014  
UXUS97 KBOU 260122  
SRGBOU  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO  
0122 UTC SATURDAY, MAY 26, 2018  
 
THIS FORECAST IS FOR SATURDAY, MAY 26, 2018:  
 
IF THE TRIGGER TEMPERATURE OF 84.7 F/29.3 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... EXCELLENT  
MAXIMUM RATE OF LIFT........................ 1570 FT/MIN (8.0 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 21324 FT MSL (16017 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 94.0 F/34.9 C  
TIME OF TRIGGER TEMPERATURE.................... 1115 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................. 15381 FT MSL (10075 FT AGL)  
THERMAL SOARING OUTLOOK FOR SUNDAY 05/27....... POOR  
 
WAVE SOARING INDEX............................. POOR  
WAVE SOARING INDEX TREND (TO 1700 MST)......... LITTLE CHANGE  
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE  
WEAK PVA/NVA (THROUGH 1700 MST)................ NEITHER  
POTENTIAL HEIGHT OF WAVE....................... 45342 FT MSL (40035 FT AGL)  
WAVE SOARING OUTLOOK FOR SUNDAY 05/27.......... POOR  
 
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.................... 05:36:37 / 20:16:18 MST  
TOTAL POSSIBLE SUNSHINE........... 14 HR 39 MIN 41 SEC (879 MIN 41 SEC)  
ALTITUDE OF SUN AT 12:56:40 MST... 71.43 DEGREES  
 
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 05/26/2018 AT 0500 MST  
 
FREEZING LEVEL.................. 15783 FT MSL (10476 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 19910 FT MSL (14603 FT AGL)  
LIFTED CONDENSATION LEVEL....... 20378 FT MSL (15071 FT AGL)  
LIFTED INDEX.................... -2.1  
K INDEX......................... +11.0  
 
