752
UXUS97 KBOU 011233
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
0632 MDT WEDNESDAY, JULY 1, 2026
THIS FORECAST IS FOR WEDNESDAY, JULY 1, 2026:
IF THE TRIGGER TEMPERATURE OF 76.7 F/24.9 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 1397 FT/MIN (7.1 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 20532 FT MSL (15170 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 91.0 F/33.2 C
TIME OF TRIGGER TEMPERATURE.................... 0945 MDT
TIME OF OVERDEVELOPMENT........................ 2000 MDT
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 17556 FT MSL (12194 FT AGL)
THERMAL SOARING OUTLOOK FOR THURSDAY 07/02..... EXCELLENT
WAVE SOARING INDEX............................. POOR
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....................... 35063 FT MSL (29701 FT AGL)
WAVE SOARING OUTLOOK FOR THURSDAY 07/02........ POOR
REMARKS...
SUNRISE/SUNSET.................... 05:35:22 / 20:31:31 MDT
TOTAL POSSIBLE SUNSHINE........... 14 HR 56 MIN 9 SEC (896 MIN 9 SEC)
ALTITUDE OF SUN AT 13:03:26 MDT... 73.28 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 07/01/2026 AT 0600 MDT
FREEZING LEVEL.................. 14337 FT MSL (8975 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 17473 FT MSL (12111 FT AGL)
LIFTED CONDENSATION LEVEL....... 19019 FT MSL (13657 FT AGL)
LIFTED INDEX.................... -2.2
K INDEX......................... +7.0
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 -59.7 -75.5 230 44 22 2.0 1.1 M M M M M
45000 -56.4 -69.5 225 64 33 2.2 1.2 M M M M M
40000 -52.9 -63.2 215 76 39 5.3 2.9 M M M M M
38000 -49.6 -57.3 215 74 38 5.5 3.0 M M M M M
36000 -46.3 -51.3 220 71 37 5.5 3.0 M M M M M
34000 -42.4 -44.3 220 67 34 7.2 3.9 M M M M M
32000 -38.1 -36.6 225 62 32 7.2 3.9 M M M M M
30000 -33.6 -28.5 230 54 28 6.4 3.5 41.9 107.5 7.0 M M
29000 -31.7 -25.1 230 51 26 6.4 3.5 40.6 105.1 6.1 M M
28000 -29.8 -21.6 230 47 24 6.3 3.5 39.5 103.1 5.2 M M
27000 -27.6 -17.7 230 45 23 7.7 4.2 38.5 101.3 4.5 M M
26000 -25.3 -13.5 235 44 22 7.7 4.2 37.7 99.9 3.9 M M
25000 -23.0 -9.4 235 42 22 7.7 4.2 37.0 98.6 3.4 M M
24000 -20.7 -5.3 235 41 21 7.4 4.1 36.2 97.1 2.8 M M
23000 -18.5 -1.3 235 41 21 7.4 4.1 35.3 95.5 2.1 M M
22000 -16.3 2.7 235 40 20 7.5 4.1 34.5 94.1 1.4 M M
21000 -14.2 6.4 235 39 20 6.6 3.6 33.5 92.3 0.5 M M
20000 -12.3 9.9 235 38 19 6.6 3.6 32.4 90.3 -0.4 1357 6.9
19500 -11.3 11.7 235 37 19 6.6 3.6 31.9 89.3 -0.9 1313 6.7
19000 -10.3 13.5 235 37 19 6.5 3.6 31.4 88.5 -1.3 1269 6.4
