091  
UXUS97 KBOU 221254  
SRGBOU  
 
SOARING FORECAST  
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO  
0654 MDT WEDNESDAY, MARCH 22, 2017  
 
THIS FORECAST IS FOR WEDNESDAY, MARCH 22, 2017:  
 
IF THE TRIGGER TEMPERATURE OF 70.3 F/21.3 C IS REACHED...THEN  
THERMAL SOARING INDEX....................... GOOD  
MAXIMUM RATE OF LIFT........................ 603 FT/MIN (3.1 M/S)  
MAXIMUM HEIGHT OF THERMALS.................. 14149 FT MSL (8864 FT AGL)  
 
FORECAST MAXIMUM TEMPERATURE................... 74.0 F/23.8 C  
TIME OF TRIGGER TEMPERATURE.................... 1345 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................. 8308 FT MSL (3023 FT AGL)  
THERMAL SOARING OUTLOOK FOR THURSDAY 03/23..... POOR  
 
WAVE SOARING INDEX............................. GOOD  
WAVE SOARING INDEX TREND (TO 1800 MDT)......... NO CHANGE  
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE  
WEAK PVA/NVA (THROUGH 1800 MDT)................ NEITHER  
POTENTIAL HEIGHT OF WAVE....................... 19050 FT MSL (13765 FT AGL)  
WAVE SOARING OUTLOOK FOR THURSDAY 03/23........ FAIR  
 
REMARKS...  
 
SUNRISE/SUNSET.................... 06:58:49 / 19:13:35 MDT  
TOTAL POSSIBLE SUNSHINE........... 12 HR 14 MIN 46 SEC (734 MIN 46 SEC)  
ALTITUDE OF SUN AT 13:06:12 MDT... 51.12 DEGREES  
 
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 03/22/2017 AT 0600 MDT  
 
FREEZING LEVEL.................. 12817 FT MSL (7532 FT AGL)  
CONVECTIVE CONDENSATION LEVEL... 16226 FT MSL (10941 FT AGL)  
LIFTED CONDENSATION LEVEL....... 16112 FT MSL (10827 FT AGL)  
LIFTED INDEX.................... +0.4  
K INDEX......................... +12.4  
 
