Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281204
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0604 MDT Thursday, March 28, 2024

This forecast is for the Air Force Academy for Thursday, March 28, 2024:

If the trigger temperature of 47.1 F/8.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 758 ft/min (3.9 m/s)
   Maximum height of thermals.................. 18120 ft MSL (10534 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1115 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................. 14029 ft MSL (6443 ft AGL)
Thermal soaring outlook for Friday 03/29....... Good

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

Remarks...

Sunrise/Sunset.................... 06:48:44 / 19:19:25 MDT
Total possible sunshine........... 12 hr 30 min 41 sec (750 min 41 sec)
Altitude of sun at 13:04:05 MDT... 54.41 degrees

Upper air data from numerical model forecast valid on 03/28/2024 at 0600 MDT

Freezing level.................. 8037 ft MSL (451 ft AGL)
Additional freezing level....... 9734 ft MSL (2148 ft AGL)
Convective condensation level... 18330 ft MSL (10744 ft AGL)
Lifted condensation level....... 18431 ft MSL (10845 ft AGL)
Lifted index.................... +1.3
K index......................... +2.6

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  -58.6 -73.5   270   58   30  -0.0  -0.0      M     M       M      M    M
 45000  -58.7 -73.7   275   69   36  -0.2  -0.1      M     M       M      M    M
 40000  -64.5 -84.1   275   73   38  -4.3  -2.4      M     M       M      M    M
 38000  -64.3 -83.7   275   75   38   7.6   4.2      M     M       M      M    M
 36000  -59.8 -75.6   275   76   39   7.5   4.1      M     M       M      M    M
 34000  -55.2 -67.4   280   77   39   8.5   4.7      M     M       M      M    M
 32000  -50.1 -58.2   280   73   38   8.4   4.6      M     M       M      M    M
 30000  -45.1 -49.2   285   69   36   7.6   4.2   23.6  74.5     7.0      M    M
 29000  -42.8 -45.0   285   66   34   7.7   4.2   22.7  72.9     6.4      M    M
 28000  -40.5 -40.9   285   63   32   7.7   4.2   21.9  71.5     5.9      M    M
 27000  -38.2 -36.8   285   60   31   7.7   4.2   21.3  70.3     5.4      M    M
 26000  -35.9 -32.6   285   56   29   7.8   4.3   20.5  68.8     4.8      M    M
 25000  -33.5 -28.3   285   53   27   7.8   4.3   19.7  67.5     4.3      M    M
 24000  -31.2 -24.2   285   49   25   7.9   4.3   19.1  66.4     3.8      M    M
 23000  -28.8 -19.8   285   46   24   7.8   4.3   18.4  65.1     3.3      M    M
 22000  -25.9 -14.6   280   43   22   7.8   4.3   17.5  63.6     2.6      M    M
 21000  -23.6 -10.5   280   40   21   7.5   4.1   16.9  62.4     2.0      M    M
 20000  -21.3  -6.3   285   38   19   7.5   4.1   16.0  60.9     1.3      M    M
 19500  -20.2  -4.4   285   37   19   7.5   4.1   15.6  60.2     1.0      M    M
 19000  -19.1  -2.4   285   35   18   7.5   4.1   15.3  59.5     0.7      M    M
 18500  -18.0  -0.4   285   34   18   6.8   3.7   14.9  58.8     0.3      M    M
 18000  -17.1   1.2   285   33   17   6.5   3.6   14.3  57.8    -0.2    942  4.8
 17500  -16.1   3.0   285   32   17   6.7   3.7   13.8  56.9    -0.7    899  4.6
 17000  -15.0   5.0   290   32   16   7.3   4.0   13.4  56.1    -1.1    852  4.3
 16500  -14.0   6.8   290   31   16   7.2   4.0   13.0  55.3    -1.5    805  4.1
 16000  -12.8   9.0   290   30   16   8.1   4.4   12.6  54.7    -1.8    756  3.8
 15500  -11.6  11.1   290   30   15   8.1   4.4   12.3  54.2    -2.1    705  3.6
 15000  -10.4  13.3   290   29   15   7.8   4.3   12.1  53.7    -2.4    654  3.3
 14500   -9.3  15.3   295   29   15   7.7   4.2   11.7  53.1    -2.7    605  3.1
 14000   -8.1  17.4   295   28   14   7.5   4.1   11.4  52.5    -3.0    555  2.8
 13500   -7.0  19.4   295   27   14   7.2   4.0   11.0  51.8    -3.4    508  2.6
 13000   -5.9  21.4   295   25   13   7.1   3.9   10.6  51.1    -3.8    461  2.3
 12500   -5.0  23.0   295   24   12   5.7   3.1   10.1  50.1    -4.4    418  2.1
 12000   -4.2  24.4   295   20   10   5.3   2.9    9.4  48.9    -5.0    378  1.9
 11750   -3.8  25.2   300   19   10   4.2   2.3    9.0  48.2    -5.4    360  1.8
 11500   -3.5  25.7   300   17    9   4.8   2.6    8.6  47.5    -5.9    344  1.7
 11250   -3.1  26.4   300   15    8   6.3   3.4    8.3  46.9    -6.2    324  1.6
 11000   -2.6  27.3   305   13    7   6.6   3.6    8.0  46.4    -6.5    302  1.5
 10750   -2.1  28.2   310   13    7   6.8   3.7    7.8  46.0    -6.7    280  1.4
 10500   -1.6  29.1   310   14    7   6.8   3.7    7.6  45.6    -7.0    257  1.3
 10250   -1.1  30.0   315   16    8   7.2   4.0    7.3  45.2    -7.2    235  1.2
 10000   -0.6  30.9   315   17    9   6.9   3.8    7.1  44.9    -7.4    211  1.1
  9750   -0.1  31.8   310   19   10   5.7   3.1    6.9  44.4    -7.7    190  1.0
  9500    0.3  32.5   310   19   10   5.9   3.2    6.6  43.8    -8.1    170  0.9
  9250    0.7  33.3   310   20   10   5.2   2.8    6.2  43.2    -8.4    150  0.8
  9000    1.0  33.8   310   21   11   2.7   1.5    5.8  42.5    -8.8    134  0.7
  8750    1.1  34.0   305   20   11   0.9   0.5    5.2  41.3    -9.5    123  0.6
  8500    1.3  34.3   300   20   11   3.5   1.9    4.6  40.2   -10.1    111  0.6
  8250    1.4  34.5   295   21   11  -4.9  -2.7    4.0  39.1   -10.8    100  0.5
  8000    0.3  32.5   295   21   11 -21.4 -11.8    2.2  35.9   -12.6    125  0.6
  7750   -1.5  29.3   290   14    7 -23.9 -13.1   -0.4  31.3   -15.2    173  0.9
  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 * * * * * *

