Soaring Guidance
Issued by NWS Denver/Boulder, CO
Issued by NWS Denver/Boulder, CO
690
UXUS97 KBOU 010120
SRGBOU
Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1920 MDT Sunday, June 30, 2024
This forecast is for Monday, July 1, 2024:
If the trigger temperature of 83.8 F/28.8 C is reached...then
Thermal Soaring Index....................... Excellent
Maximum rate of lift........................ 939 ft/min (4.8 m/s)
Maximum height of thermals.................. 15649 ft MSL (10382 ft AGL)
Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10191 ft MSL (4924 ft AGL)
Thermal soaring outlook for Tuesday 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)................ Weak PVA
Potential height of wave....................... 22490 ft MSL (17223 ft AGL)
Wave soaring outlook for Tuesday 07/02......... Poor
Remarks...
Sunrise/Sunset.................... 05:35:36 / 20:31:27 MDT
Total possible sunshine........... 14 hr 55 min 51 sec (895 min 51 sec)
Altitude of sun at 13:03:32 MDT... 73.24 degrees
Upper air data from numerical model forecast valid on 07/01/2024 at 0600 MDT
Freezing level.................. 16248 ft MSL (10981 ft AGL)
Convective condensation level... 14371 ft MSL (9104 ft AGL)
Lifted condensation level....... 14719 ft MSL (9452 ft AGL)
Lifted index.................... -2.3
K index......................... +30.0
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 -64.1 -83.4 240 34 17 1.9 1.0 M M M M M
45000 -58.1 -72.6 240 47 24 6.7 3.7 M M M M M
40000 -48.0 -54.4 235 52 27 6.6 3.6 M M M M M
38000 -44.1 -47.4 235 52 27 6.6 3.6 M M M M M
36000 -40.1 -40.2 230 52 27 7.3 4.0 M M M M M
34000 -35.4 -31.7 230 48 25 7.8 4.3 M M M M M
32000 -30.7 -23.3 230 43 22 9.0 4.9 M M M M M
30000 -26.4 -15.5 235 40 20 7.1 3.9 50.7 123.2 13.9 M M
29000 -23.8 -10.8 235 38 19 7.1 3.9 49.5 121.0 13.1 M M
28000 -21.7 -7.1 240 36 19 7.1 3.9 48.5 119.3 12.5 M M
27000 -19.6 -3.3 235 36 18 7.1 3.9 47.4 117.3 11.7 M M
26000 -17.5 0.5 235 35 18 7.2 3.9 46.5 115.6 11.1 M M
25000 -15.4 4.3 230 35 18 6.4 3.5 45.6 114.1 10.5 M M
24000 -13.7 7.3 225 36 19 5.8 3.2 44.0 111.2 9.2 M M
23000 -12.0 10.4 220 37 19 5.8 3.2 42.6 108.6 8.1 M M
22000 -10.4 13.3 215 39 20 5.7 3.1 41.3 106.3 7.0 M M
21000 -8.7 16.3 215 35 18 5.7 3.1 39.7 103.5 5.8 M M
20000 -7.0 19.4 215 32 16 5.7 3.1 38.3 100.9 4.6 M M
19500 -6.2 20.8 215 30 15 5.7 3.1 37.6 99.8 4.0 M M
19000 -5.3 22.5 215 28 15 6.4 3.5 37.0 98.6 3.5 M M
18500 -4.4 24.1 220 27 14 6.4 3.5 36.4 97.6 2.9 M M
