576  
UXUS97 KGJT 311246  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0646 MDT SUNDAY, MAY 31, 2020  
 
THIS FORECAST IS FOR SUNDAY, MAY 31, 2020:  
 
IF THE TRIGGER TEMPERATURE OF 78.9 F/26.0 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... EXCELLENT  
MAXIMUM RATE OF LIFT........................ 996 FT/MIN (5.1 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 18113 FT MSL (13274 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 90.0 F/32.7 C  
TIME OF TRIGGER TEMPERATURE.................... 1000 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................. 11754 FT MSL (6915 FT AGL)  
THERMAL SOARING OUTLOOK FOR MONDAY 06/01....... 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.................... 05:50:05 / 20:33:48 MDT  
TOTAL POSSIBLE SUNSHINE........... 14 HR 43 MIN 43 SEC (883 MIN 43 SEC)  
ALTITUDE OF SUN AT 13:11:57 MDT... 72.75 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 05/31/2020 AT 0600 MDT  
 
FREEZING LEVEL.................. 14995 FT MSL (10156 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 15039 FT MSL (10200 FT AGL)  
LIFTED CONDENSATION LEVEL....... 15844 FT MSL (11005 FT AGL)  
LIFTED INDEX.................... -2.5  
K INDEX......................... +24.0  
 
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 -65.4 -85.7 185 21 11 -2.3 -1.3 87.9 190.1 32.0 M M  
45000 -64.5 -84.1 215 46 24 -6.1 -3.3 64.8 148.7 20.1 M M  
40000 -58.7 -73.7 205 49 25 8.9 4.9 49.7 121.4 11.6 M M  
38000 -53.4 -64.1 205 46 24 8.9 4.9 48.9 120.0 11.4 M M  
36000 -48.1 -54.6 210 44 23 9.0 4.9 48.2 118.8 11.2 M M  
34000 -42.9 -45.2 205 44 23 8.2 4.5 47.4 117.3 10.9 M M  
32000 -37.9 -36.2 200 44 23 8.1 4.4 46.2 115.2 10.3 M M  
30000 -32.6 -26.7 210 44 23 9.2 5.0 44.4 112.0 9.2 M M  
29000 -30.5 -22.9 215 44 23 6.0 3.3 43.4 110.1 8.5 M M  
28000 -28.2 -18.8 220 44 22 8.4 4.6 42.6 108.8 8.0 M M  
27000 -25.7 -14.3 220 39 20 9.3 5.1 42.1 107.8 7.7 M M  
26000 -23.1 -9.6 215 35 18 8.4 4.6 41.7 107.0 7.5 M M  
25000 -20.5 -4.9 215 31 16 8.7 4.8 41.2 106.2 7.2 M M  
24000 -18.2 -0.8 210 25 13 8.2 4.5 40.6 105.1 6.7 M M  
23000 -16.4 2.5 215 23 12 5.6 3.1 39.2 102.6 5.6 M M  
22000 -14.6 5.7 225 22 11 6.9 3.8 37.9 100.2 4.6 M M  
21000 -12.5 9.5 230 24 13 6.8 3.7 37.0 98.5 3.8 M M  
20000 -10.8 12.6 235 27 14 1.4 0.8 35.6 96.0 2.6 M M  
19500 -10.1 13.8 240 29 15 7.2 3.9 34.7 94.5 1.8 M M  
19000 -9.2 15.4 235 31 16 7.2 4.0 34.2 93.6 1.4 M M  
18500 -8.1 17.4 235 31 16 8.3 4.6 33.8 92.8 1.0 M M  
18000 -7.6 18.3 240 30 15 1.8 1.0 32.7 90.9 -0.0 1196 6.1  