           03/28/2024 at 0900 MDT          |       03/28/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +2.8        | CAPE...     0.0    LI...       +2.9
CINH...     0.0    K Index...  +0.4        | CINH...     0.0    K Index...  +3.8
                                           |
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 -58.7 -73.7  265  57 30  -1.2  -0.7 | -58.9 -74.0  265  57 29  -1.6  -0.9
 45000 -60.5 -76.9  270  74 38  -1.3  -0.7 | -61.4 -78.5  265  76 39  -1.6  -0.9
 40000 -64.6 -84.3  270  78 40  -2.7  -1.5 | -63.6 -82.5  270  80 41  -1.4  -0.8
 38000 -63.7 -82.7  270  78 40   6.7   3.7 | -62.7 -80.9  270  79 41   5.3   2.9
 36000 -59.7 -75.5  275  78 40   6.7   3.7 | -59.6 -75.3  265  76 39   5.2   2.9
 34000 -55.6 -68.1  275  77 40   8.3   4.6 | -56.1 -69.0  265  73 38   9.1   5.0
 32000 -50.7 -59.3  275  72 37   8.1   4.5 | -50.9 -59.6  265  70 36   8.7   4.8
 30000 -45.9 -50.6  275  67 34   7.4   4.1 | -45.7 -50.3  265  66 34   8.2   4.5
 29000 -43.6 -46.5  275  65 33   7.5   4.1 | -43.3 -45.9  265  64 33   8.2   4.5
 28000 -41.4 -42.5  275  62 32   7.5   4.1 | -40.8 -41.4  265  62 32   8.2   4.5
 27000 -39.1 -38.4  275  60 31   7.6   4.2 | -38.3 -36.9  265  60 31   8.2   4.5
 26000 -36.7 -34.1  275  57 29   8.1   4.4 | -36.0 -32.8  265  58 30   7.8   4.3
 25000 -34.3 -29.7  270  53 27   8.1   4.5 | -33.7 -28.7  265  55 28   7.8   4.3
 24000 -31.9 -25.4  270  50 26   8.1   4.4 | -30.8 -23.4  265  52 27   8.1   4.4
 23000 -28.6 -19.5  270  48 25   8.9   4.9 | -28.3 -18.9  265  48 25   8.3   4.5
 22000 -25.9 -14.6  270  46 24   8.9   4.9 | -25.8 -14.4  265  43 22   8.3   4.5
 21000 -23.3  -9.9  270  44 23   6.9   3.8 | -23.4 -10.1  265  40 20   8.0   4.4
 20000 -21.3  -6.3  270  40 21   6.9   3.8 | -21.0  -5.8  265  38 20   8.0   4.4
 19500 -20.2  -4.4  270  39 20   6.9   3.8 | -19.8  -3.6  265  37 19   8.0   4.4
 19000 -19.2  -2.6  270  37 19   6.9   3.8 | -18.6  -1.5  265  36 19   8.0   4.4
 18500 -18.2  -0.8  270  35 18   7.5   4.1 | -17.4   0.7  270  36 18   7.9   4.3
 18000 -17.0   1.4  270  34 17   7.6   4.2 | -16.2   2.8  270  36 19   7.8   4.3
 17500 -15.9   3.4  275  33 17   7.6   4.2 | -15.1   4.8  270  37 19   7.7   4.2
 17000 -14.8   5.4  275  32 16   7.6   4.2 | -13.9   7.0  270  36 19   7.3   4.0
