Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221307
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
706 AM MDT Friday, March 22, 2024

This forecast is for Friday, March 22, 2024:

If the trigger temperature of 56.7 F/13.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 833 ft/min (4.2 m/s)
   Maximum height of thermals.................. 15050 ft MSL (10211 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13333 ft MSL (8494 ft AGL)
Thermal soaring outlook for Saturday 03/23..... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:13:01 / 19:28:27 MDT
Total possible sunshine........... 12 hr 15 min 26 sec (735 min 26 sec)
Altitude of sun at 13:20:44 MDT... 51.64 degrees

Upper air data from rawinsonde observation taken on 03/22/2024 at 0600 MDT

Freezing level.................. 9465 ft MSL (4626 ft AGL)
Convective condensation level... 14999 ft MSL (10160 ft AGL)
Lifted condensation level....... 15236 ft MSL (10397 ft AGL)
Lifted index.................... -0.3
K index......................... -25.4

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  -57.3 -71.1   275   47   24   4.1   2.2  107.8 226.0    49.7      M    M
 45000  -52.9 -63.2   285   63   32   3.6   2.0   90.1 194.3    42.5      M    M
 40000  -57.8 -72.0   290   47   24  -7.0  -3.8   58.9 138.0    25.2      M    M
 38000  -61.1 -78.0   300   53   27  -1.2  -0.7   43.8 110.9    16.0      M    M
 36000  -61.3 -78.3   295   54   28   5.6   3.0   34.9  94.8    10.2      M    M
 34000  -57.1 -70.8   285   40   21   7.7   4.2   32.5  90.6     8.9      M    M
 32000  -52.7 -62.9   300   36   19   6.8   3.7   30.5  86.9     7.6      M    M
 30000  -47.6 -53.7   310   37   19   8.0   4.4   29.4  85.0     7.0      M    M
 29000  -45.2 -49.4   305   36   18   8.1   4.4   28.7  83.7     6.6      M    M
 28000  -42.8 -45.0   305   31   16   8.0   4.4   28.0  82.5     6.1      M    M
 27000  -40.3 -40.5   300   32   16   7.5   4.1   27.5  81.5     5.8      M    M
 26000  -37.9 -36.2   305   30   16   8.1   4.5   26.7  80.1     5.3      M    M
 25000  -35.5 -31.9   305   27   14   8.8   4.8   26.1  78.9     4.8      M    M
 24000  -32.7 -26.9   305   29   15   9.4   5.2   25.9  78.7     4.8      M    M
 23000  -29.8 -21.6   315   28   14   8.7   4.8   25.8  78.5     4.7      M    M
 22000  -27.2 -17.0   310   24   12   7.1   3.9   25.5  77.9     4.5      M    M
 21000  -25.0 -13.0   305   23   12   7.5   4.1   24.6  76.3     3.8      M    M
 20000  -22.1  -7.8   310   28   14   8.2   4.5   23.7  74.7     3.1      M    M
 19500  -20.9  -5.6   305   27   14   8.0   4.4   23.5  74.2     2.9      M    M
 19000  -19.7  -3.5   305   27   14   7.0   3.8   23.1  73.6     2.6      M    M
 18500  -18.4  -1.1   300   26   13   7.5   4.1   22.8  73.1     2.4      M    M
 18000  -17.7   0.1   300   26   13   7.4   4.1   22.0  71.6     1.7      M    M
 17500  -16.3   2.7   290   24   12   8.5   4.6   22.0  71.6     1.7      M    M
 17000  -15.1   4.8   300   24   12   8.1   4.4   21.6  71.0     1.4      M    M
 16500  -13.8   7.2   300   25   13   8.3   4.5   21.4  70.5     1.2      M    M
 16000  -12.6   9.3   290   25   13   8.3   4.5   21.1  70.1     1.0      M    M