17500 -6.5 20.3 245 28 15 9.8 5.4 32.4 90.3 -0.4 1147 5.8  
17000 -5.1 22.8 245 27 14 8.9 4.9 32.4 90.3 -0.4 1090 5.5  
16500 -3.5 25.7 250 26 13 7.4 4.1 31.8 89.3 -1.0 1018 5.2  
16000 -2.4 27.7 255 25 13 7.6 4.2 31.5 88.6 -1.4 972 4.9  
15500 -1.1 30.0 255 23 12 9.3 5.1 31.3 88.3 -1.6 919 4.7  
15000 0.2 32.4 255 22 11 9.2 5.0 31.2 88.1 -1.7 863 4.4  
14500 1.6 34.9 250 20 10 9.2 5.0 31.1 87.9 -1.8 808 4.1  
14000 3.0 37.4 250 19 10 9.1 5.0 31.0 87.8 -1.8 752 3.8  
13500 4.3 39.7 245 16 8 8.6 4.7 30.9 87.6 -1.9 696 3.5  
13000 5.5 41.9 235 14 7 7.9 4.4 30.6 87.1 -2.3 647 3.3  
12500 6.6 43.9 225 12 6 7.9 4.3 30.3 86.6 -2.6 597 3.0  
12000 7.8 46.0 215 11 6 7.9 4.3 30.0 86.1 -2.9 548 2.8  
11500 9.0 48.2 215 13 6 7.9 4.3 29.7 85.5 -3.2 499 2.5  
11000 10.1 50.2 215 14 7 7.6 4.2 29.4 85.0 -3.5 450 2.3  
10500 11.2 52.2 200 16 8 6.9 3.8 29.0 84.3 -3.9 403 2.0  
10250 11.6 52.9 190 17 9 6.2 3.4 28.8 83.8 -4.2 381 1.9  
10000 12.1 53.8 185 18 9 6.0 3.3 28.5 83.3 -4.5 361 1.8  
9750 12.5 54.5 180 18 9 6.1 3.3 28.2 82.7 -4.8 341 1.7  
9500 12.9 55.2 180 19 10 6.1 3.3 27.9 82.2 -5.1 320 1.6  
9250 13.4 56.1 175 20 10 6.1 3.3 27.6 81.7 -5.4 300 1.5  
9000 13.8 56.8 170 21 11 6.1 3.3 27.3 81.2 -5.7 280 1.4  
8750 14.2 57.6 165 22 11 6.1 3.3 27.1 80.7 -6.0 259 1.3  
8500 14.7 58.5 155 24 12 6.1 3.4 26.8 80.2 -6.3 239 1.2  
8250 15.2 59.4 150 26 13 8.4 4.6 26.5 79.8 -6.6 217 1.1  
8000 15.9 60.6 145 28 14 10.0 5.5 26.5 79.8 -6.6 188 1.0  
7750 16.6 61.9 145 28 15 9.6 5.2 26.5 79.8 -6.6 159 0.8  
7500 17.3 63.1 145 28 15 9.6 5.3 26.5 79.7 -6.7 131 0.7  
7250 18.0 64.4 145 29 15 9.8 5.4 26.5 79.7 -6.7 102 0.5  
7000 18.7 65.7 145 29 15 9.1 5.0 26.5 79.7 -6.7 73 0.4  
6750 19.3 66.7 145 30 15 4.8 2.6 26.3 79.4 -6.9 50 0.3  
6500 19.4 66.9 145 31 16 2.4 1.3 25.8 78.4 -7.5 37 0.2  
6250 19.6 67.3 150 32 16 3.1 1.7 25.3 77.5 -8.1 24 0.1  
6000 19.8 67.6 150 33 17 2.9 1.6 24.8 76.6 -8.6 11 0.1  
5750 20.0 68.0 150 30 15 3.1 1.7 24.3 75.7 -9.2 M M  
5500 20.2 68.4 145 25 13 2.4 1.3 23.8 74.8 -9.8 M M  
5250 20.3 68.5 145 21 11 1.8 1.0 23.2 73.7 -10.4 M M  
5000 20.4 68.7 140 17 9 1.2 0.6 22.5 72.6 -11.1 M M  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
05/31/2020 AT 0900 MDT | 05/31/2020 AT 1200 MDT  
|  
CAPE... +501.1 LI... -1.9 | CAPE... +700.5 LI... -2.9  
CINH... -124.1 K INDEX... +27.1 | CINH... -3.3 K INDEX... +31.3  
|  
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 -65.6 -86.1 215 16 8 -0.7 -0.4 | -65.4 -85.7 215 16 8 -0.8 -0.5  