18000 -3.5 25.7 225 26 13 6.4 3.5 35.9 96.6 2.4 M M
17500 -2.5 27.5 225 26 13 6.4 3.5 35.3 95.5 1.9 M M
17000 -1.6 29.1 230 25 13 6.4 3.5 34.7 94.5 1.4 M M
16500 -0.7 30.7 235 24 12 6.9 3.8 34.2 93.6 0.9 M M
16000 0.3 32.5 235 23 12 6.8 3.7 33.7 92.7 0.4 M M
15500 1.3 34.3 240 22 11 7.8 4.3 33.3 91.9 -0.0 935 4.7
15000 2.5 36.5 240 20 10 8.2 4.5 33.0 91.4 -0.3 885 4.5
14500 3.7 38.7 240 18 9 8.4 4.6 32.8 91.0 -0.6 835 4.2
14000 5.6 42.1 240 16 8 8.8 4.8 32.5 90.5 -0.9 755 3.8
13500 6.9 44.4 245 15 8 8.8 4.8 32.3 90.2 -1.1 702 3.6
13000 8.2 46.8 245 14 7 8.7 4.8 32.2 89.9 -1.2 648 3.3
12500 9.4 48.9 250 14 7 8.5 4.7 32.0 89.7 -1.4 595 3.0
12000 10.7 51.3 255 13 7 8.3 4.5 31.8 89.2 -1.7 544 2.8
11500 11.9 53.4 260 12 6 8.2 4.5 31.6 88.8 -1.9 493 2.5
11000 13.1 55.6 265 12 6 8.0 4.4 31.3 88.4 -2.2 442 2.2
10500 14.3 57.7 270 12 6 3.9 2.1 31.1 88.0 -2.4 390 2.0
10250 14.4 57.9 270 12 6 4.9 2.7 30.5 86.8 -3.0 379 1.9
10000 15.1 59.2 275 12 6 11.0 6.0 30.5 86.8 -3.0 350 1.8
9750 15.9 60.6 275 11 6 10.1 5.5 30.5 86.8 -3.0 321 1.6
9500 16.6 61.9 280 11 6 7.8 4.3 30.5 86.9 -3.1 292 1.5
9250 17.0 62.6 285 11 6 4.7 2.6 30.1 86.3 -3.4 273 1.4
9000 17.4 63.3 285 11 6 7.7 4.2 29.9 85.7 -3.7 252 1.3
8750 18.1 64.6 290 11 5 10.0 5.5 29.8 85.7 -3.8 225 1.1
8500 18.7 65.7 290 10 5 7.4 4.0 29.8 85.6 -3.8 198 1.0
8250 19.1 66.4 295 10 5 4.4 2.4 29.4 85.0 -4.2 179 0.9
8000 19.5 67.1 295 10 5 6.1 3.3 29.1 84.3 -4.6 161 0.8
7750 20.0 68.0 300 10 5 8.4 4.6 28.9 84.0 -4.8 138 0.7
7500 20.5 68.9 300 9 5 5.6 3.1 28.7 83.7 -5.0 115 0.6
7250 20.8 69.4 300 9 5 3.2 1.7 28.3 82.9 -5.5 100 0.5
7000 21.0 69.8 300 9 5 3.9 2.2 27.8 82.1 -6.0 85 0.4
6750 21.2 70.2 305 9 5 2.9 1.6 27.3 81.2 -6.5 71 0.4
6500 21.3 70.3 300 8 4 0.7 0.4 26.7 80.1 -7.2 62 0.3
6250 21.3 70.3 295 7 4 -0.4 -0.2 26.0 78.8 -8.0 56 0.3
6000 21.2 70.2 290 7 4 0.5 0.3 25.2 77.4 -8.8 50 0.3
5750 21.2 70.2 280 6 3 -1.8 -1.0 24.5 76.1 -9.6 44 0.2
5500 20.7 69.3 270 4 2 -7.8 -4.3 23.4 74.2 -10.8 51 0.3
* * * * * * Numerical weather prediction model forecast data valid * * * * * *
07/01/2024 at 0900 MDT | 07/01/2024 at 1200 MDT
|
CAPE... +60.8 LI... -0.6 | CAPE... +46.0 LI... -0.4
CINH... -69.4 K Index... +28.9 | CINH... -39.0 K Index... +29.1
|
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 -63.8 -82.8 235 38 19 2.0 1.1 | -63.4 -82.1 235 43 22 1.9 1.1
45000 -58.3 -72.9 235 52 27 5.9 3.2 | -58.6 -73.5 240 57 29 5.6 3.1
40000 -49.1 -56.4 235 54 28 7.2 4.0 | -49.3 -56.7 235 61 32 7.3 4.0