 15500  -11.6  11.1   295   28   15   5.0   2.8   20.6  69.1     0.5      M    M
 15000  -10.8  12.6   310   27   14   5.4   2.9   19.9  67.7    -0.1    825  4.2
 14500  -10.0  14.0   300   23   12   4.1   2.2   19.1  66.3    -0.8    788  4.0
 14000   -9.5  14.9   285   20   10   3.7   2.0   18.0  64.5    -1.8    757  3.8
 13500   -9.0  15.8   290   20   10   3.5   1.9   17.1  62.7    -2.7    726  3.7
 13000   -8.2  17.2   290   21   11   6.9   3.8   16.3  61.4    -3.5    689  3.5
 12500   -7.3  18.9   295   22   11   6.7   3.7   15.8  60.4    -4.0    645  3.3
 12000   -6.3  20.7   295   19   10   6.7   3.7   15.3  59.5    -4.5    602  3.1
 11500   -5.4  22.3   290   20   10   6.7   3.7   14.8  58.7    -5.1    558  2.8
 11000   -4.3  24.3   285   20   10   8.9   4.9   14.5  58.0    -5.5    511  2.6
 10500   -2.9  26.8   290   20   10   9.1   5.0   14.4  57.8    -5.6    456  2.3
 10250   -2.2  28.0   295   19   10   9.2   5.0   14.3  57.8    -5.7    428  2.2
 10000   -1.6  29.1   295   17    9   9.3   5.1   14.3  57.7    -5.8    400  2.0
  9750   -0.9  30.4   300   16    8   9.3   5.1   14.2  57.6    -5.8    372  1.9
  9500   -0.2  31.6   300   15    8   9.3   5.1   14.2  57.5    -5.9    344  1.7
  9250    0.5  32.9   300   14    7   9.3   5.1   14.2  57.5    -5.9    315  1.6
  9000    1.2  34.2   305   13    7   9.3   5.1   14.1  57.4    -6.0    287  1.5
  8750    1.9  35.4   310   13    7   9.3   5.1   14.1  57.4    -6.0    259  1.3
  8500    2.6  36.7   310   12    6   9.4   5.1   14.1  57.3    -6.1    231  1.2
  8250    3.3  37.9   315   10    5   9.1   5.0   14.0  57.2    -6.1    203  1.0
  8000    3.9  39.0   325    7    4   8.6   4.7   13.9  57.1    -6.2    176  0.9
  7750    4.6  40.3   330    7    4   8.3   4.5   13.8  56.9    -6.4    150  0.8
  7500    5.2  41.4   340    7    4   8.7   4.8   13.7  56.7    -6.5    124  0.6
  7250    5.9  42.6   345    6    3   9.9   5.5   13.7  56.7    -6.6     96  0.5
  7000    6.5  43.7   355    4    2   7.5   4.1   13.7  56.6    -6.7     69  0.3
  6750    6.9  44.4   005    4    2   5.1   2.8   13.4  56.0    -7.0     50  0.3
  6500    7.3  45.1   015    3    2   5.9   3.2   13.0  55.5    -7.4     31  0.2
  6250    7.7  45.9   020    3    1   5.4   3.0   12.7  54.9    -7.8     12  0.1
  6000    8.1  46.6   350    2    1   6.8   3.7   12.4  54.4    -8.1      M    M
  5750    8.5  47.3   355    2    1   2.0   1.1   12.1  53.8    -8.5      M    M
  5500    8.2  46.8   295    1    1  -7.3  -4.0   11.1  52.0    -9.5      M    M
  5250    7.6  45.7   210    3    2  -8.5  -4.7    9.7  49.5   -10.9      M    M
  5000    6.9  44.4   200    6    3 -10.4  -5.7    8.4  47.1   -12.3      M    M

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

           03/22/2024 at 0900 MDT          |       03/22/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.1        | CAPE...     0.0    LI...       +3.2
CINH...    -0.1    K Index...  -6.6        | CINH...    -0.2    K Index...  -8.8
                                           |
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 -57.1 -70.8  285  54 28   1.5   0.8 | -57.4 -71.3  280  56 29   1.3   0.7
 45000 -54.8 -66.6  285  63 33   1.8   1.0 | -55.5 -67.9  280  67 35   1.6   0.9
 40000 -59.1 -74.4  290  54 28  -3.0  -1.6 | -59.0 -74.2  280  55 29  -2.4  -1.3