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 -61.7 -79.1 265 26 13 1.1 0.6 M M M M M  
45000 -60.3 -76.5 260 37 19 0.2 0.1 M M M M M  
40000 -59.8 -75.6 230 26 13 6.5 3.6 M M M M M  
38000 -55.2 -67.4 230 28 14 7.6 4.2 M M M M M  
36000 -50.6 -59.1 230 30 15 7.6 4.2 M M M M M  
34000 -46.0 -50.8 230 27 14 7.6 4.2 M M M M M  
32000 -41.4 -42.5 225 24 12 7.7 4.2 M M M M M  
30000 -36.3 -33.3 230 21 11 9.0 4.9 38.7 101.6 3.2 M M  
29000 -33.0 -27.4 230 20 10 9.0 4.9 38.3 101.0 3.0 M M  
28000 -30.3 -22.5 230 19 10 8.7 4.8 38.2 100.8 2.9 M M  
27000 -27.8 -18.0 235 19 10 8.2 4.5 37.5 99.5 2.4 M M  
26000 -25.3 -13.5 245 18 9 8.2 4.5 36.9 98.5 2.0 M M  
25000 -22.9 -9.2 250 18 9 8.2 4.5 36.5 97.6 1.6 M M  
24000 -20.4 -4.7 250 18 9 8.3 4.6 35.9 96.6 1.1 M M  
23000 -17.9 -0.2 250 19 10 8.3 4.6 35.3 95.6 0.7 M M  
22000 -15.4 4.3 250 19 10 8.3 4.6 34.9 94.9 0.3 M M  
21000 -13.0 8.6 250 18 9 8.2 4.5 34.3 93.8 -0.2 1539 7.8  
20000 -10.5 13.1 245 17 9 8.3 4.5 33.8 92.8 -0.6 1436 7.3  
19500 -9.3 15.3 245 16 8 8.3 4.5 33.6 92.4 -0.9 1385 7.0  
19000 -8.1 17.4 240 16 8 8.1 4.4 33.3 92.0 -1.1 1334 6.8  
18500 -6.9 19.6 240 15 8 8.1 4.4 33.0 91.5 -1.4 1283 6.5  
18000 -5.7 21.7 240 14 7 8.1 4.4 32.8 91.0 -1.6 1233 6.3  
17500 -4.5 23.9 235 14 7 8.1 4.5 32.5 90.4 -1.9 1182 6.0  
17000 -3.3 26.1 235 14 7 8.1 4.5 32.2 89.9 -2.2 1132 5.7  
16500 -2.1 28.2 235 14 7 8.6 4.7 32.0 89.5 -2.5 1081 5.5  
16000 -0.8 30.6 235 14 7 8.7 4.8 31.8 89.2 -2.7 1028 5.2  
15500 0.4 32.7 235 14 7 8.7 4.8 31.6 88.9 -2.9 976 5.0  
15000 2.3 36.1 235 13 7 8.6 4.7 31.3 88.3 -3.2 897 4.6  
14500 3.6 38.5 235 12 6 9.1 5.0 31.1 88.1 -3.4 844 4.3  
14000 5.0 41.0 230 12 6 9.3 5.1 31.1 87.9 -3.5 787 4.0  
13500 6.4 43.5 230 11 6 9.3 5.1 31.0 87.8 -3.6 731 3.7  
13000 7.8 46.0 230 10 5 9.4 5.1 30.9 87.7 -3.7 675 3.4  
12500 9.1 48.4 230 10 5 9.3 5.1 30.9 87.6 -3.8 618 3.1  
12000 10.5 50.9 230 10 5 9.0 4.9 30.8 87.4 -3.9 563 2.9  
11500 11.8 53.2 225 9 5 9.0 4.9 30.7 87.2 -4.0 508 2.6  
11000 13.0 55.4 225 9 5 7.4 4.0 30.4 86.7 -4.3 458 2.3  
10500 14.1 57.4 225 9 5 10.4 5.7 30.0 86.0 -4.7 411 2.1  
10250 15.0 59.0 230 9 5 11.2 6.2 30.2 86.4 -4.5 376 1.9  
10000 15.6 60.1 230 9 5 7.8 4.3 30.1 86.2 -4.7 349 1.8  
9750 16.3 61.3 230 9 5 8.8 4.8 30.0 86.0 -4.8 323 1.6  
9500 16.9 62.4 235 9 5 8.4 4.6 29.9 85.9 -4.9 297 1.5  
9250 17.5 63.5 235 9 5 7.2 4.0 29.8 85.6 -5.0 272 1.4  
