Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 141229
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0629 MDT Thursday, March 14, 2024

This forecast is for the Air Force Academy for Thursday, March 14, 2024:

If the trigger temperature of 35.6 F/2.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7597 ft MSL (0 ft AGL)

Forecast maximum temperature................... 29.0 F/-2.1 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Friday 03/15....... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:10:46 / 19:05:41 MDT
Total possible sunshine........... 11 hr 54 min 55 sec (714 min 55 sec)
Altitude of sun at 13:08:14 MDT... 48.87 degrees

Upper air data from numerical model forecast valid on 03/14/2024 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10431 ft MSL (2834 ft AGL)
Lifted condensation level....... 9417 ft MSL (1820 ft AGL)
Lifted index.................... +5.5
K index......................... +16.7

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  -53.6 -64.5   255   15    8   1.5   0.8      M     M       M      M    M
 45000  -51.3 -60.3   230   23   12   1.4   0.8      M     M       M      M    M
 40000  -51.6 -60.9   230   26   14  -0.4  -0.2      M     M       M      M    M
 38000  -52.0 -61.6   230   27   14  -2.3  -1.3      M     M       M      M    M
 36000  -53.2 -63.8   220   28   14  -2.1  -1.2      M     M       M      M    M
 34000  -54.5 -66.1   210   29   15  -2.0  -1.1      M     M       M      M    M
 32000  -54.2 -65.6   190   25   13   1.2   0.7      M     M       M      M    M
 30000  -53.5 -64.3   165   24   12   2.0   1.1      M     M       M      M    M
 29000  -51.0 -59.8   165   23   12   9.8   5.4   13.5  56.3    11.8      M    M
 28000  -48.1 -54.6   165   22   11   9.8   5.4   13.5  56.3    11.9      M    M
 27000  -45.1 -49.2   165   20   11   9.8   5.4   13.6  56.5    12.1      M    M
 26000  -42.3 -44.1   165   20   10   9.5   5.2   13.6  56.4    12.3      M    M
 25000  -39.4 -38.9   170   19   10   9.5   5.2   13.4  56.2    12.3      M    M
 24000  -36.6 -33.9   170   19   10   9.5   5.2   13.4  56.1    12.4      M    M
 23000  -33.9 -29.0   170   18    9   8.3   4.6   13.2  55.7    12.4      M    M
 22000  -31.4 -24.5   170   17    9   8.4   4.6   12.6  54.7    12.0      M    M
 21000  -28.9 -20.0   170   15    8   8.4   4.6   12.2  54.0    11.8      M    M
 20000  -26.5 -15.7   165   13    7   7.6   4.2   11.6  52.8    11.4      M    M
 19500  -24.9 -12.8   160   11    5   7.6   4.2   11.0  51.8    10.9      M    M
 19000  -23.7 -10.7   150    9    5   7.6   4.2   10.6  51.1    10.7      M    M
 18500  -22.6  -8.7   145    8    4   7.6   4.2   10.3  50.5    10.4      M    M
 18000  -21.6  -6.9   135    7    4   6.6   3.6    9.9  49.7    10.1      M    M
 17500  -20.6  -5.1   115    6    3   6.7   3.7    9.3  48.8     9.7      M    M
