060  
UXUS97 KGJT 221258  
SRGGJT  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO  
0657 MDT WEDNESDAY, MARCH 22, 2017  
 
THIS FORECAST IS FOR WEDNESDAY, MARCH 22, 2017:  
 
IF THE TRIGGER TEMPERATURE OF 71.2 F/21.8 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... GOOD  
MAXIMUM RATE OF LIFT........................ 547 FT/MIN (2.8 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 14939 FT MSL (10100 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 74.0 F/23.8 C  
TIME OF TRIGGER TEMPERATURE.................... 1315 MDT  
TIME OF OVERDEVELOPMENT........................ NONE  
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST OPAQUE MIDDLE  
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS  
HEIGHT OF THE -3 THERMAL INDEX................. 7203 FT MSL (2364 FT AGL)  
THERMAL SOARING OUTLOOK FOR THURSDAY 03/23..... GOOD  
 
WAVE SOARING INDEX............................. NOT AVAILABLE  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 07:13:52 / 19:27:25 MDT  
TOTAL POSSIBLE SUNSHINE........... 12 HR 13 MIN 34 SEC (733 MIN 34 SEC)  
ALTITUDE OF SUN AT 13:20:49 MDT... 51.83 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 03/22/2017 AT 0600 MDT  
 
FREEZING LEVEL.................. 12341 FT MSL (7502 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 17723 FT MSL (12884 FT AGL)  
LIFTED CONDENSATION LEVEL....... 17561 FT MSL (12722 FT AGL)  
LIFTED INDEX.................... +2.7  
K INDEX......................... +9.6  
 
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 -63.7 -82.7 245 34 18 5.6 3.1 92.6 198.7 39.7 M M  
45000 -57.4 -71.3 245 44 23 5.5 3.0 78.7 173.6 33.9 M M  
40000 -48.9 -56.0 235 71 36 6.2 3.4 67.9 154.2 29.3 M M  
38000 -48.7 -55.7 245 63 32 -3.8 -2.1 59.3 138.8 24.3 M M  
36000 -54.3 -65.7 250 77 40 3.9 2.1 42.7 108.9 13.4 M M  
34000 -52.0 -61.6 250 80 41 8.8 4.8 37.5 99.6 10.1 M M  
32000 -46.7 -52.1 245 70 36 8.8 4.9 36.8 98.2 9.8 M M  
30000 -40.9 -41.6 245 65 33 8.3 4.6 36.0 96.8 9.5 M M  
29000 -38.4 -37.1 245 64 33 8.3 4.6 35.2 95.4 9.0 M M  
28000 -35.9 -32.6 245 62 32 8.3 4.6 34.6 94.3 8.7 M M  
27000 -33.4 -28.1 245 61 31 8.3 4.6 34.2 93.5 8.4 M M  
26000 -31.0 -23.8 245 60 31 8.3 4.6 33.8 92.8 8.2 M M  