45000 -65.2 -85.4 210 24 13 4.1 2.3 | -65.2 -85.4 210 24 13 4.1 2.3  
40000 -58.1 -72.6 200 26 13 8.7 4.8 | -58.2 -72.8 205 28 15 8.7 4.7  
38000 -53.0 -63.4 200 25 13 8.5 4.7 | -53.0 -63.4 205 27 14 8.5 4.7  
36000 -47.9 -54.2 205 24 12 8.5 4.7 | -47.9 -54.2 205 25 13 8.5 4.7  
34000 -42.8 -45.0 210 22 11 8.4 4.6 | -43.0 -45.4 210 23 12 8.2 4.5  
32000 -37.8 -36.0 215 20 10 8.2 4.5 | -38.0 -36.4 215 20 10 8.1 4.4  
30000 -33.0 -27.4 215 19 10 7.8 4.3 | -33.1 -27.6 220 19 10 8.2 4.5  
29000 -30.7 -23.3 215 18 9 7.8 4.3 | -30.6 -23.1 220 18 9 8.2 4.5  
28000 -28.4 -19.1 215 17 9 7.7 4.2 | -28.2 -18.8 225 17 9 8.0 4.4  
27000 -26.2 -15.2 220 17 9 7.2 3.9 | -26.0 -14.8 225 17 9 7.3 4.0  
26000 -24.1 -11.4 220 16 8 7.2 3.9 | -23.8 -10.8 225 17 9 7.3 4.0  
25000 -21.9 -7.4 225 16 8 7.2 3.9 | -21.0 -5.8 230 16 8 7.1 3.9  
24000 -19.3 -2.7 225 15 8 6.9 3.8 | -19.1 -2.4 230 16 8 6.6 3.6  
23000 -17.2 1.0 230 15 8 7.0 3.8 | -17.1 1.2 230 15 8 6.7 3.6  
22000 -15.2 4.6 230 15 7 6.9 3.8 | -15.2 4.6 230 15 8 6.7 3.7  
21000 -13.2 8.2 230 14 7 6.8 3.7 | -13.2 8.2 230 15 8 6.8 3.8  
20000 -11.2 11.8 230 14 7 6.8 3.7 | -11.2 11.8 230 14 7 6.9 3.8  
19500 -10.2 13.6 230 14 7 6.8 3.7 | -10.2 13.6 230 14 7 6.9 3.8  
19000 -9.2 15.4 230 14 7 6.5 3.6 | -9.2 15.4 230 13 7 7.1 3.9  
18500 -8.3 17.1 230 13 7 6.6 3.6 | -8.2 17.2 225 13 7 7.1 3.9  
18000 -7.3 18.9 230 13 7 7.0 3.8 | -7.1 19.2 225 13 6 7.2 3.9  
17500 -6.3 20.7 230 13 7 7.3 4.0 | -6.1 21.0 225 12 6 7.2 4.0  
17000 -5.2 22.6 230 12 6 7.4 4.1 | -5.1 22.8 225 12 6 7.3 4.0  
16500 -4.1 24.6 230 12 6 8.1 4.5 | -4.0 24.8 220 11 6 7.5 4.1  
16000 -2.9 26.8 230 11 6 8.1 4.4 | -2.9 26.8 220 11 6 7.4 4.1  
15500 -1.8 28.8 230 10 5 8.5 4.6 | -1.8 28.8 215 10 5 8.3 4.5  
15000 -0.5 31.1 230 10 5 8.5 4.7 | -0.6 30.9 215 10 5 8.4 4.6  
14500 0.7 33.3 230 9 5 8.7 4.8 | 0.6 33.1 215 10 5 8.8 4.8  
14000 2.0 35.6 225 9 5 8.8 4.8 | 1.9 35.4 210 10 5 9.1 5.0  
13500 3.3 37.9 225 8 4 8.9 4.9 | 3.3 37.9 210 10 5 9.1 5.0  
13000 4.6 40.3 225 8 4 8.9 4.9 | 4.6 40.3 210 9 5 9.3 5.1  
12500 5.9 42.6 225 8 4 8.9 4.9 | 6.0 42.8 210 9 5 9.3 5.1  
12000 7.2 45.0 220 8 4 8.7 4.7 | 7.4 45.3 210 9 5 9.4 5.2  
11500 8.5 47.3 220 7 4 8.7 4.8 | 8.8 47.8 205 9 5 9.4 5.1  
11000 9.7 49.5 215 8 4 8.1 4.4 | 10.1 50.2 205 9 5 9.2 5.0  
10500 10.9 51.6 215 8 4 7.3 4.0 | 11.5 52.7 205 9 4 8.0 4.4  
10250 11.4 52.5 215 7 4 7.1 3.9 | 12.0 53.6 205 9 4 8.4 4.6  
10000 12.0 53.6 215 8 4 8.4 4.6 | 12.8 55.0 205 8 4 10.3 5.6  
9750 12.6 54.7 210 8 4 8.3 4.6 | 13.5 56.3 205 8 4 9.7 5.3  
9500 13.2 55.8 210 8 4 8.4 4.6 | 14.2 57.6 205 8 4 10.1 5.5  