 17000  -19.6  -3.3   095    6    3   6.8   3.7    8.9  47.9     9.3      M    M
 16500  -18.6  -1.5   080    7    4   6.8   3.7    8.4  47.0     8.9      M    M
 16000  -17.6   0.3   065    9    4   6.7   3.7    7.9  46.2     8.5      M    M
 15500  -16.6   2.1   065   11    6   6.4   3.5    7.3  45.2     8.0      M    M
 15000  -15.7   3.7   060   14    7   6.3   3.5    6.8  44.3     7.6      M    M
 14500  -14.9   5.2   060   17    9   4.0   2.2    6.0  42.9     6.9      M    M
 14000  -14.3   6.3   065   20   10   4.0   2.2    5.2  41.3     6.1      M    M
 13500  -13.6   7.5   065   22   11   6.2   3.4    4.4  40.0     5.4      M    M
 13000  -12.7   9.1   060   23   12   5.5   3.0    3.8  38.9     4.8      M    M
 12500  -11.6  11.1   060   24   12   8.1   4.4    3.5  38.3     4.5      M    M
 12000  -10.7  12.7   060   24   13   6.4   3.5    2.9  37.2     4.0      M    M
 11750  -10.2  13.6   060   25   13   5.8   3.2    2.6  36.8     3.7      M    M
 11500   -9.8  14.4   055   25   13   6.1   3.3    2.3  36.2     3.4      M    M
 11250   -9.3  15.3   055   25   13   7.3   4.0    2.1  35.8     3.2      M    M
 11000   -8.8  16.2   055   25   13   8.0   4.4    1.9  35.5     3.0      M    M
 10750   -8.2  17.2   055   26   13   7.0   3.8    1.8  35.2     2.9      M    M
 10500   -7.8  18.0   055   26   14   5.3   2.9    1.5  34.7     2.6      M    M
 10250   -7.3  18.9   055   27   14   7.5   4.1    1.2  34.1     2.3      M    M
 10000   -6.7  19.9   055   28   14  10.0   5.5    1.1  34.1     2.2      M    M
  9750   -6.0  21.2   050   28   15   8.5   4.7    1.1  34.0     2.2      M    M
  9500   -5.4  22.3   050   28   14   7.7   4.2    1.0  33.7     2.0      M    M
  9250   -4.9  23.2   050   28   14   7.9   4.3    0.8  33.5     1.9      M    M
  9000   -4.3  24.3   045   28   14   7.3   4.0    0.7  33.2     1.7      M    M
  8750   -3.8  25.2   045   26   14   6.6   3.6    0.5  32.8     1.5      M    M
  8500   -3.4  25.9   040   25   13   6.4   3.5    0.2  32.3     1.2      M    M
  8250   -2.9  26.8   035   23   12   6.3   3.5   -0.1  31.9     0.9      M    M
  8000   -2.4  27.7   035   21   11   7.1   3.9   -0.3  31.5     0.7      M    M
  7750   -1.9  28.6   030   16    8   8.8   4.8   -0.4  31.2     0.5      M    M
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           03/14/2024 at 0900 MDT          |       03/14/2024 at 1200 MDT
                                           |
CAPE...   +18.1    LI...       +0.7        | CAPE...   +15.4    LI...       +1.7
CINH...     0.0    K Index... +17.9        | CINH...     0.0    K Index... +17.4
                                           |
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  260  14  7   1.8   1.0 | -54.0 -65.2  260  13  6   2.0   1.1
 45000 -50.5 -58.9  240  22 11   1.7   0.9 | -51.1 -60.0  260  17  9   1.9   1.0
 40000 -52.0 -61.6  230  30 15  -1.4  -0.7 | -53.0 -63.4  235  29 15  -1.7  -0.9