25000 -28.6 -19.5 240 60 31 7.0 3.8 33.1 91.6 7.7 M M  
24000 -26.5 -15.7 230 58 30 6.9 3.8 32.0 89.6 6.9 M M  
23000 -24.5 -12.1 225 60 31 6.9 3.8 30.9 87.7 6.1 M M  
22000 -22.4 -8.3 225 62 32 6.9 3.8 30.0 86.0 5.3 M M  
21000 -20.4 -4.7 230 55 28 6.9 3.8 28.9 84.0 4.4 M M  
20000 -18.4 -1.1 235 48 25 7.0 3.8 27.9 82.2 3.6 M M  
19500 -17.4 0.7 230 48 25 4.7 2.6 27.3 81.1 3.1 M M  
19000 -16.8 1.8 225 48 25 0.2 0.1 26.3 79.3 2.3 M M  
18500 -16.9 1.6 220 47 24 5.1 2.8 24.4 75.9 0.7 M M  
18000 -15.6 3.9 215 46 24 9.3 5.1 24.2 75.6 0.6 M M  
17500 -14.3 6.3 215 45 23 8.7 4.8 24.1 75.4 0.5 M M  
17000 -13.0 8.6 215 44 23 8.8 4.8 23.9 75.1 0.3 M M  
16500 -10.9 12.4 220 42 22 9.4 5.1 23.8 74.9 0.2 M M  
16000 -9.5 14.9 220 41 21 9.4 5.2 23.8 74.8 0.1 M M  
15500 -8.1 17.4 225 39 20 9.4 5.2 23.7 74.6 0.0 M M  
15000 -6.7 19.9 225 36 19 9.6 5.2 23.6 74.6 -0.0 943 4.8  
14500 -5.5 22.1 220 32 17 6.6 3.6 23.4 74.2 -0.2 890 4.5  
14000 -4.5 23.9 220 29 15 8.6 4.7 22.9 73.3 -0.8 848 4.3  
13500 -3.1 26.4 220 27 14 9.6 5.3 22.9 73.3 -0.8 791 4.0  
13000 -1.7 28.9 215 25 13 9.3 5.1 22.9 73.2 -0.9 734 3.7  
12500 -0.3 31.5 215 23 12 9.3 5.1 22.8 73.0 -0.9 677 3.4  
12000 1.1 34.0 210 21 11 9.3 5.1 22.8 73.0 -0.9 620 3.2  
11500 2.5 36.5 215 20 10 9.3 5.1 22.7 72.8 -1.0 563 2.9  
11000 3.9 39.0 220 20 10 9.3 5.1 22.6 72.7 -1.1 506 2.6  
10500 5.3 41.5 220 19 10 10.0 5.5 22.5 72.6 -1.1 449 2.3  
10250 6.1 43.0 225 19 10 9.9 5.4 22.6 72.6 -1.1 419 2.1  
10000 6.8 44.2 225 19 10 8.8 4.8 22.5 72.6 -1.1 391 2.0  
9750 7.4 45.3 225 18 9 8.6 4.7 22.4 72.4 -1.2 364 1.8  
9500 8.1 46.6 225 17 9 8.6 4.7 22.4 72.2 -1.3 337 1.7  
9250 8.7 47.7 225 17 9 8.6 4.7 22.3 72.1 -1.4 311 1.6  
9000 9.3 48.7 225 16 8 8.6 4.7 22.2 72.0 -1.4 284 1.4  
8750 10.0 50.0 225 16 8 8.6 4.7 22.1 71.8 -1.5 257 1.3  
8500 10.6 51.1 225 15 8 8.6 4.7 22.0 71.6 -1.6 231 1.2  
8250 11.3 52.3 225 15 7 8.6 4.7 21.9 71.5 -1.7 204 1.0  
8000 11.9 53.4 225 14 7 8.7 4.8 21.8 71.3 -1.8 178 0.9  
7750 12.6 54.7 220 14 7 8.2 4.5 21.8 71.2 -1.9 151 0.8  
7500 13.0 55.4 210 13 7 3.7 2.0 21.5 70.7 -2.2 129 0.7  
7250 13.1 55.6 200 13 7 1.5 0.8 20.9 69.6 -2.8 119 0.6  
7000 13.4 56.1 190 14 7 5.9 3.2 20.4 68.7 -3.3 105 0.5  
