893
UXUS97 KBOU 090029
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
1828 MDT MONDAY, JUNE 8, 2026
THIS FORECAST IS FOR TUESDAY, JUNE 9, 2026:
IF THE TRIGGER TEMPERATURE OF 84.1 F/28.9 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 923 FT/MIN (4.7 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 19067 FT MSL (13771 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 92.0 F/33.8 C
TIME OF TRIGGER TEMPERATURE.................... 1015 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................. 13163 FT MSL (7866 FT AGL)
THERMAL SOARING OUTLOOK FOR WEDNESDAY 06/10.... 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)................ WEAK PVA
POTENTIAL HEIGHT OF WAVE....................... 14393 FT MSL (9097 FT AGL)
WAVE SOARING OUTLOOK FOR WEDNESDAY 06/10....... FAIR
REMARKS...
SUNRISE/SUNSET.................... 05:31:06 / 20:26:32 MDT
TOTAL POSSIBLE SUNSHINE........... 14 HR 55 MIN 26 SEC (895 MIN 26 SEC)
ALTITUDE OF SUN AT 12:58:49 MDT... 73.21 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 06/09/2026 AT 0600 MDT
FREEZING LEVEL.................. 15909 FT MSL (10613 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 20254 FT MSL (14958 FT AGL)
LIFTED CONDENSATION LEVEL....... 20280 FT MSL (14983 FT AGL)
LIFTED INDEX.................... -1.9
K INDEX......................... -1.0
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 -58.7 -73.7 230 55 28 2.6 1.4 M M M M M
45000 -55.4 -67.7 225 65 34 0.4 0.2 M M M M M
40000 -54.6 -66.3 235 52 27 3.5 1.9 M M M M M
38000 -52.1 -61.8 230 46 24 4.1 2.2 M M M M M
36000 -49.7 -57.5 230 41 21 4.1 2.3 M M M M M
34000 -45.7 -50.3 225 37 19 7.9 4.4 M M M M M
32000 -40.9 -41.6 225 34 17 8.0 4.4 M M M M M
30000 -35.6 -32.1 225 32 16 7.8 4.3 38.9 102.0 4.2 M M
29000 -33.3 -27.9 225 31 16 7.8 4.3 38.2 100.8 3.7 M M
28000 -30.9 -23.6 225 30 16 7.8 4.3 37.6 99.7 3.3 M M
27000 -28.6 -19.5 225 31 16 7.8 4.3 36.7 98.1 2.7 M M
26000 -26.3 -15.3 225 32 17 7.8 4.3 36.0 96.7 2.1 M M
25000 -24.0 -11.2 230 33 17 7.7 4.2 35.3 95.6 1.6 M M
24000 -21.4 -6.5 225 33 17 9.1 5.0 34.9 94.8 1.2 M M
23000 -18.7 -1.7 225 32 16 9.1 5.0 34.6 94.4 1.0 M M
22000 -15.9 3.4 220 31 16 9.1 5.0 34.5 94.1 0.9 M M
21000 -13.3 8.1 220 31 16 8.7 4.8 34.1 93.4 0.5 M M
20000 -10.7 12.7 215 30 16 8.8 4.8 33.8 92.8 0.2 M M
19500 -9.4 15.1 215 30 16 8.8 4.8 33.6 92.5 0.1 M M
19000 -8.1 17.4 210 31 16 8.7 4.7 33.5 92.3 -0.0 1323 6.7
18500 -6.8 19.8 215 32 16 8.6 4.7 33.3 91.9 -0.2 1269 6.4
18000 -5.5 22.1 220 33 17 8.6 4.7 33.1 91.6 -0.3 1215 6.2
