Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
327
UXUS97 KPUB 141206
SRGPUB
Soaring Forecast
National Weather Service Pueblo, Colorado
0506 MST Thursday, November 14, 2024
This forecast is for Villa Grove, CO for Thursday, November 14, 2024:
If the trigger temperature of 57.8 F/14.3 C is reached...then
Thermal Soaring Index....................... Fair
Maximum rate of lift........................ 270 ft/min (1.4 m/s)
Maximum height of thermals.................. 10519 ft MSL (1530 ft AGL)
Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... None
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................. 9939 ft MSL (950 ft AGL)
Thermal soaring outlook for Friday 11/15....... Good
Wave Soaring Index............................. Not available
Remarks...
Sunrise/Sunset.................... 06:44:40 / 16:51:31 MST
Total possible sunshine........... 10 hr 6 min 50 sec (606 min 50 sec)
Altitude of sun at 11:48:06 MST... 33.17 degrees
Upper air data from numerical model forecast valid on 11/14/2024 at 0500 MST
Freezing level.................. 9414 ft MSL (425 ft AGL)
Additional freezing level....... 14393 ft MSL (5404 ft AGL)
Convective condensation level... 25038 ft MSL (16049 ft AGL)
Lifted condensation level....... 19470 ft MSL (10481 ft AGL)
Lifted index.................... +11.9
K index......................... -25.6
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 -67.8 -90.0 265 66 34 1.4 0.8 M M M M M
45000 -64.7 -84.5 265 73 37 5.0 2.7 M M M M M
40000 -57.2 -71.0 260 68 35 5.3 2.9 M M M M M
38000 -53.6 -64.5 265 67 34 6.2 3.4 M M M M M
36000 -49.9 -57.8 265 65 34 6.1 3.4 M M M M M
34000 -45.5 -49.9 265 64 33 8.2 4.5 M M M M M
32000 -40.6 -41.1 265 63 33 8.2 4.5 M M M M M
30000 -35.5 -31.9 265 63 33 7.2 3.9 28.5 83.3 15.9 M M
29000 -33.4 -28.1 270 64 33 7.2 3.9 27.5 81.6 15.3 M M
28000 -31.2 -24.2 270 64 33 7.2 4.0 26.7 80.1 14.8 M M
27000 -29.1 -20.4 270 63 32 6.8 3.7 25.6 78.1 14.1 M M
26000 -27.1 -16.8 270 60 31 6.8 3.7 24.5 76.0 13.3 M M
25000 -25.1 -13.2 270 58 30 6.8 3.8 23.5 74.2 12.6 M M
24000 -22.8 -9.0 270 55 29 8.4 4.6 22.7 72.8 12.1 M M
23000 -20.3 -4.5 265 53 27 8.4 4.6 22.2 71.9 11.8 M M
22000 -17.8 -0.0 260 50 26 8.4 4.6 21.8 71.2 11.6 M M
21000 -15.3 4.5 260 48 25 8.3 4.6 21.3 70.3 11.3 M M
20000 -12.8 9.0 260 47 24 8.3 4.5 20.7 69.3 10.9 M M
19500 -11.6 11.1 260 46 24 8.3 4.5 20.5 68.9 10.8 M M
19000 -10.3 13.5 260 45 23 8.1 4.5 20.3 68.6 10.7 M M
18500 -9.2 15.4 260 44 23 7.7 4.2 20.0 68.0 10.5 M M
18000 -8.0 17.6 260 43 22 7.8 4.3 19.7 67.4 10.2 M M
17500 -6.9 19.6 260 42 22 7.1 3.9 19.3 66.7 9.9 M M
17000 -5.8 21.6 260 41 21 7.0 3.8 18.8 65.9 9.6 M M
16500 -4.8 23.4 260 41 21 7.1 3.9 18.4 65.1 9.2 M M
16000 -3.7 25.3 260 40 21 7.3 4.0 18.0 64.4 8.9 M M
