Soaring Guidance
Issued by NWS Grand Junction, CO

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548
UXUS97 KGJT 081306
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
606 AM MST Sunday, December 8, 2024

This forecast is for Sunday, December 8, 2024:

If the trigger temperature of 55.8 F/13.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 209 ft/min (1.1 m/s)
   Maximum height of thermals.................. 7314 ft MSL (2475 ft AGL)

Forecast maximum temperature................... 48.0 F/9.3 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6587 ft MSL (1747 ft AGL)
Thermal soaring outlook for Monday 12/09....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:21:29 / 16:51:17 MST
Total possible sunshine........... 9 hr 29 min 48 sec (569 min 48 sec)
Altitude of sun at 12:06:23 MST... 28.04 degrees

Upper air data from rawinsonde observation taken on 12/08/2024 at 0500 MST

Freezing level.................. 5176 ft MSL (337 ft AGL)
Additional freezing level....... 11793 ft MSL (6954 ft AGL)
Convective condensation level... 21207 ft MSL (16368 ft AGL)
Lifted condensation level....... 12675 ft MSL (7836 ft AGL)
Lifted index.................... +15.6
K index......................... -1.7

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  -61.9 -79.4   265   46   24  -5.9  -3.3   98.0 208.4    50.7      M    M
 45000  -60.1 -76.2   285   52   27  -7.0  -3.8   75.1 167.1    40.5      M    M
 40000  -64.4 -83.9   290   36   19   8.7   4.8   45.0 113.0    23.7      M    M
 38000  -59.0 -74.2   285   33   17   8.2   4.5   44.3 111.8    23.9      M    M
 36000  -54.3 -65.7   280   32   16   8.9   4.9   42.6 108.8    23.4      M    M
 34000  -48.7 -55.7   280   33   17   8.3   4.6   42.2 108.0    23.7      M    M
 32000  -44.0 -47.2   275   32   16   9.3   5.1   40.7 105.2    23.2      M    M
 30000  -38.0 -36.4   275   32   16   9.0   4.9   39.9 103.8    23.3      M    M
 29000  -35.3 -31.5   275   28   14   8.2   4.5   39.7 103.4    23.4      M    M
 28000  -33.1 -27.6   275   30   15   7.3   4.0   38.7 101.7    22.9      M    M
 27000  -30.8 -23.4   280   29   15   7.6   4.2   37.9 100.2    22.6      M    M
 26000  -29.0 -20.2   275   26   13   6.2   3.4   36.6  97.8    21.8      M    M
 25000  -27.0 -16.6   290   27   14   7.2   4.0   35.4  95.8    21.1      M    M
 24000  -25.6 -14.1   290   27   14   7.6   4.2   33.6  92.4    19.8      M    M
 23000  -23.1  -9.6   295   29   15   9.3   5.1   33.0  91.4    19.6      M    M
 22000  -20.5  -4.9   295   31   16   8.1   4.5   32.7  90.9    19.6      M    M
 21000  -18.0  -0.4   295   30   16   8.6   4.7   32.3  90.1    19.4      M    M
 20000  -15.4   4.3   295   29   15   8.2   4.5   31.8  89.3    19.2      M    M
 19500  -14.2   6.4   300   28   15   8.0   4.4   31.5  88.7    19.0      M    M
 19000  -13.1   8.4   300   27   14   8.0   4.4   31.2  88.2    18.9      M    M
 18500  -11.9  10.6   300   24   12   8.0   4.4   30.9  87.6    18.7      M    M
 18000  -10.8  12.6   295   22   11   7.1   3.9   30.5  87.0    18.5      M    M
