340  
UXUS97 KGJT 181330  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0630 MST TUESDAY, DECEMBER 18, 2018  
 
THIS FORECAST IS FOR TUESDAY, DECEMBER 18, 2018:  
 
IF THE TRIGGER TEMPERATURE OF 51.0 F/10.5 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... POOR  
MAXIMUM RATE OF LIFT........................ 166 FT/MIN (0.8 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 6929 FT MSL (2090 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....... NONE  
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS  
HEIGHT OF THE -3 THERMAL INDEX................. 6118 FT MSL (1279 FT AGL)  
THERMAL SOARING OUTLOOK FOR WEDNESDAY 12/19.... POOR  
 
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.................... 07:28:17 / 16:53:27 MST  
TOTAL POSSIBLE SUNSHINE........... 9 HR 25 MIN 10 SEC (565 MIN 10 SEC)  
ALTITUDE OF SUN AT 12:10:52 MST... 27.43 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 12/18/2018 AT 0500 MST  
 
FREEZING LEVEL.................. 6543 FT MSL (1704 FT AGL)  
ADDITIONAL FREEZING LEVEL....... 6626 FT MSL (1787 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 16307 FT MSL (11468 FT AGL)  
LIFTED CONDENSATION LEVEL....... 10512 FT MSL (5673 FT AGL)  
LIFTED INDEX.................... +13.0  
K INDEX......................... +9.3  
 
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 -59.7 -75.5 330 14 7 1.1 0.6 102.5 216.5 54.8 M M  
45000 -57.3 -71.1 340 48 25 -0.5 -0.3 81.6 178.9 45.9 M M  
40000 -55.0 -67.0 335 39 20 -1.6 -0.9 62.1 143.8 36.4 M M  
38000 -55.4 -67.7 310 22 11 3.7 2.1 51.6 124.8 30.5 M M  
36000 -53.6 -64.5 315 17 9 4.8 2.6 45.5 113.9 27.1 M M  
34000 -51.8 -61.2 265 14 7 3.6 2.0 39.6 103.3 23.7 M M  
32000 -48.8 -55.8 210 27 14 8.3 4.6 35.6 96.1 21.4 M M  
30000 -44.0 -47.2 205 37 19 6.6 3.6 34.3 93.7 21.0 M M  
29000 -41.7 -43.1 215 31 16 7.9 4.3 33.3 91.9 20.5 M M  
28000 -39.4 -38.9 225 27 14 7.9 4.4 32.6 90.7 20.2 M M  
27000 -37.2 -35.0 245 24 12 7.1 3.9 31.7 89.1 19.8 M M  
26000 -35.0 -31.0 245 22 11 7.1 3.9 30.7 87.2 19.2 M M  
25000 -32.6 -26.7 245 20 10 8.8 4.9 30.1 86.1 19.0 M M  