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 -64.9 -84.8 270 44 23 5.0 2.7 89.4 192.9 38.0 M M  
45000 -57.6 -71.7 270 48 25 3.8 2.1 76.9 170.4 33.0 M M  
40000 -51.8 -61.2 260 63 32 1.9 1.1 62.0 143.6 25.6 M M  
38000 -51.0 -59.8 265 62 32 -6.4 -3.5 54.5 130.1 21.1 M M  
36000 -55.8 -68.4 275 69 35 5.1 2.8 38.9 102.0 10.8 M M  
34000 -52.1 -61.8 280 67 35 8.0 4.4 35.9 96.6 9.0 M M  
32000 -46.8 -52.2 275 58 30 8.9 4.9 35.0 95.0 8.6 M M  
30000 -41.3 -42.3 275 48 25 9.6 5.3 34.7 94.5 8.6 M M  
29000 -37.8 -36.0 270 47 24 8.4 4.6 34.4 93.9 8.4 M M  
28000 -35.3 -31.5 270 47 24 8.5 4.7 33.8 92.8 8.1 M M  
27000 -32.7 -26.9 265 47 24 8.5 4.7 33.3 91.9 7.8 M M  
26000 -30.2 -22.4 265 47 24 8.5 4.7 32.9 91.2 7.6 M M  
25000 -27.6 -17.7 260 47 24 8.5 4.7 32.6 90.8 7.4 M M  
24000 -25.4 -13.7 260 43 22 4.5 2.5 31.7 89.0 6.7 M M  
23000 -24.0 -11.2 260 41 21 5.0 2.7 29.9 85.7 5.3 M M  
22000 -21.9 -7.4 255 40 21 9.2 5.1 28.9 84.0 4.5 M M  
21000 -19.1 -2.4 255 39 20 9.4 5.2 28.8 83.8 4.5 M M  
20000 -16.3 2.7 255 38 20 9.5 5.2 28.7 83.7 4.5 M M  
19500 -15.0 5.0 255 39 20 7.1 3.9 28.5 83.4 4.3 M M  
19000 -14.0 6.8 255 40 20 6.3 3.4 27.9 82.2 3.8 M M  
18500 -13.2 8.2 255 40 21 5.7 3.1 27.2 81.0 3.2 M M  
18000 -12.3 9.9 255 40 20 5.7 3.1 26.5 79.7 2.5 M M  
17500 -11.5 11.3 255 40 20 5.7 3.2 25.8 78.4 1.9 M M  
17000 -10.7 12.7 255 39 20 5.8 3.2 25.1 77.2 1.3 M M  
16500 -9.8 14.4 255 39 20 6.6 3.6 24.5 76.1 0.8 M M  
16000 -8.6 16.5 255 39 20 8.7 4.8 24.3 75.7 0.6 M M  
15500 -7.3 18.9 255 39 20 8.7 4.8 24.1 75.4 0.4 M M  
15000 -6.0 21.2 255 39 20 8.7 4.8 23.9 75.1 0.2 M M  
14500 -4.1 24.6 260 39 20 8.7 4.8 23.7 74.7 0.1 M M  
14000 -2.8 27.0 260 39 20 8.7 4.8 23.6 74.5 -0.1 774 3.9  
13500 -1.5 29.3 260 38 20 8.7 4.8 23.4 74.1 -0.3 721 3.7  
13000 -0.2 31.6 265 37 19 8.7 4.8 23.2 73.8 -0.5 667 3.4  
12500 1.1 34.0 265 37 19 8.7 4.8 23.1 73.5 -0.6 614 3.1  
12000 2.4 36.3 265 35 18 8.7 4.8 22.9 73.2 -0.8 560 2.8  
11500 3.6 38.5 265 31 16 8.7 4.8 22.7 72.8 -1.0 507 2.6  
11000 4.9 40.8 265 27 14 8.7 4.8 22.5 72.5 -1.2 453 2.3  
10500 6.2 43.2 265 23 12 8.8 4.8 22.3 72.2 -1.4 400 2.0  
10250 6.9 44.4 265 20 11 8.5 4.6 22.2 72.0 -1.5 373 1.9  
10000 7.5 45.5 265 18 10 8.1 4.4 22.1 71.8 -1.6 348 1.8  
9750 8.1 46.6 265 17 9 8.1 4.4 22.0 71.5 -1.8 322 1.6  
9500 8.7 47.7 265 15 8 8.1 4.4 21.8 71.3 -1.9 297 1.5  
9250 9.3 48.7 265 13 7 8.0 4.4 21.7 71.1 -2.0 272 1.4  
9000 9.9 49.8 265 11 6 8.3 4.5 21.6 70.8 -2.1 246 1.3  
8750 10.4 50.7 250 12 6 6.2 3.4 21.4 70.5 -2.3 222 1.1  
8500 10.8 51.4 240 13 7 4.2 2.3 21.0 69.8 -2.7 204 1.0  
8250 11.1 52.0 230 15 8 5.6 3.1 20.6 69.1 -3.1 187 0.9  
8000 11.4 52.5 225 17 9 2.0 1.1 20.3 68.5 -3.5 169 0.9  
7750 11.3 52.3 225 15 8 -2.5 -1.4 19.4 67.0 -4.4 166 0.8  
7500 10.8 51.4 225 14 7 -12.5 -6.9 18.2 64.8 -5.6 173 0.9  
7250 8.9 48.0 230 13 6 -41.4 -22.7 15.5 59.9 -8.3 225 1.1  
7000 5.5 41.9 230 11 6 -28.8 -15.8 11.5 52.6 -12.4 317 1.6  
6750 4.9 40.8 235 9 5 -0.4 -0.2 10.0 50.1 -13.9 330 1.7  
6500 4.7 40.5 240 7 4 -2.5 -1.4 9.1 48.4 -14.8 328 1.7  
6250 4.5 40.1 245 6 3 -2.2 -1.2 8.2 46.8 -15.7 325 1.7  
6000 4.5 40.1 260 4 2 2.5 1.3 7.4 45.4 -16.6 320 1.6  
5750 4.9 40.8 275 4 2 7.4 4.0 7.1 44.9 -16.9 300 1.5  
5500 5.3 41.5 295 4 2 2.9 1.6 6.9 44.3 -17.3 280 1.4  
 