17500 -4.2 24.4 220 33 17 8.1 4.4 32.8 91.1 -0.6 1163 5.9
17000 -3.0 26.6 225 32 17 8.1 4.4 32.6 90.6 -0.8 1112 5.7
16500 -1.8 28.8 225 32 17 8.4 4.6 32.3 90.1 -1.0 1061 5.4
16000 -0.5 31.1 225 32 17 8.4 4.6 32.1 89.7 -1.2 1008 5.1
15500 0.7 33.3 230 33 17 8.3 4.6 31.9 89.4 -1.4 955 4.9
15000 2.5 36.5 235 34 17 8.0 4.4 31.4 88.6 -1.9 880 4.5
14500 3.7 38.7 235 35 18 7.9 4.3 31.2 88.1 -2.2 830 4.2
14000 4.8 40.6 235 35 18 7.8 4.3 30.8 87.5 -2.5 780 4.0
13500 6.0 42.8 235 35 18 7.8 4.3 30.5 86.9 -2.8 731 3.7
13000 7.1 44.8 235 33 17 7.7 4.2 30.2 86.3 -3.2 683 3.5
12500 8.2 46.8 235 31 16 8.0 4.4 29.8 85.7 -3.6 636 3.2
12000 9.5 49.1 230 28 15 9.6 5.3 29.7 85.5 -3.8 582 3.0
11500 10.9 51.6 230 26 13 9.5 5.2 29.7 85.4 -3.8 526 2.7
11000 12.2 54.0 230 25 13 8.4 4.6 29.5 85.2 -4.0 472 2.4
10500 13.4 56.1 230 25 13 11.0 6.0 29.3 84.7 -4.3 420 2.1
10250 14.4 57.9 235 24 12 11.7 6.4 29.5 85.2 -4.1 384 2.0
10000 15.1 59.2 235 23 12 8.9 4.9 29.5 85.1 -4.1 356 1.8
9750 15.8 60.4 235 22 12 9.7 5.3 29.5 85.1 -4.1 327 1.7
9500 16.5 61.7 235 22 11 9.4 5.1 29.5 85.1 -4.2 299 1.5
9250 17.1 62.8 235 22 11 7.8 4.3 29.4 84.9 -4.2 272 1.4
9000 17.7 63.9 235 21 11 8.0 4.4 29.2 84.6 -4.4 248 1.3
8750 18.4 65.1 235 21 11 9.4 5.2 29.2 84.5 -4.5 220 1.1
8500 19.0 66.2 235 21 11 9.0 4.9 29.1 84.4 -4.6 192 1.0
8250 19.7 67.5 235 21 11 8.9 4.9 29.1 84.3 -4.6 165 0.8
8000 20.3 68.5 235 22 11 8.3 4.6 29.0 84.2 -4.7 139 0.7
7750 21.0 69.8 235 22 11 8.7 4.8 28.9 84.0 -4.8 112 0.6
7500 21.6 70.9 230 23 12 6.8 3.7 28.8 83.8 -4.9 85 0.4
7250 22.0 71.6 230 23 12 2.8 1.5 28.4 83.0 -5.3 67 0.3
7000 22.0 71.6 225 24 12 0.9 0.5 27.7 81.9 -6.0 58 0.3
6750 22.1 71.8 225 24 12 4.0 2.2 27.1 80.9 -6.7 48 0.2
6500 22.2 72.0 225 24 12 -6.2 -3.4 26.5 79.8 -7.3 38 0.2
6250 21.0 69.8 220 22 12 -17.9 -9.8 24.7 76.4 -9.3 68 0.3
6000 19.6 67.3 210 21 11 -15.2 -8.3 22.7 72.9 -11.5 102 0.5
5750 18.1 64.6 205 19 10 -19.3 -10.6 20.8 69.4 -13.7 138 0.7
5500 16.1 61.0 195 15 8 -26.5 -14.5 18.3 64.9 -16.5 192 1.0
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
06/09/2026 AT 0900 MDT | 06/09/2026 AT 1200 MDT
|
CAPE... +103.2 LI... +1.4 | CAPE... +104.8 LI... -0.6
CINH... -207.1 K INDEX... +14.4 | CINH... -3.3 K INDEX... +24.8
|
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 -58.1 -72.6 230 41 21 1.7 0.9 | -58.2 -72.8 240 40 21 1.1 0.6
45000 -56.0 -68.8 235 61 31 0.1 0.0 | -56.6 -69.9 250 59 30 0.9 0.5
40000 -55.8 -68.4 235 50 26 3.5 1.9 | -55.0 -67.0 245 59 31 4.0 2.2