 17500   -9.8  14.4   295   21   11   7.0   3.8   30.0  86.0    18.1      M    M
 17000   -8.6  16.5   295   22   11   7.5   4.1   29.6  85.3    17.9      M    M
 16500   -7.0  19.4   295   21   11   5.3   2.9   28.9  84.1    17.5      M    M
 16000   -6.3  20.7   300   20   10   4.8   2.6   28.1  82.6    16.8      M    M
 15500   -5.6  21.9   295   19   10   5.0   2.7   27.3  81.1    16.1      M    M
 15000   -4.9  23.2   295   21   11   4.8   2.7   26.5  79.7    15.4      M    M
 14500   -4.2  24.4   300   24   12   5.0   2.8   25.6  78.2    14.7      M    M
 14000   -3.5  25.7   300   25   13   5.2   2.8   24.9  76.8    14.1      M    M
 13500   -2.8  27.0   300   25   13   5.1   2.8   24.1  75.4    13.4      M    M
 13000   -2.2  28.0   305   23   12   2.4   1.3   23.2  73.7    12.6      M    M
 12500   -1.4  29.5   305   22   11   7.4   4.1   22.3  72.2    12.0      M    M
 12000   -0.3  31.5   305   18    9   7.3   4.0   22.0  71.5    11.7      M    M
 11500    0.7  33.3   280   13    7   6.5   3.5   21.5  70.7    11.3      M    M
 11000    1.7  35.1   250   12    6   7.5   4.1   21.0  69.7    10.9      M    M
 10500    2.4  36.3   250   12    6   1.0   0.5   20.2  68.3    10.3      M    M
 10250    2.4  36.3   250   15    8  -7.0  -3.8   19.3  66.7     9.5      M    M
 10000    1.7  35.1   250   16    8  -8.0  -4.4   17.7  63.9     8.1      M    M
  9750    1.4  34.5   260   14    7  -2.9  -1.6   16.6  61.9     7.1      M    M
  9500    1.1  34.0   260   15    8  -1.9  -1.0   15.6  60.1     6.1      M    M
  9250    1.1  34.0   250   11    6  -0.0  -0.0   14.8  58.7     5.4      M    M
  9000    1.1  34.0   225    8    4  -0.4  -0.2   14.0  57.2     4.7      M    M
  8750    1.1  34.0   220    7    4   1.3   0.7   13.3  55.9     4.0      M    M
  8500    1.2  34.2   225    7    4   3.1   1.7   12.7  54.8     3.4      M    M
  8250    1.4  34.5   225    7    3  -0.6  -0.3   12.1  53.8     2.8      M    M
  8000    1.2  34.2   210    7    4  -0.5  -0.3   11.2  52.1     1.9      M    M
  7750    1.4  34.5   195    8    4   4.4   2.4   10.6  51.1     1.4      M    M
  7500    1.6  34.9   175    9    5   0.4   0.2   10.1  50.2     0.8      M    M
  7250    1.4  34.5   165   11    6  -3.0  -1.6    9.2  48.6    -0.1    209  1.1
  7000    1.2  34.2   155   13    6  -1.7  -0.9    8.3  46.9    -1.0    207  1.1
  6750    1.0  33.8   155   13    7  -4.1  -2.3    7.4  45.2    -1.9    206  1.0
  6500    0.5  32.9   145   12    6  -9.8  -5.4    6.1  42.9    -3.1    213  1.1
  6250    0.0  32.0   140   12    6   0.4   0.2    4.8  40.6    -4.4    221  1.1
  6000    0.6  33.1   130   12    6   9.3   5.1    4.6  40.3    -4.6    197  1.0
  5750    1.1  34.0   135   11    5   8.4   4.6    4.5  40.0    -4.8    174  0.9
  5500    1.7  35.1   130   10    5   3.5   1.9    4.3  39.8    -5.0    150  0.8
  5250    1.2  34.2   140    9    4 -16.6  -9.1    3.1  37.7    -6.2    156  0.8
  5000   -0.7  30.7   150    8    4 -33.1 -18.1    0.4  32.8    -8.9    207  1.1