38000 -44.7 -48.5 235 54 28 7.2 4.0 | -44.9 -48.8 235 59 31 7.3 4.0
36000 -40.4 -40.7 235 53 27 7.5 4.1 | -40.5 -40.9 235 57 29 7.7 4.2
34000 -35.7 -32.3 235 51 26 7.8 4.3 | -35.7 -32.3 235 54 28 8.1 4.4
32000 -31.1 -24.0 235 49 25 8.9 4.9 | -30.8 -23.4 230 50 26 9.3 5.1
30000 -26.3 -15.3 230 46 24 7.1 3.9 | -25.8 -14.4 230 45 23 7.6 4.2
29000 -24.2 -11.6 230 45 23 7.1 3.9 | -23.5 -10.3 230 43 22 7.6 4.2
28000 -22.1 -7.8 230 43 22 7.0 3.8 | -21.4 -6.5 230 41 21 6.5 3.6
27000 -20.0 -4.0 230 41 21 7.0 3.8 | -19.4 -2.9 230 41 21 6.6 3.6
26000 -18.0 -0.4 230 39 20 7.0 3.9 | -17.5 0.5 230 40 21 6.7 3.7
25000 -15.9 3.4 230 36 19 6.7 3.7 | -15.5 4.1 235 40 20 6.4 3.5
24000 -14.1 6.6 230 35 18 6.3 3.4 | -13.8 7.2 235 39 20 5.9 3.3
23000 -12.3 9.9 230 33 17 6.3 3.5 | -12.0 10.4 230 38 20 6.0 3.3
22000 -10.5 13.1 230 31 16 6.2 3.4 | -10.3 13.5 230 38 19 5.9 3.2
21000 -8.7 16.3 225 30 15 6.0 3.3 | -8.6 16.5 230 36 18 5.8 3.2
20000 -7.0 19.4 225 28 15 6.0 3.3 | -7.0 19.4 230 34 17 5.8 3.2
19500 -6.1 21.0 225 28 14 6.1 3.3 | -6.1 21.0 230 33 17 5.9 3.2
19000 -5.3 22.5 220 27 14 5.9 3.2 | -5.3 22.5 230 32 16 5.4 3.0
18500 -4.4 24.1 220 27 14 6.0 3.3 | -4.5 23.9 230 30 16 5.5 3.0
18000 -3.6 25.5 220 26 14 6.0 3.3 | -3.7 25.3 230 29 15 5.6 3.1
17500 -2.7 27.1 220 25 13 6.1 3.3 | -2.9 26.8 230 28 14 5.8 3.2
17000 -1.4 29.5 220 23 12 6.1 3.3 | -2.1 28.2 230 27 14 5.8 3.2
16500 -0.5 31.1 220 21 11 6.0 3.3 | -1.3 29.7 230 26 13 5.7 3.1
16000 0.4 32.7 220 20 10 5.9 3.3 | -0.1 31.8 235 24 13 5.6 3.1
15500 1.4 34.5 220 18 9 7.7 4.2 | 0.8 33.4 235 23 12 6.7 3.7
15000 2.5 36.5 225 17 9 7.5 4.1 | 1.8 35.2 235 23 12 6.6 3.6
14500 3.6 38.5 230 16 8 8.1 4.4 | 2.8 37.0 240 22 11 7.6 4.1
14000 4.8 40.6 235 15 8 8.2 4.5 | 3.9 39.0 240 21 11 7.8 4.3
13500 6.1 43.0 240 14 7 8.5 4.7 | 5.1 41.2 245 20 10 8.0 4.4
13000 7.4 45.3 245 14 7 8.8 4.8 | 6.3 43.3 250 19 10 8.1 4.5
12500 8.7 47.7 250 14 7 8.6 4.7 | 7.5 45.5 250 18 9 8.1 4.4
12000 9.9 49.8 255 15 7 8.2 4.5 | 8.7 47.7 255 17 9 8.0 4.4
11500 11.1 52.0 255 15 8 8.3 4.5 | 9.8 49.6 260 16 8 8.0 4.4
11000 12.3 54.1 260 15 8 8.4 4.6 | 11.0 51.8 260 16 8 8.0 4.4
10500 13.6 56.5 260 15 8 4.4 2.4 | 12.2 54.0 265 15 8 4.3 2.3
10250 13.8 56.8 260 15 7 5.6 3.1 | 12.4 54.3 265 16 8 5.5 3.0
10000 14.6 58.3 260 15 8 11.6 6.4 | 13.2 55.8 265 15 8 11.2 6.1
9750 15.3 59.5 260 15 8 10.4 5.7 | 13.9 57.0 270 15 7 10.2 5.6
9500 16.1 61.0 260 15 8 9.3 5.1 | 14.6 58.3 270 14 7 8.6 4.7