 16500 -13.6   7.5  275  30 16   7.6   4.1 | -12.8   9.0  265  35 18   7.3   4.0
 16000 -12.5   9.5  280  29 15   8.0   4.4 | -11.7  10.9  265  33 17   7.8   4.3
 15500 -11.3  11.7  280  28 14   8.0   4.4 | -10.5  13.1  265  32 16   7.8   4.3
 15000 -10.1  13.8  280  27 14   7.8   4.3 |  -9.4  15.1  265  31 16   7.0   3.9
 14500  -8.9  16.0  280  25 13   7.6   4.2 |  -8.4  16.9  265  29 15   6.6   3.6
 14000  -7.8  18.0  285  23 12   7.0   3.8 |  -7.4  18.7  265  28 14   6.6   3.6
 13500  -6.9  19.6  285  21 11   6.3   3.4 |  -6.4  20.5  265  26 13   6.7   3.7
 13000  -5.9  21.4  285  18  9   6.9   3.8 |  -5.4  22.3  265  24 12   7.7   4.2
 12500  -4.9  23.2  285  17  9   6.5   3.5 |  -4.4  24.1  265  23 12   4.8   2.7
 12000  -4.0  24.8  285  14  7   6.7   3.7 |  -3.8  25.2  265  20 10   4.5   2.5
 11750  -3.4  25.9  285  13  7   8.0   4.4 |  -3.4  25.9  265  19 10   4.7   2.6
 11500  -2.8  27.0  290  13  7   8.1   4.5 |  -3.1  26.4  265  19 10   5.1   2.8
 11250  -2.2  28.0  290  13  7   8.1   4.5 |  -2.7  27.1  265  17  9   5.5   3.0
 11000  -1.6  29.1  295  14  7   7.1   3.9 |  -2.4  27.7  260  16  8   5.3   2.9
 10750  -1.2  29.8  295  14  7   5.3   2.9 |  -2.0  28.4  260  15  7   4.6   2.5
 10500  -0.8  30.6  295  14  7   4.8   2.6 |  -1.7  28.9  255  13  7   3.9   2.1
 10250  -0.5  31.1  300  14  7   5.4   2.9 |  -1.4  29.5  245  11  6   6.9   3.8
 10000  -0.1  31.8  300  13  7   5.4   3.0 |  -0.8  30.6  235  10  5   9.0   5.0
  9750   0.3  32.5  300  12  6   4.8   2.6 |  -0.2  31.6  225   9  5   8.0   4.4
  9500   0.6  33.1  300  11  6   5.1   2.8 |   0.4  32.7  210   9  5   7.6   4.2
  9250   1.0  33.8  300   9  5   4.1   2.2 |   1.0  33.8  200   9  5   9.1   5.0
  9000   1.2  34.2  300   8  4   4.4   2.4 |   1.8  35.2  190   9  5  10.7   5.8
  8750   1.6  34.9  300   8  4   5.0   2.7 |   2.5  36.5  185   9  5  10.1   5.5
  8500   2.0  35.6  295   7  4   6.4   3.5 |   3.3  37.9  185   9  5  10.0   5.5
  8250   2.4  36.3  295   7  4   0.1   0.1 |   4.0  39.2  180   9  5  10.2   5.6
  8000   2.0  35.6  290   8  4  -4.0  -2.2 |   4.9  40.8  180   9  5  14.1   7.7
  7750   2.1  35.8  280   6  3   8.2   4.5 |   6.1  43.0  180   9  5  19.7  10.8
  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

