409
UXUS97 KGJT 201306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
606 AM MST MONDAY, JANUARY 20, 2025
THIS FORECAST IS FOR MONDAY, JANUARY 20, 2025:
IF THE TRIGGER TEMPERATURE OF 25.5 F/-3.6 C IS REACHED...THEN
THERMAL SOARING INDEX....................... FAIR
MAXIMUM RATE OF LIFT........................ 315 FT/MIN (1.6 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 9334 FT MSL (4495 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 26.0 F/-3.8 C
TIME OF TRIGGER TEMPERATURE.................... 1245 MST
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................. 5178 FT MSL (338 FT AGL)
THERMAL SOARING OUTLOOK FOR TUESDAY 01/21...... FAIR
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 07:29:10 / 17:21:27 MST
TOTAL POSSIBLE SUNSHINE........... 9 HR 52 MIN 17 SEC (592 MIN 17 SEC)
ALTITUDE OF SUN AT 12:25:18 MST... 30.65 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 01/20/2025 AT 0500 MST
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C
CONVECTIVE CONDENSATION LEVEL... 10653 FT MSL (5814 FT AGL)
LIFTED CONDENSATION LEVEL....... 10268 FT MSL (5429 FT AGL)
LIFTED INDEX.................... +13.0
K INDEX......................... +0.5
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 -54.2 -65.6 300 58 30 2.9 1.6 117.6 243.6 67.8 M M
45000 -50.8 -59.4 310 65 33 -1.7 -1.0 96.8 206.3 60.2 M M
40000 -49.5 -57.1 305 75 38 -6.6 -3.6 75.5 167.9 50.6 M M
38000 -50.7 -59.3 285 73 38 1.1 0.6 64.6 148.2 44.7 M M
36000 -49.6 -57.3 290 58 30 -1.7 -0.9 57.5 135.5 41.1 M M
34000 -49.5 -57.1 305 63 33 -1.9 -1.0 49.1 120.4 36.4 M M
32000 -50.8 -59.4 290 58 30 -2.9 -1.6 38.0 100.4 29.5 M M
30000 -52.0 -61.6 290 61 31 7.5 4.1 28.2 82.7 23.1 M M
29000 -50.7 -59.3 285 56 29 -4.3 -2.3 26.0 78.7 21.8 M M
28000 -51.5 -60.7 295 61 31 3.1 1.7 21.0 69.9 18.4 M M
27000 -49.4 -56.9 295 59 30 7.1 3.9 19.9 67.8 17.7 M M
26000 -47.3 -53.1 300 59 30 7.1 3.9 18.9 66.0 17.2 M M
25000 -45.2 -49.4 300 61 31 7.2 3.9 17.9 64.3 16.7 M M
24000 -43.0 -45.4 300 58 30 7.2 3.9 17.0 62.5 16.1 M M
23000 -40.9 -41.6 305 61 31 7.9 4.3 16.0 60.8 15.5 M M
22000 -38.4 -37.1 305 53 28 7.4 4.1 15.4 59.8 15.3 M M
21000 -36.7 -34.1 310 53 27 3.6 2.0 13.9 57.0 14.2 M M
20000 -36.0 -32.8 315 46 24 -1.7 -0.9 11.2 52.2 12.1 M M
19500 -36.0 -32.8 310 45 23 2.2 1.2 9.5 49.0 10.7 M M
19000 -35.5 -31.9 310 42 21 3.9 2.1 8.3 47.0 9.8 M M
18500 -34.9 -30.8 315 38 19 4.8 2.6 7.3 45.1 9.0 M M
18000 -34.0 -29.2 315 34 18 5.7 3.1 6.6 43.8 8.5 M M
17500 -33.1 -27.6 315 33 17 6.2 3.4 5.9 42.6 8.0 M M
