744  
UXUS97 KGJT 161346  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0746 MDT TUESDAY, JULY 16, 2019  
 
THIS FORECAST IS FOR TUESDAY, JULY 16, 2019:  
 
IF THE TRIGGER TEMPERATURE OF 86.3 F/30.2 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... EXCELLENT  
MAXIMUM RATE OF LIFT........................ 1496 FT/MIN (7.6 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 21199 FT MSL (15783 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 99.0 F/37.7 C  
TIME OF TRIGGER TEMPERATURE.................... 1100 MDT  
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................. 19495 FT MSL (14079 FT AGL)  
THERMAL SOARING OUTLOOK FOR WEDNESDAY 07/17.... EXCELLENT  
 
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.................... 06:01:22 / 20:39:05 MDT  
TOTAL POSSIBLE SUNSHINE........... 14 HR 37 MIN 43 SEC (877 MIN 43 SEC)  
ALTITUDE OF SUN AT 13:20:14 MDT... 71.68 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 07/16/2019 AT 0600 MDT  
 
FREEZING LEVEL.................. 16227 FT MSL (10811 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 16656 FT MSL (11240 FT AGL)  
LIFTED CONDENSATION LEVEL....... 18685 FT MSL (13269 FT AGL)  
LIFTED INDEX.................... -3.4  
K INDEX......................... +22.4  
 
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 -65.6 -86.1 245 15 8 1.5 0.8 M M M M M  
45000 -61.1 -78.0 245 21 11 6.2 3.4 M M M M M  
40000 -50.8 -59.4 245 26 13 8.1 4.4 M M M M M  
38000 -46.0 -50.8 245 27 14 8.1 4.4 M M M M M  
36000 -41.1 -42.0 245 27 14 7.9 4.3 M M M M M  
34000 -36.6 -33.9 245 27 14 7.6 4.2 M M M M M  
32000 -32.0 -25.6 250 26 13 7.7 4.2 M M M M M  
30000 -28.0 -18.4 260 24 13 6.5 3.5 48.0 118.4 8.2 M M  
29000 -26.1 -15.0 260 24 12 6.5 3.5 46.8 116.2 7.4 M M  
28000 -24.1 -11.4 265 23 12 6.7 3.7 45.7 114.2 6.6 M M  
27000 -22.1 -7.8 265 22 11 6.8 3.7 44.4 111.9 5.7 M M  
26000 -19.5 -3.1 265 20 10 6.8 3.7 43.0 109.5 4.7 M M  
25000 -17.5 0.5 265 19 10 6.9 3.8 42.1 107.7 3.9 M M  
24000 -15.4 4.3 265 19 10 6.9 3.8 40.9 105.6 3.0 M M  
23000 -13.3 8.1 260 18 9 6.9 3.8 39.9 103.8 2.2 M M  
22000 -11.3 11.7 260 17 9 5.1 2.8 38.9 102.0 1.4 M M  
21000 -10.1 13.8 255 15 8 4.3 2.4 36.8 98.3 -0.5 1479 7.5  
20000 -9.0 15.8 245 13 7 4.6 2.5 35.0 95.0 -2.2 1414 7.2  
19500 -8.4 16.9 240 12 6 5.3 2.9 34.1 93.5 -3.0 1381 7.0  
19000 -7.4 18.7 235 12 6 8.2 4.5 33.7 92.6 -3.5 1337 6.8  
18500 -6.2 20.8 235 11 6 8.1 4.4 33.4 92.1 -3.9 1288 6.5  
18000 -5.0 23.0 235 11 6 9.1 5.0 33.2 91.7 -4.2 1237 6.3  
17500 -3.7 25.3 235 11 6 9.3 5.1 33.1 91.6 -4.3 1181 6.0  