9000 18.0 64.4 235 9 5 7.9 4.3 29.6 85.2 -5.3 249 1.3  
8750 18.6 65.5 235 10 5 9.1 5.0 29.5 85.1 -5.4 222 1.1  
8500 19.3 66.7 240 10 5 8.6 4.7 29.4 85.0 -5.5 196 1.0  
8250 19.9 67.8 240 10 5 7.7 4.2 29.3 84.8 -5.6 170 0.9  
8000 20.4 68.7 240 11 6 6.8 3.7 29.1 84.4 -5.8 147 0.7  
7750 20.9 69.6 240 11 6 6.8 3.8 28.9 84.0 -6.0 124 0.6  
7500 21.4 70.5 240 11 6 6.4 3.5 28.7 83.6 -6.3 102 0.5  
7250 21.9 71.4 235 11 6 5.8 3.2 28.4 83.1 -6.6 82 0.4  
7000 22.2 72.0 235 12 6 4.5 2.5 28.0 82.5 -7.0 63 0.3  
6750 22.6 72.7 235 11 6 5.3 2.9 27.6 81.8 -7.4 46 0.2  
6500 22.8 73.0 235 11 6 -3.6 -2.0 27.1 80.8 -7.9 33 0.2  
6250 21.9 71.4 230 11 6 -13.7 -7.5 25.6 78.1 -9.5 50 0.3  
6000 20.9 69.6 230 11 5 -11.2 -6.2 23.9 75.0 -11.3 72 0.4  
5750 20.0 68.0 230 10 5 -17.2 -9.5 22.2 72.0 -13.0 95 0.5  
5500 17.8 64.0 230 10 5 -41.4 -22.7 19.4 66.9 -15.9 153 0.8  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
05/26/2018 AT 0800 MST | 05/26/2018 AT 1100 MST  
|  
K INDEX... +3.9 LI... +1.9 | K INDEX... -16.9 LI... +1.6  
CAPE... 0.0 CIN... 0.0 | CAPE... +11.2 CIN... -39.4  
|  
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 -61.2 -78.2 255 24 12 2.1 1.1 | -61.7 -79.1 250 21 11 2.0 1.1  
45000 -58.7 -73.7 260 38 20 -0.2 -0.1 | -59.3 -74.7 255 26 13 -0.1 -0.1  
40000 -58.9 -74.0 250 35 18 4.6 2.5 | -59.2 -74.6 240 43 22 5.5 3.0  
38000 -55.1 -67.2 240 33 17 6.4 3.5 | -55.0 -67.0 240 43 22 7.0 3.8  
36000 -51.2 -60.2 235 33 17 6.4 3.5 | -50.8 -59.4 235 44 23 7.0 3.8  
34000 -46.8 -52.2 230 31 16 7.8 4.3 | -46.4 -51.5 235 40 21 7.6 4.2  
32000 -42.1 -43.8 225 29 15 7.8 4.3 | -41.9 -43.4 235 34 18 7.6 4.2  
30000 -37.1 -34.8 225 27 14 8.9 4.9 | -36.8 -34.2 230 30 15 8.9 4.9  
29000 -33.7 -28.7 225 25 13 8.9 4.9 | -33.5 -28.3 225 28 14 8.9 4.9  
28000 -31.1 -24.0 225 24 12 8.7 4.8 | -30.9 -23.6 220 27 14 8.6 4.7  
27000 -28.5 -19.3 225 23 12 8.5 4.7 | -28.4 -19.1 215 26 13 8.3 4.6  
26000 -26.0 -14.8 225 21 11 8.5 4.7 | -25.9 -14.6 215 26 13 8.3 4.6  
25000 -23.4 -10.1 230 20 10 8.5 4.7 | -23.4 -10.1 210 26 13 8.3 4.5  
24000 -20.9 -5.6 230 19 10 8.7 4.8 | -20.8 -5.4 210 25 13 8.7 4.8  
23000 -18.2 -0.8 225 18 10 8.7 4.8 | -18.2 -0.8 210 25 13 8.7 4.8  
22000 -15.6 3.9 225 18 9 8.7 4.8 | -15.6 3.9 205 24 13 8.7 4.8  
21000 -13.2 8.2 220 18 9 8.2 4.5 | -13.1 8.4 205 25 13 8.3 4.6  
20000 -10.7 12.7 215 18 9 8.3 4.5 | -10.6 12.9 205 25 13 8.4 4.6  
19500 -9.5 14.9 215 18 9 8.3 4.5 | -9.4 15.1 205 25 13 8.4 4.6  
