Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 121207
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0607 MDT Tuesday, March 12, 2024

This forecast is for the Air Force Academy for Tuesday, March 12, 2024:

If the trigger temperature of 42.9 F/6.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1398 ft/min (7.1 m/s)
   Maximum height of thermals.................. 22704 ft MSL (15068 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 0900 MDT
Time of overdevelopment........................ 1200 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 20606 ft MSL (12970 ft AGL)
Thermal soaring outlook for Wednesday 03/13.... Fair

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

Remarks...

Sunrise/Sunset.................... 07:13:53 / 19:03:41 MDT
Total possible sunshine........... 11 hr 49 min 48 sec (709 min 48 sec)
Altitude of sun at 13:08:47 MDT... 48.07 degrees

Upper air data from numerical model forecast valid on 03/12/2024 at 0600 MDT

Freezing level.................. 9277 ft MSL (1641 ft AGL)
Convective condensation level... 14728 ft MSL (7092 ft AGL)
Lifted condensation level....... 18108 ft MSL (10472 ft AGL)
Lifted index.................... -1.5
K index......................... +4.5

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -57.1 -70.8   260   26   13   2.0   1.1      M     M       M      M    M
 45000  -54.0 -65.2   270   35   18   2.3   1.3      M     M       M      M    M
 40000  -56.8 -70.2   285   38   19  -2.2  -1.2      M     M       M      M    M
 38000  -57.4 -71.3   295   39   20   2.0   1.1      M     M       M      M    M
 36000  -56.1 -69.0   310   43   22   2.1   1.2      M     M       M      M    M
 34000  -54.5 -66.1   325   51   26   5.7   3.1      M     M       M      M    M
 32000  -50.5 -58.9   335   53   28   6.7   3.7      M     M       M      M    M
 30000  -46.4 -51.5   340   57   29   8.0   4.4   22.4  72.3     4.8      M    M
 29000  -44.0 -47.2   340   58   30   8.1   4.5   21.6  70.9     4.3      M    M
 28000  -41.6 -42.9   340   58   30   8.1   4.5   21.0  69.7     3.8      M    M
 27000  -39.1 -38.4   335   59   30   8.2   4.5   20.5  68.8     3.5      M    M
 26000  -36.8 -34.2   335   56   29   7.7   4.2   19.7  67.5     2.9      M    M
 25000  -34.5 -30.1   330   52   27   7.7   4.2   18.9  66.0     2.3      M    M
 24000  -32.2 -26.0   320   49   25   7.7   4.2   18.2  64.7     1.7      M    M
 23000  -30.4 -22.7   320   43   22   4.9   2.7   16.9  62.3     0.6      M    M
 22000  -28.6 -19.5   315   34   17   4.9   2.7   14.7  58.4    -1.2   1337  6.8
 21000  -27.1 -16.8   310   27   14   5.5   3.0   13.1  55.5    -2.6   1264  6.4
 20000  -25.3 -13.5   305   23   12   6.2   3.4   11.7  53.1    -3.8   1179  6.0
 19500  -24.4 -11.9   300   22   11   6.2   3.4   11.1  52.0    -4.4   1137  5.8
 19000  -23.4 -10.1   295   20   10   6.3   3.5   10.6  51.0    -4.9   1094  5.6
 18500  -22.5  -8.5   295   19   10   7.0   3.9   10.0  50.0    -5.5   1052  5.3
 18000  -21.3  -6.3   290   19   10   8.3   4.6    9.7  49.5    -5.8   1001  5.1
 17500  -20.1  -4.2   290   19   10   8.4   4.6    9.5  49.1    -6.0    950  4.8
 17000  -18.9  -2.0   290   20   10   8.1   4.4    9.2  48.6    -6.3    899  4.6
 16500  -17.7   0.1   290   20   11   8.1   4.5    9.0  48.1    -6.6    848  4.3
 16000  -16.5   2.3   290   21   11   8.0   4.4    8.7  47.6    -6.9    798  4.1
 15500  -15.3   4.5   290   22   12   7.9   4.4    8.4  47.1    -7.3    748  3.8
 15000  -14.2   6.4   290   24   12   7.9   4.4    8.1  46.6    -7.6    698  3.5
 14500  -13.0   8.6   290   25   13   7.9   4.4    7.8  46.0    -7.9    648  3.3
 14000  -11.8  10.8   295   26   13   8.0   4.4    7.5  45.5    -8.2    598  3.0
 13500  -10.6  12.9   295   27   14   8.5   4.7    7.3  45.1    -8.5    546  2.8
 13000   -9.3  15.3   295   29   15   9.1   5.0    7.1  44.7    -8.8    494  2.5
 12500   -7.9  17.8   295   30   15   7.9   4.4    7.0  44.7    -8.9    437  2.2
 12000   -6.9  19.6   295   33   17   6.9   3.8    6.6  43.8    -9.4    392  2.0
 11750   -6.4  20.5   295   34   17   8.5   4.6    6.4  43.5    -9.6    369  1.9
 11500   -5.7  21.7   295   34   18   9.0   4.9    6.3  43.4    -9.7    341  1.7
 11250   -5.1  22.8   295   35   18   7.8   4.3    6.2  43.2    -9.8    316  1.6
 11000   -4.5  23.9   295   35   18   7.8   4.3    6.1  42.9   -10.0    292  1.5
 10750   -4.0  24.8   295   34   17   8.1   4.4    5.9  42.7   -10.2    267  1.4
 10500   -3.4  25.9   300   31   16   8.0   4.4    5.8  42.4   -10.4    242  1.2
 10250   -2.7  27.1   300   29   15   8.9   4.9    5.7  42.2   -10.5    216  1.1
 10000   -2.0  28.4   300   27   14   9.5   5.2    5.7  42.2   -10.6    188  1.0
  9750   -1.4  29.5   300   26   13   8.4   4.6    5.6  42.1   -10.7    160  0.8
  9500   -0.8  30.6   300   25   13   8.0   4.4    5.5  41.8   -10.8    135  0.7
  9250   -0.2  31.6   300   24   12   8.4   4.6    5.4  41.6   -11.0    110  0.6
  9000    0.4  32.7   300   23   12   7.1   3.9    5.2  41.4   -11.1     85  0.4
  8750    0.8  33.4   300   22   11   5.7   3.1    4.9  40.9   -11.5     64  0.3
  8500    1.2  34.2   300   21   11   4.3   2.4    4.6  40.3   -11.9     46  0.2
  8250    2.2  36.0   300   19   10   0.1   0.0    4.1  39.5   -12.4      2  0.0
  8000    1.1  34.0   295   13    6 -27.7 -15.2    2.3  36.2   -14.3     27  0.1
  7750    0.0  32.0   280    7    4  25.5  14.0    0.5  33.0   -16.1     52  0.3
  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 * * * * * *