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *  
 
03/22/2017 AT 0900 MDT | 03/22/2017 AT 1200 MDT  
|  
CAPE... 0.0 LI... +3.1 | CAPE... 0.0 LI... +3.4  
CINH... 0.0 K INDEX... +9.5 | CINH... 0.0 K INDEX... +10.0  
|  
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 -63.2 -81.8 255 24 12 3.1 1.7 | -62.9 -81.2 255 26 13 2.5 1.4  
45000 -58.5 -73.3 255 33 17 3.2 1.7 | -59.1 -74.4 250 34 18 2.8 1.5  
40000 -53.7 -64.7 255 32 17 3.1 1.7 | -54.8 -66.6 250 33 17 2.8 1.5  
38000 -52.7 -62.9 260 32 17 1.0 0.5 | -53.4 -64.1 250 33 17 2.2 1.2  
36000 -52.1 -61.8 260 32 17 1.0 0.5 | -52.1 -61.8 245 32 16 2.2 1.2  
34000 -49.9 -57.8 260 32 16 7.2 4.0 | -49.6 -57.3 245 32 16 6.9 3.8  
32000 -45.5 -49.9 255 30 15 7.2 4.0 | -45.5 -49.9 245 31 16 6.9 3.8  
30000 -40.8 -41.4 255 28 15 8.5 4.7 | -41.0 -41.8 245 31 16 8.5 4.6  
29000 -38.3 -36.9 255 28 14 8.5 4.7 | -37.9 -36.2 245 30 16 8.5 4.6  
28000 -35.7 -32.3 255 27 14 8.5 4.7 | -35.4 -31.7 245 30 15 8.5 4.7  
27000 -33.2 -27.8 255 26 14 8.3 4.6 | -32.8 -27.0 245 29 15 8.6 4.7  
26000 -30.7 -23.3 255 25 13 8.4 4.6 | -30.2 -22.4 245 28 15 8.7 4.7  
25000 -28.2 -18.8 255 25 13 8.4 4.6 | -27.7 -17.9 245 27 14 8.7 4.8  
24000 -25.7 -14.3 255 24 12 7.8 4.3 | -25.2 -13.4 245 26 14 7.9 4.3  
23000 -23.4 -10.1 255 23 12 7.8 4.3 | -22.8 -9.0 245 25 13 7.9 4.4  
22000 -21.1 -6.0 250 22 11 7.8 4.3 | -20.4 -4.7 245 24 12 7.9 4.4  
21000 -18.8 -1.8 250 21 11 7.4 4.1 | -18.1 -0.6 245 23 12 7.7 4.2  
20000 -16.0 3.2 245 21 11 7.5 4.1 | -15.8 3.6 245 22 11 7.7 4.2  
19500 -14.9 5.2 245 21 11 7.5 4.1 | -14.7 5.5 245 22 11 7.7 4.2  
19000 -13.8 7.2 245 20 11 7.5 4.1 | -13.6 7.5 240 21 11 7.7 4.2  
18500 -12.6 9.3 245 20 11 7.4 4.1 | -12.5 9.5 240 21 11 7.0 3.8  
18000 -11.5 11.3 245 20 11 7.5 4.1 | -11.4 11.5 240 22 11 7.0 3.9  
17500 -10.4 13.3 245 20 10 7.3 4.0 | -10.4 13.3 240 22 11 7.0 3.8  
17000 -9.3 15.3 245 20 10 7.3 4.0 | -9.4 15.1 240 22 11 7.0 3.8  
16500 -8.2 17.2 240 20 10 7.5 4.1 | -8.3 17.1 240 22 11 7.0 3.8  