19000 -8.3 17.1 210 18 9 8.2 4.5 | -8.1 17.4 205 25 13 8.2 4.5  
18500 -7.0 19.4 210 18 9 8.2 4.5 | -6.9 19.6 205 25 13 8.2 4.5  
18000 -5.8 21.6 205 18 9 8.3 4.5 | -5.7 21.7 205 24 13 8.3 4.6  
17500 -4.6 23.7 205 18 9 8.6 4.7 | -4.4 24.1 200 24 12 9.0 4.9  
17000 -3.3 26.1 205 18 9 8.6 4.7 | -3.1 26.4 200 23 12 8.9 4.9  
16500 -2.0 28.4 205 18 9 8.3 4.6 | -1.7 28.9 200 22 11 8.8 4.8  
16000 -0.8 30.6 200 18 9 8.4 4.6 | -0.4 31.3 200 22 11 8.8 4.8  
15500 1.0 33.8 200 18 9 8.7 4.8 | 1.6 34.9 200 21 11 9.0 4.9  
15000 2.3 36.1 195 18 9 8.7 4.8 | 2.9 37.2 200 20 10 9.0 4.9  
14500 3.6 38.5 195 18 9 9.0 4.9 | 4.3 39.7 200 19 10 8.6 4.7  
14000 4.9 40.8 195 17 9 9.1 5.0 | 5.5 41.9 205 19 10 8.5 4.6  
13500 6.3 43.3 200 16 8 9.1 5.0 | 6.8 44.2 205 18 9 8.8 4.8  
13000 7.6 45.7 200 15 8 9.0 4.9 | 8.2 46.8 210 17 9 9.3 5.1  
12500 9.0 48.2 205 14 7 9.0 4.9 | 9.6 49.3 210 17 9 9.2 5.0  
12000 10.4 50.7 210 13 7 9.2 5.1 | 10.8 51.4 210 17 9 8.3 4.5  
11500 11.7 53.1 210 12 6 9.2 5.0 | 12.1 53.8 215 16 8 8.3 4.6  
11000 12.9 55.2 215 11 6 7.6 4.2 | 13.2 55.8 215 15 8 7.0 3.8  
10500 14.1 57.4 220 10 5 10.1 5.5 | 14.2 57.6 210 14 7 9.0 4.9  
10250 14.9 58.8 220 9 4 10.8 5.9 | 15.0 59.0 205 13 7 10.0 5.5  
10000 15.6 60.1 225 8 4 8.0 4.4 | 15.6 60.1 205 12 6 8.2 4.5  
9750 16.2 61.2 225 7 4 8.8 4.8 | 16.2 61.2 200 10 5 8.8 4.8  
9500 16.8 62.2 230 6 3 8.4 4.6 | 16.8 62.2 195 9 5 8.6 4.7  
9250 17.4 63.3 230 5 3 7.2 3.9 | 17.4 63.3 190 8 4 8.6 4.7  
9000 17.9 64.2 235 5 2 7.6 4.2 | 18.0 64.4 185 7 4 9.1 5.0  
8750 18.5 65.3 245 4 2 8.7 4.8 | 18.7 65.7 180 6 3 9.5 5.2  
8500 19.1 66.4 255 3 2 8.3 4.5 | 19.3 66.7 175 5 3 9.6 5.3  
8250 19.7 67.5 270 3 2 7.3 4.0 | 20.0 68.0 170 5 3 10.4 5.7  
8000 20.2 68.4 285 3 2 6.8 3.7 | 20.8 69.4 165 5 2 10.1 5.6  
7750 20.7 69.3 295 3 2 7.2 3.9 | 21.5 70.7 165 5 2 9.4 5.1  
7500 21.2 70.2 305 4 2 6.6 3.6 | 22.2 72.0 165 4 2 9.8 5.4  
7250 21.7 71.1 310 4 2 5.7 3.1 | 23.0 73.4 165 4 2 10.4 5.7  
7000 22.1 71.8 305 4 2 5.0 2.8 | 23.7 74.7 165 4 2 10.4 5.7  
6750 22.5 72.5 305 4 2 6.2 3.4 | 24.5 76.1 165 4 2 9.7 5.3  
6500 22.8 73.0 300 4 2 1.3 0.7 | 25.2 77.4 165 4 2 10.2 5.6  
6250 22.6 72.7 290 4 2 -3.6 -2.0 | 26.0 78.8 165 4 2 11.1 6.1  
6000 22.3 72.1 280 4 2 -3.5 -1.9 | 26.8 80.2 160 3 2 10.6 5.8  
5750 22.0 71.6 265 4 2 -1.9 -1.1 | 27.6 81.7 160 3 2 12.1 6.6  
5500 22.0 71.6 245 3 2 10.2 5.6 | 28.8 83.8 160 3 2 20.7 11.4  
 