17000 -2.3 27.9 235 11 6 9.4 5.2 33.0 91.5 -4.4 1125 5.7  
16500 -0.8 30.6 235 11 6 9.8 5.4 33.0 91.4 -4.4 1067 5.4  
16000 0.6 33.1 235 11 6 9.8 5.4 33.0 91.4 -4.5 1008 5.1  
15500 2.1 35.8 240 11 6 9.6 5.3 33.0 91.4 -4.5 950 4.8  
15000 3.5 38.3 240 11 6 9.6 5.3 33.0 91.4 -4.5 892 4.5  
14500 4.9 40.8 240 11 6 9.4 5.2 33.0 91.4 -4.6 834 4.2  
14000 6.3 43.3 240 11 5 9.3 5.1 32.9 91.2 -4.7 778 4.0  
13500 7.7 45.9 245 10 5 9.3 5.1 32.8 91.1 -4.8 721 3.7  
13000 9.1 48.4 245 10 5 9.4 5.1 32.7 90.9 -4.9 665 3.4  
12500 10.5 50.9 245 9 5 9.3 5.1 32.7 90.8 -5.0 608 3.1  
12000 11.8 53.2 245 9 4 8.7 4.8 32.5 90.6 -5.2 554 2.8  
11500 13.1 55.6 250 8 4 8.7 4.8 32.4 90.3 -5.3 500 2.5  
11000 14.2 57.6 250 7 4 7.1 3.9 32.1 89.7 -5.7 452 2.3  
10500 15.3 59.5 250 7 3 10.0 5.5 31.6 89.0 -6.2 406 2.1  
10250 16.1 61.0 245 6 3 10.4 5.7 31.8 89.3 -6.0 372 1.9  
10000 16.7 62.1 245 6 3 6.9 3.8 31.6 89.0 -6.2 349 1.8  
9750 17.2 63.0 240 6 3 7.9 4.3 31.5 88.7 -6.4 325 1.6  
9500 17.8 64.0 240 5 3 7.7 4.2 31.3 88.4 -6.6 301 1.5  
9250 18.3 64.9 235 5 3 7.0 3.8 31.1 88.1 -6.8 277 1.4  
9000 18.8 65.8 230 5 2 6.7 3.7 30.9 87.6 -7.1 256 1.3  
8750 19.3 66.7 220 4 2 7.1 3.9 30.7 87.2 -7.4 234 1.2  
8500 19.8 67.6 210 4 2 6.9 3.8 30.5 86.8 -7.6 212 1.1  
8250 20.7 69.3 195 4 2 5.7 3.2 30.0 86.0 -8.2 168 0.9  
8000 21.1 70.0 185 4 2 4.5 2.5 29.6 85.4 -8.6 150 0.8  
7750 21.4 70.5 175 5 2 4.5 2.5 29.2 84.6 -9.0 133 0.7  
7500 21.7 71.1 170 5 3 4.3 2.4 28.8 83.9 -9.5 117 0.6  
7250 22.0 71.6 165 5 3 3.8 2.1 28.4 83.1 -9.9 100 0.5  
7000 22.2 72.0 160 5 3 2.4 1.3 27.9 82.2 -10.4 86 0.4  
6750 22.3 72.1 150 5 2 1.0 0.5 27.3 81.1 -11.1 76 0.4  
6500 22.3 72.1 145 4 2 0.0 0.0 26.6 79.8 -11.8 68 0.3  
6250 22.3 72.1 140 4 2 0.8 0.4 25.9 78.5 -12.6 61 0.3  
6000 22.3 72.1 130 4 2 -2.7 -1.5 25.1 77.2 -13.4 54 0.3  
5750 21.5 70.7 115 3 1 -20.3 -11.2 23.6 74.5 -14.9 70 0.4  
5500 18.9 66.0 095 2 1 -52.2 -28.7 20.2 68.4 -18.4 142 0.7  
5250 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  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
07/16/2019 AT 0900 MDT | 07/16/2019 AT 1200 MDT  
|  
CAPE... +74.0 LI... -0.2 | CAPE... +99.8 LI... -0.4  
CINH... -79.2 K INDEX... +22.8 | CINH... -4.9 K INDEX... +26.3  
|  
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 -64.8 -84.6 200 38 19 0.9 0.5 | -64.4 -83.9 200 48 25 1.0 0.6  
45000 -61.0 -77.8 205 44 23 5.9 3.2 | -60.7 -77.3 210 44 23 5.7 3.1  
40000 -51.2 -60.2 205 51 26 7.9 4.3 | -51.2 -60.2 205 52 27 7.6 4.2  
38000 -46.5 -51.7 205 52 27 7.9 4.3 | -46.7 -52.1 205 53 27 7.6 4.2  
