992
UXUS97 KGJT 101306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
706 AM MDT SUNDAY, MAY 10, 2026
THIS FORECAST IS FOR SUNDAY, MAY 10, 2026:
IF THE TRIGGER TEMPERATURE OF 71.7 F/22.1 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 1072 FT/MIN (5.4 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 17765 FT MSL (12157 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 84.0 F/29.3 C
TIME OF TRIGGER TEMPERATURE.................... 1100 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................. 14156 FT MSL (8547 FT AGL)
THERMAL SOARING OUTLOOK FOR MONDAY 05/11....... EXCELLENT
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 06:05:24 / 20:15:41 MDT
TOTAL POSSIBLE SUNSHINE........... 14 HR 10 MIN 16 SEC (850 MIN 16 SEC)
ALTITUDE OF SUN AT 13:10:33 MDT... 68.54 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 05/10/2026 AT 0600 MDT
FREEZING LEVEL.................. 14102 FT MSL (8494 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 21563 FT MSL (15955 FT AGL)
LIFTED CONDENSATION LEVEL....... 20753 FT MSL (15145 FT AGL)
LIFTED INDEX.................... +2.0
K INDEX......................... -8.1
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 -65.0 -85.0 290 22 11 0.5 0.3 M M M M M
45000 -63.7 -82.7 290 32 16 2.6 1.4 M M M M M
40000 -59.8 -75.6 300 31 16 4.0 2.2 M M M M M
38000 -55.2 -67.4 295 29 15 7.1 3.9 M M M M M
36000 -50.9 -59.6 295 27 14 7.1 3.9 M M M M M
34000 -46.2 -51.2 295 25 13 8.2 4.5 M M M M M
32000 -41.3 -42.3 290 23 12 8.2 4.5 M M M M M
30000 -36.3 -33.3 295 22 11 8.4 4.6 38.4 101.1 7.2 M M
29000 -33.8 -28.8 295 22 11 8.4 4.6 37.9 100.2 6.9 M M
28000 -31.3 -24.3 300 22 11 8.4 4.6 37.5 99.4 6.7 M M
27000 -28.9 -20.0 300 22 11 7.8 4.3 36.7 98.1 6.1 M M
26000 -26.6 -15.9 300 21 11 7.8 4.3 35.9 96.7 5.6 M M
25000 -24.2 -11.6 305 21 11 7.8 4.3 35.3 95.5 5.1 M M
24000 -22.0 -7.6 300 21 11 7.1 3.9 34.4 93.9 4.5 M M
23000 -19.9 -3.8 300 20 10 7.1 3.9 33.4 92.1 3.7 M M
22000 -17.8 -0.0 300 19 10 7.1 3.9 32.5 90.4 3.0 M M
21000 -15.2 4.6 300 18 9 7.1 3.9 31.2 88.2 1.9 M M
20000 -13.1 8.4 300 17 9 7.1 3.9 30.3 86.5 1.1 M M
19500 -12.0 10.4 300 17 9 7.1 3.9 29.9 85.8 0.7 M M
19000 -10.8 12.6 305 16 8 8.7 4.8 29.6 85.3 0.5 M M
18500 -9.6 14.7 305 16 8 8.5 4.7 29.4 84.9 0.3 M M
18000 -8.3 17.1 305 16 8 8.1 4.4 29.2 84.5 0.1 M M
17500 -7.1 19.2 305 15 8 7.8 4.3 28.8 83.9 -0.2 1038 5.3
17000 -5.9 21.4 305 15 8 7.7 4.2 28.5 83.3 -0.5 988 5.0
16500 -4.8 23.4 305 15 8 6.9 3.8 28.1 82.5 -0.8 940 4.8
