.2 -6.1 520 2.6  
11000 5.2 41.4 280 16 8 8.4 4.6 24.3 75.7 -6.4 471 2.4  
10500 6.2 43.2 275 16 8 5.7 3.1 23.9 75.1 -6.9 425 2.2  
10250 6.7 44.1 270 17 9 6.0 3.3 23.6 74.5 -7.2 405 2.1  
10000 7.2 45.0 270 17 9 7.5 4.1 23.4 74.1 -7.4 382 1.9  
9750 7.8 46.0 265 17 9 7.7 4.2 23.2 73.8 -7.6 357 1.8  
9500 8.3 46.9 265 17 9 7.6 4.2 23.1 73.5 -7.8 333 1.7  
9250 8.9 48.0 260 18 9 7.7 4.2 22.9 73.2 -8.0 308 1.6  
9000 9.5 49.1 260 18 9 7.7 4.2 22.7 72.9 -8.1 284 1.4  
8750 10.0 50.0 260 15 8 7.6 4.2 22.6 72.6 -8.3 259 1.3  
8500 10.6 51.1 265 12 6 7.7 4.2 22.4 72.3 -8.5 235 1.2  
8250 11.2 52.2 265 9 4 7.5 4.1 22.2 72.0 -8.7 210 1.1  
8000 11.8 53.2 275 6 3 8.1 4.4 22.1 71.7 -8.9 186 0.9  
7750 12.3 54.1 235 4 2 6.0 3.3 21.9 71.4 -9.0 161 0.8  
7500 12.7 54.9 190 5 3 3.6 2.0 21.5 70.7 -9.5 143 0.7  
7250 13.0 55.4 170 9 4 3.7 2.0 21.0 69.8 -9.9 127 0.6  
7000 13.0 55.4 160 12 6 -5.6 -3.1 20.3 68.6 -10.6 118 0.6  
6750 12.4 54.3 160 11 6 -5.7 -3.1 18.9 66.0 -12.0 130 0.7  
6500 12.4 54.3 155 9 5 3.8 2.1 18.2 64.7 -12.7 121 0.6  
6250 12.7 54.9 145 7 3 4.3 2.4 17.8 64.0 -13.2 105 0.5  
6000 13.0 55.4 130 4 2 4.2 2.3 17.3 63.2 -13.6 88 0.4  
5750 13.3 55.9 125 4 2 4.1 2.3 16.9 62.5 -14.1 72 0.4  
5500 13.6 56.5 120 4 2 4.5 2.5 16.5 61.7 -14.6 55 0.3  
5250 13.5 56.3 115 4 2 -13.6 -7.5 15.7 60.2 -15.5 52 0.3  
5000 11.4 52.5 115 4 2 -37.3 -20.4 12.8 55.1 -18.4 108 0.5  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
05/24/2017 AT 0900 MDT | 05/24/2017 AT 1200 MDT  
|  
K INDEX... -7.7 LI... +3.8 | K INDEX... +5.3 LI... +2.8  
CAPE... 0.0 CIN... 0.0 | CAPE... 0.0 CIN... 0.0  
|  
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 -67.5 -89.5 325 19 10 -0.4 -0.2 | -67.4 -89.3 280 22 12 -0.7 -0.4  
45000 -66.0 -86.8 310 26 14 6.4 3.5 | -66.2 -87.2 275 29 15 6.8 3.7  
40000 -56.3 -69.3 325 29 15 7.3 4.0 | -55.9 -68.6 280 33 17 7.4 4.1  
38000 -51.8 -61.2 325 26 13 7.5 4.1 | -51.4 -60.5 280 28 14 7.6 4.2  
36000 -47.2 -53.0 325 23 12 7.5 4.1 | -46.8 -52.2 280 23 12 7.6 4.2  
34000 -42.5 -44.5 315 23 12 8.0 4.4 | -42.0 -43.6 275 23 12 8.0 4.4  
32000 -37.7 -35.9 310 26 13 8.0 4.4 | -36.6 -33.9 275 24 12 8.0 4.4  
30000 -32.1 -25.8 300 28 14 8.5 4.7 | -31.7 -25.1 275 26 14 8.1 4.4  
29000 -29.6 -21.3 300 28 15 8.5 4.7 | -29.3 -20.7 275 27 14 8.1 4.4  
28000 -27.0 -16.6 295 29 15 8.6 4.7 | -26.9 -16.4 275 28 15 8.3 4.6  
27000 -24.7 -12.5 295 30 15 7.5 4.1 | -24.9 -12.8 280 30 15 6.1 3.3  
26000 -22.4 -8.3 295 30 16 7.6 4.1 | -23.1 -9.6 280 31 16 6.1 3.4  