36000 -41.7 -43.1 205 53 27 7.7 4.3 | -42.1 -43.8 205 53 27 7.5 4.1  
34000 -37.2 -35.0 210 47 24 7.6 4.2 | -37.7 -35.9 210 49 25 7.3 4.0  
32000 -32.6 -26.7 215 41 21 7.7 4.2 | -33.4 -28.1 210 45 23 7.5 4.1  
30000 -28.8 -19.8 230 31 16 6.2 3.4 | -29.3 -20.7 215 37 19 6.8 3.7  
29000 -26.9 -16.4 240 26 13 6.2 3.4 | -27.2 -17.0 220 34 17 6.8 3.7  
28000 -25.0 -13.0 250 23 12 7.0 3.9 | -25.2 -13.4 225 31 16 7.2 3.9  
27000 -22.8 -9.0 250 21 11 7.4 4.0 | -23.0 -9.4 220 31 16 7.3 4.0  
26000 -20.1 -4.2 245 20 10 7.4 4.0 | -20.2 -4.4 215 33 17 7.3 4.0  
25000 -17.8 -0.0 245 19 10 7.2 4.0 | -18.0 -0.4 210 33 17 7.3 4.0  
24000 -15.7 3.7 240 19 10 7.1 3.9 | -15.8 3.6 215 30 15 7.3 4.0  
23000 -13.6 7.5 240 20 10 7.2 3.9 | -13.6 7.5 220 26 14 7.3 4.0  
22000 -11.5 11.3 235 20 11 5.7 3.1 | -11.5 11.3 225 24 12 6.3 3.4  
21000 -9.9 14.2 215 27 14 5.3 2.9 | -9.7 14.5 215 29 15 6.1 3.3  
20000 -8.4 16.9 205 36 19 5.5 3.0 | -8.0 17.6 205 34 18 6.2 3.4  
19500 -7.7 18.1 200 41 21 5.7 3.1 | -7.1 19.2 205 37 19 6.2 3.4  
19000 -6.8 19.8 195 44 23 6.2 3.4 | -6.2 20.8 200 40 21 6.0 3.3  
18500 -6.0 21.2 195 47 24 6.3 3.5 | -5.4 22.3 200 43 22 6.1 3.3  
18000 -5.1 22.8 195 49 25 8.0 4.4 | -4.6 23.7 200 44 23 7.6 4.1  
17500 -3.9 25.0 195 50 26 8.4 4.6 | -3.5 25.7 195 45 23 7.9 4.3  
17000 -2.7 27.1 195 50 26 8.6 4.7 | -2.4 27.7 195 45 23 8.1 4.5  
16500 -1.4 29.5 195 49 25 9.2 5.1 | -1.2 29.8 195 44 23 8.7 4.8  
16000 -0.0 32.0 195 49 25 9.2 5.0 | 0.1 32.2 195 44 22 8.7 4.8  
15500 1.4 34.5 195 48 25 9.7 5.3 | 1.4 34.5 195 43 22 8.8 4.8  
15000 2.8 37.0 195 47 24 9.6 5.3 | 2.7 36.9 195 41 21 8.8 4.8  
14500 4.2 39.6 195 46 24 9.6 5.2 | 4.0 39.2 195 40 21 9.1 5.0  
14000 5.7 42.3 195 44 23 9.5 5.2 | 5.4 41.7 195 39 20 9.2 5.1  
13500 7.1 44.8 195 43 22 9.5 5.2 | 6.8 44.2 195 38 19 9.3 5.1  
13000 8.6 47.5 195 42 22 9.5 5.2 | 8.2 46.8 195 37 19 9.5 5.2  
12500 10.0 50.0 195 41 21 9.4 5.1 | 9.6 49.3 195 36 19 9.5 5.2  
12000 11.4 52.5 190 40 21 8.9 4.9 | 11.1 52.0 195 35 18 9.4 5.2  
11500 12.7 54.9 190 40 20 8.9 4.9 | 12.5 54.5 190 34 18 9.3 5.1  
11000 14.0 57.2 190 41 21 7.8 4.3 | 13.8 56.8 190 34 17 8.5 4.7  
10500 15.2 59.4 190 42 22 4.7 2.6 | 15.0 59.0 190 34 18 10.6 5.8  
10250 15.4 59.7 185 45 23 5.0 2.8 | 16.0 60.8 190 35 18 11.2 6.1  
10000 16.0 60.8 185 48 25 9.5 5.2 | 16.7 62.1 190 36 18 8.9 4.9  
9750 16.6 61.9 185 51 26 8.4 4.6 | 17.4 63.3 190 37 19 9.5 5.2  
9500 17.3 63.1 185 54 28 8.3 4.6 | 18.1 64.6 190 38 20 9.3 5.1  
9250 17.8 64.0 185 57 30 6.6 3.6 | 18.7 65.7 185 40 21 9.2 5.1  
9000 18.3 64.9 185 60 31 7.0 3.8 | 19.4 66.9 185 43 22 9.4 5.1  