16000 -3.7 25.3 305 14 7 7.0 3.8 27.6 81.7 -1.2 894 4.5
15500 -2.7 27.1 300 14 7 6.6 3.6 27.1 80.8 -1.7 848 4.3
15000 -1.7 28.9 300 13 7 6.6 3.6 26.6 79.8 -2.2 804 4.1
14500 -0.8 30.6 300 12 6 6.8 3.7 26.1 78.9 -2.7 760 3.9
14000 0.2 32.4 295 11 5 7.0 3.8 25.6 78.1 -3.2 715 3.6
13500 1.2 34.2 295 9 5 7.0 3.8 25.2 77.3 -3.6 670 3.4
13000 2.2 36.0 290 8 4 7.0 3.8 24.7 76.4 -4.1 625 3.2
12500 3.2 37.8 285 7 4 7.2 4.0 24.3 75.7 -4.6 581 3.0
12000 4.3 39.7 280 7 4 7.8 4.3 23.9 75.0 -5.0 533 2.7
11500 5.4 41.7 275 7 3 7.8 4.3 23.6 74.5 -5.4 485 2.5
11000 6.6 43.9 270 6 3 7.8 4.3 23.3 73.9 -5.7 436 2.2
10500 7.7 45.9 265 6 3 8.8 4.8 23.0 73.3 -6.1 386 2.0
10250 8.4 47.1 260 6 3 8.8 4.8 22.9 73.3 -6.1 358 1.8
10000 9.0 48.2 255 5 3 7.3 4.0 22.8 73.0 -6.3 333 1.7
9750 9.6 49.3 250 5 2 8.0 4.4 22.6 72.7 -6.4 308 1.6
9500 10.2 50.4 240 4 2 6.8 3.7 22.5 72.4 -6.6 282 1.4
9250 10.7 51.3 230 4 2 6.7 3.7 22.2 71.9 -6.8 261 1.3
9000 11.3 52.3 220 4 2 7.7 4.2 22.0 71.6 -7.0 237 1.2
8750 11.8 53.2 210 4 2 7.7 4.2 21.8 71.3 -7.2 213 1.1
8500 12.4 54.3 200 4 2 6.5 3.6 21.7 71.0 -7.4 189 1.0
8250 12.8 55.0 190 4 2 5.2 2.9 21.3 70.4 -7.8 168 0.9
8000 13.2 55.8 180 5 3 5.8 3.2 21.0 69.8 -8.1 148 0.8
7750 13.6 56.5 175 5 3 5.8 3.2 20.7 69.3 -8.4 128 0.7
7500 14.0 57.2 170 6 3 4.1 2.3 20.4 68.7 -8.8 109 0.6
7250 14.3 57.7 160 7 3 2.7 1.5 19.9 67.7 -9.3 95 0.5
7000 14.5 58.1 155 7 4 3.9 2.1 19.4 66.8 -9.8 80 0.4
6750 14.7 58.5 155 7 4 0.7 0.4 18.9 65.9 -10.3 65 0.3
6500 14.6 58.3 145 7 4 -4.6 -2.5 17.9 64.3 -11.3 64 0.3
6250 14.1 57.4 140 7 4 -6.3 -3.4 16.8 62.2 -12.5 69 0.4
6000 13.7 56.7 130 7 4 -2.1 -1.1 15.7 60.2 -13.6 73 0.4
5750 13.4 56.1 120 6 3 -12.7 -7.0 14.6 58.3 -14.7 76 0.4
5500 M M M M M M M M M M M M
5250 M M M M M M M M M M M M
5000 M M M M M M M M M M M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
05/10/2026 AT 0900 MDT | 05/10/2026 AT 1200 MDT
|
CAPE... 0.0 LI... +6.8 | CAPE... 0.0 LI... +6.9
CINH... -0.0 K INDEX... -8.6 | CINH... -0.2 K INDEX... -9.4
|
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 -62.4 -80.3 330 25 13 1.8 1.0 | -62.8 -81.0 330 23 12 1.3 0.7
45000 -60.0 -76.0 335 38 20 0.1 0.1 | -61.0 -77.8 345 38 19 0.6 0.3
40000 -59.7 -75.5 350 57 29 -0.6 -0.3 | -60.1 -76.2 345 55 28 -0.0 -0.0
38000 -56.1 -69.0 350 60 31 7.0 3.8 | -56.5 -69.7 345 58 30 7.0 3.8
36000 -51.9 -61.4 355 63 33 7.0 3.8 | -52.3 -62.1 350 60 31 7.0 3.8
34000 -47.7 -53.9 355 62 32 7.0 3.8 | -47.2 -53.0 350 59 30 8.1 4.5
32000 -43.5 -46.3 355 56 29 7.0 3.8 | -42.3 -44.1 350 55 28 8.1 4.5