25000 -20.2 -4.4 290 31 16 7.5 4.1 | -21.2 -6.2 280 33 17 6.1 3.4  
24000 -18.2 -0.8 295 31 16 5.7 3.1 | -19.4 -2.9 285 34 18 6.2 3.4  
23000 -16.5 2.3 295 30 16 5.7 3.1 | -17.5 0.5 285 34 18 6.2 3.4  
22000 -14.8 5.4 300 30 15 5.7 3.1 | -15.7 3.7 285 35 18 6.2 3.4  
21000 -13.3 8.1 300 29 15 4.9 2.7 | -13.9 7.0 290 34 17 6.0 3.3  
20000 -11.8 10.8 305 28 14 4.9 2.7 | -12.1 10.2 290 31 16 6.0 3.3  
19500 -11.1 12.0 305 28 14 4.9 2.7 | -11.2 11.8 290 30 16 6.0 3.3  
19000 -10.4 13.3 305 27 14 5.3 2.9 | -10.3 13.5 290 29 15 6.1 3.3  
18500 -9.5 14.9 305 27 14 6.5 3.5 | -9.3 15.3 290 28 15 6.6 3.6  
18000 -8.6 16.5 305 26 13 6.4 3.5 | -8.3 17.1 290 27 14 6.6 3.6  
17500 -7.6 18.3 305 26 13 6.9 3.8 | -7.3 18.9 290 27 14 6.6 3.6  
17000 -6.5 20.3 305 25 13 7.0 3.9 | -6.3 20.7 290 26 14 6.6 3.6  
16500 -5.4 22.3 300 25 13 7.3 4.0 | -5.4 22.3 290 26 13 6.6 3.6  
16000 -4.3 24.3 300 25 13 7.9 4.3 | -4.4 24.1 290 26 13 6.5 3.6  
15500 -3.0 26.6 300 24 13 8.1 4.5 | -3.4 25.9 290 26 13 6.6 3.6  
15000 -2.0 28.4 300 25 13 6.0 3.3 | -2.1 28.2 290 28 14 6.4 3.5  
14500 -0.6 30.9 300 25 13 6.2 3.4 | -1.2 29.8 295 29 15 6.8 3.7  
14000 0.3 32.5 305 26 14 6.3 3.4 | -0.3 31.5 295 30 15 7.1 3.9  
13500 1.2 34.2 305 28 14 6.5 3.6 | 0.7 33.3 295 30 16 7.1 3.9  
13000 2.1 35.8 305 29 15 6.6 3.6 | 1.8 35.2 295 30 15 9.0 4.9  
12500 3.0 37.4 305 29 15 6.7 3.7 | 3.1 37.6 290 28 14 8.8 4.8  
12000 4.0 39.2 305 29 15 8.1 4.5 | 4.4 39.9 290 26 14 8.9 4.9  
11500 5.2 41.4 305 28 14 8.2 4.5 | 5.8 42.4 290 24 13 9.0 4.9  
11000 6.3 43.3 305 26 13 7.0 3.8 | 7.1 44.8 285 22 12 8.0 4.4  
10500 7.3 45.1 300 23 12 7.1 3.9 | 8.2 46.8 280 20 10 9.0 4.9  
10250 7.9 46.2 300 21 11 9.0 4.9 | 9.0 48.2 280 19 10 10.1 5.5  
10000 8.5 47.3 295 20 10 7.9 4.3 | 9.6 49.3 275 18 9 8.0 4.4  
9750 9.0 48.2 295 18 9 5.6 3.1 | 10.2 50.4 275 17 9 7.0 3.9  
9500 9.5 49.1 290 17 9 7.2 3.9 | 10.7 51.3 270 17 9 7.6 4.2  
9250 9.9 49.8 290 15 8 3.2 1.8 | 11.3 52.3 265 16 8 6.3 3.4  
9000 10.0 50.0 285 14 7 1.9 1.0 | 11.7 53.1 265 14 7 5.5 3.0  
8750 10.3 50.5 280 13 7 4.6 2.5 | 12.1 53.8 260 12 6 6.1 3.4  
8500 10.6 51.1 275 12 6 3.9 2.1 | 12.5 54.5 250 11 5 6.0 3.3  
8250 10.9 51.6 270 11 5 4.6 2.5 | 13.0 55.4 245 9 5 6.0 3.3  
8000 11.2 52.2 265 10 5 4.6 2.5 | 13.4 56.1 240 8 4 7.4 4.1  
7750 11.5 52.7 260 8 4 4.5 2.5 | 14.0 57.2 235 7 4 8.4 4.6  
7500 11.9 53.4 250 7 4 4.1 2.3 | 14.6 58.3 230 7 4 8.5 4.7  
7250 12.1 53.8 240 6 3 2.8 1.6 | 15.3 59.5 230 7 3 10.2 5.6  
7000 12.3 54.1 225 5 3 3.2 1.7 | 16.1 61.0 230 7 3 10.5 5.8  