15500 -2.1 28.2 260 40 20 7.0 3.9 17.4 63.3 8.4 M M
15000 -1.0 30.2 260 39 20 6.8 3.7 16.9 62.5 8.0 M M
14500 -0.0 32.0 260 39 20 6.3 3.4 16.5 61.6 7.6 M M
14000 0.8 33.4 260 40 20 5.6 3.1 15.8 60.4 7.0 M M
13500 1.7 35.1 265 40 20 5.5 3.0 15.1 59.3 6.4 M M
13000 2.3 36.1 265 40 20 3.9 2.2 14.3 57.8 5.6 M M
12500 2.9 37.2 265 39 20 4.8 2.6 13.5 56.3 4.8 M M
12000 3.4 38.1 265 39 20 1.8 1.0 12.5 54.4 3.8 M M
11750 3.5 38.3 265 38 19 2.7 1.5 11.9 53.4 3.3 M M
11500 3.7 38.7 265 37 19 3.4 1.8 11.4 52.5 2.8 M M
11250 3.9 39.0 265 36 19 1.3 0.7 10.9 51.5 2.2 M M
11000 3.9 39.0 265 34 17 -0.9 -0.5 10.1 50.1 1.5 M M
10750 3.8 38.8 265 31 16 -1.5 -0.8 9.3 48.7 0.7 M M
10500 3.7 38.7 265 29 15 -0.2 -0.1 8.4 47.1 -0.2 269 1.4
10250 3.6 38.5 265 26 14 -6.9 -3.8 7.6 45.6 -1.1 266 1.4
10000 2.6 36.7 260 25 13 -14.4 -7.9 5.9 42.5 -2.8 288 1.5
9750 1.6 34.9 260 23 12 -12.9 -7.1 4.1 39.4 -4.5 311 1.6
9500 0.5 32.9 255 21 11 -16.1 -8.8 2.3 36.2 -6.4 336 1.7
9250 -1.3 29.7 250 18 9 -33.6 -18.4 -0.1 31.8 -8.9 382 1.9
9000 -5.6 21.9 235 9 5 -91.2 -50.0 -5.2 22.7 -14.0 505 2.6
8750 M M M M M M M M M M M M
8500 M M M M M M M M M M M M
8250 M M M M M M M M M M M M
8000 M M M M M M M M M M M M
* * * * * * Numerical weather prediction model forecast data valid * * * * * *
11/14/2024 at 0800 MST | 11/14/2024 at 1100 MST
|
CAPE... 0.0 LI... +1.9 | CAPE... 0.0 LI... +2.1
CINH... 0.0 K Index... -23.7 | CINH... 0.0 K Index... -25.5
|
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 -67.2 -89.0 260 65 34 2.0 1.1 | -66.6 -87.9 255 63 33 1.8 1.0
45000 -63.4 -82.1 265 74 38 4.6 2.5 | -63.1 -81.6 255 70 36 4.3 2.4
40000 -56.6 -69.9 255 70 36 5.0 2.7 | -56.7 -70.1 250 70 36 4.6 2.5
38000 -53.0 -63.4 255 66 34 6.1 3.3 | -53.2 -63.8 250 68 35 5.8 3.2
36000 -49.4 -56.9 255 63 32 6.1 3.3 | -49.8 -57.6 250 66 34 5.8 3.2
34000 -45.2 -49.4 255 60 31 7.6 4.2 | -45.8 -50.4 250 66 34 7.3 4.0
32000 -40.6 -41.1 255 59 31 7.6 4.2 | -41.4 -42.5 255 67 34 7.3 4.0
30000 -35.6 -32.1 260 61 31 7.3 4.0 | -36.3 -33.3 255 66 34 7.8 4.3
29000 -33.4 -28.1 260 63 32 7.3 4.0 | -34.0 -29.2 255 66 34 7.8 4.3
28000 -31.3 -24.3 260 64 33 7.3 4.0 | -31.6 -24.9 255 65 33 7.9 4.3
27000 -29.1 -20.4 260 64 33 7.1 3.9 | -29.4 -20.9 255 63 32 7.4 4.0
26000 -27.0 -16.6 265 62 32 7.1 3.9 | -27.2 -17.0 255 60 31 7.4 4.0
25000 -24.8 -12.6 265 60 31 7.1 3.9 | -24.9 -12.8 255 58 30 7.4 4.1
24000 -22.6 -8.7 265 58 30 7.8 4.3 | -22.7 -8.9 255 55 28 7.9 4.3
23000 -20.3 -4.5 260 54 28 7.8 4.3 | -20.3 -4.5 250 53 27 7.9 4.3
22000 -17.9 -0.2 260 50 26 7.8 4.3 | -17.9 -0.2 250 50 26 7.9 4.3
21000 -15.5 4.1 255 48 24 8.3 4.5 | -15.5 4.1 250 48 25 8.2 4.5
20000 -13.0 8.6 255 46 24 8.3 4.5 | -13.1 8.4 250 47 24 8.2 4.5
19500 -11.8 10.8 255 45 23 8.3 4.5 | -11.8 10.8 250 46 24 8.2 4.5