9250 16.7 62.1 265 15 8 7.2 3.9 | 15.1 59.2 275 14 7 5.7 3.1
9000 17.3 63.1 265 14 7 8.7 4.8 | 15.6 60.1 275 14 7 8.4 4.6
8750 18.0 64.4 260 14 7 10.1 5.5 | 16.4 61.5 275 13 7 10.7 5.9
8500 18.7 65.7 260 14 7 8.9 4.9 | 17.1 62.8 275 12 6 8.8 4.9
8250 19.3 66.7 260 14 7 7.5 4.1 | 17.6 63.7 275 11 6 5.6 3.1
8000 19.8 67.6 260 13 7 7.5 4.1 | 18.0 64.4 275 11 6 8.1 4.4
7750 20.4 68.7 260 13 7 8.4 4.6 | 18.8 65.8 275 11 5 12.5 6.9
7500 21.0 69.8 255 13 7 7.0 3.8 | 19.7 67.5 270 10 5 9.0 4.9
7250 21.4 70.5 255 13 6 5.4 2.9 | 20.1 68.2 270 9 5 5.0 2.7
7000 21.8 71.2 255 12 6 5.9 3.2 | 20.6 69.1 270 9 5 7.6 4.2
6750 22.2 72.0 250 12 6 7.1 3.9 | 21.3 70.3 270 9 5 13.9 7.6
6500 22.7 72.9 250 11 6 6.9 3.8 | 22.4 72.3 265 8 4 11.2 6.2
6250 23.2 73.8 245 11 5 6.5 3.6 | 22.9 73.2 265 7 4 6.7 3.7
6000 23.6 74.5 245 10 5 5.6 3.1 | 23.4 74.1 265 7 3 7.9 4.3
5750 24.0 75.2 240 9 5 7.5 4.1 | 24.1 75.4 265 6 3 13.2 7.3
5500 24.8 76.6 235 8 4 16.2 8.9 | 25.4 77.7 260 6 3 22.4 12.3
07/01/2024 at 1500 MDT | 07/01/2024 at 1800 MDT
|
CAPE... +105.8 LI... -1.4 | CAPE... +186.4 LI... -2.2
CINH... -25.4 K Index... +28.4 | CINH... -53.4 K Index... +28.2
|
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 -64.1 -83.4 240 46 24 2.0 1.1 | -63.4 -82.1 240 42 21 1.9 1.1
45000 -59.0 -74.2 240 59 31 6.0 3.3 | -58.6 -73.5 235 56 29 5.5 3.0
40000 -49.1 -56.4 235 65 33 7.6 4.2 | -49.2 -56.6 230 62 32 8.1 4.4
38000 -44.5 -48.1 230 65 34 7.6 4.2 | -44.4 -47.9 225 62 32 8.0 4.4
36000 -39.9 -39.8 230 66 34 7.9 4.4 | -39.6 -39.3 225 62 32 8.1 4.4
34000 -35.0 -31.0 230 62 32 8.2 4.5 | -34.7 -30.5 225 59 30 8.1 4.5
32000 -30.1 -22.2 230 59 30 9.3 5.1 | -29.8 -21.6 225 57 29 8.1 4.4
30000 -25.7 -14.3 230 54 28 7.4 4.0 | -25.6 -14.1 230 55 28 6.9 3.8
29000 -23.5 -10.3 230 52 27 7.4 4.1 | -23.0 -9.4 235 54 28 6.9 3.8
28000 -20.8 -5.4 225 49 25 6.4 3.5 | -21.0 -5.8 235 53 27 6.6 3.6
27000 -18.9 -2.0 225 45 23 6.5 3.6 | -19.0 -2.2 240 50 26 6.7 3.7
26000 -17.0 1.4 225 41 21 6.6 3.6 | -17.1 1.2 240 47 24 6.7 3.7
25000 -15.1 4.8 225 38 19 6.2 3.4 | -15.1 4.8 240 44 23 6.6 3.6
24000 -13.4 7.9 230 36 19 5.7 3.1 | -13.2 8.2 245 41 21 6.3 3.5
23000 -11.7 10.9 235 35 18 5.7 3.1 | -11.3 11.7 250 37 19 6.3 3.5
22000 -10.1 13.8 240 34 18 5.6 3.1 | -9.4 15.1 255 34 18 5.7 3.1
21000 -8.5 16.7 240 30 16 5.3 2.9 | -8.2 17.2 260 33 17 4.1 2.3
20000 -7.0 19.4 240 27 14 5.3 2.9 | -7.0 19.4 270 32 16 4.1 2.3
19500 -6.2 20.8 245 25 13 5.3 2.9 | -6.4 20.5 270 31 16 4.0 2.2