18500 -9.4 15.1 235 35 18 6.3 3.5 30.8 87.4 -1.9 1226 6.2
18000 -8.0 17.6 235 33 17 6.5 3.6 29.9 85.8 -2.7 1162 5.9
17500 -7.0 19.4 240 31 16 6.9 3.8 29.4 84.9 -3.2 1118 5.7
17000 -6.0 21.2 240 30 15 6.8 3.7 28.9 84.0 -3.6 1073 5.4
16500 -4.9 23.2 245 28 15 7.5 4.1 28.4 83.2 -4.1 1027 5.2
16000 -3.8 25.2 245 26 14 7.5 4.1 28.1 82.5 -4.5 979 5.0
15500 -2.7 27.1 245 25 13 8.0 4.4 27.7 81.8 -4.8 931 4.7
15000 -1.5 29.3 250 22 11 8.3 4.6 27.4 81.4 -5.1 880 4.5
14500 -0.3 31.5 250 20 10 8.5 4.7 27.2 81.0 -5.3 828 4.2
14000 1.0 33.8 250 18 9 8.9 4.9 27.1 80.7 -5.5 775 3.9
13500 2.3 36.1 250 16 8 8.8 4.9 26.9 80.4 -5.7 721 3.7
13000 3.6 38.5 250 15 8 9.2 5.0 26.8 80.2 -5.9 666 3.4
12500 5.0 41.0 250 13 7 9.2 5.0 26.7 80.0 -6.0 611 3.1
12000 6.3 43.3 250 12 6 9.0 4.9 26.6 79.9 -6.2 556 2.8
11500 7.7 45.9 255 11 6 9.2 5.1 26.5 79.6 -6.3 501 2.5
11000 8.9 48.0 260 11 5 6.8 3.7 26.2 79.2 -6.6 450 2.3
10500 9.9 49.8 270 10 5 5.9 3.2 25.8 78.4 -7.1 405 2.1
10250 10.4 50.7 275 10 5 10.7 5.9 25.5 78.0 -7.3 383 1.9
10000 11.3 52.3 285 10 5 11.4 6.2 25.8 78.4 -7.1 347 1.8
9750 11.9 53.4 290 10 5 6.9 3.8 25.7 78.2 -7.3 323 1.6
9500 12.5 54.5 295 9 5 8.5 4.7 25.5 77.9 -7.5 298 1.5
9250 13.1 55.6 300 9 5 6.5 3.6 25.4 77.7 -7.7 274 1.4
9000 13.5 56.3 310 9 5 6.3 3.4 25.1 77.1 -8.0 254 1.3
8750 14.0 57.2 315 9 5 7.6 4.2 24.9 76.8 -8.2 231 1.2
8500 14.5 58.1 320 9 5 7.6 4.2 24.7 76.5 -8.4 207 1.1
8250 15.1 59.2 325 9 5 5.8 3.2 24.5 76.1 -8.6 184 0.9
8000 15.4 59.7 330 9 5 4.3 2.4 24.1 75.4 -9.1 167 0.8
7750 15.7 60.3 335 9 5 5.3 2.9 23.7 74.7 -9.5 149 0.8
7500 16.1 61.0 335 9 5 5.1 2.8 23.4 74.1 -9.9 131 0.7
7250 16.4 61.5 335 9 5 4.1 2.3 23.0 73.4 -10.3 114 0.6
7000 16.6 61.9 340 9 4 3.4 1.9 22.5 72.6 -10.8 100 0.5
6750 16.8 62.2 335 8 4 3.5 1.9 22.1 71.7 -11.4 86 0.4
6500 17.0 62.6 330 7 4 1.8 1.0 21.6 70.8 -12.0 75 0.4
6250 16.9 62.4 320 6 3 -0.3 -0.2 20.9 69.5 -12.8 69 0.3
6000 16.8 62.2 305 5 3 -0.1 -0.1 20.1 68.2 -13.7 65 0.3
5750 16.7 62.1 290 5 2 -0.2 -0.1 19.4 66.8 -14.6 61 0.3
5500 16.4 61.5 270 4 2 -10.8 -5.9 18.3 65.0 -15.7 64 0.3
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
07/01/2026 AT 0900 MDT | 07/01/2026 AT 1200 MDT
|
CAPE... +1.9 LI... +2.8 | CAPE... 0.0 LI... +2.3
CINH... -2.8 K INDEX... +4.1 | CINH... 0.0 K INDEX... +7.8
|
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 -59.5 -75.1 230 40 21 2.5 1.4 | -59.2 -74.6 225 41 21 2.9 1.6
45000 -55.8 -68.4 230 61 31 2.0 1.1 | -55.0 -67.0 230 56 29 2.0 1.1