8750 18.8 65.8 185 62 32 8.2 4.5 | 20.8 69.4 185 48 25 9.4 5.2  
8500 19.4 66.9 180 64 33 7.5 4.1 | 21.5 70.7 185 50 26 9.1 5.0  
8250 20.2 68.4 180 64 33 5.7 3.1 | 22.1 71.8 185 51 26 9.7 5.3  
8000 20.7 69.3 180 63 33 7.4 4.1 | 22.9 73.2 185 52 27 10.5 5.8  
7750 21.2 70.2 180 62 32 6.2 3.4 | 23.7 74.7 185 52 27 9.9 5.4  
7500 21.6 70.9 180 60 31 4.1 2.2 | 24.4 75.9 185 52 27 9.0 4.9  
7250 21.9 71.4 180 58 30 4.5 2.5 | 25.0 77.0 185 52 27 9.4 5.2  
7000 22.3 72.1 180 57 29 7.3 4.0 | 25.8 78.4 185 52 27 10.9 6.0  
6750 22.8 73.0 180 56 29 8.2 4.5 | 26.6 79.9 185 52 27 11.2 6.2  
6500 23.4 74.1 180 54 28 7.8 4.3 | 27.5 81.5 185 52 27 11.2 6.2  
6250 23.9 75.0 180 53 27 7.4 4.0 | 28.3 82.9 185 51 26 10.5 5.8  
6000 24.5 76.1 180 51 26 9.9 5.4 | 29.1 84.4 185 51 26 10.8 5.9  
5750 25.5 77.9 180 50 26 18.0 9.9 | 30.1 86.2 185 51 26 20.5 11.3  
5500 27.0 80.6 180 48 25 18.7 10.3 | 32.5 90.5 185 47 24 48.7 26.7  
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  
 
07/16/2019 AT 1500 MDT | 07/16/2019 AT 1800 MDT  
|  
CAPE... +164.3 LI... -0.8 | CAPE... +202.7 LI... -0.7  
CINH... -15.6 K INDEX... +27.4 | CINH... -31.0 K INDEX... +26.6  
|  
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 -64.5 -84.1 200 47 24 0.9 0.5 | -64.5 -84.1 205 44 23 0.8 0.4  
45000 -60.3 -76.5 215 42 22 5.9 3.3 | -61.0 -77.8 210 47 24 5.9 3.2  
40000 -51.1 -60.0 210 50 26 7.1 3.9 | -51.4 -60.5 205 54 28 7.1 3.9  
38000 -46.9 -52.4 205 53 27 7.1 3.9 | -47.1 -52.8 205 55 28 7.1 3.9  
36000 -42.6 -44.7 205 55 28 7.1 3.9 | -42.9 -45.2 205 56 29 7.1 3.9  
34000 -38.3 -36.9 205 53 27 7.2 3.9 | -38.5 -37.3 205 54 28 7.2 4.0  
32000 -34.0 -29.2 205 50 26 7.3 4.0 | -34.2 -29.6 205 52 27 7.1 3.9  
30000 -29.7 -21.5 210 43 22 7.2 3.9 | -29.7 -21.5 205 47 24 7.5 4.1  
29000 -27.5 -17.5 210 40 20 7.2 3.9 | -27.5 -17.5 205 44 23 7.5 4.1  
28000 -25.4 -13.7 215 36 19 7.4 4.0 | -25.3 -13.5 205 42 21 7.5 4.1  
27000 -22.6 -8.7 215 34 17 7.4 4.1 | -23.0 -9.4 205 41 21 7.5 4.1  
26000 -20.4 -4.7 215 32 17 7.4 4.1 | -20.2 -4.4 205 40 21 7.5 4.1  
25000 -18.1 -0.6 215 31 16 7.6 4.2 | -17.9 -0.2 205 40 21 7.5 4.1  
24000 -15.9 3.4 215 32 16 7.7 4.2 | -15.7 3.7 200 42 22 7.5 4.1  
23000 -13.6 7.5 210 34 17 7.7 4.2 | -13.5 7.7 200 44 23 7.5 4.1  
22000 -11.3 11.7 205 36 18 6.5 3.5 | -11.3 11.7 195 46 24 6.8 3.8  
21000 -9.5 14.9 200 40 21 6.3 3.5 | -9.3 15.3 195 46 24 6.8 3.7  
20000 -7.8 18.0 195 45 23 6.6 3.6 | -7.4 18.7 195 47 24 7.0 3.9  
19500 -6.9 19.6 195 47 24 6.9 3.8 | -6.4 20.5 195 47 24 7.4 4.1  