 38000 -59.7 -75.5  290  50 26   1.5   0.8 | -59.5 -75.1  280  51 26   1.4   0.7
 36000 -58.8 -73.8  290  46 24   1.5   0.8 | -58.7 -73.7  280  47 24   1.3   0.7
 34000 -57.5 -71.5  290  42 22   8.3   4.6 | -57.4 -71.3  285  43 22   8.3   4.6
 32000 -52.8 -63.0  290  39 20   7.9   4.3 | -52.9 -63.2  285  40 20   7.6   4.2
 30000 -48.1 -54.6  290  36 18   8.0   4.4 | -48.2 -54.8  285  37 19   8.7   4.8
 29000 -45.6 -50.1  290  35 18   8.0   4.4 | -45.6 -50.1  285  36 18   8.6   4.7
 28000 -43.2 -45.8  290  35 18   8.0   4.4 | -43.0 -45.4  285  35 18   8.6   4.7
 27000 -40.8 -41.4  290  35 18   8.2   4.5 | -40.5 -40.9  285  34 17   8.5   4.6
 26000 -38.2 -36.8  290  34 17   8.7   4.8 | -38.0 -36.4  285  33 17   8.0   4.4
 25000 -35.6 -32.1  290  33 17   8.7   4.8 | -35.6 -32.1  285  33 17   8.0   4.4
 24000 -32.4 -26.3  290  31 16   8.6   4.7 | -32.6 -26.7  285  33 17   8.4   4.6
 23000 -29.8 -21.6  290  30 15   8.5   4.7 | -30.0 -22.0  285  32 16   8.6   4.7
 22000 -27.2 -17.0  290  29 15   8.5   4.7 | -27.5 -17.5  285  31 16   8.6   4.7
 21000 -24.7 -12.5  290  27 14   7.7   4.2 | -24.9 -12.8  280  30 15   8.0   4.4
 20000 -22.4  -8.3  295  26 13   7.8   4.3 | -22.5  -8.5  285  27 14   8.1   4.4
 19500 -21.2  -6.2  295  26 13   7.8   4.3 | -21.3  -6.3  285  26 13   8.1   4.4
 19000 -20.1  -4.2  300  25 13   7.8   4.3 | -20.1  -4.2  285  24 13   8.1   4.4
 18500 -18.9  -2.0  300  24 13   7.9   4.3 | -18.9  -2.0  285  23 12   8.0   4.4
 18000 -17.7   0.1  305  24 12   7.9   4.3 | -17.7   0.1  285  21 11   8.0   4.4
 17500 -16.5   2.3  310  23 12   7.8   4.3 | -16.5   2.3  290  20 10   8.0   4.4
 17000 -15.4   4.3  310  23 12   7.6   4.2 | -15.3   4.5  290  19 10   8.0   4.4
 16500 -14.2   6.4  310  22 11   7.6   4.2 | -14.1   6.6  295  17  9   7.9   4.4
 16000 -13.2   8.2  315  21 11   6.8   3.7 | -13.0   8.6  300  16  8   7.2   4.0
 15500 -12.1  10.2  315  20 11   6.9   3.8 | -11.9  10.6  300  15  8   7.3   4.0
 15000 -11.1  12.0  315  20 10   6.4   3.5 | -10.9  12.4  300  14  7   6.9   3.8
 14500 -10.2  13.6  320  18 10   6.4   3.5 |  -9.8  14.4  305  13  7   6.9   3.8
 14000  -9.3  15.3  320  17  9   6.0   3.3 |  -8.8  16.2  305  12  6   6.7   3.7
 13500  -8.4  16.9  320  16  8   5.9   3.2 |  -7.8  18.0  300  11  6   6.6   3.6
 13000  -7.5  18.5  320  14  7   5.8   3.2 |  -6.9  19.6  300  11  5   6.3   3.5
 12500  -6.7  19.9  320  13  7   5.9   3.2 |  -6.0  21.2  295  10  5   6.2   3.4
 12000  -5.8  21.6  320  11  6   6.2   3.4 |  -5.1  22.8  290   9  5   6.3   3.5
 11500  -4.9  23.2  320  10  5   6.5   3.6 |  -4.1  24.6  280   8  4   6.5   3.6
 11000  -4.0  24.8  315   8  4   7.0   3.8 |  -3.2  26.2  270   7  4   7.1   3.9
 10500  -2.9  26.8  315   6  3   8.0   4.4 |  -2.1  28.2  265   6  3   8.1   4.4
 10250  -2.4  27.7  315   6  3   4.7   2.6 |  -1.6  29.1  260   6  3   5.3   2.9
 10000  -2.2  28.0  315   5  2   5.7   3.1 |  -1.3  29.7  255   6  3   6.3   3.5
  9750  -1.5  29.3  315   4  2   9.7   5.3 |  -0.6  30.9  250   5  3   9.8   5.4
  9500  -0.9  30.4  320   3  2   8.8   4.8 |   0.1  32.2  245   5  3   9.1   5.0
  9250  -0.2  31.6  330   2  1   8.5   4.7 |   0.7  33.3  245   5  3   8.5   4.6