40000 -52.7 -62.9 215 76 39 4.8 2.6 | -52.0 -61.6 220 69 36 4.0 2.2
38000 -49.6 -57.3 215 73 38 5.3 2.9 | -49.3 -56.7 220 66 34 4.4 2.4
36000 -46.4 -51.5 215 70 36 5.3 2.9 | -46.7 -52.1 220 63 33 4.4 2.4
34000 -42.8 -45.0 220 64 33 6.2 3.4 | -43.4 -46.1 220 58 30 6.0 3.3
32000 -38.6 -37.5 225 55 28 6.2 3.4 | -39.4 -38.9 220 50 26 6.0 3.3
30000 -34.6 -30.3 225 48 25 7.0 3.8 | -35.1 -31.2 225 44 23 7.6 4.2
29000 -32.5 -26.5 230 44 23 7.0 3.8 | -32.9 -27.2 225 42 22 7.6 4.2
28000 -30.4 -22.7 230 40 21 7.0 3.8 | -30.6 -23.1 225 40 20 7.6 4.2
27000 -28.2 -18.8 230 38 20 7.6 4.2 | -28.3 -18.9 230 38 20 7.7 4.2
26000 -25.9 -14.6 235 36 19 7.6 4.2 | -26.0 -14.8 230 37 19 7.7 4.2
25000 -23.6 -10.5 235 34 18 7.6 4.2 | -23.7 -10.7 230 36 19 7.7 4.2
24000 -21.3 -6.3 235 34 18 7.7 4.3 | -21.4 -6.5 230 35 18 7.7 4.2
23000 -19.0 -2.2 235 35 18 7.8 4.3 | -19.1 -2.4 230 35 18 7.7 4.2
22000 -16.7 1.9 235 35 18 7.8 4.3 | -16.8 1.8 230 35 18 7.8 4.3
21000 -14.5 5.9 235 35 18 7.1 3.9 | -14.6 5.7 235 34 17 7.1 3.9
20000 -12.4 9.7 235 35 18 7.2 3.9 | -12.5 9.5 235 33 17 7.2 3.9
19500 -11.3 11.7 235 35 18 7.2 3.9 | -11.4 11.5 235 32 17 7.2 3.9
19000 -10.3 13.5 235 35 18 7.1 3.9 | -10.4 13.3 235 32 16 7.2 4.0
18500 -8.7 16.3 240 34 17 7.0 3.8 | -8.8 16.2 235 31 16 7.3 4.0
18000 -7.7 18.1 240 33 17 6.9 3.8 | -7.7 18.1 235 29 15 7.5 4.1
17500 -6.7 19.9 240 32 16 6.7 3.7 | -6.6 20.1 235 28 15 7.7 4.2
17000 -5.7 21.7 240 30 16 6.6 3.6 | -5.4 22.3 235 27 14 7.7 4.2
16500 -4.7 23.5 240 29 15 7.5 4.1 | -4.3 24.3 235 26 14 7.8 4.3
16000 -3.6 25.5 245 28 14 7.4 4.1 | -3.1 26.4 235 25 13 7.8 4.3
15500 -2.5 27.5 245 26 13 7.6 4.2 | -2.0 28.4 235 24 12 8.3 4.5
15000 -1.3 29.7 250 24 12 7.7 4.2 | -0.7 30.7 230 22 12 8.4 4.6
14500 -0.2 31.6 250 22 11 7.8 4.3 | 0.5 32.9 230 21 11 8.7 4.8
14000 1.0 33.8 250 20 10 8.2 4.5 | 1.9 35.4 230 20 10 9.2 5.0
13500 2.2 36.0 250 18 9 8.2 4.5 | 3.2 37.8 230 18 9 9.1 5.0
13000 3.5 38.3 250 16 8 8.7 4.8 | 4.6 40.3 225 17 9 8.8 4.8
12500 4.7 40.5 250 15 7 8.7 4.8 | 5.9 42.6 225 15 8 8.8 4.9
12000 6.0 42.8 245 13 7 9.0 4.9 | 7.2 45.0 225 14 7 9.1 5.0
11500 7.4 45.3 245 12 6 9.0 4.9 | 8.5 47.3 225 12 6 9.2 5.0
11000 8.7 47.7 245 11 6 8.7 4.8 | 9.8 49.6 220 11 6 7.9 4.4
10500 9.9 49.8 245 10 5 9.3 5.1 | 11.0 51.8 215 10 5 10.6 5.8
10250 10.6 51.1 245 9 5 6.5 3.6 | 11.9 53.4 215 9 4 11.5 6.3
10000 11.0 51.8 245 9 5 7.1 3.9 | 12.6 54.7 210 8 4 8.6 4.7
9750 11.7 53.1 250 8 4 10.1 5.6 | 13.3 55.9 210 7 4 9.3 5.1
9500 12.4 54.3 250 7 4 9.8 5.4 | 13.9 57.0 205 6 3 9.2 5.1