38000 -52.7 -62.9 235 48 25 5.0 2.8 | -52.0 -61.6 240 57 30 5.0 2.7
36000 -49.7 -57.5 235 46 24 5.0 2.8 | -49.0 -56.2 230 56 29 5.0 2.7
34000 -45.6 -50.1 235 44 23 7.9 4.3 | -44.6 -48.3 230 54 28 8.6 4.7
32000 -40.8 -41.4 230 42 22 7.9 4.3 | -38.8 -37.8 230 51 26 8.6 4.7
30000 -35.7 -32.3 225 38 20 7.4 4.0 | -34.2 -29.6 225 48 25 7.3 4.0
29000 -33.5 -28.3 220 36 19 7.4 4.0 | -32.0 -25.6 220 48 24 7.3 4.0
28000 -31.3 -24.3 215 34 18 7.6 4.2 | -29.8 -21.6 220 47 24 7.4 4.0
27000 -28.8 -19.8 215 33 17 8.5 4.7 | -27.5 -17.5 220 46 24 7.9 4.3
26000 -26.3 -15.3 215 31 16 8.5 4.7 | -25.1 -13.2 220 46 23 7.9 4.3
25000 -23.7 -10.7 215 29 15 8.5 4.7 | -22.8 -9.0 225 45 23 7.9 4.3
24000 -21.2 -6.2 215 29 15 8.6 4.7 | -20.5 -4.9 225 45 23 7.8 4.3
23000 -18.6 -1.5 220 29 15 8.6 4.7 | -18.1 -0.6 230 44 23 7.8 4.3
22000 -16.0 3.2 220 29 15 8.6 4.7 | -15.8 3.6 230 44 23 7.9 4.3
21000 -13.5 7.7 225 30 15 8.4 4.6 | -13.8 7.2 235 46 24 6.6 3.6
20000 -11.0 12.2 230 31 16 8.4 4.6 | -11.8 10.8 240 50 26 6.6 3.6
19500 -9.7 14.5 230 32 17 8.4 4.6 | -10.9 12.4 245 52 27 6.7 3.7
19000 -8.5 16.7 235 33 17 8.0 4.4 | -9.9 14.2 245 54 28 7.1 3.9
18500 -7.4 18.7 235 35 18 7.9 4.3 | -8.9 16.0 245 52 27 7.5 4.1
18000 -6.2 20.8 240 37 19 7.9 4.3 | -7.8 18.0 245 51 26 7.6 4.2
17500 -5.1 22.8 240 39 20 7.8 4.3 | -6.6 20.1 245 48 25 8.8 4.8
17000 -3.9 25.0 245 41 21 7.9 4.3 | -5.4 22.3 245 46 24 8.7 4.8
16500 -2.8 27.0 245 43 22 8.1 4.4 | -4.1 24.6 245 43 22 8.9 4.9
16000 -1.6 29.1 245 45 23 8.1 4.5 | -2.1 28.2 240 40 21 9.0 4.9
15500 0.1 32.2 245 47 24 8.9 4.9 | -0.8 30.6 240 38 20 9.2 5.1
15000 1.4 34.5 245 47 24 9.0 4.9 | 0.6 33.1 235 37 19 9.3 5.1
14500 2.7 36.9 245 47 24 8.6 4.7 | 2.0 35.6 235 35 18 9.3 5.1
14000 3.9 39.0 245 45 23 8.3 4.5 | 3.4 38.1 230 34 17 9.3 5.1
13500 5.1 41.2 245 43 22 8.5 4.6 | 4.8 40.6 225 32 17 9.4 5.1
13000 6.5 43.7 245 41 21 9.2 5.1 | 6.2 43.2 225 31 16 9.6 5.2
12500 7.8 46.0 245 39 20 9.2 5.0 | 7.6 45.7 220 31 16 9.5 5.2
12000 9.2 48.6 245 39 20 9.4 5.2 | 9.1 48.4 220 30 15 9.9 5.4
11500 10.6 51.1 250 39 20 9.5 5.2 | 10.5 50.9 220 29 15 10.0 5.5
11000 11.9 53.4 245 38 19 7.3 4.0 | 11.9 53.4 215 28 14 8.3 4.6
10500 13.0 55.4 245 34 17 10.0 5.5 | 13.1 55.6 215 27 14 10.8 5.9
10250 14.0 57.2 240 33 17 10.7 5.9 | 14.1 57.4 215 27 14 12.2 6.7
10000 14.6 58.3 240 31 16 7.8 4.3 | 14.9 58.8 215 27 14 9.8 5.4
9750 15.3 59.5 240 29 15 8.6 4.7 | 15.6 60.1 215 26 14 10.1 5.5
9500 15.9 60.6 235 28 14 8.5 4.7 | 16.4 61.5 215 26 13 10.2 5.6
9250 16.6 61.9 235 26 14 6.5 3.6 | 17.1 62.8 215 26 13 9.5 5.2