  9000   0.4  32.7  335   2  1   7.6   4.2 |   1.3  34.3  235   5  2   7.8   4.3
  8750   0.9  33.6  360   1  1   8.0   4.4 |   1.9  35.4  235   4  2   8.8   4.8
  8500   1.5  34.7  040   1  1   8.6   4.7 |   2.6  36.7  230   4  2   9.7   5.3
  8250   2.6  36.7  080   2  1   6.2   3.4 |   3.7  38.7  220   3  2   6.1   3.3
  8000   3.1  37.6  085   2  1   7.7   4.2 |   4.3  39.7  215   3  2   9.9   5.4
  7750   3.7  38.7  095   3  2   8.3   4.6 |   5.1  41.2  210   3  2  11.6   6.4
  7500   4.3  39.7  100   4  2   6.4   3.5 |   5.9  42.6  210   3  1   8.7   4.8
  7250   4.7  40.5  100   4  2   4.9   2.7 |   6.4  43.5  205   3  1   6.7   3.7
  7000   5.1  41.2  100   4  2   7.3   4.0 |   7.0  44.6  205   3  1  11.7   6.4
  6750   5.7  42.3  110   4  2   6.7   3.7 |   8.1  46.6  205   3  1  12.9   7.1
  6500   6.0  42.8  110   4  2   4.0   2.2 |   8.8  47.8  200   2  1   9.7   5.3
  6250   6.3  43.3  110   4  2   4.0   2.2 |   9.6  49.3  200   2  1   9.3   5.1
  6000   6.6  43.9  105   4  2   5.4   3.0 |  10.3  50.5  195   2  1  11.9   6.5
  5750   7.1  44.8  110   3  1   8.7   4.8 |  11.5  52.7  200   2  1  21.6  11.9
  5500   7.5  45.5  105   2  1  -1.3  -0.7 |  13.4  56.1  190   2  1  25.7  14.1
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/22/2024 at 1500 MDT          |       03/22/2024 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +2.2        | CAPE...     0.0    LI...       +1.7
CINH...    -0.1    K Index...  +2.9        | CINH...    -0.1    K Index... +13.3
                                           |
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 -57.8 -72.0  275  57 30   1.2   0.6 | -57.9 -72.2  280  59 31   1.2   0.7
 45000 -56.1 -69.0  280  70 36   1.5   0.8 | -56.0 -68.8  280  71 37   1.6   0.9
 40000 -59.0 -74.2  275  65 33  -2.0  -1.1 | -58.8 -73.8  275  73 37  -1.9  -1.1
 38000 -59.3 -74.7  275  59 31   1.5   0.8 | -59.2 -74.6  275  68 35   1.1   0.6
 36000 -58.4 -73.1  275  51 26   1.5   0.8 | -58.5 -73.3  275  58 30   1.1   0.6
 34000 -57.1 -70.8  275  43 22   8.2   4.5 | -57.4 -71.3  270  49 25   9.1   5.0
 32000 -52.6 -62.7  280  41 21   7.5   4.1 | -52.4 -62.3  275  47 24   8.3   4.5
 30000 -48.0 -54.4  280  39 20   8.7   4.8 | -47.4 -53.3  275  45 23   8.6   4.7
 29000 -45.4 -49.7  280  37 19   8.7   4.8 | -44.8 -48.6  275  41 21   8.6   4.7
 28000 -42.8 -45.0  280  36 18   8.7   4.8 | -42.2 -44.0  275  37 19   8.6   4.7
 27000 -40.2 -40.4  280  34 18   8.4   4.6 | -39.7 -39.5  275  34 17   8.5   4.7
 26000 -37.8 -36.0  275  34 17   7.7   4.2 | -37.2 -35.0  270  33 17   8.1   4.4
 25000 -35.5 -31.9  275  34 17   7.7   4.2 | -34.8 -30.6  270  32 17   8.1   4.4
 24000 -32.6 -26.7  270  33 17   8.3   4.6 | -31.8 -25.2  265  32 16   7.9   4.4
 23000 -30.0 -22.0  270  31 16   8.6   4.7 | -29.4 -20.9  260  30 16   7.8   4.3
 22000 -27.5 -17.5  270  29 15   8.6   4.7 | -27.0 -16.6  255  29 15   7.8   4.3
 21000 -24.9 -12.8  270  27 14   8.0   4.4 | -24.7 -12.5  255  27 14   7.6   4.2
 20000 -22.5  -8.5  270  25 13   8.0   4.4 | -22.4  -8.3  250  25 13   7.6   4.2
 19500 -21.3  -6.3  270  24 12   8.0   4.4 | -21.3  -6.3  250  24 13   7.6   4.2
 19000 -20.1  -4.2  270  22 12   8.0   4.4 | -20.2  -4.4  245  24 12   7.7   4.2
 18500 -18.9  -2.0  270  21 11   7.9   4.3 | -19.1  -2.4  245  23 12   6.9   3.8