 38000 -52.7 -62.9  230  33 17  -0.3  -0.2 | -53.8 -64.8  230  35 18   0.9   0.5
 36000 -53.0 -63.4  220  32 16  -0.4  -0.2 | -53.3 -63.9  225  39 20   0.7   0.4
 34000 -53.3 -63.9  215  32 16  -0.5  -0.3 | -52.9 -63.2  220  42 22   0.7   0.4
 32000 -53.2 -63.8  185  22 11   0.3   0.1 | -52.4 -62.3  205  29 15   0.9   0.5
 30000 -53.0 -63.4  135  24 12   1.1   0.6 | -51.9 -61.4  165  19 10   2.1   1.2
 29000 -50.8 -59.4  130  23 12   8.8   4.8 | -49.9 -57.8  145  18  9   7.6   4.2
 28000 -48.2 -54.8  130  21 11   8.7   4.8 | -47.6 -53.7  130  19 10   7.6   4.2
 27000 -45.6 -50.1  125  20 10   8.7   4.8 | -45.3 -49.5  115  21 11   7.7   4.2
 26000 -42.9 -45.2  125  18  9   9.3   5.1 | -42.9 -45.2  110  21 11   8.7   4.8
 25000 -40.1 -40.2  125  17  9   9.3   5.1 | -40.3 -40.5  115  19 10   8.7   4.8
 24000 -37.4 -35.3  125  15  8   9.3   5.1 | -37.7 -35.9  120  16  8   8.7   4.8
 23000 -34.7 -30.5  125  14  7   8.2   4.5 | -35.0 -31.0  125  15  8   8.9   4.9
 22000 -32.3 -26.1  120  14  7   8.2   4.5 | -32.4 -26.3  125  15  8   8.9   4.9
 21000 -29.8 -21.6  115  14  7   8.2   4.5 | -29.7 -21.5  125  15  8   9.0   4.9
 20000 -27.5 -17.5  110  13  7   7.5   4.1 | -26.6 -15.9  125  15  8   8.3   4.5
 19500 -25.9 -14.6  105  12  6   7.5   4.1 | -25.4 -13.7  125  15  8   8.3   4.5
 19000 -24.7 -12.5  100  12  6   7.5   4.1 | -24.2 -11.6  120  15  8   8.3   4.5
 18500 -23.6 -10.5  095  11  6   7.5   4.1 | -22.9  -9.2  120  15  8   8.0   4.4
 18000 -22.5  -8.5  095  12  6   7.3   4.0 | -21.8  -7.2  120  15  8   7.1   3.9
 17500 -21.5  -6.7  095  12  6   7.3   4.0 | -20.8  -5.4  120  15  8   7.2   4.0
 17000 -20.4  -4.7  095  13  7   7.4   4.1 | -19.8  -3.6  115  14  7   6.4   3.5
 16500 -19.3  -2.7  095  14  7   7.4   4.1 | -18.8  -1.8  110  13  7   6.5   3.5
 16000 -18.2  -0.8  095  15  8   7.4   4.1 | -17.8  -0.0  100  12  6   6.6   3.6
 15500 -17.1   1.2  085  16  8   7.4   4.1 | -16.9   1.6  090  13  7   6.8   3.7
 15000 -16.0   3.2  080  18  9   7.4   4.0 | -15.9   3.4  085  13  7   6.7   3.7
 14500 -14.9   5.2  075  19 10   7.1   3.9 | -14.9   5.2  080  15  8   6.7   3.7
 14000 -13.9   7.0  070  20 10   7.1   3.9 | -13.9   7.0  080  16  8   6.6   3.6
 13500 -12.9   8.8  065  22 11   6.9   3.8 | -12.9   8.8  075  17  9   6.4   3.5
 13000 -11.9  10.6  060  23 12   6.8   3.7 | -12.0  10.4  075  17  9   6.4   3.5
 12500 -10.8  12.6  055  24 13   5.8   3.2 | -11.0  12.2  070  17  9   5.8   3.2
 12000 -10.3  13.5  055  26 13   3.6   2.0 | -10.3  13.5  060  18  9   4.7   2.6
 11750 -10.0  14.0  050  26 14   3.2   1.7 | -10.0  14.0  060  18  9   5.3   2.9
 11500  -9.8  14.4  050  27 14   3.2   1.7 |  -9.6  14.7  055  19 10   5.6   3.1
 11250  -9.5  14.9  050  28 14   3.7   2.1 |  -9.2  15.4  050  19 10   4.9   2.7
 11000  -9.2  15.4  050  28 14   4.0   2.2 |  -8.9  16.0  050  20 10   4.4   2.4
 10750  -8.9  16.0  050  28 15   4.1   2.2 |  -8.5  16.7  045  21 11   4.0   2.2