9000 17.0 62.6 230 26 13 6.8 3.7 | 17.8 64.0 215 26 13 9.4 5.1
8750 17.6 63.7 230 25 13 8.7 4.8 | 18.5 65.3 215 25 13 10.1 5.6
8500 18.3 64.9 225 25 13 8.2 4.5 | 19.3 66.7 215 25 13 9.8 5.4
8250 18.9 66.0 220 24 12 9.2 5.0 | 20.0 68.0 215 25 13 10.6 5.8
8000 19.6 67.3 220 23 12 9.0 5.0 | 20.8 69.4 215 25 13 10.2 5.6
7750 20.3 68.5 220 23 12 8.4 4.6 | 21.6 70.9 215 24 13 9.4 5.1
7500 20.9 69.6 220 23 12 7.9 4.3 | 22.3 72.1 215 24 12 9.7 5.3
7250 21.4 70.5 220 22 11 6.6 3.6 | 23.0 73.4 215 24 12 9.9 5.4
7000 21.8 71.2 220 20 10 5.4 3.0 | 23.8 74.8 215 24 12 10.1 5.6
6750 22.2 72.0 220 18 9 4.5 2.5 | 24.5 76.1 215 23 12 10.0 5.5
6500 22.3 72.1 220 17 9 -0.2 -0.1 | 25.3 77.5 215 23 12 10.6 5.8
6250 22.0 71.6 210 14 7 -4.0 -2.2 | 26.1 79.0 210 22 11 11.3 6.2
6000 21.5 70.7 205 12 6 -4.1 -2.2 | 26.9 80.4 210 21 11 11.7 6.4
5750 21.1 70.0 190 10 5 1.3 0.7 | 27.8 82.0 210 20 11 10.1 5.5
5500 21.7 71.1 180 8 4 16.7 9.2 | 28.6 83.5 210 19 10 14.0 7.7
06/09/2026 AT 1500 MDT | 06/09/2026 AT 1800 MDT
|
CAPE... +426.9 LI... -2.0 | CAPE... +171.8 LI... -0.7
CINH... -7.3 K INDEX... +28.4 | CINH... -19.8 K INDEX... +19.5
|
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 -58.6 -73.5 245 46 24 1.3 0.7 | -60.0 -76.0 255 48 25 2.0 1.1
45000 -56.3 -69.3 260 67 34 2.0 1.1 | -56.5 -69.7 255 67 34 3.2 1.7
40000 -53.3 -63.9 255 69 36 4.8 2.6 | -51.6 -60.9 240 75 39 5.9 3.3
38000 -50.2 -58.4 250 64 33 5.1 2.8 | -48.0 -54.4 240 74 38 5.9 3.3
36000 -47.1 -52.8 245 61 31 5.1 2.8 | -44.5 -48.1 240 74 38 5.9 3.3
34000 -43.2 -45.8 235 59 30 7.4 4.1 | -41.1 -42.0 235 70 36 5.5 3.0
32000 -38.2 -36.8 235 58 30 7.4 4.1 | -37.4 -35.3 235 64 33 5.5 3.0
30000 -33.7 -28.7 230 55 28 7.6 4.2 | -33.3 -27.9 230 59 30 7.4 4.1
29000 -31.4 -24.5 230 53 27 7.6 4.2 | -31.0 -23.8 230 57 29 7.4 4.1
28000 -29.1 -20.4 225 51 26 7.7 4.2 | -28.8 -19.8 225 54 28 7.5 4.1
27000 -26.8 -16.2 230 50 26 7.8 4.3 | -26.8 -16.2 230 52 27 6.5 3.6
26000 -24.5 -12.1 230 51 26 7.8 4.3 | -24.9 -12.8 230 50 26 6.6 3.6
25000 -22.2 -8.0 230 51 26 7.8 4.3 | -23.3 -9.9 235 49 25 6.7 3.7
24000 -20.1 -4.2 235 52 27 6.4 3.5 | -21.0 -5.8 240 48 25 6.6 3.6
23000 -18.3 -0.9 240 53 27 6.4 3.5 | -19.1 -2.4 245 47 24 6.6 3.6
22000 -16.4 2.5 245 55 28 6.3 3.4 | -17.1 1.2 245 47 24 6.5 3.6
21000 -14.2 6.4 250 51 26 8.0 4.4 | -14.8 5.4 245 44 22 8.8 4.8
20000 -11.9 10.6 250 43 22 8.1 4.4 | -12.2 10.0 245 39 20 8.8 4.8
19500 -10.7 12.7 255 40 20 8.2 4.5 | -10.9 12.4 245 37 19 8.8 4.9
19000 -9.6 14.7 255 36 18 8.5 4.6 | -9.6 14.7 245 35 18 9.2 5.0