6750 13.9 57.0 185 15 8 8.1 4.4 20.2 68.4 -3.5 80 0.4  
6500 14.5 58.1 175 16 8 7.5 4.1 20.1 68.1 -3.7 56 0.3  
6250 15.1 59.2 170 18 9 7.8 4.3 19.9 67.8 -3.8 32 0.2  
6000 15.6 60.1 165 20 10 7.1 3.9 19.8 67.6 -4.0 8 0.0  
5750 16.2 61.2 160 18 9 9.6 5.3 19.6 67.3 -4.2 M M  
5500 16.8 62.2 155 14 7 0.3 0.2 19.4 67.0 -4.4 M M  
5250 16.1 61.0 145 11 6 -13.7 -7.5 18.1 64.5 -5.8 M M  
5000 15.1 59.2 130 9 5 -6.9 -3.8 16.4 61.6 -7.5 M M  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
03/22/2017 AT 0900 MDT | 03/22/2017 AT 1200 MDT  
|  
K INDEX... +12.7 LI... +1.1 | K INDEX... +8.5 LI... +0.9  
CAPE... 0.0 CIN... 0.0 | CAPE... +0.1 CIN... -1.7  
|  
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 -83.2 240 48 25 5.1 2.8 | -63.1 -81.6 240 47 24 4.8 2.6  
45000 -56.4 -69.5 245 55 28 4.6 2.5 | -56.0 -68.8 240 57 29 4.6 2.5  
40000 -49.2 -56.6 245 68 35 4.4 2.4 | -48.7 -55.7 240 75 39 4.4 2.4  
38000 -49.5 -57.1 245 74 38 -2.1 -1.2 | -49.2 -56.6 240 81 42 -3.0 -1.7  
36000 -50.8 -59.4 245 79 41 -2.1 -1.2 | -51.1 -60.0 240 86 44 -3.0 -1.7  
34000 -50.3 -58.5 240 83 43 6.9 3.8 | -51.1 -60.0 235 89 46 6.8 3.7  
32000 -46.1 -51.0 240 82 42 7.0 3.8 | -46.9 -52.4 235 87 45 7.0 3.8  
30000 -41.7 -43.1 240 82 42 8.3 4.5 | -42.4 -44.3 235 84 43 8.5 4.6  
29000 -39.2 -38.6 240 81 42 8.3 4.5 | -39.9 -39.8 235 81 42 8.5 4.6  
28000 -36.7 -34.1 240 80 41 8.3 4.5 | -36.7 -34.1 235 77 40 8.5 4.6  
27000 -33.7 -28.7 240 78 40 7.7 4.2 | -34.3 -29.7 235 74 38 7.5 4.1  
26000 -31.4 -24.5 240 73 38 7.8 4.3 | -32.0 -25.6 235 69 36 7.5 4.1  
25000 -29.1 -20.4 240 69 35 7.8 4.3 | -29.8 -21.6 235 65 33 7.5 4.1  
24000 -26.8 -16.2 240 64 33 7.2 3.9 | -27.5 -17.5 235 61 31 8.8 4.8  
23000 -24.7 -12.5 240 61 31 7.2 4.0 | -24.8 -12.6 230 60 31 8.9 4.9  
22000 -22.5 -8.5 235 58 30 7.2 4.0 | -22.2 -8.0 230 59 30 8.9 4.9  
21000 -20.5 -4.9 230 55 28 6.1 3.3 | -20.0 -4.0 230 58 30 5.1 2.8  
20000 -18.7 -1.7 230 51 26 6.2 3.4 | -18.4 -1.1 230 55 28 5.4 3.0  
19500 -17.8 -0.0 230 50 26 6.2 3.4 | -17.6 0.3 230 54 28 5.4 3.0  
19000 -16.9 1.6 230 48 25 6.2 3.4 | -16.8 1.8 235 52 27 5.4 2.9  
18500 -16.0 3.2 230 46 24 5.9 3.3 | -16.0 3.2 235 51 26 5.6 3.1  