17000 -31.7 -25.1 305 35 18 6.2 3.4 5.0 41.0 7.2 M M
16500 -30.8 -23.4 305 35 18 5.8 3.2 4.4 39.9 6.7 M M
16000 -29.9 -21.8 305 33 17 -0.2 -0.1 3.8 38.8 6.2 M M
15500 -31.1 -24.0 305 28 14 -0.3 -0.2 0.8 33.5 3.6 M M
15000 -30.0 -22.0 305 24 13 7.2 3.9 0.3 32.6 3.2 M M
14500 -28.9 -20.0 300 21 11 7.8 4.3 -0.0 32.0 2.9 M M
14000 -27.7 -17.9 295 19 10 7.8 4.3 -0.3 31.4 2.6 M M
13500 -26.6 -15.9 310 15 8 7.9 4.3 -0.7 30.8 2.3 M M
13000 -25.3 -13.5 325 12 6 8.4 4.6 -0.9 30.4 2.1 M M
12500 -24.1 -11.4 325 13 6 8.4 4.6 -1.1 30.0 1.9 M M
12000 -22.9 -9.2 320 12 6 8.5 4.7 -1.4 29.6 1.7 M M
11500 -21.5 -6.7 330 11 6 8.6 4.7 -1.5 29.3 1.6 M M
11000 -20.4 -4.7 345 10 5 7.2 4.0 -1.8 28.7 1.3 M M
10500 -19.3 -2.7 020 9 5 7.2 4.0 -2.2 28.0 0.9 M M
10250 -18.8 -1.8 015 9 5 7.2 4.0 -2.4 27.6 0.7 M M
10000 -18.2 -0.8 005 9 5 7.2 4.0 -2.6 27.3 0.5 M M
9750 -17.7 0.1 355 9 5 7.0 3.8 -2.8 26.9 0.3 M M
9500 -17.2 1.0 350 9 5 7.3 4.0 -3.0 26.5 0.1 M M
9250 -16.6 2.1 350 8 4 7.9 4.3 -3.2 26.2 -0.0 308 1.6
9000 -16.0 3.2 345 6 3 7.9 4.3 -3.3 26.0 -0.2 283 1.4
8750 -15.5 4.1 345 6 3 7.9 4.3 -3.5 25.8 -0.3 258 1.3
8500 -14.9 5.2 345 6 3 7.9 4.3 -3.6 25.5 -0.4 233 1.2
8250 -14.3 6.3 345 6 3 7.9 4.3 -3.7 25.3 -0.6 208 1.1
8000 -13.7 7.3 360 6 3 7.9 4.3 -3.9 25.0 -0.7 183 0.9
7750 -13.1 8.4 355 6 3 7.9 4.3 -4.0 24.7 -0.9 158 0.8
7500 -12.5 9.5 360 7 4 7.9 4.3 -4.2 24.5 -1.0 133 0.7
7250 -11.9 10.6 355 7 4 7.9 4.3 -4.3 24.2 -1.2 108 0.5
7000 -11.3 11.7 355 7 4 7.9 4.3 -4.5 24.0 -1.3 83 0.4
6750 -10.7 12.7 005 7 4 7.9 4.3 -4.6 23.7 -1.5 58 0.3
6500 -10.2 13.6 010 8 4 8.0 4.4 -4.8 23.4 -1.6 33 0.2
6250 -9.6 14.7 010 7 4 7.6 4.2 -4.9 23.2 -1.8 8 0.0
6000 -9.0 15.8 355 6 3 6.9 3.8 -5.1 22.8 -2.0 M M
5750 -8.5 16.7 345 5 3 6.6 3.6 -5.3 22.4 -2.2 M M
5500 -8.0 17.6 290 3 2 6.9 3.8 -5.6 22.0 -2.4 M M
5250 -7.5 18.5 260 3 1 5.9 3.2 -5.8 21.5 -2.7 M M
5000 -7.3 18.9 230 3 2 -1.3 -0.7 -6.3 20.6 -3.2 M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
01/20/2025 AT 0800 MST | 01/20/2025 AT 1100 MST
|
CAPE... 0.0 LI... +7.2 | CAPE... +0.1 LI... +8.4
CINH... -0.1 K INDEX... -11.4 | CINH... 0.0 K INDEX... -27.4
|
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 -53.3 -63.9 300 55 28 1.7 1.0 | -54.0 -65.2 295 57 29 1.8 1.0
45000 -50.7 -59.3 310 61 32 1.7 1.0 | -51.1 -60.0 315 62 32 1.8 1.0
40000 -50.4 -58.7 305 61 31 -0.3 -0.2 | -50.9 -59.6 310 55 28 -0.3 -0.2
38000 -50.5 -58.9 305 61 31 -0.3 -0.2 | -51.1 -60.0 310 51 26 -0.3 -0.2
36000 -50.4 -58.7 305 56 29 0.4 0.2 | -50.7 -59.3 310 48 25 0.8 0.4