19000 -10.5 13.1 255 44 23 8.1 4.4 | -10.6 12.9 250 45 23 8.0 4.4
18500 -9.4 15.1 255 43 22 7.4 4.1 | -9.5 14.9 250 43 22 7.3 4.0
18000 -8.3 17.1 255 41 21 7.4 4.1 | -8.4 16.9 250 42 22 7.3 4.0
17500 -7.2 19.0 260 40 21 7.3 4.0 | -7.3 18.9 250 41 21 7.1 3.9
17000 -6.1 21.0 260 39 20 7.3 4.0 | -6.3 20.7 250 39 20 7.1 3.9
16500 -5.0 23.0 260 38 19 7.3 4.0 | -5.2 22.6 250 38 20 7.1 3.9
16000 -3.9 25.0 260 37 19 7.3 4.0 | -4.1 24.6 250 37 19 7.3 4.0
15500 -2.8 27.0 260 37 19 7.3 4.0 | -3.0 26.6 250 37 19 7.2 4.0
15000 -1.1 30.0 260 37 19 7.4 4.1 | -1.3 29.7 255 37 19 7.6 4.2
14500 -0.0 32.0 260 37 19 6.3 3.4 | -0.1 31.8 255 36 19 5.7 3.1
14000 0.8 33.4 260 38 19 5.5 3.0 | 0.5 32.9 255 37 19 5.7 3.1
13500 1.6 34.9 260 38 20 5.4 2.9 | 1.4 34.5 260 37 19 5.3 2.9
13000 2.2 36.0 265 38 20 3.4 1.9 | 1.9 35.4 260 37 19 3.5 1.9
12500 2.7 36.9 265 38 20 3.9 2.1 | 2.5 36.5 265 37 19 4.1 2.3
12000 3.2 37.8 265 38 19 2.2 1.2 | 3.1 37.6 265 35 18 3.9 2.1
11750 3.3 37.9 265 37 19 2.7 1.5 | 3.4 38.1 265 33 17 3.9 2.1
11500 3.5 38.3 265 36 19 3.2 1.8 | 3.7 38.7 265 31 16 4.2 2.3
11250 3.7 38.7 265 35 18 1.6 0.9 | 4.0 39.2 265 29 15 3.1 1.7
11000 3.7 38.7 265 33 17 0.0 0.0 | 4.2 39.6 265 28 15 1.9 1.0
10750 3.7 38.7 265 31 16 -0.9 -0.5 | 4.3 39.7 265 27 14 1.4 0.8
10500 3.6 38.5 265 28 14 0.0 0.0 | 4.3 39.7 265 25 13 1.9 1.1
10250 3.5 38.3 260 25 13 -6.9 -3.8 | 4.4 39.9 265 23 12 -1.3 -0.7
10000 2.5 36.5 260 23 12 -14.2 -7.8 | 4.0 39.2 260 21 11 -5.2 -2.9
9750 1.5 34.7 255 22 11 -12.6 -6.9 | 3.6 38.5 255 18 9 -4.2 -2.3
9500 0.4 32.7 250 20 10 -16.2 -8.9 | 3.4 38.1 250 16 8 -0.4 -0.2
9250 -1.1 30.0 240 17 9 -22.9 -12.6 | 3.6 38.5 240 13 7 11.5 6.3
9000 -3.1 26.4 230 9 4 -27.3 -15.0 | 5.2 41.4 235 9 5 32.4 17.8
8750 M M M M M M M | M M M M M M M
8500 M M M M M M M | M M M M M M M
8250 M M M M M M M | M M M M M M M
8000 M M M M M M M | M M M M M M M
11/14/2024 at 1400 MST | 11/14/2024 at 1700 MST
|
CAPE... 0.0 LI... +1.9 | CAPE... 0.0 LI... +2.3
CINH... 0.0 K Index... -27.2 | CINH... 0.0 K Index... -28.9
|
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 -66.7 -88.1 255 65 33 2.4 1.3 | -66.6 -87.9 255 65 34 1.9 1.0
45000 -62.5 -80.5 250 72 37 4.1 2.3 | -63.4 -82.1 250 76 39 3.9 2.2
40000 -56.4 -69.5 250 73 37 4.3 2.3 | -57.2 -71.0 245 77 40 4.2 2.3
38000 -53.1 -63.6 250 73 38 5.4 3.0 | -53.7 -64.7 245 76 39 5.9 3.3
36000 -49.9 -57.8 250 74 38 5.4 3.0 | -50.1 -58.2 245 75 39 5.9 3.3
34000 -46.0 -50.8 250 73 38 7.5 4.1 | -46.1 -51.0 245 74 38 7.5 4.1
32000 -41.5 -42.7 250 72 37 7.5 4.1 | -41.6 -42.9 245 72 37 7.5 4.1
30000 -36.3 -33.3 250 69 35 7.8 4.3 | -37.0 -34.6 245 71 37 8.0 4.4
29000 -34.0 -29.2 250 67 34 7.8 4.3 | -34.0 -29.2 245 70 36 8.0 4.4
28000 -31.6 -24.9 250 65 33 7.8 4.3 | -31.6 -24.9 245 69 36 8.1 4.4