18000 -15.1 4.8 230 44 23 6.1 3.3 | -15.1 4.8 230 48 25 5.7 3.1  
17500 -14.2 6.4 230 42 22 7.4 4.1 | -14.3 6.3 230 45 23 7.0 3.9  
17000 -12.8 9.0 230 40 21 8.9 4.9 | -13.0 8.6 230 43 22 8.9 4.9  
16500 -11.5 11.3 230 39 20 9.0 4.9 | -11.6 11.1 230 40 21 9.0 5.0  
16000 -10.2 13.6 230 36 19 7.8 4.3 | -10.4 13.3 230 37 19 7.8 4.3  
15500 -9.0 15.8 230 34 17 7.9 4.4 | -9.1 15.6 230 34 17 7.9 4.3  
15000 -7.9 17.8 230 31 16 7.4 4.1 | -7.9 17.8 230 31 16 8.7 4.8  
14500 -6.8 19.8 230 29 15 7.5 4.1 | -6.5 20.3 230 29 15 8.8 4.8  
14000 -5.8 21.6 230 26 13 7.7 4.2 | -5.2 22.6 225 28 14 7.8 4.3  
13500 -4.6 23.7 225 24 12 7.8 4.3 | -3.7 25.3 220 26 14 7.1 3.9  
13000 -2.9 26.8 220 21 11 8.7 4.8 | -2.6 27.3 220 25 13 7.9 4.3  
12500 -1.6 29.1 220 20 10 8.6 4.7 | -1.5 29.3 220 24 12 7.9 4.3  
12000 -0.3 31.5 215 19 10 8.8 4.8 | -0.4 31.3 220 23 12 8.4 4.6  
11500 1.0 33.8 215 18 9 8.9 4.9 | 0.9 33.6 215 23 12 8.5 4.7  
11000 2.2 36.0 210 17 9 7.2 3.9 | 2.1 35.8 215 24 12 7.5 4.1  
10500 3.3 37.9 210 16 8 6.3 3.5 | 3.2 37.8 215 24 12 6.8 3.7  
10250 3.8 38.8 210 15 8 10.4 5.7 | 3.7 38.7 215 24 12 10.0 5.5  
10000 4.7 40.5 210 15 8 11.3 6.2 | 4.6 40.3 215 24 12 10.6 5.8  
9750 5.4 41.7 210 15 7 7.7 4.2 | 5.2 41.4 210 24 12 7.7 4.2  
9500 6.0 42.8 215 14 7 9.0 4.9 | 5.8 42.4 210 23 12 8.6 4.7  
9250 6.6 43.9 215 14 7 7.3 4.0 | 6.4 43.5 210 23 12 7.8 4.3  
9000 7.1 44.8 210 14 7 6.7 3.7 | 7.0 44.6 210 23 12 8.2 4.5  
8750 7.7 45.9 210 14 7 7.8 4.3 | 7.6 45.7 205 22 11 8.9 4.9  
8500 8.3 46.9 210 14 7 7.4 4.1 | 8.3 46.9 205 21 11 8.7 4.8  
8250 8.8 47.8 210 14 7 8.3 4.5 | 8.9 48.0 205 20 11 8.4 4.6  
8000 9.4 48.9 205 14 7 7.3 4.0 | 9.5 49.1 200 19 10 7.5 4.1  
7750 9.9 49.8 205 15 8 6.0 3.3 | 10.0 50.0 195 17 9 6.9 3.8  
7500 10.4 50.7 200 15 8 5.4 3.0 | 10.5 50.9 190 15 8 7.6 4.2  
7250 10.7 51.3 195 15 8 4.2 2.3 | 11.1 52.0 185 14 7 9.1 5.0  
7000 11.0 51.8 190 16 8 3.4 1.9 | 11.8 53.2 185 13 7 9.7 5.3  
6750 11.2 52.2 180 16 8 3.2 1.7 | 12.5 54.5 185 13 7 9.2 5.0  
6500 11.3 52.3 175 16 8 -0.6 -0.3 | 13.2 55.8 185 13 7 10.3 5.7  
6250 11.1 52.0 170 14 7 -3.4 -1.9 | 14.1 57.4 185 12 6 11.6 6.4  
6000 10.8 51.4 160 12 6 -3.6 -2.0 | 14.9 58.8 185 12 6 10.8 5.9  