9250 13.8 56.8 205 8 4 9.0 4.9 | 15.0 59.0 205 8 4 10.4 5.7  
9000 14.4 57.9 205 9 4 7.2 4.0 | 15.7 60.3 205 8 4 9.7 5.3  
8750 14.9 58.8 200 9 4 5.6 3.1 | 16.4 61.5 205 8 4 9.0 4.9  
8500 15.3 59.5 195 9 4 6.1 3.4 | 17.8 64.0 200 8 4 9.6 5.3  
8250 15.7 60.3 195 9 5 6.2 3.4 | 18.5 65.3 200 8 4 10.0 5.5  
8000 16.2 61.2 195 9 5 6.2 3.4 | 19.3 66.7 200 7 4 10.4 5.7  
7750 17.0 62.6 185 8 4 5.6 3.1 | 20.0 68.0 200 7 4 10.0 5.5  
7500 17.4 63.3 180 8 4 4.7 2.6 | 20.8 69.4 200 7 4 9.5 5.2  
7250 17.7 63.9 175 8 4 5.1 2.8 | 21.5 70.7 200 7 4 9.7 5.3  
7000 18.2 64.8 170 8 4 7.5 4.1 | 22.2 72.0 200 7 4 10.4 5.7  
6750 18.7 65.7 165 7 3 7.4 4.0 | 23.0 73.4 200 7 3 11.0 6.0  
6500 19.2 66.6 160 6 3 6.1 3.3 | 23.9 75.0 200 7 3 11.6 6.4  
6250 19.6 67.3 155 6 3 6.0 3.3 | 24.7 76.5 200 6 3 10.3 5.7  
6000 20.1 68.2 150 6 3 8.9 4.9 | 25.5 77.9 200 6 3 12.1 6.7  
5750 20.9 69.6 150 4 2 15.7 8.6 | 26.7 80.1 200 6 3 24.1 13.2  
5500 21.8 71.2 140 4 2 5.1 2.8 | 29.0 84.2 200 5 3 38.0 20.9  
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  
 
05/31/2020 AT 1500 MDT | 05/31/2020 AT 1800 MDT  
|  
CAPE... +543.6 LI... -2.4 | CAPE... +1052.8 LI... -2.2  
CINH... -4.8 K INDEX... +32.1 | CINH... -86.6 K INDEX... +30.1  
|  
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 -65.8 -86.4 225 15 8 -1.2 -0.6 | -65.6 -86.1 225 12 6 -1.6 -0.9  
45000 -65.7 -86.3 220 23 12 4.6 2.5 | -66.0 -86.8 215 18 9 4.9 2.7  
40000 -58.0 -72.4 205 28 15 8.5 4.7 | -57.8 -72.0 215 20 10 8.7 4.8  
38000 -52.9 -63.2 210 25 13 8.5 4.7 | -52.6 -62.7 220 18 9 8.7 4.7  
36000 -47.7 -53.9 215 23 12 8.5 4.7 | -47.3 -53.1 220 16 8 8.7 4.8  
34000 -42.6 -44.7 220 20 11 8.6 4.7 | -42.2 -44.0 225 15 8 8.5 4.6  
32000 -37.4 -35.3 230 19 10 8.5 4.6 | -37.2 -35.0 230 14 7 8.3 4.6  
30000 -32.5 -26.5 230 17 9 8.1 4.5 | -32.3 -26.1 230 13 6 8.0 4.4  
29000 -30.1 -22.2 230 16 8 8.1 4.5 | -29.9 -21.8 230 12 6 8.0 4.4  
28000 -27.6 -17.7 230 16 8 8.0 4.4 | -27.5 -17.5 230 12 6 7.9 4.3  
27000 -25.4 -13.7 230 15 8 7.5 4.1 | -25.3 -13.5 230 12 6 7.4 4.1  
26000 -22.6 -8.7 230 14 7 7.5 4.1 | -22.5 -8.5 230 12 6 7.4 4.1  
25000 -20.3 -4.5 230 14 7 7.1 3.9 | -20.3 -4.5 230 12 6 7.3 4.0  
24000 -18.4 -1.1 225 14 7 6.3 3.4 | -18.3 -0.9 230 12 6 6.7 3.7  
23000 -16.6 2.1 225 13 7 6.3 3.4 | -16.4 2.5 230 12 6 6.7 3.7  
22000 -14.8 5.4 225 13 7 6.6 3.6 | -14.4 6.1 230 12 6 6.8 3.7  
21000 -12.7 9.1 225 12 6 7.0 3.9 | -12.4 9.7 230 11 6 6.9 3.8  
20000 -10.7 12.7 225 12 6 7.1 3.9 | -10.3 13.5 230 11 6 6.9 3.8  