           03/28/2024 at 1500 MDT          |       03/28/2024 at 1800 MDT
                                           |
CAPE...   +11.0    LI...       +1.2        | CAPE...   +63.0    LI...       -0.4
CINH...   -16.0    K Index... +12.4        | CINH...   -18.6    K Index... +13.6
                                           |
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 -59.3 -74.7  265  57 29  -1.0  -0.6 | -61.0 -77.8  260  60 31  -0.6  -0.4
 45000 -60.8 -77.4  270  76 39  -1.0  -0.6 | -62.0 -79.6  265  73 38  -0.7  -0.4
 40000 -62.4 -80.3  270  89 46  -1.0  -0.6 | -62.2 -80.0  270  89 46  -0.1  -0.0
 38000 -61.5 -78.7  270  90 46   4.7   2.6 | -60.6 -77.1  270  94 48   5.7   3.1
 36000 -58.7 -73.7  265  84 43   4.6   2.5 | -57.2 -71.0  270  95 49   5.7   3.1
 34000 -55.6 -68.1  265  79 40   8.9   4.9 | -53.7 -64.7  270  95 49   6.9   3.8
 32000 -50.5 -58.9  260  73 38   8.4   4.6 | -49.6 -57.3  265  88 45   6.8   3.7
 30000 -45.4 -49.7  260  68 35   8.6   4.7 | -45.3 -49.5  265  79 41   9.0   4.9
 29000 -42.9 -45.2  260  67 35   8.6   4.7 | -42.7 -44.9  265  71 37   8.9   4.9
 28000 -40.3 -40.5  260  67 34   8.6   4.7 | -40.0 -40.0  260  64 33   8.9   4.9
 27000 -37.7 -35.9  260  66 34   8.5   4.6 | -37.4 -35.3  260  56 29   8.8   4.8
 26000 -35.3 -31.5  260  65 33   7.7   4.2 | -35.0 -31.0  260  57 30   7.9   4.3
 25000 -33.0 -27.4  260  64 33   7.7   4.2 | -32.6 -26.7  265  60 31   7.9   4.3
 24000 -30.7 -23.3  260  63 32   7.7   4.2 | -30.3 -22.5  265  64 33   7.9   4.4
 23000 -27.8 -18.0  260  57 29   7.9   4.4 | -27.5 -17.5  265  57 30   7.2   4.0
 22000 -25.4 -13.7  255  52 27   8.0   4.4 | -25.3 -13.5  265  50 26   7.2   4.0
 21000 -23.0  -9.4  255  47 24   8.5   4.7 | -23.2  -9.8  260  45 23   7.4   4.1
 20000 -20.4  -4.7  255  45 23   8.6   4.7 | -20.9  -5.6  265  48 25   7.5   4.1
 19500 -19.2  -2.6  260  44 22   8.6   4.7 | -19.8  -3.6  265  50 26   7.5   4.1
 19000 -17.9  -0.2  260  42 22   8.6   4.7 | -18.7  -1.7  265  51 26   7.5   4.1
 18500 -16.6   2.1  265  42 22   8.0   4.4 | -17.6   0.3  265  53 27   7.4   4.0
 18000 -15.5   4.1  265  44 23   7.8   4.3 | -16.5   2.3  265  53 27   7.3   4.0
 17500 -14.3   6.3  265  46 24   7.6   4.1 | -15.5   4.1  265  52 27   7.4   4.0
 17000 -13.3   8.1  265  47 24   6.0   3.3 | -14.3   6.3  265  51 26   7.7   4.2