19000 -5.8 21.6 195 49 25 7.5 4.1 | -5.3 22.5 195 48 25 8.2 4.5  
18500 -4.8 23.4 190 51 26 7.5 4.1 | -4.1 24.6 190 49 25 8.2 4.5  
18000 -3.7 25.3 190 52 27 8.2 4.5 | -3.0 26.6 190 50 26 8.3 4.5  
17500 -2.5 27.5 190 53 27 8.3 4.5 | -1.8 28.8 190 51 26 8.3 4.6  
17000 -1.3 29.7 190 53 27 8.4 4.6 | -0.6 30.9 190 52 27 8.5 4.7  
16500 -0.1 31.8 190 54 28 8.7 4.8 | 0.7 33.3 190 52 27 9.1 5.0  
16000 1.2 34.2 190 55 28 8.7 4.7 | 2.1 35.8 190 52 27 9.0 4.9  
15500 2.5 36.5 190 55 28 9.4 5.2 | 3.4 38.1 190 52 27 9.5 5.2  
15000 3.9 39.0 190 56 29 9.4 5.2 | 4.8 40.6 190 53 27 9.4 5.2  
14500 5.3 41.5 190 56 29 9.4 5.1 | 6.2 43.2 190 53 28 9.5 5.2  
14000 6.7 44.1 190 56 29 9.3 5.1 | 7.7 45.9 190 54 28 9.5 5.2  
13500 8.1 46.6 185 57 29 9.4 5.2 | 9.1 48.4 190 55 28 9.5 5.2  
13000 9.6 49.3 185 56 29 9.5 5.2 | 10.5 50.9 190 55 28 9.6 5.3  
12500 11.0 51.8 185 56 29 9.5 5.2 | 11.9 53.4 190 56 29 9.6 5.3  
12000 12.4 54.3 185 54 28 9.5 5.2 | 13.4 56.1 190 56 29 9.5 5.2  
11500 13.8 56.8 185 53 27 9.5 5.2 | 14.8 58.6 185 57 29 9.6 5.3  
11000 15.2 59.4 190 49 25 8.5 4.6 | 16.1 61.0 185 57 30 7.9 4.3  
10500 16.4 61.5 190 44 23 10.7 5.9 | 17.2 63.0 185 59 30 11.9 6.5  
10250 17.3 63.1 190 41 21 11.5 6.3 | 18.3 64.9 185 59 30 12.8 7.0  
10000 18.1 64.6 190 37 19 9.0 5.0 | 19.0 66.2 185 60 31 8.2 4.5  
9750 18.8 65.8 190 33 17 9.7 5.3 | 19.7 67.5 185 61 31 9.4 5.2  
9500 19.5 67.1 190 28 15 9.4 5.2 | 20.4 68.7 185 62 32 9.3 5.1  
9250 20.2 68.4 195 25 13 9.6 5.3 | 21.0 69.8 185 63 32 7.9 4.3  
9000 21.7 71.1 195 23 12 10.1 5.5 | 21.6 70.9 185 63 32 8.6 4.7  
8750 22.4 72.3 195 22 11 10.0 5.5 | 22.4 72.3 185 63 32 10.4 5.7  
8500 23.2 73.8 195 21 11 9.3 5.1 | 23.1 73.6 185 63 32 10.0 5.5  
8250 23.9 75.0 195 20 10 9.7 5.3 | 24.5 76.1 185 62 32 9.5 5.2  
8000 24.6 76.3 195 20 10 10.6 5.8 | 25.3 77.5 185 62 32 10.4 5.7  
7750 25.4 77.7 195 19 10 10.2 5.6 | 26.0 78.8 185 62 32 10.1 5.5  
7500 26.2 79.2 200 19 10 9.2 5.1 | 26.7 80.1 185 62 32 8.9 4.9  
7250 26.8 80.2 200 18 9 9.4 5.2 | 27.4 81.3 185 62 32 8.9 4.9  
7000 27.6 81.7 200 18 9 10.9 6.0 | 28.1 82.6 185 62 32 10.4 5.7  
6750 28.4 83.1 200 17 9 10.7 5.9 | 28.9 84.0 185 62 32 10.7 5.9  
6500 29.2 84.6 200 17 9 9.9 5.4 | 29.7 85.5 185 61 32 10.5 5.7  
6250 29.9 85.8 200 17 9 9.9 5.4 | 30.5 86.9 185 61 31 10.9 6.0  
6000 30.6 87.1 200 16 8 9.5 5.2 | 31.2 88.2 185 61 31 7.7 4.2  
5750 31.6 88.9 200 16 8 19.2 10.5 | 31.7 89.1 185 61 31 9.4 5.2  
5500 34.5 94.1 205 13 7 71.9 39.4 | 33.8 92.8 185 56 29 59.7 32.8  
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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