27000 -29.3 -20.7 250 61 31 7.5 4.1 | -29.3 -20.7 245 67 34 7.3 4.0
26000 -27.1 -16.8 245 56 29 7.5 4.1 | -27.1 -16.8 245 63 33 7.3 4.0
25000 -24.8 -12.6 245 51 26 7.5 4.1 | -24.9 -12.8 240 60 31 7.3 4.0
24000 -22.6 -8.7 240 49 25 7.7 4.2 | -22.7 -8.9 240 57 30 8.1 4.4
23000 -20.3 -4.5 240 49 25 7.7 4.2 | -20.2 -4.4 240 55 28 8.1 4.4
22000 -18.0 -0.4 245 49 25 7.7 4.2 | -17.8 -0.0 240 52 27 8.1 4.4
21000 -15.6 3.9 245 47 24 8.2 4.5 | -15.4 4.3 240 49 25 8.2 4.5
20000 -13.1 8.4 245 45 23 8.2 4.5 | -12.9 8.8 240 46 24 8.2 4.5
19500 -11.9 10.6 245 44 23 8.2 4.5 | -11.7 10.9 240 44 23 8.2 4.5
19000 -10.6 12.9 240 43 22 8.0 4.4 | -10.5 13.1 240 43 22 8.0 4.4
18500 -9.5 14.9 240 42 22 7.1 3.9 | -9.4 15.1 240 41 21 7.1 3.9
18000 -8.5 16.7 240 41 21 7.2 3.9 | -8.3 17.1 240 40 20 7.2 3.9
17500 -7.4 18.7 245 40 20 7.2 3.9 | -7.3 18.9 240 38 20 6.5 3.6
17000 -6.3 20.7 245 39 20 7.2 3.9 | -6.3 20.7 240 36 19 6.4 3.5
16500 -5.2 22.6 245 38 19 7.3 4.0 | -5.4 22.3 240 35 18 6.6 3.6
16000 -4.1 24.6 245 37 19 7.5 4.1 | -4.3 24.3 240 33 17 7.3 4.0
15500 -3.0 26.6 245 36 18 7.4 4.1 | -3.2 26.2 240 32 17 7.3 4.0
15000 -1.3 29.7 250 35 18 7.5 4.1 | -2.1 28.2 245 31 16 7.1 3.9
14500 -0.2 31.6 250 34 18 6.4 3.5 | -0.5 31.1 250 30 15 6.0 3.3
14000 0.6 33.1 255 34 18 4.7 2.6 | 0.2 32.4 255 29 15 4.4 2.4
13500 1.2 34.2 255 34 18 4.8 2.6 | 0.8 33.4 255 28 15 4.4 2.4
13000 1.8 35.2 260 34 18 3.0 1.7 | 1.4 34.5 260 26 14 4.0 2.2
12500 2.3 36.1 265 35 18 3.4 1.8 | 2.0 35.6 260 23 12 4.5 2.5
12000 2.7 36.9 265 34 17 3.3 1.8 | 2.5 36.5 260 19 10 4.5 2.5
11750 3.0 37.4 270 32 16 5.6 3.1 | 2.9 37.2 260 17 9 5.3 2.9
11500 3.4 38.1 270 30 15 6.0 3.3 | 3.2 37.8 255 15 8 5.7 3.1
11250 3.8 38.8 270 28 14 5.3 2.9 | 3.6 38.5 255 14 7 4.9 2.7
11000 4.2 39.6 270 25 13 4.4 2.4 | 3.9 39.0 250 12 6 4.1 2.3
10750 4.4 39.9 270 23 12 4.4 2.4 | 4.2 39.6 250 12 6 3.4 1.9
10500 4.7 40.5 265 20 10 4.7 2.6 | 4.4 39.9 250 11 5 4.0 2.2
10250 5.0 41.0 265 18 9 4.0 2.2 | 4.7 40.5 250 10 5 0.1 0.1
10000 5.2 41.4 260 16 8 3.1 1.7 | 4.4 39.9 245 10 5 -4.7 -2.6
9750 5.4 41.7 255 14 7 3.6 2.0 | 4.0 39.2 240 10 5 -4.9 -2.7
9500 5.7 42.3 250 13 6 5.8 3.2 | 3.6 38.5 235 10 5 -4.3 -2.3
9250 6.3 43.3 240 11 6 11.2 6.2 | 3.1 37.6 225 10 5 -12.9 -7.1
9000 7.4 45.3 235 8 4 22.1 12.1 | 0.3 32.5 215 6 3 -74.9 -41.1
8750 M M M M M M M | M M M M M M M
8500 M M M M M M M | M M M M M M M
8250 M M M M M M M | M M M M M M M
8000 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). 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 Villa Grove, Colorado at:
North Latitude: 38 deg 16 min 03 sec
West Longitude: 105 deg 53 min 37 sec
Elevation: 7986 feet (2434 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.
CIN (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