 18000 -17.7   0.1  270  20 10   7.8   4.3 | -18.0  -0.4  240  21 11   6.9   3.8
 17500 -16.6   2.1  265  19 10   7.7   4.2 | -17.0   1.4  240  20 10   7.0   3.8
 17000 -15.4   4.3  265  18  9   7.5   4.1 | -16.0   3.2  235  19 10   7.2   4.0
 16500 -14.3   6.3  265  17  9   7.5   4.1 | -14.9   5.2  230  18  9   7.2   4.0
 16000 -13.2   8.2  260  16  8   7.2   4.0 | -13.8   7.2  230  18  9   7.9   4.3
 15500 -12.2  10.0  260  15  7   7.3   4.0 | -12.7   9.1  230  17  9   7.8   4.3
 15000 -11.1  12.0  255  14  7   7.1   3.9 | -11.5  11.3  225  16  8   8.6   4.7
 14500 -10.0  14.0  250  13  7   7.1   3.9 | -10.2  13.6  225  15  8   8.7   4.8
 14000  -9.0  15.8  250  12  6   7.6   4.1 |  -8.9  16.0  225  14  7   9.0   4.9
 13500  -7.8  18.0  245  12  6   7.7   4.2 |  -7.6  18.3  225  13  7   9.1   5.0
 13000  -6.7  19.9  245  11  6   8.0   4.4 |  -6.2  20.8  225  13  6   9.1   5.0
 12500  -5.5  22.1  245  11  6   8.1   4.5 |  -4.9  23.2  225  12  6   9.1   5.0
 12000  -4.3  24.3  245  11  5   8.5   4.6 |  -3.5  25.7  225  11  6   9.0   5.0
 11500  -3.0  26.6  245  10  5   8.7   4.8 |  -2.2  28.0  230  10  5   8.9   4.9
 11000  -1.8  28.8  245  10  5   8.3   4.6 |  -0.8  30.6  230   9  5   8.2   4.5
 10500  -0.6  30.9  250   9  5   7.5   4.1 |   0.3  32.5  235   9  5   6.3   3.5
 10250   0.0  32.0  250   9  5   9.9   5.4 |   0.8  33.4  240   9  4  10.9   6.0
 10000   0.9  33.6  250   8  4  10.4   5.7 |   1.8  35.2  240   8  4  12.1   6.6
  9750   1.5  34.7  250   8  4   8.3   4.6 |   2.5  36.5  240   8  4   8.1   4.4
  9500   2.2  36.0  250   8  4   9.0   4.9 |   3.2  37.8  240   7  4   9.5   5.2
  9250   2.8  37.0  255   7  4   8.5   4.7 |   3.8  38.8  245   7  4   7.8   4.3
  9000   3.4  38.1  260   7  3   8.5   4.7 |   4.4  39.9  250   7  4   7.5   4.1
  8750   4.1  39.4  260   6  3   9.0   4.9 |   5.0  41.0  255   7  3   9.4   5.2
  8500   5.4  41.7  260   6  3   8.3   4.6 |   5.7  42.3  255   6  3  10.0   5.5
  8250   6.0  42.8  265   5  3   7.9   4.3 |   7.1  44.8  260   6  3   7.9   4.3
  8000   6.7  44.1  270   5  3  10.4   5.7 |   7.7  45.9  265   6  3   9.1   5.0
  7750   7.5  45.5  265   5  3  11.8   6.5 |   8.4  47.1  265   5  3  10.2   5.6
  7500   8.4  47.1  265   5  2   9.3   5.1 |   9.2  48.6  265   5  3   9.0   4.9
  7250   8.9  48.0  275   5  2   7.3   4.0 |   9.8  49.6  270   5  3   7.9   4.3
  7000   9.6  49.3  280   5  2  10.9   6.0 |  10.5  50.9  275   5  3  10.0   5.5
  6750  10.5  50.9  270   4  2  12.2   6.7 |  11.3  52.3  275   5  3  11.3   6.2
  6500  11.3  52.3  275   4  2  10.2   5.6 |  12.1  53.8  270   5  2  10.2   5.6
  6250  12.1  53.8  280   4  2   9.8   5.4 |  12.8  55.0  280   5  3  10.6   5.8
  6000  12.8  55.0  285   4  2  10.5   5.8 |  13.6  56.5  285   5  3   8.2   4.5
  5750  13.8  56.8  275   4  2  18.4  10.1 |  14.1  57.4  275   4  2   7.8   4.3
  5500  16.1  61.0  290   4  2  47.6  26.1 |  15.6  60.1  290   5  2  43.6  23.9
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     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) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CINH (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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