16000 -7.1 19.2 240 20 10 7.7 4.2 | -6.7 19.9 245 22 11 7.2 4.0  
15500 -5.9 21.4 240 19 10 7.7 4.2 | -5.7 21.7 245 21 11 7.3 4.0  
15000 -4.8 23.4 240 19 10 7.9 4.3 | -4.6 23.7 245 21 11 7.4 4.1  
14500 -3.6 25.5 240 18 9 7.8 4.3 | -3.4 25.9 245 20 10 7.4 4.1  
14000 -2.4 27.7 240 17 9 8.1 4.4 | -2.3 27.9 245 19 10 8.0 4.4  
13500 -1.2 29.8 240 16 8 8.0 4.4 | -1.1 30.0 250 18 9 7.9 4.4  
13000 -0.0 32.0 240 15 8 8.2 4.5 | 0.0 32.0 250 17 9 7.7 4.2  
12500 1.2 34.2 240 14 7 8.3 4.5 | 1.2 34.2 250 15 8 7.7 4.2  
12000 2.4 36.3 240 13 7 8.2 4.5 | 2.3 36.1 250 14 7 8.1 4.5  
11500 3.6 38.5 240 12 6 8.2 4.5 | 3.5 38.3 250 12 6 8.2 4.5  
11000 4.8 40.6 240 10 5 7.7 4.2 | 4.7 40.5 250 10 5 8.4 4.6  
10500 5.9 42.6 240 9 5 7.4 4.1 | 6.0 42.8 250 9 5 8.2 4.5  
10250 6.5 43.7 235 8 4 8.3 4.6 | 6.6 43.9 250 8 4 9.3 5.1  
10000 7.1 44.8 235 8 4 8.0 4.4 | 7.3 45.1 245 8 4 9.4 5.1  
9750 7.6 45.7 235 7 4 6.8 3.7 | 7.9 46.2 245 7 4 8.2 4.5  
9500 8.2 46.8 235 7 3 7.2 3.9 | 8.6 47.5 245 7 3 8.7 4.8  
9250 8.7 47.7 230 6 3 6.9 3.8 | 9.2 48.6 240 6 3 8.1 4.4  
9000 9.2 48.6 230 5 3 6.1 3.3 | 9.8 49.6 235 5 3 7.9 4.4  
8750 9.6 49.3 230 5 3 5.6 3.1 | 10.4 50.7 235 5 2 8.2 4.5  
8500 10.0 50.0 225 4 2 5.9 3.2 | 11.0 51.8 230 4 2 8.6 4.7  
8250 10.4 50.7 220 4 2 4.9 2.7 | 11.6 52.9 230 4 2 6.9 3.8  
8000 10.7 51.3 220 3 2 3.4 1.9 | 12.0 53.6 220 3 2 5.7 3.1  
7750 10.9 51.6 215 3 2 2.8 1.6 | 12.5 54.5 215 3 1 7.3 4.0  
7500 11.1 52.0 210 3 2 2.4 1.3 | 13.0 55.4 215 2 1 7.3 4.0  
7250 11.2 52.2 210 3 2 -0.3 -0.2 | 13.5 56.3 210 2 1 4.5 2.5  
7000 11.0 51.8 210 3 1 -2.2 -1.2 | 13.7 56.7 195 1 1 3.0 1.6  
6750 10.9 51.6 210 3 1 -1.8 -1.0 | 14.0 57.2 155 1 0 6.6 3.6  
6500 10.7 51.3 205 3 1 -2.6 -1.4 | 14.6 58.3 000 0 0 8.6 4.7  
6250 10.5 50.9 200 3 2 -3.1 -1.7 | 15.2 59.4 000 0 0 8.5 4.7  
6000 10.2 50.4 200 3 2 -3.4 -1.9 | 15.8 60.4 035 1 0 8.3 4.5  
5750 9.9 49.8 200 3 2 -2.3 -1.3 | 16.4 61.5 030 1 1 10.5 5.7  
5500 9.9 49.8 195 3 1 3.5 1.9 | 17.5 63.5 020 1 0 19.8 10.9  
 
