715  
UXUS97 KGJT 181358  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0758 MDT SATURDAY, AUGUST 18, 2018  
 
THIS FORECAST IS FOR SATURDAY, AUGUST 18, 2018:  
 
IF THE TRIGGER TEMPERATURE OF 79.8 F/26.5 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... EXCELLENT  
MAXIMUM RATE OF LIFT........................ 964 FT/MIN (4.9 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 16058 FT MSL (11219 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 90.0 F/32.7 C  
TIME OF TRIGGER TEMPERATURE.................... 1245 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................. 12790 FT MSL (7950 FT AGL)  
THERMAL SOARING OUTLOOK FOR SUNDAY 08/19....... GOOD  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
***ATTENTION SOARING FORECAST USERS***THE NATIONAL WEATHER SERVICE IN BOULDER WANTS TO HEAR FROM YOU.  
PLEASE SEND AND EMAIL TO PAUL.T.SCHLATTER@NOAA.GOV AND LET US KNOW HOW YOU USE THE SOARING FORECAST. THANKS!  
 
SUNRISE/SUNSET.................... 06:30:23 / 20:05:30 MDT  
TOTAL POSSIBLE SUNSHINE........... 13 HR 35 MIN 7 SEC (815 MIN 7 SEC)  
ALTITUDE OF SUN AT 13:17:57 MDT... 63.52 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 08/18/2018 AT 0600 MDT  
 
FREEZING LEVEL.................. 15423 FT MSL (10584 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 14449 FT MSL (9610 FT AGL)  
LIFTED CONDENSATION LEVEL....... 14836 FT MSL (9997 FT AGL)  
LIFTED INDEX.................... -1.9  
K INDEX......................... +26.5  
 
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 -64.4 -83.9 280 23 12 5.1 2.8 87.3 189.1 31.9 M M  
45000 -60.9 -77.6 260 62 32 7.3 4.0 67.4 153.3 21.9 M M  
40000 -51.6 -60.9 255 63 33 9.4 5.2 59.1 138.3 17.9 M M  
38000 -47.2 -53.0 260 62 32 8.7 4.8 56.9 134.5 16.9 M M  
36000 -43.8 -46.8 270 58 30 2.9 1.6 53.4 128.2 14.9 M M  
34000 -39.8 -39.6 270 45 23 8.0 4.4 50.9 123.5 13.4 M M  
32000 -34.3 -29.7 275 30 16 8.3 4.6 49.5 121.1 12.8 M M  
30000 -29.5 -21.1 285 23 12 7.9 4.3 48.1 118.6 12.0 M M  
29000 -27.2 -17.0 275 24 12 7.0 3.9 47.3 117.1 11.5 M M  
28000 -24.9 -12.8 270 25 13 8.0 4.4 46.5 115.8 11.0 M M  
27000 -22.6 -8.7 260 27 14 6.8 3.7 45.8 114.4 10.5 M M  