24000 -30.7 -23.3 265 20 10 7.7 4.2 28.8 83.9 18.2 M M  
23000 -28.1 -18.6 280 17 9 5.5 3.0 28.5 83.3 18.1 M M  
22000 -26.1 -15.0 295 14 7 7.8 4.3 27.3 81.1 17.3 M M  
21000 -23.5 -10.3 305 16 8 8.6 4.7 26.8 80.2 17.2 M M  
20000 -20.3 -4.5 310 18 9 8.4 4.6 26.3 79.3 17.0 M M  
19500 -19.1 -2.4 310 17 9 8.4 4.6 26.0 78.9 16.9 M M  
19000 -18.0 -0.4 305 16 8 4.5 2.5 25.7 78.2 16.6 M M  
18500 -17.8 -0.0 305 15 8 2.8 1.5 24.3 75.7 15.5 M M  
18000 -17.2 1.0 305 15 8 4.3 2.3 23.3 73.9 14.7 M M  
17500 -16.2 2.8 305 15 8 8.2 4.5 22.7 72.9 14.2 M M  
17000 -15.0 5.0 305 16 8 7.9 4.3 22.4 72.2 14.0 M M  
16500 -13.9 7.0 305 16 8 7.7 4.2 22.0 71.7 13.8 M M  
16000 -12.7 9.1 305 16 8 5.3 2.9 21.8 71.2 13.6 M M  
15500 -12.7 9.1 300 16 8 0.1 0.1 20.1 68.3 12.2 M M  
15000 -12.0 10.4 295 16 8 6.6 3.6 19.2 66.6 11.5 M M  
14500 -11.1 12.0 295 16 8 6.5 3.5 18.7 65.6 11.0 M M  
14000 -10.4 13.3 290 16 8 -1.1 -0.6 17.8 64.1 10.3 M M  
13500 -11.1 12.0 295 16 8 -5.2 -2.8 15.5 59.9 8.2 M M  
13000 -11.1 12.0 300 15 8 7.3 4.0 13.9 57.1 6.8 M M  
12500 -10.0 14.0 305 15 8 7.3 4.0 13.5 56.4 6.4 M M  
12000 -8.9 16.0 310 15 8 7.3 4.0 13.2 55.7 6.1 M M  
11500 -7.8 18.0 315 13 6 7.3 4.0 12.7 54.9 5.8 M M  
11000 -6.7 19.9 320 10 5 7.3 4.0 12.3 54.2 5.4 M M  
10500 -5.6 21.9 335 8 4 7.3 4.0 12.0 53.5 5.1 M M  
10250 -5.0 23.0 340 7 4 7.4 4.1 11.8 53.2 4.9 M M  
10000 -4.5 23.9 345 7 4 7.9 4.3 11.6 52.9 4.8 M M  
9750 -3.9 25.0 350 7 4 8.1 4.5 11.5 52.6 4.7 M M  
9500 -3.3 26.1 350 8 4 8.1 4.4 11.3 52.4 4.6 M M  
9250 -2.7 27.1 355 8 4 8.1 4.5 11.2 52.2 4.4 M M  
9000 -2.1 28.2 355 8 4 8.0 4.4 11.1 52.0 4.3 M M  
8750 -1.5 29.3 350 7 4 8.5 4.7 11.0 51.7 4.2 M M  
8500 -0.9 30.4 340 7 4 6.5 3.6 10.8 51.5 4.1 M M  
8250 -0.6 30.9 330 7 4 -0.4 -0.2 10.3 50.6 3.6 M M  
8000 -0.9 30.4 315 7 4 -5.5 -3.0 9.3 48.7 2.6 M M  
7750 -1.1 30.0 315 6 3 1.8 1.0 8.3 46.9 1.7 M M  
7500 -0.6 30.9 315 6 3 9.3 5.1 8.1 46.5 1.5 M M  
7250 -0.0 32.0 310 5 3 2.8 1.5 7.9 46.1 1.3 M M  
7000 -0.2 31.6 310 4 2 -4.0 -2.2 7.0 44.6 0.4 M M  
6750 -0.3 31.5 315 4 2 4.5 2.5 6.1 43.0 -0.4 164 0.8  
