896
UXUS97 KBOU 070101
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
1900 MDT SATURDAY, JUNE 6, 2026
THIS FORECAST IS FOR SUNDAY, JUNE 7, 2026:
IF THE TRIGGER TEMPERATURE OF 82.9 F/28.3 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 1476 FT/MIN (7.5 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 20786 FT MSL (15426 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 94.0 F/34.9 C
TIME OF TRIGGER TEMPERATURE.................... 0945 MDT
TIME OF OVERDEVELOPMENT........................ 1700 MDT
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 17597 FT MSL (12236 FT AGL)
THERMAL SOARING OUTLOOK FOR MONDAY 06/08....... GOOD
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1800 MDT)......... LITTLE TO NO CHANGE
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... 7100 FT MSL (1740 FT AGL)
WEAK PVA/NVA (THROUGH 1800 MDT)................ NEITHER
POTENTIAL HEIGHT OF WAVE....................... 14469 FT MSL (9109 FT AGL)
WAVE SOARING OUTLOOK FOR MONDAY 06/08.......... POOR
REMARKS...
SUNRISE/SUNSET.................... 05:31:27 / 20:25:25 MDT
TOTAL POSSIBLE SUNSHINE........... 14 HR 53 MIN 58 SEC (893 MIN 58 SEC)
ALTITUDE OF SUN AT 12:58:26 MDT... 73.04 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 06/07/2026 AT 0600 MDT
FREEZING LEVEL.................. 15342 FT MSL (9982 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 20956 FT MSL (15596 FT AGL)
LIFTED CONDENSATION LEVEL....... 21116 FT MSL (15755 FT AGL)
LIFTED INDEX.................... -0.5
K INDEX......................... +11.8
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 -60.5 -76.9 230 20 10 1.6 0.9 M M M M M
45000 -58.1 -72.6 230 24 13 1.6 0.9 M M M M M
40000 -55.6 -68.1 245 20 11 4.3 2.3 M M M M M
38000 -51.8 -61.2 240 22 11 6.4 3.5 M M M M M
36000 -47.5 -53.5 235 23 12 6.4 3.5 M M M M M
34000 -43.1 -45.6 235 24 12 7.7 4.2 M M M M M
32000 -38.5 -37.3 235 25 13 7.7 4.2 M M M M M
30000 -33.9 -29.0 235 25 13 7.7 4.2 41.2 106.1 5.1 M M
29000 -31.6 -24.9 230 25 13 7.7 4.2 40.4 104.7 4.5 M M
28000 -29.3 -20.7 230 24 12 7.6 4.2 39.7 103.5 4.1 M M
27000 -26.9 -16.4 235 23 12 8.2 4.5 39.0 102.2 3.6 M M
26000 -24.4 -11.9 240 21 11 8.2 4.5 38.3 101.0 3.1 M M
25000 -22.0 -7.6 245 20 10 8.2 4.5 37.8 100.1 2.7 M M
24000 -19.6 -3.3 250 20 10 7.9 4.3 37.2 99.0 2.2 M M
23000 -17.2 1.0 255 19 10 7.9 4.3 36.5 97.7 1.6 M M
22000 -14.8 5.4 255 19 10 7.9 4.3 35.9 96.6 1.2 M M
21000 -12.7 9.1 250 18 9 6.5 3.6 34.9 94.9 0.4 M M
20000 -10.3 13.5 240 15 8 6.5 3.6 33.5 92.3 -0.9 1396 7.1