9250 13.0 55.4 255 6 3 7.3 4.0 | 14.6 58.3 200 6 3 8.3 4.5
9000 13.5 56.3 260 5 3 6.9 3.8 | 15.2 59.4 195 5 3 9.1 5.0
8750 14.1 57.4 265 5 2 9.1 5.0 | 15.9 60.6 195 5 3 10.5 5.8
8500 14.8 58.6 270 4 2 8.4 4.6 | 16.7 62.1 190 4 2 10.1 5.6
8250 15.4 59.7 280 4 2 6.4 3.5 | 17.4 63.3 185 4 2 8.9 4.9
8000 15.8 60.4 285 3 1 5.1 2.8 | 18.0 64.4 180 4 2 9.2 5.1
7750 16.2 61.2 295 2 1 6.0 3.3 | 18.8 65.8 175 4 2 10.8 5.9
7500 16.6 61.9 300 2 1 5.5 3.0 | 19.6 67.3 170 3 2 10.1 5.6
7250 16.9 62.4 310 2 1 4.5 2.5 | 20.3 68.5 165 3 2 8.6 4.7
7000 17.2 63.0 315 2 1 4.6 2.6 | 20.9 69.6 165 3 2 8.8 4.8
6750 17.6 63.7 315 1 1 6.7 3.7 | 21.7 71.1 160 3 2 11.5 6.3
6500 18.1 64.6 300 1 1 8.5 4.7 | 22.6 72.7 155 3 1 11.7 6.4
6250 18.7 65.7 275 1 1 9.0 5.0 | 23.4 74.1 150 3 1 10.6 5.8
6000 19.4 66.9 250 1 1 8.5 4.6 | 24.2 75.6 145 3 1 10.2 5.6
5750 20.0 68.0 230 1 1 10.8 5.9 | 25.0 77.0 140 3 1 11.9 6.5
5500 21.1 70.0 235 1 1 18.7 10.3 | 26.2 79.2 135 2 1 22.8 12.5
07/01/2026 AT 1500 MDT | 07/01/2026 AT 1800 MDT
|
CAPE... +52.5 LI... +0.1 | CAPE... +161.3 LI... -0.2
CINH... -6.0 K INDEX... +12.8 | CINH... -18.8 K INDEX... +13.7
|
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 -59.6 -75.3 225 37 19 3.1 1.7 | -59.2 -74.6 230 34 17 3.0 1.6
45000 -54.8 -66.6 230 48 25 2.9 1.6 | -54.8 -66.6 230 46 23 2.9 1.6
40000 -50.4 -58.7 230 61 31 3.4 1.9 | -50.4 -58.7 230 60 31 3.6 2.0
38000 -48.3 -54.9 230 60 31 3.5 1.9 | -48.2 -54.8 230 58 30 3.7 2.0
36000 -46.2 -51.2 230 58 30 3.5 1.9 | -46.0 -50.8 230 57 29 3.7 2.0
34000 -42.9 -45.2 230 55 29 5.5 3.0 | -42.6 -44.7 230 54 28 5.8 3.2
32000 -39.6 -39.3 225 52 27 5.6 3.1 | -39.1 -38.4 230 50 26 5.8 3.2
30000 -35.7 -32.3 225 48 25 6.9 3.8 | -35.5 -31.9 230 44 23 6.1 3.4
29000 -33.6 -28.5 230 46 24 6.9 3.8 | -33.7 -28.7 225 40 21 6.1 3.4
28000 -31.5 -24.7 230 43 22 7.0 3.8 | -31.9 -25.4 225 37 19 6.3 3.4
27000 -29.3 -20.7 230 41 21 7.5 4.1 | -29.6 -21.3 225 34 18 7.9 4.3
26000 -27.1 -16.8 230 39 20 7.5 4.1 | -27.3 -17.1 225 33 17 7.9 4.3
25000 -24.9 -12.8 235 37 19 7.5 4.1 | -24.9 -12.8 225 31 16 7.9 4.3
24000 -22.6 -8.7 235 34 18 7.8 4.3 | -22.6 -8.7 220 29 15 8.2 4.5
23000 -20.3 -4.5 235 32 16 7.9 4.3 | -20.1 -4.2 215 27 14 8.2 4.5
22000 -17.9 -0.2 235 29 15 7.8 4.3 | -17.7 0.1 210 26 13 8.1 4.4
21000 -15.4 4.3 230 27 14 8.7 4.8 | -15.0 5.0 210 24 12 9.5 5.2
20000 -12.9 8.8 230 26 13 8.7 4.8 | -12.2 10.0 205 23 12 9.5 5.2
19500 -10.9 12.4 225 24 13 8.7 4.8 | -10.0 14.0 205 22 11 9.5 5.2