5750 10.5 50.9 145 8 4 -1.8 -1.0 | 15.7 60.3 185 11 6 10.7 5.9  
5500 10.6 51.1 125 7 3 3.5 1.9 | 16.6 61.9 185 11 6 12.5 6.8  
5250 10.9 51.6 125 6 3 4.2 2.3 | 17.5 63.5 185 11 5 14.0 7.7  
5000 M M M M M M M | M M M M M M M  
 
03/22/2017 AT 1500 MDT | 03/22/2017 AT 1800 MDT  
|  
K INDEX... +21.1 LI... +0.7 | K INDEX... +17.5 LI... +1.9  
CAPE... +6.6 CIN... -3.2 | CAPE... +0.2 CIN... -0.7  
|  
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 -62.3 -80.1 240 49 25 4.2 2.3 | -62.0 -79.6 240 54 28 3.8 2.1  
45000 -55.9 -68.6 240 62 32 4.2 2.3 | -56.3 -69.3 240 69 36 3.8 2.1  
40000 -49.3 -56.7 240 80 41 4.0 2.2 | -50.6 -59.1 235 84 43 3.8 2.1  
38000 -49.9 -57.8 235 86 44 -3.2 -1.8 | -50.2 -58.4 235 87 45 -1.5 -0.8  
36000 -51.9 -61.4 235 91 47 -3.2 -1.8 | -51.1 -60.0 230 89 46 -1.5 -0.8  
34000 -51.9 -61.4 230 93 48 7.3 4.0 | -50.6 -59.1 225 89 46 6.2 3.4  
32000 -47.4 -53.3 225 87 45 7.5 4.1 | -46.9 -52.4 220 84 43 6.3 3.4  
30000 -42.5 -44.5 225 79 41 9.6 5.3 | -42.5 -44.5 215 79 40 9.4 5.2  
29000 -39.7 -39.5 220 73 38 9.6 5.3 | -39.6 -39.3 215 74 38 9.4 5.2  
28000 -36.8 -34.2 220 67 35 9.6 5.3 | -36.8 -34.2 215 70 36 9.5 5.2  
27000 -33.3 -27.9 220 61 31 8.2 4.5 | -34.1 -29.4 220 66 34 7.8 4.3  
26000 -30.9 -23.6 220 60 31 8.3 4.5 | -31.8 -25.2 220 66 34 7.7 4.2  
25000 -28.4 -19.1 225 58 30 8.3 4.6 | -29.5 -21.1 220 66 34 7.7 4.2  
24000 -26.0 -14.8 225 57 29 6.7 3.7 | -27.2 -17.0 220 66 34 7.9 4.3  
23000 -24.1 -11.4 225 56 29 6.6 3.6 | -24.8 -12.6 225 61 31 8.0 4.4  
22000 -22.1 -7.8 225 55 29 6.6 3.6 | -22.4 -8.3 225 56 29 8.1 4.4  
21000 -20.2 -4.4 225 54 28 6.2 3.4 | -20.1 -4.2 230 52 27 5.8 3.2  
20000 -18.4 -1.1 225 51 26 6.2 3.4 | -18.5 -1.3 230 52 27 5.5 3.0  
19500 -17.5 0.5 225 50 26 6.2 3.4 | -17.7 0.1 230 52 27 5.5 3.0  
19000 -16.6 2.1 225 49 25 6.2 3.4 | -16.9 1.6 230 52 27 5.5 3.0  
18500 -15.6 3.9 225 47 24 6.8 3.7 | -16.0 3.2 230 52 27 6.8 3.8  
18000 -14.6 5.7 225 45 23 6.9 3.8 | -14.9 5.2 230 50 26 7.7 4.2  
17500 -13.6 7.5 225 43 22 6.6 3.6 | -13.8 7.2 230 47 24 7.7 4.2  
17000 -12.7 9.1 225 41 21 5.8 3.2 | -12.8 9.0 230 44 23 5.9 3.2  
16500 -11.9 10.6 225 39 20 5.9 3.2 | -11.9 10.6 230 41 21 6.0 3.3  
16000 -11.1 12.0 225 37 19 5.2 2.9 | -11.0 12.2 225 39 20 6.4 3.5  