30000 -39.3 -38.7 355 49 25 7.2 3.9 | -37.9 -36.2 350 49 25 7.0 3.8
29000 -37.2 -35.0 355 45 23 7.2 3.9 | -35.8 -32.4 350 45 23 7.0 3.8
28000 -35.0 -31.0 355 40 21 7.2 3.9 | -33.7 -28.7 350 40 21 7.0 3.8
27000 -32.7 -26.9 360 37 19 8.3 4.5 | -31.6 -24.9 350 36 19 6.9 3.8
26000 -29.6 -21.3 360 36 19 8.2 4.5 | -29.5 -21.1 350 32 17 6.9 3.8
25000 -27.2 -17.0 005 36 18 8.2 4.5 | -27.5 -17.5 345 28 15 6.9 3.8
24000 -24.7 -12.5 005 35 18 7.8 4.3 | -25.3 -13.5 350 25 13 8.1 4.5
23000 -22.4 -8.3 010 34 18 7.8 4.3 | -22.8 -9.0 355 23 12 8.1 4.4
22000 -20.1 -4.2 010 33 17 7.8 4.3 | -20.4 -4.7 005 22 11 8.1 4.4
21000 -18.0 -0.4 015 32 16 6.5 3.6 | -17.3 0.9 010 21 11 8.3 4.6
20000 -16.0 3.2 010 29 15 6.5 3.6 | -14.8 5.4 020 20 10 8.3 4.6
19500 -15.1 4.8 010 28 15 6.5 3.6 | -13.6 7.5 020 19 10 8.4 4.6
19000 -14.1 6.6 010 27 14 6.2 3.4 | -12.4 9.7 025 19 10 7.2 3.9
18500 -13.2 8.2 010 26 13 5.8 3.2 | -11.4 11.5 025 19 10 6.9 3.8
18000 -12.4 9.7 010 25 13 5.8 3.2 | -10.3 13.5 030 19 10 6.7 3.7
17500 -11.4 11.5 010 23 12 6.4 3.5 | -9.4 15.1 030 18 9 5.7 3.1
17000 -10.5 13.1 010 22 11 6.4 3.5 | -8.6 16.5 030 17 9 5.8 3.2
16500 -9.5 14.9 005 20 11 6.3 3.5 | -7.7 18.1 030 17 9 5.6 3.1
16000 -8.6 16.5 010 19 10 6.3 3.4 | -6.9 19.6 030 16 8 5.6 3.1
15500 -7.7 18.1 010 17 9 6.1 3.3 | -6.1 21.0 030 15 8 5.5 3.0
15000 -6.9 19.6 015 16 8 5.4 3.0 | -5.3 22.5 035 14 7 5.4 3.0
14500 -6.1 21.0 020 14 7 5.4 3.0 | -4.5 23.9 035 13 7 5.4 3.0
14000 -5.2 22.6 020 13 7 6.0 3.3 | -3.7 25.3 035 12 6 5.4 3.0
13500 -4.3 24.3 025 13 6 5.9 3.2 | -2.9 26.8 040 10 5 5.5 3.0
13000 -3.4 25.9 030 13 6 6.7 3.7 | -2.0 28.4 045 9 5 6.7 3.7
12500 -2.4 27.7 035 13 7 6.6 3.6 | -1.1 30.0 045 9 4 6.6 3.6
12000 -1.4 29.5 035 14 7 7.5 4.1 | -0.0 32.0 050 8 4 7.8 4.3
11500 -0.2 31.6 040 14 7 7.5 4.1 | 1.1 34.0 045 8 4 7.7 4.2
11000 0.9 33.6 040 15 8 8.0 4.4 | 2.3 36.1 045 8 4 8.1 4.4
10500 2.1 35.8 040 16 8 8.3 4.5 | 3.5 38.3 040 8 4 8.0 4.4
10250 2.7 36.9 040 16 8 6.8 3.7 | 4.0 39.2 040 8 4 7.4 4.1
10000 3.1 37.6 045 16 8 7.3 4.0 | 4.6 40.3 040 7 4 8.4 4.6
9750 3.8 38.8 045 16 8 9.2 5.0 | 5.3 41.5 035 7 4 9.5 5.2
9500 4.4 39.9 045 16 8 8.7 4.8 | 6.0 42.8 035 7 4 9.2 5.1
9250 5.1 41.2 045 16 8 8.6 4.7 | 6.6 43.9 035 7 4 9.7 5.3
9000 5.7 42.3 045 17 9 7.7 4.2 | 7.4 45.3 035 7 3 9.8 5.3
8750 6.8 44.2 045 15 8 7.0 3.8 | 8.1 46.6 030 7 3 9.7 5.3
8500 7.3 45.1 045 15 7 6.3 3.5 | 8.8 47.8 030 7 3 9.4 5.2
8250 7.7 45.9 045 14 7 6.2 3.4 | 9.5 49.1 030 6 3 8.4 4.6
8000 8.2 46.8 045 14 7 8.3 4.6 | 10.8 51.4 030 6 3 11.4 6.3