19500 -9.4 15.1 235 15 7 6.5 3.6 33.0 91.3 -1.4 1353 6.9
19000 -8.4 16.9 225 14 7 7.1 3.9 32.5 90.4 -1.9 1309 6.6
18500 -7.3 18.9 225 12 6 7.2 4.0 32.0 89.6 -2.3 1263 6.4
18000 -6.3 20.7 220 11 6 7.4 4.0 31.6 88.9 -2.8 1217 6.2
17500 -5.2 22.6 215 10 5 7.9 4.3 31.2 88.2 -3.1 1168 5.9
17000 -4.0 24.8 215 9 5 7.9 4.3 30.9 87.6 -3.5 1119 5.7
16500 -2.9 26.8 215 8 4 8.5 4.7 30.6 87.2 -3.8 1069 5.4
16000 -1.6 29.1 220 8 4 8.7 4.8 30.5 86.8 -4.0 1016 5.2
15500 -0.3 31.5 225 7 4 8.9 4.9 30.3 86.5 -4.2 963 4.9
15000 1.0 33.8 235 8 4 9.2 5.1 30.2 86.3 -4.3 908 4.6
14500 2.4 36.3 245 8 4 9.2 5.1 30.1 86.2 -4.4 852 4.3
14000 3.8 38.8 255 9 5 8.9 4.9 30.0 86.0 -4.6 797 4.0
13500 5.1 41.2 260 10 5 8.9 4.9 29.8 85.7 -4.7 742 3.8
13000 6.4 43.5 270 12 6 8.9 4.9 29.7 85.5 -4.9 688 3.5
12500 7.7 45.9 275 13 7 8.9 4.9 29.6 85.2 -5.0 633 3.2
12000 9.1 48.4 275 14 7 9.1 5.0 29.4 85.0 -5.2 578 2.9
11500 10.5 50.9 280 14 7 9.1 5.0 29.3 84.8 -5.3 522 2.7
11000 11.8 53.2 285 15 7 8.6 4.7 29.2 84.6 -5.4 467 2.4
10500 13.1 55.6 285 15 8 8.4 4.6 29.0 84.2 -5.7 415 2.1
10250 13.7 56.7 285 15 7 9.5 5.2 28.9 84.1 -5.7 387 2.0
10000 14.5 58.1 285 15 7 9.6 5.3 28.9 84.1 -5.8 358 1.8
9750 15.1 59.2 285 15 8 9.0 5.0 28.9 84.0 -5.8 330 1.7
9500 15.8 60.4 285 15 8 9.4 5.1 28.8 83.9 -5.9 302 1.5
9250 16.5 61.7 285 15 8 8.6 4.7 28.8 83.8 -5.9 274 1.4
9000 17.1 62.8 285 15 8 8.7 4.8 28.7 83.6 -6.1 248 1.3
8750 17.8 64.0 285 16 8 9.4 5.2 28.6 83.5 -6.1 220 1.1
8500 18.5 65.3 285 16 8 9.4 5.1 28.6 83.5 -6.2 191 1.0
8250 19.2 66.6 285 16 8 8.9 4.9 28.6 83.4 -6.2 163 0.8
8000 19.9 67.8 285 17 9 8.0 4.4 28.5 83.2 -6.3 136 0.7
7750 20.4 68.7 285 17 9 7.7 4.2 28.3 83.0 -6.5 112 0.6
7500 21.0 69.8 285 17 9 8.2 4.5 28.2 82.7 -6.6 87 0.4
7250 21.6 70.9 285 17 9 6.9 3.8 28.0 82.5 -6.8 62 0.3
7000 22.0 71.6 285 16 8 3.9 2.1 27.7 81.8 -7.2 44 0.2
6750 22.1 71.8 285 15 8 0.7 0.4 27.1 80.8 -7.8 32 0.2
6500 22.1 71.8 285 14 7 2.0 1.1 26.4 79.6 -8.6 25 0.1
6250 22.1 71.8 285 13 7 -6.0 -3.3 25.7 78.3 -9.3 18 0.1
6000 21.1 70.0 275 11 6 -14.7 -8.0 24.0 75.2 -11.1 41 0.2
5750 20.0 68.0 265 9 5 -12.9 -7.1 22.3 72.1 -12.9 66 0.3
5500 18.6 65.5 245 8 4 -24.3 -13.3 20.3 68.5 -15.1 100 0.5
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
06/07/2026 AT 0900 MDT | 06/07/2026 AT 1200 MDT
|
CAPE... 0.0 LI... +3.0 | CAPE... 0.0 LI... +2.1
CINH... -0.3 K INDEX... +6.6 | CINH... -0.0 K INDEX... +11.2
|
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 -59.7 -75.5 235 23 12 2.2 1.2 | -59.5 -75.1 230 27 14 2.6 1.4