18500 -8.3 17.1 255 34 18 8.8 4.8 | -8.1 17.4 245 33 17 9.6 5.3
18000 -7.0 19.4 255 32 17 8.8 4.9 | -6.7 19.9 245 32 17 9.6 5.3
17500 -5.8 21.6 255 31 16 8.7 4.8 | -5.3 22.5 245 32 16 9.8 5.4
17000 -4.5 23.9 255 30 16 8.7 4.8 | -3.8 25.2 245 31 16 9.8 5.4
16500 -3.2 26.2 255 30 15 8.8 4.8 | -1.6 29.1 240 30 15 9.6 5.3
16000 -1.3 29.7 255 30 15 8.8 4.8 | -0.2 31.6 240 29 15 9.6 5.3
15500 0.1 32.2 250 29 15 8.9 4.9 | 1.3 34.3 240 28 14 9.5 5.2
15000 1.4 34.5 250 30 15 9.0 4.9 | 2.7 36.9 240 27 14 9.4 5.2
14500 2.7 36.9 245 30 15 9.1 5.0 | 4.1 39.4 240 26 13 9.5 5.2
14000 4.1 39.4 245 30 15 9.2 5.0 | 5.5 41.9 240 25 13 9.7 5.3
13500 5.4 41.7 240 30 15 9.2 5.0 | 6.9 44.4 240 24 12 9.7 5.3
13000 6.8 44.2 240 30 16 8.8 4.9 | 8.3 46.9 240 23 12 9.1 5.0
12500 8.1 46.6 235 30 16 8.8 4.8 | 9.7 49.5 240 22 11 9.1 5.0
12000 9.4 48.9 230 31 16 9.2 5.0 | 11.1 52.0 240 21 11 9.9 5.4
11500 10.8 51.4 225 31 16 9.2 5.1 | 12.6 54.7 240 20 10 9.9 5.4
11000 12.1 53.8 225 31 16 8.4 4.6 | 14.0 57.2 245 19 10 8.8 4.8
10500 13.3 55.9 220 30 16 9.6 5.3 | 15.3 59.5 245 18 9 9.8 5.4
10250 14.1 57.4 220 30 15 11.4 6.3 | 16.1 61.0 245 18 9 11.5 6.3
10000 14.9 58.8 215 30 15 10.2 5.6 | 16.9 62.4 245 17 9 10.1 5.5
9750 15.7 60.3 215 30 15 9.5 5.2 | 17.6 63.7 245 17 9 9.3 5.1
9500 16.4 61.5 215 29 15 9.8 5.4 | 18.3 64.9 245 16 8 9.5 5.2
9250 17.1 62.8 215 29 15 9.3 5.1 | 19.0 66.2 245 15 8 9.4 5.1
9000 17.8 64.0 215 29 15 9.4 5.2 | 19.7 67.5 250 15 8 9.7 5.3
8750 18.5 65.3 215 29 15 10.2 5.6 | 20.4 68.7 250 15 7 10.0 5.5
8500 19.2 66.6 215 29 15 9.4 5.1 | 21.2 70.2 250 14 7 9.8 5.4
8250 20.0 68.0 215 28 15 12.0 6.6 | 21.9 71.4 250 14 7 10.4 5.7
8000 21.0 69.8 210 28 14 11.2 6.1 | 22.7 72.9 250 13 7 9.8 5.4
7750 21.6 70.9 210 28 14 8.1 4.4 | 23.4 74.1 255 13 6 9.0 4.9
7500 22.3 72.1 210 27 14 8.8 4.8 | 24.1 75.4 255 12 6 9.0 4.9
7250 22.9 73.2 210 27 14 10.0 5.5 | 24.8 76.6 255 12 6 9.9 5.4
7000 23.8 74.8 210 27 14 11.1 6.1 | 25.6 78.1 255 11 6 10.5 5.7
6750 24.5 76.1 210 26 14 10.2 5.6 | 26.3 79.3 260 11 6 9.2 5.1
6500 25.3 77.5 210 26 13 10.3 5.7 | 27.0 80.6 260 11 6 8.9 4.9
6250 26.1 79.0 210 25 13 10.7 5.9 | 27.6 81.7 260 10 5 10.4 5.7
6000 26.9 80.4 210 24 12 11.1 6.1 | 28.5 83.3 265 10 5 11.6 6.4
5750 27.7 81.9 210 23 12 11.0 6.1 | 29.3 84.7 265 9 5 10.1 5.5
5500 28.6 83.5 210 21 11 14.9 8.2 | 30.0 86.0 270 8 4 9.9 5.5
________________________________________________________________________________
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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