03/22/2017 AT 1500 MDT | 03/22/2017 AT 1800 MDT  
|  
CAPE... +1.1 LI... +0.8 | CAPE... +2.7 LI... +0.2  
CINH... -2.6 K INDEX... +15.1 | CINH... -12.6 K INDEX... +15.6  
|  
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 -62.4 -80.3 255 26 13 2.8 1.5 | -62.1 -79.8 250 26 13 3.1 1.7  
45000 -58.2 -72.8 250 34 18 3.0 1.6 | -57.5 -71.5 245 34 17 2.4 1.3  
40000 -53.7 -64.7 245 35 18 3.0 1.6 | -53.8 -64.8 245 37 19 2.4 1.3  
38000 -52.6 -62.7 245 36 19 1.1 0.6 | -53.1 -63.6 245 38 19 0.4 0.2  
36000 -52.0 -61.6 245 37 19 1.1 0.6 | -52.9 -63.2 240 38 19 0.4 0.2  
34000 -49.9 -57.8 240 37 19 6.8 3.8 | -50.8 -59.4 235 37 19 7.9 4.3  
32000 -45.8 -50.4 240 36 19 6.8 3.7 | -46.1 -51.0 235 34 18 7.8 4.3  
30000 -41.2 -42.2 240 35 18 8.6 4.7 | -41.2 -42.2 235 31 16 8.7 4.8  
29000 -38.7 -37.7 240 33 17 8.6 4.7 | -38.6 -37.5 235 30 15 8.7 4.8  
28000 -36.1 -33.0 240 32 16 8.6 4.7 | -36.0 -32.8 235 29 15 8.8 4.8  
27000 -33.6 -28.5 240 31 16 8.0 4.4 | -33.4 -28.1 235 28 14 7.8 4.3  
26000 -31.2 -24.2 240 29 15 8.0 4.4 | -31.1 -24.0 235 28 14 7.9 4.4  
25000 -28.8 -19.8 240 28 14 8.0 4.4 | -28.7 -19.7 235 28 14 8.0 4.4  
24000 -26.4 -15.5 240 26 14 8.0 4.4 | -26.4 -15.5 235 27 14 7.4 4.1  
23000 -24.1 -11.4 240 25 13 8.0 4.4 | -24.2 -11.6 235 27 14 7.3 4.0  
22000 -21.7 -7.1 235 24 12 8.0 4.4 | -22.0 -7.6 235 26 14 7.3 4.0  
21000 -19.3 -2.7 235 23 12 7.5 4.1 | -19.8 -3.6 235 25 13 7.3 4.0  
20000 -16.5 2.3 235 21 11 7.6 4.2 | -17.1 1.2 230 23 12 7.3 4.0  
19500 -15.4 4.3 235 21 11 7.6 4.2 | -16.0 3.2 230 22 12 7.3 4.0  
19000 -14.3 6.3 235 20 10 7.5 4.1 | -15.0 5.0 230 22 11 7.4 4.1  
18500 -13.2 8.2 235 20 10 7.2 4.0 | -13.8 7.2 230 21 11 7.7 4.2  
18000 -12.1 10.2 235 20 10 7.2 3.9 | -12.7 9.1 230 20 10 7.6 4.2  
17500 -11.0 12.2 235 19 10 7.8 4.3 | -11.5 11.3 230 19 10 8.3 4.6  
17000 -9.8 14.4 235 19 10 7.8 4.3 | -10.2 13.6 230 19 10 8.4 4.6  
16500 -8.6 16.5 240 18 9 8.0 4.4 | -9.0 15.8 230 18 9 8.6 4.7  
16000 -7.4 18.7 240 17 9 8.2 4.5 | -7.7 18.1 230 17 9 8.8 4.8  
15500 -6.2 20.8 240 16 8 8.2 4.5 | -6.3 20.7 225 16 8 8.8 4.8  