           03/12/2024 at 0900 MDT          |       03/12/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +5.2        | CAPE...     0.0    LI...       +4.7
CINH...     0.0    K Index... -18.2        | CINH...     0.0    K Index... -14.9
                                           |
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 -57.2 -71.0  260  29 15   2.1   1.2 | -57.5 -71.5  265  29 15   0.9   0.5
 45000 -54.0 -65.2  265  34 18   2.7   1.5 | -56.2 -69.2  265  33 17   1.2   0.6
 40000 -60.5 -76.9  285  54 28  -4.8  -2.6 | -59.7 -75.5  270  49 25  -2.5  -1.4
 38000 -61.8 -79.2  290  58 30   3.6   2.0 | -60.2 -76.4  275  53 27   2.2   1.2
 36000 -59.3 -74.7  300  50 26   3.7   2.1 | -58.7 -73.7  275  51 26   2.3   1.2
 34000 -56.7 -70.1  310  44 23   9.3   5.1 | -56.9 -70.4  270  50 26   9.7   5.3
 32000 -51.3 -60.3  310  42 22   9.0   5.0 | -51.6 -60.9  275  48 25   8.8   4.8
 30000 -46.0 -50.8  310  41 21   8.2   4.5 | -46.3 -51.3  275  46 24   8.7   4.8
 29000 -43.5 -46.3  310  42 21   8.3   4.5 | -43.7 -46.7  280  44 23   8.8   4.8
 28000 -41.0 -41.8  310  43 22   8.3   4.5 | -41.0 -41.8  280  43 22   8.8   4.8
 27000 -38.5 -37.3  310  44 22   8.3   4.5 | -38.4 -37.1  285  41 21   8.7   4.8
 26000 -36.1 -33.0  310  44 22   8.1   4.4 | -35.9 -32.6  285  38 19   8.4   4.6
 25000 -33.7 -28.7  310  43 22   8.1   4.4 | -33.4 -28.1  280  34 18   8.4   4.6
 24000 -31.3 -24.3  310  43 22   8.1   4.4 | -30.8 -23.4  280  31 16   8.5   4.7
 23000 -28.9 -20.0  310  42 22   8.1   4.4 | -28.4 -19.1  280  30 16   7.9   4.3
 22000 -26.4 -15.5  305  41 21   8.1   4.4 | -25.5 -13.9  280  30 16   7.9   4.4
 21000 -23.4 -10.1  305  39 20   7.6   4.2 | -23.1  -9.6  275  31 16   8.0   4.4
 20000 -21.2  -6.2  305  37 19   7.5   4.1 | -20.7  -5.3  275  30 16   8.0   4.4
 19500 -20.0  -4.0  305  36 19   7.5   4.1 | -19.5  -3.1  275  30 16   8.0   4.4
 19000 -18.9  -2.0  305  36 18   7.4   4.1 | -18.3  -0.9  275  30 15   8.0   4.4
 18500 -17.8  -0.0  310  35 18   6.1   3.3 | -17.1   1.2  275  30 15   8.2   4.5
 18000 -17.1   1.2  305  32 16   4.9   2.7 | -15.8   3.6  270  29 15   8.4   4.6
 17500 -16.4   2.5  305  29 15   4.8   2.6 | -14.6   5.7  265  28 14   8.3   4.6
 17000 -15.7   3.7  300  25 13   4.6   2.5 | -13.5   7.7  265  27 14   6.6   3.6