6750 12.6 54.7 205 5 3 3.7 2.0 | 16.8 62.2 230 6 3 9.6 5.3  
6500 12.9 55.2 195 6 3 6.0 3.3 | 17.6 63.7 230 6 3 10.4 5.7  
6250 13.5 56.3 190 6 3 7.8 4.3 | 18.4 65.1 230 6 3 11.4 6.2  
6000 14.0 57.2 185 6 3 7.6 4.2 | 19.2 66.6 230 6 3 11.0 6.0  
5750 14.7 58.5 180 6 3 9.5 5.2 | 20.0 68.0 230 6 3 11.6 6.4  
5500 15.4 59.7 180 6 3 11.0 6.0 | 21.0 69.8 230 6 3 15.0 8.2  
5250 16.2 61.2 180 6 3 10.6 5.8 | 22.3 72.1 230 6 3 18.5 10.1  
5000 M M M M M M M | M M M M M M M  
 
05/24/2017 AT 1500 MDT | 05/24/2017 AT 1800 MDT  
|  
K INDEX... +8.9 LI... +0.5 | K INDEX... +19.2 LI... -0.4  
CAPE... 0.0 CIN... 0.0 | CAPE... +18.4 CIN... -23.6  
|  
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 -68.1 -90.6 255 18 9 -0.0 -0.0 | -66.2 -87.2 240 25 13 -0.2 -0.1  
45000 -66.1 -87.0 245 35 18 6.6 3.6 | -64.9 -84.8 245 40 20 5.9 3.2  
40000 -56.1 -69.0 250 39 20 7.4 4.1 | -56.1 -69.0 250 47 24 6.5 3.6  
38000 -51.4 -60.5 245 37 19 7.9 4.3 | -51.7 -61.1 250 47 24 7.4 4.1  
36000 -46.7 -52.1 240 35 18 7.9 4.3 | -47.2 -53.0 250 47 24 7.4 4.1  
34000 -42.0 -43.6 240 34 18 7.9 4.3 | -42.6 -44.7 250 47 24 7.8 4.3  
32000 -37.3 -35.1 245 33 17 7.9 4.3 | -37.9 -36.2 250 46 24 7.8 4.3  
30000 -32.2 -26.0 250 35 18 7.3 4.0 | -33.2 -27.8 255 44 23 6.1 3.4  
29000 -30.0 -22.0 255 36 18 7.3 4.0 | -31.4 -24.5 255 43 22 6.1 3.4  
28000 -27.8 -18.0 255 37 19 7.4 4.1 | -29.5 -21.1 255 42 22 6.1 3.4  
27000 -25.8 -14.4 260 37 19 6.2 3.4 | -27.6 -17.7 255 40 21 6.7 3.7  
26000 -24.0 -11.2 265 36 18 6.2 3.4 | -25.6 -14.1 260 37 19 6.7 3.7  
25000 -22.1 -7.8 275 35 18 6.2 3.4 | -23.6 -10.5 260 34 18 6.7 3.7  
24000 -20.2 -4.4 275 34 18 6.4 3.5 | -21.6 -6.9 265 33 17 6.2 3.4  
23000 -18.3 -0.9 280 33 17 6.4 3.5 | -19.8 -3.6 270 33 17 6.2 3.4  
22000 -16.4 2.5 280 31 16 6.4 3.5 | -17.9 -0.2 275 33 17 6.3 3.4  
21000 -14.6 5.7 280 30 15 5.5 3.0 | -16.0 3.2 275 33 17 6.9 3.8  
20000 -13.0 8.6 280 29 15 5.5 3.0 | -14.0 6.8 275 34 17 7.0 3.8  
19500 -12.1 10.2 275 29 15 5.5 3.0 | -12.9 8.8 275 34 17 7.1 3.9  
19000 -11.3 11.7 275 28 15 5.8 3.2 | -11.9 10.6 275 34 17 7.2 4.0  
18500 -10.2 13.6 275 28 15 8.2 4.5 | -10.7 12.7 275 34 17 9.1 5.0  
18000 -9.0 15.8 270 28 15 8.0 4.4 | -9.4 15.1 270 33 17 9.0 4.9  
17500 -7.8 18.0 270 28 15 7.7 4.2 | -8.1 17.4 270 33 17 9.0 4.9  
17000 -6.7 19.9 270 28 15 7.6 4.2 | -6.7 19.9 270 32 17 9.1 5.0  
16500 -5.6 21.9 270 28 15 7.7 4.2 | -5.4 22.3 265 32 16 9.1 5.0  
16000 -4.4 24.1 270 28 15 7.8 4.3 | -4.1 24.6 265 32 16 9.0 4.9  
15500 -3.3 26.1 270 28 15 7.8 4.3 | -2.8 27.0 265 32 16 9.0 5.0  