6500 0.1 32.2 315 3 2 -4.8 -2.6 5.7 42.3 -0.8 147 0.7  
6250 -0.8 30.6 325 3 1 -8.0 -4.4 4.1 39.3 -2.4 167 0.8  
6000 -0.8 30.6 330 2 1 3.6 2.0 3.4 38.1 -3.1 158 0.8  
5750 -0.7 30.7 330 2 1 2.1 1.2 2.8 37.0 -3.7 147 0.7  
5500 -0.5 31.1 320 1 1 -0.9 -0.5 2.2 36.0 -4.4 135 0.7  
5250 -0.8 30.6 305 1 1 -5.0 -2.7 1.1 34.1 -5.4 137 0.7  
5000 -1.2 29.8 280 1 1 -7.2 -4.0 0.0 32.0 -6.5 142 0.7  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
12/18/2018 AT 0800 MST | 12/18/2018 AT 1100 MST  
|  
CAPE... 0.0 LI... +6.6 | CAPE... 0.0 LI... +8.3  
CINH... -0.2 K INDEX... +8.3 | CINH... -0.1 K INDEX... +1.8  
|  
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 -59.4 -74.9 335 19 10 1.1 0.6 | -60.3 -76.5 335 21 11 1.8 1.0  
45000 -57.8 -72.0 340 27 14 2.0 1.1 | -57.4 -71.3 335 29 15 2.4 1.3  
40000 -54.0 -65.2 335 27 14 2.4 1.3 | -53.9 -65.0 335 33 17 2.3 1.3  
38000 -52.8 -63.0 335 25 13 1.5 0.8 | -52.4 -62.3 335 31 16 2.6 1.4  
36000 -51.9 -61.4 335 20 10 1.5 0.8 | -50.9 -59.6 330 27 14 2.6 1.4  
34000 -50.5 -58.9 340 16 8 5.6 3.1 | -49.2 -56.6 330 24 12 3.7 2.0  
32000 -47.2 -53.0 330 13 6 5.5 3.0 | -46.8 -52.2 330 22 11 3.6 2.0  
30000 -43.5 -46.3 320 10 5 7.8 4.3 | -43.9 -47.0 335 21 11 8.0 4.4  
29000 -41.2 -42.2 325 11 6 7.8 4.3 | -41.4 -42.5 335 20 10 8.1 4.4  
28000 -38.9 -38.0 325 11 6 7.8 4.3 | -39.0 -38.2 335 20 10 8.1 4.4  
27000 -36.5 -33.7 325 12 6 7.7 4.2 | -36.6 -33.9 335 20 10 8.6 4.7  
26000 -34.2 -29.6 325 12 6 7.5 4.1 | -33.9 -29.0 335 19 10 8.8 4.8  
25000 -32.0 -25.6 320 12 6 7.5 4.1 | -31.3 -24.3 335 18 9 8.8 4.8  
24000 -29.7 -21.5 320 12 6 7.5 4.1 | -28.7 -19.7 335 17 9 8.6 4.7  
23000 -27.6 -17.7 320 11 6 6.9 3.8 | -26.2 -15.2 340 17 9 8.4 4.6  
22000 -25.0 -13.0 320 11 5 6.9 3.8 | -23.7 -10.7 340 16 8 8.4 4.6  
21000 -22.9 -9.2 315 10 5 7.4 4.1 | -21.2 -6.2 340 15 8 7.1 3.9  
20000 -20.7 -5.3 315 10 5 7.4 4.1 | -19.2 -2.6 340 14 7 6.7 3.7  
19500 -19.6 -3.3 315 10 5 7.4 4.1 | -18.2 -0.8 340 13 7 6.7 3.7  
19000 -18.5 -1.3 315 10 5 7.5 4.1 | -16.7 1.9 340 12 6 6.9 3.8  
18500 -17.4 0.7 315 10 5 6.8 3.8 | -15.8 3.6 335 11 6 5.0 2.8  
18000 -16.4 2.5 315 9 5 6.7 3.7 | -15.0 5.0 330 11 5 5.2 2.8  