26000 -20.4 -4.7 255 29 15 10.2 5.6 45.0 112.9 9.9 M M  
25000 -17.8 -0.0 250 31 16 7.2 3.9 44.7 112.5 9.8 M M  
24000 -15.8 3.6 255 34 17 6.6 3.6 43.6 110.5 8.9 M M  
23000 -13.9 7.0 245 28 14 6.6 3.6 42.3 108.2 7.9 M M  
22000 -12.0 10.4 225 23 12 6.0 3.3 41.2 106.2 7.0 M M  
21000 -10.3 13.5 225 22 11 5.7 3.2 39.7 103.5 5.8 M M  
20000 -8.7 16.3 230 21 11 5.8 3.2 38.3 101.0 4.6 M M  
19500 -7.8 18.0 230 22 11 5.8 3.2 37.6 99.7 4.0 M M  
19000 -7.0 19.4 225 24 12 5.4 3.0 36.9 98.4 3.4 M M  
18500 -6.2 20.8 220 22 11 5.5 3.0 36.1 97.1 2.7 M M  
18000 -5.5 22.1 215 20 10 5.5 3.0 35.4 95.7 2.1 M M  
17500 -4.2 24.4 205 16 8 7.0 3.8 34.5 94.0 1.2 M M  
17000 -3.2 26.2 200 15 8 6.9 3.8 34.0 93.1 0.8 M M  
16500 -2.2 28.0 205 15 8 6.8 3.8 33.5 92.2 0.3 M M  
16000 -1.2 29.8 205 15 8 6.7 3.7 33.0 91.4 -0.1 950 4.8  
15500 0.0 32.0 210 16 8 9.4 5.1 32.7 90.8 -0.4 900 4.6  
15000 1.4 34.5 215 17 9 9.1 5.0 32.6 90.6 -0.6 845 4.3  
14500 2.7 36.9 220 19 10 9.1 5.0 32.5 90.5 -0.7 790 4.0  
14000 4.1 39.4 225 20 10 8.3 4.6 32.4 90.3 -0.7 735 3.7  
13500 4.9 40.8 230 20 11 4.9 2.7 31.8 89.2 -1.4 695 3.5  
13000 5.3 41.5 235 20 11 0.1 0.0 30.7 87.2 -2.4 667 3.4  
12500 5.1 41.2 260 16 8 1.1 0.6 29.0 84.1 -4.2 660 3.4  
12000 6.0 42.8 290 16 8 9.5 5.2 28.5 83.2 -4.7 618 3.1  
11500 7.3 45.1 295 14 7 9.1 5.0 28.3 83.0 -4.8 563 2.9  
11000 8.7 47.7 300 13 7 9.1 5.0 28.2 82.8 -5.0 508 2.6  
10500 10.0 50.0 310 13 7 10.1 5.5 28.1 82.6 -5.1 453 2.3  
10250 10.9 51.6 330 13 7 10.0 5.5 28.2 82.8 -5.0 420 2.1  
10000 11.5 52.7 345 14 7 8.6 4.7 28.2 82.7 -5.1 393 2.0  
9750 12.2 54.0 345 14 7 9.0 4.9 28.1 82.6 -5.2 366 1.9  
9500 12.8 55.0 345 14 7 8.9 4.9 28.0 82.5 -5.2 339 1.7  
9250 13.5 56.3 345 14 7 8.9 4.9 28.0 82.4 -5.3 312 1.6  
9000 14.1 57.4 345 14 7 8.9 4.9 27.9 82.3 -5.4 285 1.4  
8750 14.8 58.6 345 14 7 8.9 4.9 27.9 82.2 -5.5 258 1.3  
8500 15.5 59.9 345 13 7 8.9 4.9 27.8 82.0 -5.6 231 1.2  
8250 16.1 61.0 350 13 6 8.9 4.9 27.7 81.9 -5.7 204 1.0  
8000 16.8 62.2 350 12 6 8.9 4.9 27.7 81.8 -5.7 177 0.9  
7750 17.4 63.3 355 12 6 8.9 4.9 27.6 81.7 -5.8 150 0.8  
7500 18.1 64.6 355 11 6 9.0 4.9 27.5 81.6 -5.9 123 0.6  