 16500 -15.0   5.0  295  22 11   4.5   2.5 | -12.4   9.7  270  25 13   6.9   3.8
 16000 -14.2   6.4  295  19 10   6.0   3.3 | -11.5  11.3  270  23 12   4.7   2.6
 15500 -13.3   8.1  295  17  9   6.3   3.5 | -10.9  12.4  270  22 11   4.3   2.4
 15000 -12.4   9.7  300  16  8   6.7   3.7 | -10.3  13.5  275  20 10   3.3   1.8
 14500 -11.3  11.7  305  16  8   7.0   3.8 |  -9.9  14.2  275  18  9   2.5   1.3
 14000 -10.3  13.5  310  16  8   7.1   3.9 |  -9.6  14.7  275  17  9   3.2   1.7
 13500  -9.3  15.3  310  18 10   7.3   4.0 |  -8.9  16.0  280  14  7   5.6   3.1
 13000  -8.2  17.2  315  21 11   7.7   4.2 |  -8.1  17.4  290  12  6   7.1   3.9
 12500  -7.2  19.0  310  22 11   5.0   2.7 |  -6.8  19.8  300  11  6   7.6   4.2
 12000  -6.6  20.1  305  24 12   4.4   2.4 |  -5.9  21.4  315  12  6   6.7   3.7
 11750  -6.2  20.8  305  25 13   6.5   3.6 |  -5.4  22.3  315  12  6   7.4   4.0
 11500  -5.7  21.7  305  24 12   7.6   4.1 |  -4.8  23.4  315  12  6   7.5   4.1
 11250  -5.1  22.8  300  23 12   6.9   3.8 |  -4.3  24.3  310  11  6   6.9   3.8
 11000  -4.6  23.7  300  23 12   6.9   3.8 |  -3.8  25.2  305  10  5   7.2   3.9
 10750  -4.1  24.6  300  23 12   6.5   3.6 |  -3.3  26.1  300   9  5   8.0   4.4
 10500  -3.7  25.3  300  25 13   6.3   3.5 |  -2.7  27.1  295   8  4   8.2   4.5
 10250  -3.2  26.2  300  27 14   6.6   3.6 |  -2.1  28.2  285   7  3   9.5   5.2
 10000  -2.7  27.1  300  27 14   7.0   3.8 |  -1.4  29.5  285   6  3  10.6   5.8
  9750  -2.2  28.0  300  26 13   7.1   3.9 |  -0.6  30.9  285   6  3   9.9   5.4
  9500  -1.7  28.9  295  25 13   7.0   3.8 |   0.1  32.2  285   6  3   9.8   5.4
  9250  -1.2  29.8  295  23 12   7.6   4.1 |   0.9  33.6  285   6  3   9.9   5.4
  9000  -0.6  30.9  295  22 11   8.5   4.6 |   1.6  34.9  285   6  3  10.3   5.7
  8750   0.0  32.0  295  20 10   8.5   4.7 |   2.4  36.3  285   5  3  10.4   5.7
  8500   0.6  33.1  290  19 10   8.3   4.6 |   3.2  37.8  285   5  3  11.0   6.0
  8250   1.2  34.2  290  18  9   8.6   4.7 |   4.0  39.2  290   5  3   8.9   4.9
  8000   1.9  35.4  285  16  8  10.6   5.8 |   4.7  40.5  290   5  2  13.9   7.6
  7750   2.8  37.0  285  11  6  13.2   7.2 |   7.8  46.0  290   4  2   1.0   0.5
  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