7750 8.9 48.0 045 12 6 7.5 4.1 | 11.7 53.1 030 6 3 10.3 5.6
7500 9.3 48.7 045 11 6 5.3 2.9 | 12.4 54.3 030 6 3 8.1 4.4
7250 9.7 49.5 045 11 6 5.0 2.7 | 13.0 55.4 030 6 3 8.8 4.8
7000 10.1 50.2 045 10 5 9.7 5.3 | 13.7 56.7 030 5 3 12.4 6.8
6750 10.9 51.6 040 9 4 10.1 5.6 | 14.7 58.5 030 5 3 12.1 6.7
6500 11.5 52.7 040 8 4 7.0 3.8 | 15.5 59.9 030 5 3 10.3 5.6
6250 12.0 53.6 040 8 4 6.7 3.7 | 16.3 61.3 025 5 2 9.0 4.9
6000 12.6 54.7 040 7 4 11.0 6.0 | 17.0 62.6 025 5 2 14.7 8.1
5750 13.8 56.8 035 6 3 22.7 12.5 | 18.7 65.7 025 4 2 31.3 17.2
5500 15.2 59.4 035 5 3 3.2 1.8 | 20.6 69.1 025 4 2 6.8 3.7
5250 M M M M M M M | M M M M M M M
5000 M M M M M M M | M M M M M M M
05/10/2026 AT 1500 MDT | 05/10/2026 AT 1800 MDT
|
CAPE... 0.0 LI... +4.9 | CAPE... 0.0 LI... +3.8
CINH... -0.1 K INDEX... -11.1 | CINH... -0.0 K INDEX... -9.7
|
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 -63.1 -81.6 330 25 13 1.2 0.7 | -63.9 -83.0 325 29 15 0.9 0.5
45000 -61.4 -78.5 345 39 20 0.4 0.2 | -62.4 -80.3 340 40 21 1.4 0.8
40000 -60.9 -77.6 340 52 27 -0.6 -0.3 | -60.2 -76.4 335 45 23 1.4 0.8
38000 -56.9 -70.4 345 52 27 7.6 4.2 | -56.3 -69.3 340 45 23 7.2 4.0
36000 -51.8 -61.2 345 52 27 7.6 4.2 | -51.4 -60.5 340 44 22 7.2 4.0
34000 -47.0 -52.6 345 49 25 8.3 4.6 | -46.6 -51.9 340 41 21 8.3 4.6
32000 -42.0 -43.6 345 44 23 8.3 4.6 | -41.7 -43.1 345 37 19 8.3 4.6
30000 -37.3 -35.1 345 41 21 7.5 4.1 | -36.9 -34.4 340 34 18 7.6 4.2
29000 -35.1 -31.2 345 39 20 7.5 4.1 | -34.7 -30.5 340 33 17 7.6 4.2
28000 -32.8 -27.0 345 38 19 7.6 4.1 | -32.4 -26.3 340 32 17 7.6 4.2
27000 -30.7 -23.3 345 35 18 6.9 3.8 | -30.2 -22.4 340 30 16 7.2 4.0
26000 -28.6 -19.5 345 31 16 6.9 3.8 | -28.1 -18.6 340 28 14 7.2 4.0
25000 -26.6 -15.9 350 28 14 6.9 3.8 | -25.9 -14.6 345 26 13 7.2 4.0
24000 -24.5 -12.1 350 24 12 6.9 3.8 | -23.8 -10.8 345 24 12 7.3 4.0
23000 -22.4 -8.3 345 21 11 6.9 3.8 | -21.6 -6.9 340 21 11 7.3 4.0
22000 -19.8 -3.6 340 17 9 6.9 3.8 | -18.8 -1.8 335 18 9 7.3 4.0
21000 -17.4 0.7 345 15 7 8.3 4.6 | -16.6 2.1 330 15 8 7.3 4.0
20000 -14.9 5.2 345 12 6 8.3 4.6 | -14.4 6.1 325 13 7 7.3 4.0
19500 -13.7 7.3 345 11 6 8.3 4.6 | -13.3 8.1 320 12 6 7.2 4.0
19000 -12.4 9.7 350 11 5 8.2 4.5 | -12.2 10.0 320 11 5 8.1 4.4
18500 -11.2 11.8 355 10 5 8.2 4.5 | -11.0 12.2 320 10 5 8.1 4.5
18000 -10.0 14.0 005 10 5 8.0 4.4 | -9.8 14.4 320 9 5 8.2 4.5
17500 -8.9 16.0 010 10 5 7.3 4.0 | -8.5 16.7 320 8 4 8.4 4.6
17000 -7.8 18.0 015 10 5 7.4 4.1 | -7.3 18.9 320 7 4 8.5 4.7