7250 18.7 65.7 360 11 6 8.8 4.8 27.5 81.4 -6.0 96 0.5  
7000 19.4 66.9 005 11 6 9.4 5.1 27.4 81.3 -6.1 69 0.3  
6750 20.0 68.0 360 11 6 6.4 3.5 27.3 81.2 -6.2 42 0.2  
6500 20.3 68.5 360 11 6 3.8 2.1 26.9 80.4 -6.7 26 0.1  
6250 20.6 69.1 355 11 6 4.1 2.3 26.5 79.7 -7.1 11 0.1  
6000 20.9 69.6 350 11 6 5.6 3.0 26.1 78.9 -7.6 M M  
5750 21.1 70.0 340 10 5 -0.4 -0.2 25.7 78.2 -8.1 M M  
5500 20.6 69.1 330 10 5 -10.1 -5.5 24.4 76.0 -9.4 M M  
5250 19.9 67.8 315 10 5 -4.3 -2.4 23.1 73.5 -10.8 2 0.0  
5000 20.2 68.4 305 11 6 10.2 5.6 22.6 72.6 -11.3 M M  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
08/18/2018 AT 0900 MDT | 08/18/2018 AT 1200 MDT  
|  
CAPE... +189.8 LI... -1.7 | CAPE... +666.7 LI... -2.1  
CINH... -101.2 K INDEX... +29.8 | CINH... -18.1 K INDEX... +22.1  
|  
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 -64.0 -83.2 275 17 9 1.2 0.7 | -63.5 -82.3 280 15 8 1.5 0.8  
45000 -59.5 -75.1 265 28 14 6.2 3.4 | -58.6 -73.5 275 25 13 6.4 3.5  
40000 -50.1 -58.2 260 31 16 6.2 3.4 | -49.2 -56.6 265 30 16 4.9 2.7  
38000 -46.4 -51.5 260 30 15 6.2 3.4 | -46.3 -51.3 265 27 14 4.9 2.7  
36000 -42.7 -44.9 260 28 15 6.3 3.4 | -43.3 -45.9 265 24 13 4.9 2.7  
34000 -39.2 -38.6 260 24 12 5.7 3.1 | -39.9 -39.8 270 21 11 5.8 3.2  
32000 -35.4 -31.7 260 19 10 5.9 3.2 | -36.0 -32.8 275 18 9 5.7 3.1  
30000 -30.9 -23.6 260 17 9 7.7 4.2 | -31.6 -24.9 280 17 9 7.7 4.2  
29000 -28.6 -19.5 260 16 8 7.7 4.2 | -29.3 -20.7 280 16 8 7.7 4.2  
28000 -26.4 -15.5 260 16 8 7.3 4.0 | -27.0 -16.6 280 16 8 7.6 4.2  
27000 -24.2 -11.6 260 16 8 7.3 4.0 | -24.7 -12.5 280 16 8 7.6 4.2  
26000 -22.0 -7.6 260 16 8 7.3 4.0 | -22.4 -8.3 280 15 8 7.6 4.2  
25000 -19.9 -3.8 260 15 8 7.4 4.0 | -20.1 -4.2 280 15 7 7.6 4.2  
24000 -17.7 0.1 260 15 8 7.4 4.1 | -17.9 -0.2 275 14 7 7.5 4.1  
23000 -15.6 3.9 260 15 8 7.4 4.1 | -15.7 3.7 275 14 7 7.5 4.1  
22000 -13.4 7.9 260 15 8 7.2 3.9 | -13.4 7.9 275 14 7 7.3 4.0  
21000 -11.5 11.3 265 14 7 6.6 3.6 | -11.4 11.5 275 14 7 6.8 3.7  
20000 -9.1 15.6 265 14 7 6.6 3.6 | -9.4 15.1 275 14 7 6.8 3.7  
19500 -8.2 17.2 265 14 7 6.7 3.7 | -7.9 17.8 275 14 7 6.5 3.6  
19000 -7.2 19.0 265 13 7 6.8 3.8 | -7.0 19.4 275 14 7 6.1 3.3  