05/26/2018 AT 1400 MST | 05/26/2018 AT 1700 MST  
|  
K INDEX... +3.4 LI... +0.7 | K INDEX... +9.9 LI... +0.1  
CAPE... +0.1 CIN... -0.4 | CAPE... +22.7 CIN... -19.4  
|  
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 -60.6 -77.1 250 28 14 2.3 1.2 | -60.2 -76.4 245 31 16 1.8 1.0  
45000 -57.9 -72.2 255 38 20 -0.6 -0.3 | -58.0 -72.4 245 49 25 -0.4 -0.2  
40000 -58.7 -73.7 255 57 29 5.3 2.9 | -58.4 -73.1 250 78 40 5.1 2.8  
38000 -54.5 -66.1 250 58 30 7.0 3.8 | -54.2 -65.6 245 68 35 7.1 3.9  
36000 -50.3 -58.5 245 59 31 7.0 3.8 | -49.9 -57.8 240 58 30 7.1 3.9  
34000 -45.9 -50.6 245 50 26 7.4 4.0 | -45.4 -49.7 235 46 23 7.9 4.3  
32000 -41.5 -42.7 240 36 19 7.4 4.0 | -40.6 -41.1 230 32 16 7.9 4.3  
30000 -36.0 -32.8 230 29 15 8.7 4.8 | -35.4 -31.7 220 25 13 7.6 4.2  
29000 -33.4 -28.1 225 28 15 8.7 4.8 | -33.1 -27.6 215 25 13 7.6 4.2  
28000 -30.8 -23.4 225 28 14 8.5 4.7 | -30.8 -23.4 210 25 13 7.7 4.2  
27000 -28.3 -18.9 225 27 14 8.1 4.4 | -28.5 -19.3 210 24 12 7.8 4.3  
26000 -25.9 -14.6 220 27 14 8.1 4.4 | -26.2 -15.2 205 22 12 7.8 4.3  
25000 -23.5 -10.3 220 27 14 8.1 4.4 | -23.8 -10.8 205 21 11 7.8 4.3  
24000 -21.0 -5.8 220 27 14 8.5 4.6 | -21.4 -6.5 205 22 11 8.5 4.7  
23000 -18.4 -1.1 220 28 14 8.5 4.6 | -18.8 -1.8 210 23 12 8.5 4.7  
22000 -15.9 3.4 220 28 14 8.5 4.6 | -16.3 2.7 210 25 13 8.5 4.6  
21000 -13.3 8.1 215 27 14 8.8 4.8 | -13.7 7.3 210 24 12 8.9 4.9  
20000 -10.7 12.7 210 27 14 8.8 4.8 | -11.1 12.0 205 23 12 8.9 4.9  
19500 -9.4 15.1 210 26 14 8.8 4.8 | -9.8 14.4 205 22 11 8.9 4.9  
19000 -8.1 17.4 205 26 13 8.6 4.7 | -8.4 16.9 200 22 11 9.3 5.1  
18500 -6.8 19.8 200 25 13 8.5 4.7 | -7.0 19.4 200 21 11 9.5 5.2  
18000 -5.6 21.9 200 24 12 8.6 4.7 | -5.6 21.9 200 21 11 9.5 5.2  
17500 -4.2 24.4 195 23 12 9.1 5.0 | -4.2 24.4 200 20 11 10.1 5.5  
17000 -2.9 26.8 190 22 11 9.1 5.0 | -2.7 27.1 195 20 10 10.1 5.5  
16500 -1.6 29.1 190 21 11 9.2 5.0 | -1.2 29.8 195 20 10 9.7 5.3  
16000 -0.2 31.6 185 20 10 9.2 5.0 | 1.0 33.8 190 20 10 9.6 5.2  
15500 1.8 35.2 185 19 10 9.4 5.1 | 2.4 36.3 190 20 10 9.4 5.1  
15000 3.2 37.8 180 19 10 9.4 5.2 | 3.8 38.8 185 21 11 9.4 5.1  
14500 4.6 40.3 180 19 10 9.5 5.2 | 5.2 41.4 185 21 11 9.3 5.1  
14000 6.0 42.8 180 18 9 9.5 5.2 | 6.6 43.9 185 22 11 9.3 5.1  