17500 -15.4 4.3 315 9 5 6.5 3.5 | -14.3 6.3 330 10 5 5.0 2.7  
17000 -14.5 5.9 315 9 5 5.7 3.1 | -13.6 7.5 325 10 5 4.8 2.6  
16500 -13.7 7.3 315 9 4 5.7 3.1 | -12.9 8.8 320 9 5 4.8 2.7  
16000 -12.9 8.8 315 8 4 5.6 3.1 | -12.2 10.0 320 9 5 4.8 2.6  
15500 -12.1 10.2 315 8 4 5.7 3.1 | -11.5 11.3 320 9 4 4.8 2.7  
15000 -11.3 11.7 315 8 4 4.7 2.6 | -10.8 12.6 315 8 4 4.7 2.6  
14500 -10.6 12.9 315 8 4 4.5 2.5 | -10.1 13.8 315 8 4 4.8 2.6  
14000 -10.0 14.0 315 8 4 3.8 2.1 | -9.4 15.1 315 8 4 4.1 2.3  
13500 -9.5 14.9 310 7 4 3.4 1.8 | -8.9 16.0 315 8 4 4.0 2.2  
13000 -9.0 15.8 310 7 4 3.3 1.8 | -8.3 17.1 315 8 4 3.7 2.0  
12500 -8.6 16.5 310 6 3 3.3 1.8 | -7.8 18.0 315 8 4 3.5 1.9  
12000 -8.1 17.4 310 6 3 3.8 2.1 | -7.4 18.7 315 7 4 3.0 1.6  
11500 -7.5 18.5 315 5 3 4.5 2.5 | -7.0 19.4 315 6 3 2.7 1.5  
11000 -6.8 19.8 315 5 2 5.2 2.8 | -6.6 20.1 315 6 3 4.3 2.3  
10500 -6.0 21.2 320 4 2 5.9 3.3 | -5.8 21.6 315 5 2 5.4 3.0  
10250 -5.5 22.1 320 4 2 5.7 3.1 | -5.4 22.3 315 4 2 4.9 2.7  
10000 -5.1 22.8 320 4 2 5.7 3.1 | -5.1 22.8 315 4 2 5.1 2.8  
9750 -4.7 23.5 325 3 2 7.0 3.8 | -4.7 23.5 315 4 2 6.8 3.7  
9500 -4.1 24.6 325 3 2 7.8 4.3 | -4.1 24.6 315 3 2 7.1 3.9  
9250 -3.5 25.7 325 3 2 7.4 4.1 | -3.6 25.5 315 3 1 7.1 3.9  
9000 -3.0 26.6 330 3 1 7.1 3.9 | -3.1 26.4 315 3 1 7.2 3.9  
8750 -2.5 27.5 330 3 1 6.4 3.5 | -2.6 27.3 315 2 1 6.5 3.5  
8500 -2.0 28.4 335 2 1 6.4 3.5 | -2.1 28.2 315 2 1 6.1 3.3  
8250 -1.5 29.3 340 2 1 5.5 3.0 | -1.7 28.9 320 2 1 5.9 3.2  
8000 -1.2 29.8 340 2 1 4.3 2.4 | -1.2 29.8 320 2 1 5.5 3.0  
7750 -0.8 30.6 345 2 1 5.1 2.8 | -0.8 30.6 325 2 1 6.1 3.4  
7500 -0.4 31.3 345 1 1 5.4 3.0 | -0.3 31.5 325 1 1 5.9 3.2  
7250 -0.0 32.0 345 1 1 4.9 2.7 | 0.1 32.2 325 1 1 4.9 2.7  
7000 0.3 32.5 340 1 0 4.6 2.5 | 0.4 32.7 325 1 1 3.8 2.1  
6750 0.7 33.3 335 1 0 5.3 2.9 | 0.7 33.3 320 1 0 7.0 3.8  
6500 1.1 34.0 000 0 0 4.8 2.6 | 1.4 34.5 315 1 0 8.5 4.6  
6250 1.4 34.5 000 0 0 3.1 1.7 | 1.9 35.4 315 1 0 6.7 3.7  
6000 1.7 35.1 000 0 0 5.6 3.1 | 2.4 36.3 000 0 0 6.7 3.7  
5750 2.0 35.6 000 0 0 -2.9 -1.6 | 3.0 37.4 000 0 0 8.5 4.6  