18500 -6.2 20.8 270 13 7 6.9 3.8 | -6.1 21.0 275 14 7 6.1 3.4  
18000 -5.2 22.6 270 13 6 6.7 3.7 | -5.2 22.6 275 13 7 6.0 3.3  
17500 -4.2 24.4 270 12 6 6.8 3.7 | -4.4 24.1 280 13 7 6.1 3.3  
17000 -3.3 26.1 270 12 6 6.8 3.7 | -3.5 25.7 280 12 6 6.4 3.5  
16500 -2.3 27.9 270 12 6 6.8 3.7 | -2.5 27.5 280 12 6 6.8 3.7  
16000 -1.3 29.7 275 11 6 6.8 3.7 | -1.6 29.1 285 11 6 6.9 3.8  
15500 -0.3 31.5 275 11 6 7.0 3.8 | -0.6 30.9 285 11 6 7.2 4.0  
15000 0.7 33.3 275 11 5 7.0 3.8 | 0.4 32.7 290 10 5 7.3 4.0  
14500 1.6 34.9 275 10 5 6.8 3.8 | 1.4 34.5 290 10 5 7.4 4.0  
14000 2.6 36.7 275 10 5 6.9 3.8 | 2.4 36.3 295 10 5 7.5 4.1  
13500 3.6 38.5 275 9 5 7.0 3.9 | 3.5 38.3 295 9 5 7.4 4.1  
13000 4.6 40.3 270 9 4 7.2 3.9 | 4.5 40.1 295 9 5 7.5 4.1  
12500 5.6 42.1 270 8 4 7.2 3.9 | 5.5 41.9 300 9 4 7.5 4.1  
12000 6.7 44.1 270 8 4 7.2 4.0 | 6.5 43.7 300 8 4 7.5 4.1  
11500 7.7 45.9 270 7 4 7.4 4.1 | 7.5 45.5 300 7 4 7.7 4.2  
11000 8.8 47.8 265 6 3 7.8 4.3 | 8.7 47.7 295 7 4 8.0 4.4  
10500 9.9 49.8 265 5 3 7.5 4.1 | 9.8 49.6 295 6 3 6.2 3.4  
10250 10.4 50.7 265 5 3 7.1 3.9 | 10.2 50.4 295 6 3 7.3 4.0  
10000 11.0 51.8 265 4 2 7.2 4.0 | 10.9 51.6 295 6 3 10.5 5.8  
9750 11.5 52.7 260 4 2 7.4 4.1 | 11.6 52.9 290 6 3 9.9 5.4  
9500 12.0 53.6 255 3 2 6.6 3.6 | 12.4 54.3 290 5 3 9.3 5.1  
9250 12.5 54.5 245 3 1 5.6 3.0 | 13.0 55.4 290 5 3 8.4 4.6  
9000 12.9 55.2 235 2 1 6.0 3.3 | 13.6 56.5 285 5 3 9.3 5.1  
8750 13.3 55.9 220 2 1 6.3 3.5 | 14.4 57.9 290 5 2 10.1 5.5  
8500 13.8 56.8 200 1 1 5.9 3.2 | 15.1 59.2 290 4 2 8.9 4.9  
8250 14.2 57.6 160 1 1 5.6 3.1 | 15.6 60.1 285 4 2 7.5 4.1  
8000 14.6 58.3 130 1 1 5.7 3.1 | 16.2 61.2 285 4 2 8.8 4.8  
7750 15.0 59.0 110 2 1 5.7 3.1 | 16.9 62.4 285 3 2 9.8 5.4  
7500 15.4 59.7 095 2 1 6.0 3.3 | 17.6 63.7 290 3 2 9.0 4.9  
7250 15.9 60.6 090 3 1 6.1 3.4 | 18.2 64.8 290 3 1 8.0 4.4  
7000 16.3 61.3 085 3 2 6.2 3.4 | 18.8 65.8 290 3 1 9.4 5.2  
6750 16.8 62.2 085 3 2 7.0 3.9 | 19.6 67.3 290 3 1 11.4 6.2  
6500 17.3 63.1 085 3 2 7.6 4.2 | 20.4 68.7 290 3 1 10.4 5.7  
6250 17.8 64.0 085 3 2 7.6 4.2 | 21.1 70.0 290 2 1 9.5 5.2  
6000 18.9 66.0 085 3 2 10.6 5.8 | 22.7 72.9 290 2 1 15.9 8.7  