13500 7.5 45.5 180 17 9 9.5 5.2 | 8.0 46.4 185 23 12 9.3 5.1  
13000 8.9 48.0 175 17 9 9.4 5.2 | 9.4 48.9 180 24 12 9.7 5.3  
12500 10.2 50.4 175 16 8 9.4 5.2 | 10.8 51.4 180 25 13 9.7 5.3  
12000 11.7 53.1 175 15 8 9.5 5.2 | 12.2 54.0 180 25 13 9.3 5.1  
11500 13.1 55.6 175 14 7 9.6 5.2 | 13.6 56.5 180 26 13 9.4 5.2  
11000 14.4 57.9 175 13 7 8.8 4.8 | 14.9 58.8 180 26 14 8.2 4.5  
10500 15.7 60.3 175 12 6 11.4 6.3 | 16.1 61.0 180 26 14 9.5 5.2  
10250 16.7 62.1 180 12 6 11.9 6.6 | 16.9 62.4 180 26 14 11.0 6.1  
10000 17.4 63.3 180 12 6 8.7 4.8 | 17.7 63.9 180 26 14 10.1 5.5  
9750 18.1 64.6 180 11 6 9.6 5.2 | 18.4 65.1 180 26 13 10.0 5.5  
9500 18.8 65.8 180 11 6 9.2 5.0 | 19.2 66.6 180 26 13 10.1 5.5  
9250 19.5 67.1 180 11 6 9.9 5.4 | 19.9 67.8 180 26 13 9.8 5.4  
9000 20.3 68.5 180 11 6 10.1 5.6 | 20.6 69.1 180 26 13 9.5 5.2  
8750 21.0 69.8 180 11 5 9.8 5.4 | 21.4 70.5 180 26 13 9.8 5.4  
8500 21.7 71.1 180 10 5 9.7 5.3 | 22.1 71.8 180 26 13 9.3 5.1  
8250 22.5 72.5 185 10 5 10.7 5.8 | 22.8 73.0 180 26 13 11.0 6.0  
8000 23.3 73.9 185 10 5 10.4 5.7 | 23.7 74.7 180 25 13 10.7 5.9  
7750 24.0 75.2 185 10 5 9.3 5.1 | 24.4 75.9 180 25 13 8.9 4.9  
7500 24.7 76.5 185 10 5 9.6 5.3 | 25.0 77.0 180 25 13 9.2 5.0  
7250 25.4 77.7 185 9 5 10.4 5.7 | 25.7 78.3 180 25 13 10.0 5.5  
7000 26.3 79.3 185 9 5 10.5 5.8 | 26.5 79.7 180 25 13 10.5 5.8  
6750 27.0 80.6 190 9 5 9.5 5.2 | 27.3 81.1 180 24 13 9.7 5.3  
6500 27.7 81.9 190 9 5 9.8 5.4 | 28.0 82.4 180 24 12 9.8 5.3  
6250 28.5 83.3 190 9 4 10.7 5.9 | 28.7 83.7 180 23 12 10.6 5.8  
6000 29.3 84.7 190 8 4 11.4 6.2 | 29.6 85.3 180 22 11 11.1 6.1  
5750 30.1 86.2 190 8 4 9.6 5.3 | 30.4 86.7 180 21 11 10.2 5.6  
5500 30.9 87.6 195 7 4 14.7 8.1 | 31.1 88.0 180 19 10 10.6 5.8  
________________________________________________________________________________  
 
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 NEAR THE OLD STAPLETON  
AIRPORT SITE IN DENVER, COLORADO AT  
 
NORTH LATITUDE: 39 DEG 46 MIN 5.016 SEC  
WEST LONGITUDE: 104 DEG 52 MIN 9.984 SEC  
ELEVATION: 5285 FEET (1611 METERS)  
 
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE FRONT RANGE OF THE  
COLORADO ROCKY MOUNTAINS. 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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