45000 -56.9 -70.4 240 29 15 0.5 0.3 | -56.2 -69.2 240 34 17 0.5 0.2
40000 -56.1 -69.0 220 20 11 3.4 1.9 | -55.5 -67.9 225 34 18 2.7 1.5
38000 -52.2 -62.0 230 22 11 6.6 3.6 | -52.2 -62.0 230 34 17 5.7 3.1
36000 -47.7 -53.9 235 24 13 6.6 3.6 | -48.3 -54.9 235 33 17 5.7 3.1
34000 -43.4 -46.1 235 25 13 7.5 4.1 | -44.1 -47.4 240 34 18 7.6 4.2
32000 -38.9 -38.0 235 24 13 7.5 4.1 | -39.6 -39.3 245 36 19 7.6 4.2
30000 -34.3 -29.7 245 25 13 7.7 4.2 | -34.8 -30.6 245 34 17 8.3 4.5
29000 -32.0 -25.6 250 25 13 7.7 4.2 | -32.3 -26.1 245 32 16 8.3 4.5
28000 -29.7 -21.5 255 26 14 7.7 4.2 | -29.8 -21.6 245 30 15 8.4 4.6
27000 -27.3 -17.1 255 26 13 7.8 4.3 | -27.5 -17.5 250 27 14 7.9 4.3
26000 -25.0 -13.0 250 25 13 7.8 4.3 | -25.1 -13.2 250 24 13 7.9 4.3
25000 -22.7 -8.9 250 24 13 7.8 4.3 | -22.8 -9.0 255 22 11 7.9 4.3
24000 -20.3 -4.5 250 23 12 8.0 4.4 | -20.4 -4.7 255 20 10 7.8 4.3
23000 -17.9 -0.2 250 21 11 8.0 4.4 | -18.1 -0.6 255 18 9 7.8 4.3
22000 -15.5 4.1 250 20 10 8.0 4.4 | -15.7 3.7 250 17 9 7.8 4.3
21000 -13.2 8.2 245 18 9 7.5 4.1 | -12.8 9.0 250 16 8 7.9 4.3
20000 -10.4 13.3 240 16 8 7.5 4.1 | -10.5 13.1 255 16 8 7.9 4.3
19500 -9.3 15.3 240 15 8 7.5 4.1 | -9.3 15.3 255 15 8 7.9 4.4
19000 -8.2 17.2 235 14 7 7.4 4.1 | -8.1 17.4 260 15 8 7.4 4.1
18500 -7.1 19.2 230 13 7 7.5 4.1 | -7.1 19.2 260 15 8 7.3 4.0
18000 -6.0 21.2 230 13 6 7.5 4.1 | -6.0 21.2 265 14 7 7.4 4.1
17500 -4.9 23.2 225 12 6 7.9 4.4 | -4.8 23.4 260 14 7 7.8 4.3
17000 -3.7 25.3 220 11 6 7.9 4.3 | -3.7 25.3 260 13 7 7.8 4.3
16500 -2.5 27.5 220 11 5 8.3 4.6 | -2.5 27.5 260 12 6 8.3 4.5
16000 -1.3 29.7 220 10 5 8.4 4.6 | -1.3 29.7 255 11 6 8.4 4.6
15500 -0.0 32.0 220 9 5 8.6 4.7 | -0.0 32.0 255 11 6 8.4 4.6
15000 1.3 34.3 220 9 5 8.8 4.8 | 1.3 34.3 255 10 5 8.6 4.7
14500 2.6 36.7 225 8 4 8.8 4.8 | 2.5 36.5 250 9 5 8.6 4.7
14000 3.9 39.0 230 8 4 8.7 4.8 | 3.9 39.0 250 9 4 9.3 5.1
13500 5.1 41.2 240 8 4 8.8 4.8 | 5.2 41.4 250 8 4 9.2 5.0
13000 6.4 43.5 250 9 4 8.7 4.8 | 6.6 43.9 250 8 4 9.5 5.2
12500 7.7 45.9 255 9 5 8.7 4.8 | 8.0 46.4 255 8 4 9.5 5.2
12000 9.0 48.2 260 10 5 8.5 4.7 | 9.4 48.9 260 8 4 9.3 5.1
11500 10.3 50.5 270 10 5 8.5 4.7 | 10.8 51.4 265 8 4 9.3 5.1
11000 11.5 52.7 275 11 6 8.0 4.4 | 12.1 53.8 270 8 4 8.3 4.6
10500 12.7 54.9 275 12 6 8.1 4.4 | 13.3 55.9 270 8 4 8.6 4.7
10250 13.4 56.1 280 13 7 10.2 5.6 | 14.0 57.2 270 7 4 10.9 6.0
10000 14.1 57.4 280 13 7 9.5 5.2 | 14.9 58.8 270 7 4 10.6 5.8
9750 14.8 58.6 280 13 7 7.9 4.3 | 15.6 60.1 270 7 3 9.5 5.2