 10500  -8.7  16.3  050  29 15   3.4   1.9 |  -8.3  17.1  040  22 11   3.5   1.9
 10250  -8.4  16.9  045  29 15   6.0   3.3 |  -8.0  17.6  040  23 12   4.3   2.4
 10000  -7.8  18.0  045  29 15   8.6   4.7 |  -7.7  18.1  040  24 12   4.9   2.7
  9750  -7.2  19.0  045  30 15   6.6   3.6 |  -7.3  18.9  035  25 13   4.4   2.4
  9500  -6.8  19.8  040  30 15   5.5   3.0 |  -7.0  19.4  030  26 13   3.9   2.2
  9250  -6.4  20.5  040  30 15   6.8   3.7 |  -6.7  19.9  025  27 14   5.3   2.9
  9000  -5.8  21.6  035  30 15   8.6   4.7 |  -6.2  20.8  020  28 14   7.9   4.3
  8750  -5.2  22.6  030  28 15   8.4   4.6 |  -5.6  21.9  015  27 14   8.3   4.6
  8500  -4.6  23.7  030  27 14   8.4   4.6 |  -5.0  23.0  015  25 13   8.2   4.5
  8250  -4.0  24.8  025  25 13   7.3   4.0 |  -4.4  24.1  010  25 13   7.8   4.3
  8000  -3.5  25.7  020  24 12   8.1   4.4 |  -3.8  25.2  005  24 12  10.9   6.0
  7750  -2.7  27.1  020  19 10  13.2   7.2 |  -2.7  27.1  005  19 10  17.6   9.6
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/14/2024 at 1500 MDT          |       03/14/2024 at 1800 MDT
                                           |
CAPE...   +18.3    LI...       +0.6        | CAPE...    +8.1    LI...       +0.8
CINH...     0.0    K Index... +19.0        | CINH...     0.0    K Index... +17.1
                                           |
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 -54.0 -65.2  250  18  9   1.3   0.7 | -54.5 -66.1  260  19 10   1.1   0.6
 45000 -52.0 -61.6  245  20 10   1.3   0.7 | -52.8 -63.0  255  24 12   1.1   0.6
 40000 -54.0 -65.2  235  35 18  -1.6  -0.9 | -53.9 -65.0  240  36 18  -0.8  -0.5
 38000 -54.8 -66.6  235  42 22   0.5   0.3 | -54.4 -65.9  235  43 22  -1.0  -0.5
 36000 -54.5 -66.1  230  55 28   0.4   0.2 | -55.0 -67.0  230  61 32  -1.0  -0.5
 34000 -54.3 -65.7  230  66 34   0.9   0.5 | -55.6 -68.1  230  78 40   1.6   0.9
 32000 -52.0 -61.6  225  58 30   4.1   2.2 | -51.9 -61.4  230  79 40   6.4   3.5
 30000 -49.5 -57.1  225  49 25   4.5   2.5 | -48.0 -54.4  235  79 41   6.6   3.6
 29000 -48.0 -54.4  215  37 19   5.4   3.0 | -46.0 -50.8  230  69 35   6.7   3.6
 28000 -46.3 -51.3  200  25 13   5.4   3.0 | -44.0 -47.2  230  59 30   6.7   3.6
 27000 -44.7 -48.5  165  19 10   5.4   3.0 | -42.0 -43.6  230  48 25   6.7   3.7
 26000 -42.6 -44.7  145  19 10   8.4   4.6 | -40.1 -40.2  220  35 18   6.2   3.4
 25000 -40.1 -40.2  145  19 10   8.5   4.7 | -38.3 -36.9  195  24 12   6.2   3.4
 24000 -37.5 -35.5  150  20 10   8.5   4.7 | -36.4 -33.5  150  23 12   6.2   3.4
 23000 -34.8 -30.6  150  20 10   9.5   5.2 | -34.2 -29.6  130  27 14   8.5   4.7
 22000 -32.0 -25.6  150  21 11   9.6   5.3 | -31.6 -24.9  130  27 14   8.6   4.7
 21000 -29.1 -20.4  155  21 11   9.8   5.4 | -28.4 -19.1  130  26 14   8.2   4.5
 20000 -26.0 -14.8  145  19 10   8.0   4.4 | -26.1 -15.0  125  26 13   7.7   4.2
 19500 -24.8 -12.6  140  18  9   8.0   4.4 | -25.0 -13.0  125  25 13   7.7   4.2