19500 -9.7 14.5 225 11 6 7.1 3.9 | -9.3 15.3 230 11 6 6.9 3.8  
19000 -8.6 16.5 220 11 6 7.5 4.1 | -8.3 17.1 230 11 5 7.5 4.1  
18500 -7.5 18.5 220 11 6 7.5 4.1 | -7.2 19.0 225 11 5 7.4 4.1  
18000 -6.5 20.3 220 11 6 7.5 4.1 | -6.1 21.0 225 10 5 7.6 4.2  
17500 -5.4 22.3 220 11 6 7.6 4.1 | -5.0 23.0 225 10 5 7.8 4.3  
17000 -4.3 24.3 220 11 5 7.6 4.2 | -3.9 25.0 220 10 5 7.8 4.3  
16500 -3.2 26.2 220 10 5 7.6 4.2 | -2.7 27.1 220 10 5 8.0 4.4  
16000 -2.1 28.2 220 10 5 7.6 4.2 | -1.5 29.3 220 10 5 8.0 4.4  
15500 -1.0 30.2 220 10 5 7.8 4.3 | -0.4 31.3 220 10 5 8.2 4.5  
15000 0.2 32.4 215 10 5 7.9 4.3 | 0.8 33.4 215 10 5 8.2 4.5  
14500 1.3 34.3 215 10 5 8.7 4.8 | 2.0 35.6 215 10 5 8.6 4.7  
14000 2.7 36.9 215 10 5 9.4 5.2 | 3.4 38.1 215 10 5 9.0 4.9  
13500 4.1 39.4 215 10 5 9.4 5.2 | 4.7 40.5 215 10 5 9.0 4.9  
13000 5.5 41.9 220 9 5 9.2 5.1 | 6.0 42.8 215 10 5 8.9 4.9  
12500 6.8 44.2 220 9 5 9.3 5.1 | 7.3 45.1 215 10 5 8.9 4.9  
12000 8.2 46.8 220 9 5 9.3 5.1 | 8.6 47.5 220 10 5 8.9 4.9  
11500 9.6 49.3 220 9 5 9.3 5.1 | 9.9 49.8 220 10 5 9.0 4.9  
11000 10.9 51.6 220 9 4 8.5 4.7 | 11.2 52.2 220 10 5 7.8 4.3  
10500 12.1 53.8 220 8 4 10.3 5.7 | 12.3 54.1 220 10 5 10.3 5.6  
10250 13.0 55.4 225 9 4 10.9 6.0 | 13.2 55.8 225 10 5 10.7 5.9  
10000 13.7 56.7 225 9 4 8.9 4.9 | 13.8 56.8 225 10 5 7.8 4.3  
9750 14.4 57.9 225 9 4 9.4 5.2 | 14.4 57.9 225 10 5 8.6 4.7  
9500 15.1 59.2 225 8 4 9.4 5.2 | 15.0 59.0 225 10 5 8.4 4.6  
9250 15.8 60.4 225 8 4 9.8 5.4 | 15.7 60.3 225 11 5 8.0 4.4  
9000 16.5 61.7 225 8 4 9.6 5.3 | 16.2 61.2 225 11 6 7.9 4.3  
8750 17.9 64.2 225 8 4 9.3 5.1 | 16.8 62.2 225 11 6 8.2 4.5  
8500 18.5 65.3 225 8 4 9.1 5.0 | 18.0 64.4 225 11 6 6.6 3.6  
8250 19.2 66.6 225 8 4 9.5 5.2 | 18.4 65.1 225 12 6 6.8 3.7  
8000 20.0 68.0 225 8 4 10.3 5.6 | 19.0 66.2 225 11 6 8.6 4.7  
7750 20.7 69.3 230 8 4 9.8 5.4 | 19.6 67.3 225 11 6 7.9 4.3  
7500 21.4 70.5 230 8 4 9.0 4.9 | 20.1 68.2 225 11 6 6.6 3.6  
7250 22.1 71.8 225 8 4 9.2 5.1 | 20.6 69.1 225 12 6 6.5 3.6  
7000 22.8 73.0 230 8 4 10.3 5.6 | 21.2 70.2 225 12 6 8.7 4.8  
6750 23.6 74.5 230 8 4 11.1 6.1 | 21.8 71.2 225 10 5 8.7 4.8  
6500 24.5 76.1 230 8 4 11.5 6.3 | 22.3 72.1 225 10 5 7.5 4.1  
6250 25.3 77.5 230 7 4 10.8 5.9 | 22.9 73.2 225 10 5 7.7 4.2  
6000 26.1 79.0 230 7 4 10.6 5.8 | 23.5 74.3 225 10 5 8.5 4.7  
5750 27.0 80.6 230 7 4 17.5 9.6 | 24.0 75.2 225 8 4 7.4 4.0  
5500 29.0 84.2 230 6 3 42.3 23.2 | 24.0 75.2 230 7 4 -5.7 -3.1  
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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