5500 0.9 33.6 075 1 0 -26.8 -14.7 | 3.8 38.8 000 0 0 14.1 7.7  
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  
 
12/18/2018 AT 1400 MST | 12/18/2018 AT 1700 MST  
|  
CAPE... 0.0 LI... +8.0 | CAPE... 0.0 LI... +7.0  
CINH... -0.1 K INDEX... -4.3 | CINH... -0.0 K INDEX... +9.1  
|  
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 -60.2 -76.4 335 24 12 2.4 1.3 | -61.2 -78.2 355 113 58 3.5 1.9  
45000 -56.4 -69.5 330 31 16 2.8 1.5 | -56.0 -68.8 350 113 58 2.3 1.3  
40000 -52.2 -62.0 330 39 20 2.8 1.5 | -52.4 -62.3 345 121 62 2.4 1.3  
38000 -51.0 -59.8 330 39 20 1.6 0.9 | -51.1 -60.0 345 123 64 2.2 1.2  
36000 -50.0 -58.0 325 38 19 1.6 0.9 | -49.6 -57.3 350 125 64 2.2 1.2  
34000 -48.6 -55.5 325 35 18 3.7 2.0 | -47.7 -53.9 350 125 65 5.2 2.8  
32000 -46.3 -51.3 320 30 15 3.7 2.0 | -44.6 -48.3 350 124 64 5.2 2.9  
30000 -43.5 -46.3 315 25 13 7.3 4.0 | -41.2 -42.2 350 121 62 6.8 3.7  
29000 -41.3 -42.3 315 23 12 7.4 4.1 | -39.2 -38.6 350 118 61 6.8 3.7  
28000 -39.1 -38.4 315 22 11 7.4 4.1 | -37.1 -34.8 350 114 59 6.8 3.7  
27000 -36.8 -34.2 315 20 10 8.4 4.6 | -35.1 -31.2 350 110 57 6.7 3.7  
26000 -34.2 -29.6 315 20 10 8.9 4.9 | -33.1 -27.6 350 104 54 6.6 3.6  
25000 -31.5 -24.7 315 19 10 8.9 4.9 | -31.1 -24.0 350 98 51 6.6 3.6  
24000 -28.9 -20.0 315 19 10 8.6 4.7 | -29.1 -20.4 350 92 48 6.9 3.8  
23000 -26.5 -15.7 315 18 9 8.0 4.4 | -26.9 -16.4 350 89 46 7.6 4.1  
22000 -24.1 -11.4 315 17 9 8.0 4.4 | -24.7 -12.5 350 85 44 7.6 4.2  
21000 -21.8 -7.2 315 16 8 7.3 4.0 | -22.5 -8.5 350 82 42 7.0 3.9  
20000 -19.7 -3.5 315 15 8 7.1 3.9 | -20.0 -4.0 350 83 43 6.7 3.7  
19500 -18.1 -0.6 315 14 7 7.1 3.9 | -19.0 -2.2 350 84 43 6.7 3.7  
19000 -17.0 1.4 315 14 7 7.1 3.9 | -18.0 -0.4 350 84 43 6.7 3.7  
18500 -15.9 3.4 315 13 7 7.1 3.9 | -17.0 1.4 350 84 43 7.3 4.0  
18000 -14.9 5.2 315 13 7 7.1 3.9 | -15.9 3.4 350 84 43 7.2 4.0  
17500 -13.8 7.2 315 12 6 6.7 3.7 | -14.8 5.4 350 83 43 6.7 3.7  
17000 -12.8 9.0 315 12 6 6.2 3.4 | -13.9 7.0 350 82 42 6.2 3.4  
16500 -11.9 10.6 315 12 6 6.2 3.4 | -13.0 8.6 350 82 42 6.1 3.4  