 16500 -12.4   9.7  265  48 25   6.1   3.3 | -13.2   8.2  265  48 25   7.8   4.3
 16000 -11.4  11.5  265  47 24   6.7   3.7 | -12.1  10.2  265  45 23   6.6   3.6
 15500 -10.4  13.3  265  45 23   6.7   3.7 | -11.1  12.0  260  41 21   6.5   3.6
 15000  -9.5  14.9  265  43 22   6.2   3.4 | -10.1  13.8  255  38 19   7.0   3.9
 14500  -8.6  16.5  265  43 22   5.9   3.2 |  -9.0  15.8  260  39 20   7.5   4.1
 14000  -7.7  18.1  265  43 22   6.1   3.4 |  -7.9  17.8  260  41 21   7.9   4.3
 13500  -6.8  19.8  260  38 19   6.9   3.8 |  -6.7  19.9  260  37 19   8.9   4.9
 13000  -5.9  21.4  255  32 17   9.7   5.3 |  -5.5  22.1  255  33 17  11.8   6.5
 12500  -4.4  24.1  250  29 15   7.8   4.3 |  -3.9  25.0  255  31 16   7.8   4.3
 12000  -3.3  26.1  245  24 13   8.1   4.4 |  -2.6  27.3  250  27 14   8.4   4.6
 11750  -2.6  27.3  245  23 12   9.0   5.0 |  -2.0  28.4  250  26 13   9.5   5.2
 11500  -1.9  28.6  240  22 11   9.5   5.2 |  -1.3  29.7  250  25 13   9.9   5.4
 11250  -1.2  29.8  240  21 11   9.5   5.2 |  -0.6  30.9  250  25 13   9.5   5.2
 11000  -0.5  31.1  235  20 10   9.3   5.1 |   0.1  32.2  245  24 12   9.5   5.2
 10750   0.1  32.2  235  20 10   8.2   4.5 |   0.8  33.4  245  23 12   8.6   4.7
 10500   0.7  33.3  230  19 10   7.7   4.2 |   1.4  34.5  245  22 11   8.1   4.5
 10250   1.4  34.5  225  18  9  10.3   5.6 |   2.1  35.8  245  22 11   9.9   5.5
 10000   2.2  36.0  225  18  9  11.4   6.3 |   2.9  37.2  240  21 11  10.6   5.8
  9750   3.0  37.4  225  17  9   9.8   5.4 |   3.6  38.5  240  20 10   9.1   5.0
  9500   3.7  38.7  220  16  8   9.5   5.2 |   4.2  39.6  240  20 10   8.2   4.5
  9250   4.4  39.9  220  16  8   9.4   5.2 |   4.9  40.8  235  19 10   9.7   5.3
  9000   5.1  41.2  215  15  8   9.7   5.3 |   5.7  42.3  235  18  9  10.9   6.0
  8750   5.8  42.4  215  15  8  10.3   5.7 |   6.4  43.5  230  17  9   9.3   5.1
  8500   6.6  43.9  215  15  7  10.9   6.0 |   7.1  44.8  230  16  8   8.5   4.7
  8250   7.4  45.3  210  14  7   9.2   5.1 |   7.7  45.9  230  16  8   9.5   5.2
  8000   8.1  46.6  205  13  7  11.0   6.0 |   8.3  46.9  225  15  8   4.2   2.3
  7750   9.1  48.4  205  12  6  18.7  10.3 |   8.1  46.6  220  11  6  -7.3  -4.0
  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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