 19000 -23.7 -10.7  130  18  9   8.0   4.4 | -23.9 -11.0  125  25 13   7.7   4.2
 18500 -22.5  -8.5  125  17  9   7.5   4.1 | -22.7  -8.9  125  24 13   7.6   4.2
 18000 -21.5  -6.7  120  16  8   6.5   3.6 | -21.6  -6.9  125  24 12   7.6   4.2
 17500 -20.5  -4.9  115  15  8   6.5   3.5 | -20.5  -4.9  125  23 12   7.7   4.2
 17000 -19.5  -3.1  115  15  8   7.4   4.1 | -19.4  -2.9  120  23 12   7.0   3.9
 16500 -18.4  -1.1  115  15  8   7.4   4.0 | -18.3  -0.9  120  22 11   7.1   3.9
 16000 -17.3   0.9  115  16  8   7.8   4.3 | -17.3   0.9  115  22 11   6.8   3.7
 15500 -16.1   3.0  110  17  9   8.0   4.4 | -16.3   2.7  115  21 11   6.7   3.7
 15000 -14.9   5.2  110  18  9   8.0   4.4 | -15.3   4.5  110  21 11   6.9   3.8
 14500 -13.8   7.2  110  19 10   8.0   4.4 | -14.3   6.3  105  22 11   7.0   3.9
 14000 -12.6   9.3  105  20 10   7.4   4.1 | -13.2   8.2  100  23 12   7.3   4.0
 13500 -11.7  10.9  100  19 10   5.2   2.9 | -12.1  10.2  100  23 12   7.9   4.3
 13000 -11.0  12.2  090  18  9   5.2   2.9 | -11.0  12.2  100  24 12   7.7   4.2
 12500 -10.3  13.5  085  18  9   4.3   2.3 |  -9.9  14.2  095  24 12   5.6   3.1
 12000  -9.6  14.7  070  17  9   4.2   2.3 |  -9.3  15.3  085  21 11   3.8   2.1
 11750  -9.3  15.3  060  17  9   3.7   2.0 |  -9.1  15.6  085  20 11   1.9   1.0
 11500  -9.1  15.6  060  18  9   3.3   1.8 |  -9.0  15.8  080  20 10   1.2   0.7
 11250  -8.9  16.0  055  19 10   2.7   1.5 |  -8.8  16.2  075  20 10   2.8   1.5
 11000  -8.7  16.3  050  20 10   2.3   1.3 |  -8.6  16.5  070  20 10   2.8   1.5
 10750  -8.5  16.7  045  21 11   2.6   1.4 |  -8.5  16.7  065  20 10   1.0   0.6
 10500  -8.3  17.1  040  20 11   2.4   1.3 |  -8.4  16.9  060  21 11   0.4   0.2
 10250  -8.1  17.4  035  21 11   3.2   1.8 |  -8.4  16.9  055  22 11   1.2   0.6
 10000  -7.8  18.0  035  21 11   4.4   2.4 |  -8.2  17.2  050  22 11   2.9   1.6
  9750  -7.5  18.5  030  23 12   4.5   2.5 |  -7.9  17.8  040  22 11   3.9   2.1
  9500  -7.2  19.0  025  24 12   4.0   2.2 |  -7.7  18.1  030  21 11   3.7   2.0
  9250  -6.9  19.6  020  26 13   5.8   3.2 |  -7.4  18.7  020  22 11   4.2   2.3
  9000  -6.3  20.7  015  28 14   8.3   4.6 |  -7.0  19.4  010  23 12   6.9   3.8
  8750  -5.7  21.7  010  27 14   8.2   4.5 |  -6.4  20.5  005  22 11   8.4   4.6
  8500  -5.1  22.8  010  26 13   8.6   4.7 |  -5.8  21.6  360  22 11   8.1   4.4
  8250  -4.5  23.9  005  25 13   7.2   4.0 |  -5.2  22.6  355  22 11   7.9   4.3
  8000  -4.0  24.8  360  25 13  10.8   5.9 |  -4.7  23.5  355  21 11   8.7   4.7
  7750  -2.8  27.0  360  20 10  20.5  11.3 |  -4.0  24.8  350  16  8  10.9   6.0
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     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 the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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


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