34000 -50.2 -58.4 305 51 26 0.4 0.2 | -50.3 -58.5 315 45 23 0.8 0.4
32000 -50.3 -58.5 310 49 25 -0.8 -0.4 | -50.0 -58.0 320 44 22 0.1 0.1
30000 -50.7 -59.3 310 49 25 -0.8 -0.4 | -49.9 -57.8 330 44 23 0.1 0.1
29000 -51.0 -59.8 310 49 25 0.4 0.2 | -49.9 -57.8 330 45 23 1.1 0.6
28000 -50.4 -58.7 310 49 25 2.1 1.2 | -49.3 -56.7 330 45 23 1.9 1.1
27000 -49.7 -57.5 310 49 25 2.1 1.2 | -48.6 -55.5 330 45 23 1.9 1.1
26000 -48.9 -56.0 315 48 25 2.9 1.6 | -48.0 -54.4 325 44 23 2.8 1.5
25000 -47.0 -52.6 315 47 24 7.2 4.0 | -46.4 -51.5 330 44 22 5.7 3.1
24000 -44.8 -48.6 320 47 24 7.2 4.0 | -44.7 -48.5 330 43 22 5.7 3.1
23000 -42.6 -44.7 320 46 24 7.0 3.8 | -43.0 -45.4 330 42 22 5.9 3.2
22000 -40.7 -41.3 325 44 23 6.4 3.5 | -41.1 -42.0 335 42 21 6.2 3.4
21000 -38.7 -37.7 325 42 22 6.4 3.5 | -39.2 -38.6 340 41 21 6.3 3.4
20000 -36.9 -34.4 330 41 21 4.6 2.5 | -37.4 -35.3 340 40 20 5.0 2.7
19500 -36.2 -33.2 330 39 20 4.7 2.6 | -36.7 -34.1 340 38 20 5.1 2.8
19000 -35.5 -31.9 330 38 19 4.7 2.6 | -35.9 -32.6 340 37 19 5.1 2.8
18500 -34.8 -30.6 330 36 19 4.7 2.6 | -35.1 -31.2 340 36 18 5.1 2.8
18000 -34.1 -29.4 330 35 18 4.8 2.6 | -34.3 -29.7 340 34 18 5.1 2.8
17500 -33.4 -28.1 330 34 17 4.4 2.4 | -33.6 -28.5 340 33 17 4.4 2.4
17000 -32.7 -26.9 330 32 17 4.5 2.4 | -33.0 -27.4 340 31 16 4.4 2.4
16500 -32.1 -25.8 330 31 16 3.8 2.1 | -32.3 -26.1 340 30 15 4.9 2.7
16000 -31.6 -24.9 330 29 15 3.7 2.0 | -31.5 -24.7 340 28 15 4.9 2.7
15500 -31.0 -23.8 330 27 14 4.0 2.2 | -30.8 -23.4 340 27 14 4.9 2.7
15000 -30.4 -22.7 325 24 12 4.2 2.3 | -30.1 -22.2 340 26 13 4.9 2.7
14500 -29.8 -21.6 325 22 11 5.0 2.8 | -29.3 -20.7 340 25 13 4.9 2.7
14000 -28.9 -20.0 325 19 10 5.8 3.2 | -28.6 -19.5 340 23 12 4.9 2.7
13500 -28.1 -18.6 320 17 9 6.5 3.6 | -27.8 -18.0 340 22 11 5.3 2.9
13000 -27.0 -16.6 320 15 8 7.3 4.0 | -27.0 -16.6 340 21 11 5.5 3.0
12500 -25.9 -14.6 325 14 7 7.6 4.2 | -26.2 -15.2 340 19 10 6.3 3.4
12000 -24.7 -12.5 330 13 7 7.8 4.3 | -25.2 -13.4 345 18 9 6.6 3.6
11500 -23.5 -10.3 335 13 7 8.0 4.4 | -24.2 -11.6 350 18 9 6.8 3.7
11000 -22.3 -8.1 340 14 7 8.0 4.4 | -23.2 -9.8 355 17 9 6.9 3.8
10500 -21.2 -6.2 345 14 7 7.8 4.3 | -22.1 -7.8 360 17 9 6.9 3.8
10250 -20.6 -5.1 345 15 8 7.6 4.2 | -21.6 -6.9 005 17 9 6.9 3.8
10000 -20.0 -4.0 350 15 8 8.0 4.4 | -21.1 -6.0 005 18 9 6.9 3.8
9750 -19.4 -2.9 350 16 8 6.3 3.5 | -20.6 -5.1 005 17 9 7.3 4.0
9500 -19.0 -2.2 350 15 8 6.7 3.7 | -20.0 -4.0 010 17 9 7.4 4.1
9250 -17.8 -0.0 360 16 8 8.5 4.7 | -19.0 -2.2 015 17 9 8.1 4.4
9000 -17.1 1.2 360 15 8 8.9 4.9 | -18.3 -0.9 015 17 9 8.8 4.8