16500 -6.7 19.9 020 9 5 6.5 3.6 | -6.1 21.0 325 6 3 7.3 4.0
16000 -5.8 21.6 025 9 5 6.5 3.6 | -5.0 23.0 330 6 3 7.4 4.1
15500 -4.8 23.4 030 8 4 6.4 3.5 | -3.9 25.0 340 5 3 6.8 3.7
15000 -3.9 25.0 035 8 4 6.3 3.5 | -3.0 26.6 350 5 3 6.6 3.6
14500 -3.0 26.6 040 7 4 6.4 3.5 | -2.0 28.4 360 5 3 6.9 3.8
14000 -2.0 28.4 040 7 4 6.7 3.7 | -0.9 30.4 360 5 3 7.5 4.1
13500 -1.1 30.0 040 7 3 6.8 3.7 | 0.1 32.2 005 6 3 7.6 4.2
13000 0.0 32.0 035 6 3 7.6 4.2 | 1.3 34.3 005 6 3 8.5 4.6
12500 1.1 34.0 030 6 3 7.6 4.2 | 2.6 36.7 005 6 3 8.4 4.6
12000 2.3 36.1 020 6 3 8.2 4.5 | 3.8 38.8 005 6 3 8.8 4.8
11500 3.5 38.3 015 6 3 8.1 4.4 | 5.1 41.2 360 7 3 8.7 4.8
11000 4.7 40.5 010 6 3 9.0 4.9 | 6.4 43.5 360 6 3 9.0 4.9
10500 6.1 43.0 010 6 3 8.6 4.7 | 7.8 46.0 360 6 3 8.3 4.5
10250 6.7 44.1 005 6 3 7.8 4.3 | 8.3 46.9 360 6 3 7.3 4.0
10000 7.3 45.1 005 5 3 9.1 5.0 | 8.9 48.0 355 6 3 9.3 5.1
9750 8.0 46.4 360 5 3 10.1 5.5 | 9.7 49.5 355 6 3 10.4 5.7
9500 8.7 47.7 360 5 3 9.8 5.4 | 10.4 50.7 355 5 3 10.1 5.5
9250 9.5 49.1 360 5 3 10.0 5.5 | 11.2 52.2 350 5 3 9.3 5.1
9000 10.2 50.4 355 5 2 9.7 5.3 | 11.8 53.2 345 5 3 9.0 4.9
8750 10.9 51.6 355 5 2 9.5 5.2 | 12.5 54.5 340 5 3 9.4 5.2
8500 12.3 54.1 350 5 2 8.2 4.5 | 13.2 55.8 340 5 2 9.1 5.0
8250 12.9 55.2 350 4 2 9.1 5.0 | 14.4 57.9 330 4 2 8.4 4.6
8000 13.7 56.7 350 4 2 11.9 6.5 | 15.2 59.4 325 4 2 10.6 5.8
7750 14.6 58.3 350 4 2 10.5 5.8 | 15.9 60.6 330 4 2 9.8 5.4
7500 15.2 59.4 345 4 2 8.1 4.4 | 16.6 61.9 325 4 2 8.4 4.6
7250 15.8 60.4 340 4 2 8.7 4.8 | 17.2 63.0 315 4 2 8.7 4.8
7000 16.6 61.9 340 4 2 11.8 6.5 | 17.9 64.2 315 4 2 11.0 6.0
6750 17.5 63.5 345 4 2 11.8 6.5 | 18.8 65.8 320 4 2 11.1 6.1
6500 18.3 64.9 340 3 2 10.5 5.7 | 19.6 67.3 310 4 2 10.1 5.6
6250 19.1 66.4 330 3 2 9.3 5.1 | 20.3 68.5 305 4 2 9.7 5.3
6000 19.9 67.8 330 3 2 14.3 7.8 | 21.1 70.0 300 4 2 11.2 6.1
5750 21.5 70.7 330 3 2 29.3 16.1 | 22.1 71.8 305 4 2 18.2 10.0
5500 23.4 74.1 320 3 2 14.1 7.8 | 23.6 74.5 295 4 2 18.8 10.3
5250 M M M M M M M | M M M M M M M
5000 M M M M M M M | M M M M M M M
________________________________________________________________________________
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 AT WALKER FIELD IN GRAND
JUNCTION, COLORADO AT
NORTH LATITUDE: 39 DEG 07 MIN 00.001 SEC
WEST LONGITUDE: 108 DEG 31 MIN 59.998 SEC
ELEVATION: 4839 FEET (1475 METERS)
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE WESTERN SLOPE OF
COLORADO. 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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