15500 -10.3 13.5 220 34 18 5.2 2.9 | -9.5 14.9 220 37 19 6.4 3.5  
15000 -9.4 15.1 215 31 16 6.8 3.7 | -8.5 16.7 220 35 18 7.4 4.0  
14500 -8.3 17.1 215 30 15 7.3 4.0 | -7.4 18.7 215 34 17 7.3 4.0  
14000 -7.3 18.9 210 29 15 8.1 4.4 | -6.3 20.7 210 32 17 7.6 4.1  
13500 -5.3 22.5 210 28 14 8.7 4.8 | -5.2 22.6 205 31 16 7.6 4.2  
13000 -3.9 25.0 205 27 14 10.0 5.5 | -4.0 24.8 200 29 15 8.1 4.5  
12500 -2.4 27.7 205 27 14 10.1 5.5 | -2.8 27.0 200 28 15 8.4 4.6  
12000 -0.9 30.4 205 26 13 9.9 5.4 | -1.5 29.3 195 27 14 9.1 5.0  
11500 0.6 33.1 205 26 13 10.0 5.5 | -0.1 31.8 195 27 14 9.5 5.2  
11000 2.0 35.6 205 25 13 8.6 4.7 | 1.3 34.3 195 27 14 8.9 4.9  
10500 3.2 37.8 210 24 12 8.2 4.5 | 2.6 36.7 190 27 14 7.9 4.4  
10250 3.9 39.0 210 23 12 11.6 6.3 | 3.3 37.9 190 27 14 11.4 6.2  
10000 4.8 40.6 210 23 12 11.7 6.4 | 4.2 39.6 190 27 14 11.8 6.5  
9750 5.5 41.9 210 22 12 9.3 5.1 | 4.9 40.8 190 26 14 8.7 4.8  
9500 6.3 43.3 210 22 11 9.9 5.4 | 5.6 42.1 190 26 14 9.5 5.2  
9250 7.0 44.6 210 22 11 10.0 5.5 | 6.3 43.3 190 26 13 9.4 5.2  
9000 7.7 45.9 210 21 11 9.9 5.5 | 7.1 44.8 185 26 13 9.5 5.2  
8750 8.5 47.3 210 21 11 9.8 5.4 | 7.8 46.0 185 26 13 9.6 5.2  
8500 9.2 48.6 210 21 11 9.5 5.2 | 8.5 47.3 185 25 13 9.3 5.1  
8250 9.9 49.8 210 20 11 11.1 6.1 | 9.2 48.6 185 25 13 10.3 5.6  
8000 10.8 51.4 210 20 10 10.4 5.7 | 10.0 50.0 185 25 13 10.0 5.5  
7750 11.4 52.5 210 20 10 8.3 4.6 | 10.7 51.3 185 25 13 8.8 4.8  
7500 12.1 53.8 210 20 10 9.1 5.0 | 11.3 52.3 185 24 12 9.0 4.9  
7250 12.8 55.0 210 19 10 10.7 5.9 | 12.0 53.6 185 24 12 9.7 5.3  
7000 13.7 56.7 210 19 10 10.8 5.9 | 12.8 55.0 185 23 12 10.0 5.5  
6750 14.4 57.9 210 19 10 9.2 5.1 | 13.5 56.3 180 23 12 9.1 5.0  
6500 15.1 59.2 210 18 9 9.8 5.4 | 14.2 57.6 180 22 11 9.4 5.2  
6250 15.8 60.4 210 18 9 10.7 5.9 | 14.9 58.8 180 21 11 10.7 5.8  
6000 16.6 61.9 210 17 9 10.5 5.8 | 15.7 60.3 180 20 10 10.5 5.8  
5750 17.4 63.3 210 16 8 9.9 5.4 | 16.5 61.7 180 18 9 9.2 5.1  
5500 18.1 64.6 210 15 8 8.9 4.9 | 17.1 62.8 175 16 8 6.8 3.7  
5250 18.7 65.7 210 14 7 8.3 4.5 | 17.4 63.3 180 15 8 3.7 2.0  
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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