           03/12/2024 at 1500 MDT          |       03/12/2024 at 1800 MDT
                                           |
CAPE...    +0.2    LI...       +1.5        | CAPE...    +0.3    LI...       +1.0
CINH...    -0.2    K Index...  +4.1        | CINH...    -2.2    K Index... +17.5
                                           |
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 -57.2 -71.0  260  30 15   0.7   0.4 | -56.9 -70.4  265  34 18   0.5   0.3
 45000 -56.2 -69.2  270  43 22   1.0   0.6 | -56.1 -69.0  270  39 20   0.8   0.5
 40000 -59.4 -74.9  270  54 28  -2.3  -1.3 | -59.8 -75.6  265  57 29  -2.7  -1.5
 38000 -59.8 -75.6  265  56 29   2.4   1.3 | -60.4 -76.7  265  62 32   2.7   1.5
 36000 -58.2 -72.8  265  54 28   2.4   1.3 | -58.5 -73.3  265  63 33   2.8   1.5
 34000 -56.3 -69.3  265  53 27   9.4   5.2 | -56.4 -69.5  265  62 32   9.8   5.4
 32000 -51.1 -60.0  260  49 25   8.7   4.7 | -51.0 -59.8  260  49 25   9.0   4.9
 30000 -45.8 -50.4  260  46 24   9.5   5.2 | -45.6 -50.1  255  38 20   9.2   5.0
 29000 -43.0 -45.4  265  45 23   9.5   5.2 | -42.9 -45.2  255  37 19   9.2   5.0
 28000 -40.1 -40.2  265  44 22   9.5   5.2 | -40.1 -40.2  255  35 18   9.2   5.0
 27000 -37.3 -35.1  270  42 22   9.3   5.1 | -37.4 -35.3  250  34 18   9.1   5.0
 26000 -34.9 -30.8  270  43 22   8.0   4.4 | -35.0 -31.0  255  36 18   7.7   4.2
 25000 -32.5 -26.5  265  43 22   8.0   4.4 | -32.7 -26.9  255  38 19   7.7   4.2
 24000 -30.1 -22.2  265  44 23   8.1   4.5 | -30.4 -22.7  255  40 20   7.9   4.3
 23000 -27.9 -18.2  265  42 22   7.0   3.8 | -28.3 -18.9  260  40 21   6.8   3.7
 22000 -25.4 -13.7  260  39 20   7.0   3.8 | -26.3 -15.3  260  41 21   6.8   3.7
 21000 -23.3  -9.9  260  37 19   7.0   3.8 | -23.7 -10.7  265  41 21   7.4   4.1
 20000 -21.2  -6.2  260  34 18   7.0   3.8 | -21.5  -6.7  265  37 19   7.6   4.1
 19500 -20.1  -4.2  255  33 17   7.0   3.8 | -20.4  -4.7  265  36 18   7.6   4.2
 19000 -19.1  -2.4  255  32 16   7.0   3.8 | -19.2  -2.6  270  34 17   7.6   4.1
 18500 -18.0  -0.4  255  30 16   8.2   4.5 | -18.1  -0.6  270  32 16   7.1   3.9
 18000 -16.6   2.1  255  30 16   9.0   5.0 | -17.1   1.2  270  31 16   6.8   3.7
 17500 -15.2   4.6  255  30 16   9.0   5.0 | -16.1   3.0  270  29 15   6.8   3.7
 17000 -14.1   6.6  255  30 15   6.6   3.6 | -15.2   4.6  270  29 15   5.8   3.2