19000 -9.6 14.7 225 24 12 9.4 5.2 | -8.6 16.5 200 21 11 9.7 5.3
18500 -8.2 17.2 220 23 12 9.3 5.1 | -7.2 19.0 200 20 10 9.7 5.3
18000 -6.8 19.8 215 22 11 9.3 5.1 | -5.7 21.7 195 19 10 9.7 5.3
17500 -5.4 22.3 215 21 11 9.3 5.1 | -4.3 24.3 195 18 9 9.7 5.3
17000 -4.1 24.6 210 20 11 9.3 5.1 | -2.8 27.0 190 17 9 9.7 5.3
16500 -2.7 27.1 210 20 10 9.4 5.2 | -1.4 29.5 190 16 8 9.4 5.2
16000 -1.3 29.7 205 19 10 9.4 5.2 | 0.0 32.0 185 15 8 9.5 5.2
15500 0.1 32.2 205 17 9 9.4 5.2 | 1.4 34.5 185 14 7 9.5 5.2
15000 1.5 34.7 200 16 8 9.4 5.2 | 2.8 37.0 180 13 7 9.5 5.2
14500 2.9 37.2 200 15 8 9.4 5.1 | 4.2 39.6 180 12 6 9.5 5.2
14000 4.3 39.7 195 14 7 9.3 5.1 | 5.7 42.3 175 12 6 9.5 5.2
13500 5.7 42.3 190 13 7 9.4 5.1 | 7.1 44.8 170 11 6 9.5 5.2
13000 7.1 44.8 190 12 6 9.5 5.2 | 8.5 47.3 165 10 5 9.4 5.2
12500 8.5 47.3 185 11 6 9.5 5.2 | 9.9 49.8 160 9 5 9.4 5.2
12000 9.9 49.8 180 11 5 9.4 5.2 | 11.3 52.3 155 8 4 9.6 5.2
11500 11.3 52.3 180 10 5 9.5 5.2 | 12.7 54.9 150 8 4 9.7 5.3
11000 12.7 54.9 175 10 5 8.5 4.7 | 14.0 57.2 140 7 4 8.4 4.6
10500 13.9 57.0 165 10 5 10.8 5.9 | 15.3 59.5 125 7 4 10.2 5.6
10250 14.9 58.8 165 9 5 11.8 6.5 | 16.1 61.0 125 6 3 11.4 6.3
10000 15.6 60.1 165 9 5 9.3 5.1 | 16.9 62.4 120 6 3 9.3 5.1
9750 16.3 61.3 160 9 5 9.7 5.3 | 17.6 63.7 115 6 3 9.2 5.1
9500 17.1 62.8 160 9 5 9.7 5.3 | 18.3 64.9 110 6 3 9.4 5.1
9250 17.8 64.0 155 9 5 9.3 5.1 | 19.0 66.2 100 5 3 9.0 4.9
9000 18.5 65.3 150 9 5 9.7 5.3 | 19.6 67.3 090 6 3 9.1 5.0
8750 19.2 66.6 150 9 5 10.3 5.6 | 20.3 68.5 085 6 3 9.6 5.3
8500 20.0 68.0 150 9 5 10.2 5.6 | 21.0 69.8 080 6 3 9.5 5.2
8250 20.7 69.3 150 9 4 9.4 5.2 | 21.7 71.1 075 6 3 9.3 5.1
8000 21.4 70.5 140 9 5 9.5 5.2 | 22.4 72.3 065 7 4 9.3 5.1
7750 22.2 72.0 140 9 5 10.5 5.7 | 23.1 73.6 060 7 4 9.6 5.2
7500 22.9 73.2 140 9 5 10.1 5.5 | 23.8 74.8 060 7 3 9.6 5.2
7250 23.7 74.7 140 9 4 9.0 4.9 | 24.5 76.1 055 7 4 9.1 5.0
7000 24.3 75.7 135 9 5 9.0 4.9 | 25.2 77.4 055 8 4 9.2 5.0
6750 25.1 77.2 135 9 5 10.8 5.9 | 25.9 78.6 050 8 4 10.2 5.6
6500 25.9 78.6 135 9 4 11.2 6.1 | 26.7 80.1 050 8 4 10.5 5.7
6250 26.7 80.1 130 9 4 10.8 5.9 | 27.5 81.5 045 8 4 10.4 5.7
6000 27.5 81.5 125 9 5 11.2 6.2 | 28.3 82.9 045 8 4 10.7 5.9
5750 28.3 82.9 125 9 5 9.4 5.1 | 29.0 84.2 045 9 4 9.3 5.1
5500 29.1 84.4 125 8 4 15.7 8.6 | 29.7 85.5 040 8 4 10.9 6.0
________________________________________________________________________________
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
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page