8750 -16.5 2.3 005 15 8 7.3 4.0 | -17.7 0.1 015 17 9 7.1 3.9
8500 -16.0 3.2 005 15 8 6.7 3.7 | -17.2 1.0 015 16 8 6.6 3.6
8250 -15.5 4.1 010 14 7 7.2 3.9 | -16.7 1.9 015 16 8 7.5 4.1
8000 -15.0 5.0 010 14 7 7.2 3.9 | -16.1 3.0 015 15 8 8.0 4.4
7750 -14.4 6.1 015 13 7 7.1 3.9 | -15.5 4.1 015 14 7 8.4 4.6
7500 -13.9 7.0 015 12 6 6.4 3.5 | -14.8 5.4 015 13 7 8.8 4.8
7250 -13.5 7.7 020 12 6 5.6 3.1 | -14.2 6.4 015 13 7 8.8 4.8
7000 -13.1 8.4 025 12 6 5.6 3.1 | -13.5 7.7 015 13 7 9.2 5.1
6750 -12.6 9.3 025 11 6 6.2 3.4 | -12.8 9.0 015 12 6 10.2 5.6
6500 -12.1 10.2 025 10 5 6.9 3.8 | -12.0 10.4 015 12 6 10.7 5.9
6250 -11.6 11.1 025 9 5 7.1 3.9 | -11.2 11.8 015 12 6 10.0 5.5
6000 -11.1 12.0 030 8 4 7.0 3.8 | -10.4 13.3 015 12 6 12.5 6.9
5750 -10.6 12.9 020 6 3 7.7 4.2 | -9.2 15.4 015 10 5 20.3 11.1
5500 -9.8 14.4 020 4 2 12.6 6.9 | -7.6 18.3 015 9 5 18.2 10.0
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
01/20/2025 AT 1400 MST | 01/20/2025 AT 1700 MST
|
CAPE... 0.0 LI... +9.7 | CAPE... 0.0 LI... +10.2
CINH... -0.1 K INDEX... -34.0 | CINH... -0.0 K INDEX... -39.6
|
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 -54.8 -66.6 300 55 28 0.7 0.4 | -55.6 -68.1 310 57 29 0.5 0.3
45000 -53.8 -64.8 310 60 31 0.7 0.4 | -54.9 -66.8 315 57 29 0.5 0.3
40000 -51.8 -61.2 320 52 27 1.4 0.8 | -52.7 -62.9 330 55 29 1.6 0.9
38000 -51.0 -59.8 320 48 25 1.2 0.7 | -51.7 -61.1 340 56 29 0.5 0.3
36000 -50.6 -59.1 325 48 25 0.5 0.3 | -52.2 -62.0 350 59 30 -0.8 -0.4
34000 -50.4 -58.7 330 48 25 0.5 0.3 | -52.6 -62.7 360 63 33 -0.8 -0.4
32000 -50.0 -58.0 340 48 25 0.6 0.4 | -51.9 -61.4 005 68 35 2.7 1.5
30000 -49.6 -57.3 345 48 24 0.6 0.3 | -50.2 -58.4 010 74 38 2.7 1.5
29000 -49.4 -56.9 350 47 24 2.4 1.3 | -49.3 -56.7 015 76 39 4.7 2.6
28000 -48.5 -55.3 350 48 25 3.0 1.7 | -48.0 -54.4 015 75 39 4.5 2.4
27000 -47.6 -53.7 355 48 25 3.0 1.7 | -46.6 -51.9 015 75 39 4.5 2.4
26000 -46.6 -51.9 355 48 25 2.9 1.6 | -45.3 -49.5 015 75 39 4.5 2.5
25000 -45.2 -49.4 355 48 25 4.2 2.3 | -43.5 -46.3 015 73 37 4.9 2.7
24000 -43.9 -47.0 355 47 24 4.2 2.3 | -42.0 -43.6 015 71 37 4.9 2.7
23000 -42.7 -44.9 355 46 24 5.1 2.8 | -40.5 -40.9 015 69 35 5.1 2.8
22000 -40.9 -41.6 355 45 23 6.0 3.3 | -39.0 -38.2 015 64 33 5.1 2.8
21000 -39.0 -38.2 355 44 22 6.0 3.3 | -37.4 -35.3 015 59 30 5.2 2.8
20000 -37.2 -35.0 355 42 22 6.1 3.3 | -35.8 -32.4 010 55 28 5.7 3.1
19500 -36.3 -33.3 355 42 22 6.1 3.3 | -35.0 -31.0 010 53 27 5.7 3.1
19000 -35.4 -31.7 355 41 21 6.1 3.3 | -34.1 -29.4 010 50 26 5.7 3.1