16000 -11.1 12.0 315 12 6 4.7 2.6 | -12.1 10.2 350 82 42 5.7 3.1  
15500 -10.4 13.3 315 11 6 4.9 2.7 | -11.3 11.7 350 83 42 5.8 3.2  
15000 -9.7 14.5 315 11 6 3.9 2.2 | -10.5 13.1 350 84 43 4.9 2.7  
14500 -9.1 15.6 315 11 6 3.9 2.1 | -9.8 14.4 355 85 44 4.8 2.6  
14000 -8.6 16.5 315 10 5 3.6 2.0 | -9.1 15.6 355 86 44 4.5 2.5  
13500 -8.1 17.4 315 10 5 3.5 1.9 | -8.4 16.9 355 87 45 4.4 2.4  
13000 -7.6 18.3 315 9 5 3.6 2.0 | -7.7 18.1 355 88 45 4.3 2.4  
12500 -7.1 19.2 310 9 5 3.6 2.0 | -7.1 19.2 355 88 45 4.2 2.3  
12000 -6.6 20.1 310 8 4 3.6 2.0 | -6.5 20.3 355 87 45 4.4 2.4  
11500 -6.1 21.0 310 7 4 3.6 2.0 | -5.8 21.6 355 85 44 4.6 2.5  
11000 -5.6 21.9 305 7 3 3.9 2.1 | -5.1 22.8 355 84 43 4.7 2.6  
10500 -5.0 23.0 305 5 3 4.2 2.3 | -4.4 24.1 355 80 41 4.7 2.6  
10250 -4.7 23.5 305 5 2 3.8 2.1 | -4.1 24.6 355 79 40 4.9 2.7  
10000 -4.4 24.1 300 4 2 4.4 2.4 | -3.7 25.3 355 76 39 5.3 2.9  
9750 -4.1 24.6 300 4 2 6.1 3.3 | -3.3 26.1 355 74 38 5.3 2.9  
9500 -3.6 25.5 300 3 2 6.1 3.4 | -2.9 26.8 355 71 37 4.9 2.7  
9250 -3.2 26.2 300 3 2 6.4 3.5 | -2.6 27.3 355 69 35 5.7 3.1  
9000 -2.7 27.1 295 3 1 7.1 3.9 | -2.1 28.2 355 65 33 7.2 3.9  
8750 -2.1 28.2 295 2 1 6.8 3.7 | -1.6 29.1 355 60 31 6.6 3.6  
8500 -1.7 28.9 290 2 1 6.5 3.6 | -1.1 30.0 355 56 29 5.8 3.2  
8250 -1.2 29.8 285 2 1 6.4 3.5 | -0.7 30.7 355 52 27 6.3 3.5  
8000 -0.7 30.7 285 2 1 6.0 3.3 | -0.2 31.6 355 51 26 6.5 3.6  
7750 -0.2 31.6 285 2 1 7.4 4.1 | 0.3 32.5 355 50 26 6.8 3.8  
7500 0.4 32.7 280 2 1 8.1 4.5 | 0.8 33.4 355 42 21 7.1 3.9  
7250 0.9 33.6 280 1 1 6.8 3.7 | 1.3 34.3 355 38 20 6.4 3.5  
7000 1.4 34.5 285 1 1 6.0 3.3 | 1.8 35.2 355 42 22 6.4 3.5  
6750 1.9 35.4 290 1 1 7.5 4.1 | 2.2 36.0 355 45 23 5.8 3.2  
6500 2.5 36.5 290 1 1 9.7 5.3 | 2.7 36.9 355 32 17 6.8 3.7  
6250 3.3 37.9 295 1 1 10.0 5.5 | 3.2 37.8 360 60 31 7.5 4.1  
6000 4.0 39.2 300 1 1 9.7 5.3 | 3.8 38.8 360 87 45 9.1 5.0  
5750 4.7 40.5 305 1 1 10.3 5.7 | 4.4 39.9 360 114 59 2.0 1.1  
5500 5.6 42.1 295 1 0 13.3 7.3 | 3.0 37.4 360 10 5 10.6 5.8  
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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