9500 15.4 59.7 280 13 7 8.3 4.5 | 16.3 61.3 270 7 3 9.8 5.4
9250 16.0 60.8 280 13 7 8.5 4.6 | 17.0 62.6 270 6 3 9.9 5.4
9000 16.6 61.9 280 13 7 8.5 4.7 | 17.8 64.0 265 6 3 10.0 5.5
8750 17.3 63.1 280 13 7 8.2 4.5 | 18.5 65.3 265 6 3 9.8 5.4
8500 17.9 64.2 280 14 7 8.5 4.6 | 19.3 66.7 265 6 3 9.9 5.5
8250 18.5 65.3 280 14 7 7.7 4.2 | 20.0 68.0 265 6 3 9.7 5.3
8000 19.0 66.2 280 14 7 7.5 4.1 | 20.7 69.3 270 6 3 9.8 5.4
7750 19.6 67.3 280 14 7 7.9 4.3 | 21.5 70.7 270 5 3 10.1 5.5
7500 20.2 68.4 280 14 7 8.3 4.6 | 22.2 72.0 265 5 3 10.2 5.6
7250 20.8 69.4 280 13 7 6.6 3.6 | 23.0 73.4 265 5 3 9.3 5.1
7000 21.2 70.2 275 12 6 4.9 2.7 | 23.6 74.5 270 5 3 9.0 4.9
6750 21.6 70.9 275 10 5 6.8 3.7 | 24.4 75.9 270 5 3 10.6 5.8
6500 22.1 71.8 275 9 5 7.7 4.2 | 25.2 77.4 265 5 2 11.3 6.2
6250 22.6 72.7 270 8 4 7.1 3.9 | 26.0 78.8 265 4 2 10.8 5.9
6000 23.1 73.6 265 7 3 7.1 3.9 | 26.8 80.2 265 4 2 11.1 6.1
5750 23.6 74.5 250 5 3 7.3 4.0 | 27.6 81.7 270 4 2 9.6 5.3
5500 24.3 75.7 250 5 2 12.4 6.8 | 28.5 83.3 265 4 2 15.6 8.6
06/07/2026 AT 1500 MDT | 06/07/2026 AT 1800 MDT
|
CAPE... +12.3 LI... +1.1 | CAPE... +53.5 LI... +0.9
CINH... -8.8 K INDEX... +16.8 | CINH... -20.1 K INDEX... +18.7
|
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 -58.7 -73.7 230 29 15 3.2 1.8 | -58.5 -73.3 235 35 18 3.8 2.1
45000 -54.9 -66.8 235 37 19 -0.3 -0.2 | -54.1 -65.4 240 43 22 -0.3 -0.2
40000 -55.2 -67.4 230 48 25 4.0 2.2 | -54.4 -65.9 235 52 27 3.7 2.0
38000 -52.1 -61.8 235 46 24 5.2 2.9 | -51.5 -60.7 235 52 27 4.8 2.6
36000 -48.9 -56.0 240 44 23 5.2 2.9 | -48.7 -55.7 230 51 26 4.8 2.6
34000 -44.7 -48.5 240 43 22 8.2 4.5 | -44.5 -48.1 230 47 24 8.2 4.5
32000 -39.8 -39.6 240 41 21 8.2 4.5 | -39.6 -39.3 230 40 21 8.2 4.5
30000 -34.2 -29.6 245 35 18 8.6 4.7 | -34.2 -29.6 235 35 18 7.9 4.3
29000 -31.6 -24.9 245 32 16 8.6 4.7 | -31.9 -25.4 235 34 17 7.9 4.3
28000 -29.1 -20.4 245 28 14 8.5 4.7 | -29.6 -21.3 235 32 17 7.9 4.3
27000 -26.8 -16.2 250 26 13 7.3 4.0 | -27.3 -17.1 235 30 16 7.7 4.2
26000 -24.6 -12.3 250 24 12 7.4 4.0 | -25.0 -13.0 235 28 15 7.7 4.2
25000 -22.5 -8.5 250 22 11 7.4 4.1 | -22.7 -8.9 235 26 14 7.7 4.2
24000 -20.3 -4.5 250 20 10 7.5 4.1 | -20.4 -4.7 235 25 13 8.0 4.4
23000 -18.1 -0.6 245 20 10 7.5 4.1 | -18.0 -0.4 235 24 12 8.0 4.4
22000 -15.9 3.4 235 19 10 7.5 4.1 | -15.7 3.7 235 23 12 8.0 4.4
21000 -13.6 7.5 230 17 9 7.9 4.3 | -13.3 8.1 235 22 11 7.8 4.3
20000 -11.2 11.8 230 15 8 7.9 4.3 | -11.1 12.0 240 21 11 7.8 4.3