18500 -34.5 -30.1 355 41 21 6.1 3.3 | -33.3 -27.9 010 48 25 5.7 3.1
18000 -33.6 -28.5 355 40 21 5.9 3.3 | -32.4 -26.3 010 46 24 5.6 3.1
17500 -32.7 -26.9 355 39 20 5.4 3.0 | -31.6 -24.9 005 45 23 5.4 3.0
17000 -31.9 -25.4 355 37 19 5.5 3.0 | -30.8 -23.4 005 43 22 5.4 3.0
16500 -31.1 -24.0 350 36 19 4.9 2.7 | -30.0 -22.0 005 42 22 5.1 2.8
16000 -30.4 -22.7 350 34 18 4.9 2.7 | -29.2 -20.6 005 41 21 5.2 2.8
15500 -29.7 -21.5 350 32 17 4.6 2.5 | -28.5 -19.3 360 39 20 4.6 2.5
15000 -29.0 -20.2 350 31 16 4.6 2.5 | -27.8 -18.0 360 38 19 4.7 2.6
14500 -28.3 -18.9 350 29 15 4.4 2.4 | -27.1 -16.8 360 36 19 4.4 2.4
14000 -27.7 -17.9 350 27 14 4.3 2.4 | -26.4 -15.5 360 35 18 4.4 2.4
13500 -27.0 -16.6 350 25 13 4.2 2.3 | -25.8 -14.4 360 33 17 4.3 2.4
13000 -26.4 -15.5 355 24 12 4.1 2.3 | -25.1 -13.2 360 31 16 4.3 2.3
12500 -25.8 -14.4 355 22 11 4.5 2.5 | -24.5 -12.1 360 29 15 4.6 2.5
12000 -25.1 -13.2 355 20 10 4.5 2.5 | -23.8 -10.8 360 27 14 4.6 2.5
11500 -24.3 -11.7 360 19 10 6.0 3.3 | -23.1 -9.6 005 25 13 4.9 2.7
11000 -23.4 -10.1 360 18 9 6.1 3.4 | -22.4 -8.3 005 23 12 4.8 2.6
10500 -22.4 -8.3 005 17 9 7.2 4.0 | -21.6 -6.9 010 20 10 5.9 3.2
10250 -21.9 -7.4 005 16 8 7.2 4.0 | -21.1 -6.0 010 19 10 5.5 3.0
10000 -21.3 -6.3 005 16 8 6.9 3.8 | -20.7 -5.3 010 19 10 6.3 3.5
9750 -20.8 -5.4 005 16 8 7.3 4.0 | -20.2 -4.4 010 18 9 7.0 3.9
9500 -20.2 -4.4 005 16 8 8.5 4.7 | -19.7 -3.5 010 17 9 6.2 3.4
9250 -19.6 -3.3 010 16 8 8.8 4.8 | -19.3 -2.7 010 16 8 5.3 2.9
9000 -18.9 -2.0 010 16 8 8.9 4.9 | -18.8 -1.8 015 15 8 7.4 4.0
8750 -18.3 -0.9 010 16 8 9.2 5.0 | -17.6 0.3 015 14 7 6.7 3.7
8500 -16.9 1.6 010 16 8 9.2 5.1 | -17.2 1.0 015 14 7 7.1 3.9
8250 -16.2 2.8 010 16 8 9.0 4.9 | -16.6 2.1 015 14 7 8.4 4.6
8000 -15.5 4.1 010 15 8 9.2 5.1 | -15.9 3.4 015 15 7 8.7 4.8
7750 -14.8 5.4 010 15 8 10.0 5.5 | -15.3 4.5 015 14 7 8.9 4.9
7500 -14.1 6.6 010 15 8 9.7 5.3 | -14.6 5.7 015 14 7 9.0 4.9
7250 -13.4 7.9 010 15 8 8.9 4.9 | -13.9 7.0 015 14 7 8.8 4.8
7000 -12.7 9.1 015 15 8 10.0 5.5 | -13.3 8.1 015 14 7 9.4 5.1
6750 -11.9 10.6 010 15 8 10.7 5.9 | -12.5 9.5 015 13 7 9.6 5.3
6500 -11.1 12.0 010 15 7 10.6 5.8 | -11.8 10.8 015 12 6 9.1 5.0
6250 -10.3 13.5 015 14 7 9.8 5.4 | -11.2 11.8 015 12 6 9.3 5.1
6000 -9.5 14.9 015 14 7 13.0 7.1 | -10.4 13.3 020 11 6 11.2 6.2
5750 -8.2 17.2 010 13 6 22.2 12.2 | -9.5 14.9 020 11 6 13.8 7.6
5500 -6.6 20.1 015 12 6 15.0 8.2 | -8.6 16.5 015 9 5 5.4 3.0
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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