5750 19.9 67.8 085 3 2 17.9 9.8 | 24.3 75.7 290 2 1 26.9 14.7  
5500 20.9 69.6 085 2 1 4.5 2.5 | 25.9 78.6 295 2 1 7.2 4.0  
5250 M M M M M M M | M M M M M M M  
5000 M M M M M M M | M M M M M M M  
 
08/18/2018 AT 1500 MDT | 08/18/2018 AT 1800 MDT  
|  
CAPE... +253.0 LI... -0.4 | CAPE... +56.2 LI... -0.7  
CINH... -16.8 K INDEX... +22.8 | CINH... -16.5 K INDEX... +25.6  
|  
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 -62.7 -80.9 285 14 7 2.0 1.1 | -62.0 -79.6 290 14 7 2.2 1.2  
45000 -57.5 -71.5 280 22 11 5.9 3.3 | -57.1 -70.8 285 21 11 5.0 2.8  
40000 -48.9 -56.0 275 29 15 4.4 2.4 | -49.7 -57.5 290 26 14 4.3 2.4  
38000 -46.3 -51.3 280 26 14 4.3 2.4 | -47.1 -52.8 295 27 14 4.3 2.4  
36000 -43.7 -46.7 280 24 12 4.2 2.3 | -44.5 -48.1 300 27 14 4.2 2.3  
34000 -39.9 -39.8 285 21 11 5.9 3.2 | -40.9 -41.6 305 26 13 6.5 3.6  
32000 -36.4 -33.5 290 19 10 5.8 3.2 | -36.5 -33.7 305 24 13 6.3 3.5  
30000 -31.7 -25.1 290 19 10 8.0 4.4 | -31.8 -25.2 305 23 12 8.0 4.4  
29000 -29.3 -20.7 290 18 10 8.0 4.4 | -29.4 -20.9 305 22 11 8.0 4.4  
28000 -26.9 -16.4 290 18 9 7.7 4.2 | -27.1 -16.8 305 21 11 8.0 4.4  
27000 -24.6 -12.3 290 18 9 7.7 4.2 | -24.6 -12.3 305 20 10 8.1 4.4  
26000 -22.3 -8.1 290 17 9 7.7 4.2 | -22.2 -8.0 305 20 10 8.1 4.4  
25000 -20.0 -4.0 290 17 9 7.6 4.2 | -19.8 -3.6 305 19 10 7.9 4.4  
24000 -17.9 -0.2 290 16 8 7.3 4.0 | -17.7 0.1 305 19 10 7.0 3.8  
23000 -15.7 3.7 285 15 8 7.3 4.0 | -15.6 3.9 305 18 9 7.0 3.8  
22000 -13.5 7.7 285 14 7 7.2 3.9 | -13.5 7.7 300 17 9 6.6 3.6  
21000 -11.5 11.3 285 14 7 6.9 3.8 | -11.9 10.6 300 17 9 5.5 3.0  
20000 -9.4 15.1 285 14 7 6.9 3.8 | -10.0 14.0 295 16 8 5.7 3.1  
19500 -7.9 17.8 290 14 7 6.6 3.6 | -9.2 15.4 295 16 8 6.0 3.3  
19000 -7.0 19.4 290 14 7 6.2 3.4 | -8.3 17.1 295 15 8 6.3 3.4  
18500 -6.1 21.0 290 14 7 6.3 3.5 | -7.4 18.7 295 15 8 6.3 3.4  
18000 -5.2 22.6 295 13 7 5.7 3.1 | -6.5 20.3 295 14 7 7.3 4.0  
17500 -4.4 24.1 295 13 7 5.8 3.2 | -5.5 22.1 295 14 7 7.4 4.1  
17000 -3.6 25.5 295 13 7 6.0 3.3 | -4.4 24.1 295 13 7 7.9 4.3  
16500 -2.7 27.1 300 12 6 6.1 3.3 | -3.2 26.2 300 12 6 8.6 4.7  