 16500 -13.0   8.6  260  30 15   6.8   3.8 | -14.3   6.3  270  29 15   5.8   3.2
 16000 -12.1  10.2  260  29 15   6.1   3.4 | -13.4   7.9  265  28 15   6.8   3.7
 15500 -11.2  11.8  265  30 15   6.0   3.3 | -12.4   9.7  265  28 14   7.0   3.8
 15000 -10.3  13.5  265  30 15   5.4   3.0 | -11.3  11.7  260  27 14   7.4   4.1
 14500  -9.6  14.7  265  28 14   4.9   2.7 | -10.2  13.6  255  24 12   7.9   4.3
 14000  -8.9  16.0  260  26 13   5.3   2.9 |  -9.0  15.8  250  20 10   8.2   4.5
 13500  -8.1  17.4  255  20 10   6.3   3.5 |  -7.7  18.1  245  18  9   9.3   5.1
 13000  -7.3  18.9  250  14  7   8.1   4.4 |  -6.4  20.5  245  16  8  11.9   6.5
 12500  -6.0  21.2  240  11  6   8.2   4.5 |  -4.8  23.4  240  15  8   7.6   4.2
 12000  -4.8  23.4  230   8  4   7.9   4.3 |  -3.6  25.5  235  14  7   7.8   4.3
 11750  -4.2  24.4  225   8  4   9.1   5.0 |  -3.0  26.6  235  13  7   9.3   5.1
 11500  -3.5  25.7  220   7  4   9.6   5.3 |  -2.3  27.9  230  13  7   9.4   5.1
 11250  -2.8  27.0  215   7  4   9.3   5.1 |  -1.6  29.1  225  13  7   8.2   4.5
 11000  -2.1  28.2  210   7  3   9.3   5.1 |  -1.0  30.2  225  13  6   8.5   4.7
 10750  -1.4  29.5  205   7  3   9.1   5.0 |  -0.4  31.3  220  12  6   8.2   4.5
 10500  -0.7  30.7  200   7  3   8.9   4.9 |   0.2  32.4  215  12  6   8.1   4.4
 10250  -0.0  32.0  200   7  3  10.2   5.6 |   0.9  33.6  210  12  6   9.6   5.3
 10000   0.8  33.4  195   6  3  10.9   6.0 |   1.6  34.9  205  12  6  10.4   5.7
  9750   1.6  34.9  195   6  3   9.9   5.5 |   2.4  36.3  200  12  6   8.9   4.9
  9500   2.3  36.1  190   6  3   9.6   5.2 |   3.0  37.4  195  12  6   8.0   4.4
  9250   3.0  37.4  190   6  3   9.9   5.4 |   3.6  38.5  190  12  6   8.6   4.7
  9000   3.8  38.8  185   6  3  10.3   5.7 |   4.2  39.6  185  12  6   9.4   5.1
  8750   4.5  40.1  185   6  3  10.2   5.6 |   5.0  41.0  180  11  6   9.8   5.4
  8500   5.3  41.5  180   6  3  10.8   5.9 |   5.7  42.3  180  11  6  10.0   5.5
  8250   6.1  43.0  180   6  3   8.6   4.7 |   6.4  43.5  175  11  6   9.5   5.2
  8000   6.7  44.1  180   6  3  11.5   6.3 |   7.1  44.8  170  11  6   9.4   5.2
  7750   8.0  46.4  175   6  3  23.0  12.6 |   7.8  46.0  170  10  5  10.8   5.9
  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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