15000 -2.2 28.0 270 28 14 7.8 4.3 | -1.5 29.3 265 32 16 8.8 4.8  
14500 -0.5 31.1 270 28 14 7.9 4.4 | 0.5 32.9 260 31 16 8.9 4.9  
14000 0.6 33.1 270 28 14 7.8 4.3 | 1.9 35.4 260 31 16 9.8 5.4  
13500 1.7 35.1 270 28 14 7.8 4.3 | 3.3 37.9 260 31 16 9.8 5.4  
13000 3.0 37.4 270 27 14 9.4 5.2 | 4.7 40.5 260 30 16 9.2 5.1  
12500 4.3 39.7 265 27 14 9.3 5.1 | 6.1 43.0 260 30 15 9.2 5.1  
12000 5.7 42.3 265 26 13 9.3 5.1 | 7.5 45.5 255 29 15 9.3 5.1  
11500 7.0 44.6 265 25 13 9.4 5.2 | 8.8 47.8 255 28 15 9.3 5.1  
11000 8.4 47.1 265 24 13 8.5 4.6 | 10.2 50.4 255 27 14 8.8 4.8  
10500 9.6 49.3 260 24 12 9.4 5.2 | 11.5 52.7 255 26 13 9.3 5.1  
10250 10.4 50.7 260 23 12 11.0 6.0 | 12.2 54.0 255 26 13 10.3 5.7  
10000 11.2 52.2 260 22 11 9.6 5.3 | 13.0 55.4 255 25 13 9.9 5.4  
9750 11.8 53.2 260 20 10 8.9 4.9 | 13.7 56.7 255 23 12 9.4 5.2  
9500 12.5 54.5 260 19 10 9.1 5.0 | 14.4 57.9 255 22 11 10.0 5.5  
9250 13.2 55.8 260 17 9 9.0 4.9 | 15.1 59.2 255 20 10 8.0 4.4  
9000 13.8 56.8 260 16 8 9.4 5.2 | 15.7 60.3 255 19 10 7.7 4.2  
8750 14.6 58.3 260 16 8 9.8 5.4 | 16.3 61.3 255 18 9 9.6 5.2  
8500 15.3 59.5 255 15 8 9.3 5.1 | 17.0 62.6 255 17 9 8.6 4.7  
8250 16.0 60.8 255 15 7 11.0 6.0 | 17.7 63.9 255 16 8 10.7 5.9  
8000 16.9 62.4 255 14 7 10.6 5.8 | 18.6 65.5 255 16 8 10.6 5.8  
7750 17.5 63.5 255 14 7 8.7 4.8 | 19.2 66.6 255 15 8 8.6 4.7  
7500 18.2 64.8 255 14 7 9.1 5.0 | 19.9 67.8 255 15 8 9.0 4.9  
7250 18.9 66.0 255 14 7 10.2 5.6 | 20.6 69.1 255 15 8 9.5 5.2  
7000 19.7 67.5 255 13 7 10.7 5.9 | 21.3 70.3 260 14 7 10.3 5.6  
6750 20.5 68.9 255 13 7 9.6 5.3 | 22.1 71.8 260 14 7 10.1 5.6  
6500 21.2 70.2 255 13 7 10.2 5.6 | 22.9 73.2 260 14 7 10.1 5.6  
6250 22.0 71.6 255 13 7 11.1 6.1 | 23.6 74.5 260 13 7 10.6 5.8  
6000 22.9 73.2 255 12 6 12.0 6.6 | 24.4 75.9 260 13 7 10.7 5.9  
5750 23.8 74.8 255 12 6 12.1 6.7 | 25.2 77.4 260 12 6 9.9 5.4  
5500 24.7 76.5 255 11 6 14.7 8.1 | 25.9 78.6 260 11 6 9.9 5.5  
5250 26.0 78.8 255 11 6 19.9 10.9 | 26.7 80.1 260 11 6 10.9 6.0  
5000 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) 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 AT WALKER FIELD IN GRAND  
JUNCTION, COLORADO AT  
 
NORTH LATITUDE: 39 DEG 07 MIN 00.001 SEC  
WEST LONGITUDE: 108 DEG 31 MIN 59.998 SEC  
ELEVATION: 4839 FEET (1475 METERS)  
 
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE WESTERN SLOPE OF  
COLORADO. 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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