16000 -1.9 28.6 300 12 6 6.1 3.4 | -2.0 28.4 300 12 6 8.6 4.7  
15500 -0.9 30.4 305 11 6 7.5 4.1 | -0.7 30.7 300 11 6 8.7 4.8  
15000 0.1 32.2 305 10 5 7.3 4.0 | 0.6 33.1 305 10 5 8.7 4.8  
14500 1.2 34.2 305 10 5 8.4 4.6 | 1.9 35.4 305 10 5 8.9 4.9  
14000 2.4 36.3 310 9 5 8.5 4.7 | 3.2 37.8 305 9 5 8.9 4.9  
13500 3.6 38.5 310 9 5 8.9 4.9 | 4.6 40.3 310 9 5 9.3 5.1  
13000 4.9 40.8 310 8 4 9.1 5.0 | 6.0 42.8 310 9 4 9.5 5.2  
12500 6.3 43.3 305 8 4 9.2 5.0 | 7.4 45.3 310 8 4 9.5 5.2  
12000 7.6 45.7 305 8 4 9.2 5.1 | 8.8 47.8 310 8 4 9.6 5.2  
11500 9.0 48.2 305 7 4 9.4 5.1 | 10.2 50.4 310 8 4 9.5 5.2  
11000 10.4 50.7 305 7 4 9.4 5.2 | 11.6 52.9 310 7 4 9.3 5.1  
10500 11.8 53.2 305 7 4 7.0 3.9 | 13.0 55.4 310 7 4 7.9 4.4  
10250 12.2 54.0 305 7 4 7.7 4.2 | 13.6 56.5 310 7 4 8.4 4.6  
10000 13.0 55.4 305 7 4 11.4 6.2 | 14.3 57.7 310 7 4 10.6 5.8  
9750 13.8 56.8 305 7 3 10.6 5.8 | 15.1 59.2 310 7 3 10.0 5.5  
9500 14.6 58.3 305 7 3 10.1 5.5 | 15.8 60.4 310 7 3 10.3 5.6  
9250 15.2 59.4 305 7 3 9.2 5.1 | 16.6 61.9 310 6 3 9.9 5.4  
9000 15.9 60.6 305 7 3 9.9 5.4 | 17.3 63.1 310 6 3 9.0 4.9  
8750 16.6 61.9 305 6 3 10.2 5.6 | 17.9 64.2 305 6 3 8.7 4.7  
8500 17.4 63.3 305 6 3 9.9 5.5 | 18.6 65.5 305 6 3 8.9 4.9  
8250 18.1 64.6 305 6 3 9.6 5.3 | 19.2 66.6 305 6 3 9.1 5.0  
8000 18.8 65.8 305 6 3 10.1 5.5 | 19.9 67.8 305 6 3 9.4 5.2  
7750 19.6 67.3 305 6 3 10.5 5.8 | 20.6 69.1 305 5 3 9.8 5.4  
7500 20.4 68.7 305 6 3 9.8 5.4 | 21.3 70.3 305 5 3 9.6 5.2  
7250 21.1 70.0 305 6 3 9.2 5.1 | 22.0 71.6 305 5 3 9.2 5.1  
7000 21.8 71.2 305 6 3 9.9 5.4 | 22.7 72.9 305 5 3 9.7 5.3  
6750 22.5 72.5 305 6 3 11.1 6.1 | 23.5 74.3 305 5 3 10.8 5.9  
6500 23.4 74.1 305 6 3 10.6 5.8 | 24.3 75.7 305 5 3 10.7 5.9  
6250 24.2 75.6 300 6 3 11.2 6.1 | 25.9 78.6 305 5 2 9.4 5.2  
6000 24.9 76.8 300 6 3 7.6 4.2 | 26.6 79.9 305 5 2 11.1 6.1  
5750 25.5 77.9 305 5 3 14.9 8.2 | 27.7 81.9 305 4 2 20.0 11.0  
5500 27.5 81.5 300 5 3 37.8 20.8 | 29.2 84.6 305 4 2 16.9 9.2  
5250 M M M M M M M | M M M M M M M  
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.  
 
CINH (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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