15000 -4.9 23.2 240 15 8 8.7 4.8 | -5.0 23.0 225 15 8 8.9 4.9  
14500 -3.6 25.5 240 14 7 8.7 4.7 | -3.7 25.3 225 14 7 8.9 4.9  
14000 -2.3 27.9 240 13 7 9.2 5.1 | -2.3 27.9 225 13 7 9.3 5.1  
13500 -0.9 30.4 240 12 6 9.2 5.0 | -1.0 30.2 225 13 6 9.3 5.1  
13000 0.5 32.9 240 11 6 9.3 5.1 | 0.4 32.7 225 12 6 9.3 5.1  
12500 1.9 35.4 240 10 5 9.3 5.1 | 1.8 35.2 220 11 6 9.3 5.1  
12000 3.2 37.8 240 10 5 9.2 5.1 | 3.2 37.8 220 10 5 9.4 5.1  
11500 4.6 40.3 240 9 5 9.2 5.0 | 4.6 40.3 220 10 5 9.4 5.2  
11000 6.0 42.8 240 8 4 9.1 5.0 | 6.0 42.8 220 9 5 9.2 5.0  
10500 7.3 45.1 240 7 3 9.1 5.0 | 7.4 45.3 220 8 4 9.0 4.9  
10250 8.0 46.4 245 6 3 9.2 5.0 | 8.1 46.6 220 8 4 9.4 5.2  
10000 8.7 47.7 245 6 3 9.2 5.1 | 8.8 47.8 220 7 4 9.4 5.2  
9750 9.4 48.9 245 6 3 9.3 5.1 | 9.5 49.1 220 7 4 9.1 5.0  
9500 10.1 50.2 245 6 3 9.1 5.0 | 10.1 50.2 225 6 3 8.7 4.8  
9250 10.8 51.4 250 5 3 9.7 5.3 | 10.8 51.4 225 6 3 10.8 6.0  
9000 11.5 52.7 255 4 2 9.6 5.3 | 11.7 53.1 220 6 3 10.4 5.7  
8750 12.2 54.0 260 4 2 8.8 4.8 | 12.3 54.1 225 5 3 7.9 4.3  
8500 12.8 55.0 260 4 2 9.1 5.0 | 12.9 55.2 230 5 3 8.4 4.6  
8250 13.5 56.3 265 4 2 8.7 4.7 | 13.5 56.3 230 5 2 8.9 4.9  
8000 14.1 57.4 275 3 2 9.0 4.9 | 14.2 57.6 230 5 2 9.6 5.3  
7750 14.8 58.6 280 3 2 9.9 5.4 | 14.9 58.8 235 4 2 9.2 5.1  
7500 15.6 60.1 275 3 2 10.1 5.5 | 15.6 60.1 240 4 2 9.0 4.9  
7250 16.3 61.3 275 3 2 9.6 5.3 | 16.3 61.3 245 4 2 9.5 5.2  
7000 17.0 62.6 285 3 2 9.4 5.2 | 17.0 62.6 245 4 2 9.9 5.4  
6750 17.8 64.0 290 3 1 10.4 5.7 | 17.7 63.9 245 4 2 9.5 5.2  
6500 18.6 65.5 285 3 2 10.8 5.9 | 18.4 65.1 255 3 2 9.4 5.2  
6250 19.4 66.9 285 3 2 10.4 5.7 | 19.2 66.6 260 3 2 10.2 5.6  
6000 20.1 68.2 295 3 1 10.8 5.9 | 20.0 68.0 260 3 2 10.9 6.0  
5750 20.9 69.6 305 3 1 9.1 5.0 | 20.7 69.3 260 3 1 9.1 5.0  
5500 21.7 71.1 290 3 1 13.3 7.3 | 21.3 70.3 270 3 1 6.0 3.3  
________________________________________________________________________________  
 
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.  
 
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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