19500 -10.1 13.8 225 13 7 7.9 4.3 | -9.9 14.2 240 20 10 7.8 4.3
19000 -8.9 16.0 225 12 6 8.0 4.4 | -8.8 16.2 240 20 10 7.9 4.3
18500 -7.7 18.1 225 12 6 8.1 4.4 | -7.6 18.3 245 19 10 8.1 4.4
18000 -5.9 21.4 225 11 6 8.1 4.4 | -5.8 21.6 245 19 10 8.3 4.5
17500 -4.7 23.5 225 11 6 8.1 4.5 | -4.5 23.9 245 19 10 8.8 4.8
17000 -3.4 25.9 225 11 6 8.1 4.4 | -3.2 26.2 245 18 9 8.8 4.8
16500 -2.2 28.0 225 11 6 8.9 4.9 | -1.9 28.6 245 18 9 9.1 5.0
16000 -0.9 30.4 220 11 6 8.9 4.9 | -0.6 30.9 245 17 9 9.1 5.0
15500 0.5 32.9 220 11 6 9.1 5.0 | 0.8 33.4 245 16 8 9.2 5.0
15000 1.8 35.2 220 10 5 9.3 5.1 | 2.2 36.0 245 16 8 9.2 5.1
14500 3.2 37.8 215 10 5 9.3 5.1 | 3.5 38.3 245 15 8 9.2 5.1
14000 4.6 40.3 215 9 5 9.4 5.2 | 4.9 40.8 245 14 7 9.2 5.0
13500 6.0 42.8 220 9 4 9.5 5.2 | 6.3 43.3 245 13 7 9.2 5.0
13000 7.4 45.3 220 8 4 8.7 4.8 | 7.7 45.9 245 13 7 9.3 5.1
12500 8.7 47.7 225 6 3 8.8 4.8 | 9.1 48.4 245 12 6 9.3 5.1
12000 10.0 50.0 230 6 3 9.5 5.2 | 10.4 50.7 250 12 6 9.2 5.0
11500 11.4 52.5 235 5 3 9.6 5.3 | 11.8 53.2 250 11 6 9.2 5.0
11000 12.8 55.0 245 4 2 9.5 5.2 | 13.1 55.6 250 10 5 8.8 4.8
10500 14.3 57.7 250 4 2 9.8 5.4 | 14.4 57.9 255 10 5 9.1 5.0
10250 15.0 59.0 250 4 2 10.5 5.8 | 15.2 59.4 255 9 5 10.2 5.6
10000 15.8 60.4 255 4 2 10.3 5.6 | 15.9 60.6 260 9 5 9.8 5.4
9750 16.5 61.7 255 4 2 9.9 5.4 | 16.6 61.9 260 9 5 9.4 5.2
9500 17.3 63.1 260 4 2 10.2 5.6 | 17.3 63.1 260 9 4 9.5 5.2
9250 18.0 64.4 260 4 2 9.2 5.1 | 18.0 64.4 265 8 4 9.5 5.2
9000 18.7 65.7 265 4 2 9.1 5.0 | 18.7 65.7 265 8 4 9.5 5.2
8750 19.4 66.9 265 5 2 10.1 5.5 | 19.4 66.9 265 8 4 9.5 5.2
8500 20.2 68.4 270 5 2 9.7 5.3 | 20.2 68.4 265 7 4 9.5 5.2
8250 20.9 69.6 270 5 3 10.3 5.7 | 20.9 69.6 270 7 4 9.5 5.2
8000 21.7 71.1 275 5 3 10.2 5.6 | 21.6 70.9 270 7 4 9.6 5.3
7750 22.4 72.3 275 5 3 9.6 5.3 | 22.3 72.1 270 7 4 9.7 5.3
7500 23.1 73.6 275 5 3 9.8 5.4 | 23.0 73.4 275 7 3 9.7 5.3
7250 23.9 75.0 280 6 3 9.6 5.2 | 23.7 74.7 275 6 3 9.8 5.4
7000 24.6 76.3 280 6 3 9.5 5.2 | 24.5 76.1 280 6 3 9.6 5.3
6750 25.3 77.5 280 6 3 9.9 5.4 | 25.2 77.4 280 6 3 9.3 5.1
6500 26.0 78.8 285 6 3 9.9 5.4 | 25.8 78.4 280 6 3 9.0 4.9
6250 26.8 80.2 285 6 3 10.4 5.7 | 26.5 79.7 285 6 3 9.7 5.3
6000 27.6 81.7 285 6 3 11.4 6.3 | 27.3 81.1 285 5 3 10.7 5.9
5750 28.4 83.1 285 6 3 10.0 5.5 | 28.1 82.6 290 5 3 9.5 5.2
5500 29.2 84.6 285 6 3 14.6 8.0 | 28.7 83.7 290 5 3 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.
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.
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