19000 -5.4 22.3 245 24 12 5.7 3.1 | -5.7 21.7 275 31 16 5.5 3.0
18500 -4.5 23.9 250 24 12 5.7 3.1 | -4.9 23.2 275 31 16 5.6 3.1
18000 -3.7 25.3 255 24 12 5.9 3.2 | -4.1 24.6 275 31 16 5.9 3.3
17500 -2.8 27.0 260 23 12 6.3 3.4 | -3.2 26.2 280 30 15 6.8 3.7
17000 -1.9 28.6 260 22 12 6.3 3.4 | -2.3 27.9 280 29 15 6.8 3.7
16500 -1.0 30.2 265 22 11 6.7 3.7 | -1.3 29.7 285 27 14 7.9 4.3
16000 0.0 32.0 265 22 11 6.7 3.7 | -0.2 31.6 285 26 13 8.0 4.4
15500 1.0 33.8 270 22 11 6.8 3.7 | 0.9 33.6 285 24 12 8.5 4.7
15000 1.9 35.4 270 21 11 6.9 3.8 | 2.3 36.1 290 23 12 9.1 5.0
14500 2.9 37.2 275 20 10 7.2 3.9 | 3.6 38.5 290 22 11 9.1 5.0
14000 4.1 39.4 275 19 10 8.4 4.6 | 5.0 41.0 290 20 11 9.2 5.1
13500 5.3 41.5 275 17 9 8.3 4.5 | 7.0 44.6 290 18 9 9.2 5.0
13000 7.2 45.0 275 15 8 8.9 4.9 | 8.4 47.1 290 17 9 9.1 5.0
12500 8.5 47.3 280 13 7 8.9 4.9 | 9.7 49.5 290 16 8 9.0 4.9
12000 9.8 49.6 280 13 6 8.9 4.9 | 11.0 51.8 290 14 7 8.7 4.8
11500 11.1 52.0 280 12 6 9.0 4.9 | 12.3 54.1 285 13 7 8.5 4.7
11000 12.5 54.5 275 11 6 9.0 4.9 | 13.4 56.1 280 12 6 7.0 3.8
10500 13.8 56.8 275 10 5 4.1 2.2 | 14.3 57.7 275 10 5 10.9 6.0
10250 14.0 57.2 275 10 5 5.2 2.8 | 15.3 59.5 260 10 5 11.5 6.3
10000 14.8 58.6 270 9 5 12.5 6.8 | 15.9 60.6 255 9 5 6.7 3.6
9750 15.6 60.1 270 8 4 11.1 6.1 | 16.4 61.5 245 9 5 8.2 4.5
9500 16.4 61.5 265 8 4 9.2 5.1 | 17.0 62.6 235 9 5 6.9 3.8
9250 16.9 62.4 260 7 4 6.2 3.4 | 17.4 63.3 230 9 5 5.5 3.0
9000 17.5 63.5 255 7 4 8.9 4.9 | 17.9 64.2 225 9 5 7.4 4.1
8750 18.3 64.9 245 7 3 10.9 6.0 | 18.5 65.3 215 10 5 9.1 5.0
8500 19.0 66.2 235 6 3 9.0 5.0 | 19.1 66.4 210 11 6 8.4 4.6
8250 19.6 67.3 230 7 3 5.6 3.1 | 19.6 67.3 205 12 6 6.8 3.7
8000 20.0 68.0 220 7 4 7.6 4.2 | 20.1 68.2 205 12 6 7.6 4.2
7750 20.7 69.3 215 8 4 10.9 6.0 | 20.8 69.4 200 12 6 9.5 5.2
7500 21.5 70.7 210 8 4 8.9 4.9 | 21.4 70.5 200 13 7 8.7 4.8
7250 22.0 71.6 205 8 4 7.0 3.9 | 22.0 71.6 195 13 7 7.8 4.3
7000 22.5 72.5 205 9 4 8.3 4.6 | 22.6 72.7 195 13 7 8.2 4.5
6750 23.2 73.8 200 9 4 11.5 6.3 | 23.2 73.8 195 14 7 10.1 5.5
6500 24.1 75.4 195 9 5 10.7 5.8 | 24.0 75.2 190 14 7 9.7 5.3
6250 24.7 76.5 195 9 4 9.0 4.9 | 24.6 76.3 190 14 7 8.6 4.7
6000 25.4 77.7 195 8 4 8.9 4.9 | 25.3 77.5 190 14 7 8.6 4.7
5750 26.2 79.2 190 8 4 14.2 7.8 | 26.0 78.8 190 13 7 11.6 6.4
5500 27.7 81.9 190 8 4 25.6 14.0 | 27.0 80.6 185 12 6 17.9 9.8
________________________________________________________________________________
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.
042613