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

           12/08/2024 at 0800 MST          |       12/08/2024 at 1100 MST
                                           |
CAPE...     0.0    LI...       +6.4        | CAPE...     0.0    LI...       +6.4
CINH...    -0.1    K Index...  +5.3        | CINH...    -0.2    K Index...  +3.7
                                           |
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 -62.4 -80.3  260  44 22   1.9   1.1 | -62.2 -80.0  260  57 29   2.1   1.2
 45000 -59.7 -75.5  265  49 25  -1.2  -0.7 | -59.0 -74.2  260  57 29  -1.0  -0.6
 40000 -62.5 -80.5  270  49 25  -1.9  -1.1 | -62.0 -79.6  265  65 34  -2.0  -1.1
 38000 -60.1 -76.2  270  49 25   8.0   4.4 | -60.0 -76.0  265  66 34   7.4   4.1
 36000 -54.7 -66.5  265  48 25   8.0   4.4 | -55.6 -68.1  265  64 33   7.4   4.1
 34000 -49.8 -57.6  260  49 25   8.4   4.6 | -50.4 -58.7  265  62 32   8.1   4.5
 32000 -44.8 -48.6  265  50 26   8.4   4.6 | -45.5 -49.9  265  61 31   8.1   4.5
 30000 -39.8 -39.6  270  50 26   8.0   4.4 | -40.7 -41.3  270  58 30   7.9   4.3
 29000 -37.4 -35.3  270  49 25   8.0   4.4 | -38.4 -37.1  270  56 29   7.8   4.3
 28000 -35.1 -31.2  275  48 25   8.0   4.4 | -36.1 -33.0  270  54 28   7.8   4.3
 27000 -32.7 -26.9  275  47 24   7.0   3.8 | -33.8 -28.8  275  51 26   7.0   3.8
 26000 -30.7 -23.3  280  44 23   6.9   3.8 | -31.7 -25.1  275  48 25   6.8   3.7
 25000 -28.6 -19.5  280  42 22   6.9   3.8 | -29.7 -21.5  280  45 23   6.8   3.7
 24000 -26.6 -15.9  285  40 21   7.0   3.8 | -27.7 -17.9  280  42 21   7.1   3.9
 23000 -24.0 -11.2  285  38 19   7.0   3.9 | -25.4 -13.7  285  39 20   7.6   4.2
 22000 -21.9  -7.4  290  36 18   7.0   3.9 | -23.1  -9.6  285  37 19   7.6   4.2
 21000 -19.7  -3.5  295  34 18   7.9   4.3 | -20.2  -4.4  285  35 18   7.8   4.3
 20000 -17.4   0.7  295  33 17   7.8   4.3 | -17.9  -0.2  285  34 18   7.8   4.3
 19500 -16.3   2.7  295  33 17   7.8   4.3 | -16.7   1.9  285  34 18   7.8   4.3
 19000 -15.1   4.8  300  33 17   7.9   4.3 | -15.6   3.9  285  34 17   7.9   4.3
 18500 -14.0   6.8  300  33 17   7.2   4.0 | -14.5   5.9  285  34 17   6.9   3.8
 18000 -12.9   8.8  300  33 17   7.3   4.0 | -13.4   7.9  290  34 17   6.9   3.8
 17500 -11.8  10.8  300  33 17   7.2   3.9 | -12.4   9.7  290  34 17   6.7   3.7
 17000 -10.8  12.6  305  32 17   7.1   3.9 | -11.5  11.3  290  34 17   6.3   3.5
 16500  -9.8  14.4  305  32 16   7.1   3.9 | -10.6  12.9  290  33 17   6.4   3.5
 16000  -8.7  16.3  305  31 16   7.1   3.9 |  -9.7  14.5  290  33 17   5.7   3.1
 15500  -7.7  18.1  305  31 16   7.1   3.9 |  -8.9  16.0  290  33 17   5.8   3.2
 15000  -6.6  20.1  310  30 15   6.9   3.8 |  -8.1  17.4  290  32 16   5.6   3.1
 14500  -5.6  21.9  310  29 15   6.8   3.7 |  -7.3  18.9  290  31 16   5.5   3.0
 14000  -4.6  23.7  310  28 14   6.6   3.6 |  -6.5  20.3  290  30 16   5.4   3.0
 13500  -3.6  25.5  310  26 14   6.4   3.5 |  -5.8  21.6  290  29 15   5.3   2.9
 13000  -2.7  27.1  310  25 13   5.9   3.2 |  -5.0  23.0  295  27 14   5.3   2.9
 12500  -1.8  28.8  310  24 12   5.2   2.8 |  -4.2  24.4  295  26 13   5.2   2.9
 12000  -1.0  30.2  305  22 11   4.5   2.5 |  -3.4  25.9  295  25 13   5.1   2.8
 11500  -0.5  31.1  305  21 11   2.7   1.5 |  -2.7  27.1  295  23 12   4.8   2.6
 11000  -0.1  31.8  300  19 10   2.2   1.2 |  -1.9  28.6  295  22 11   4.2   2.3
 10500   0.1  32.2  300  17  9   0.9   0.5 |  -1.5  29.3  295  20 10   2.8   1.5
 10250   0.1  32.2  295  16  8   1.1   0.6 |  -1.2  29.8  295  20 10   2.8   1.5
 10000   0.2  32.4  295  15  8   0.7   0.4 |  -1.0  30.2  295  19 10   3.1   1.7
  9750   0.3  32.5  290  14  7   0.7   0.4 |  -0.8  30.6  290  17  9   2.4   1.3
  9500   0.3  32.5  285  13  7   1.0   0.6 |  -0.7  30.7  290  16  8   1.6   0.9
  9250   0.4  32.7  285  12  6   1.0   0.5 |  -0.5  31.1  290  14  7   1.8   1.0
  9000   0.4  32.7  280  11  6   0.8   0.4 |  -0.4  31.3  285  13  7   2.3   1.2
  8750   0.5  32.9  275  10  5   1.0   0.5 |  -0.2  31.6  280  12  6   2.5   1.3
  8500   0.6  33.1  270   9  5   1.4   0.8 |  -0.0  32.0  280  11  6   2.1   1.1
  8250   0.7  33.3  260   7  4   0.3   0.1 |   0.1  32.2  275  10  5   2.2   1.2
  8000   0.7  33.3  255   6  3   0.3   0.2 |   0.3  32.5  270   9  5   2.2   1.2
  7750   0.8  33.4  245   5  2   0.8   0.4 |   0.7  33.3  265   7  4   3.8   2.1
  7500   0.8  33.4  230   4  2   1.0   0.6 |   0.9  33.6  260   6  3   2.5   1.4
  7250   0.9  33.6  220   3  2   1.1   0.6 |   1.0  33.8  260   5  3   0.4   0.2
  7000   1.0  33.8  205   3  2   2.4   1.3 |   1.1  34.0  260   4  2   3.6   1.9
  6750   1.2  34.2  195   3  2   2.7   1.5 |   1.5  34.7  255   3  2   6.1   3.4
  6500   1.3  34.3  185   3  1   0.2   0.1 |   1.9  35.4  250   2  1   5.3   2.9
  6250   1.2  34.2  170   2  1  -1.8  -1.0 |   2.3  36.1  255   2  1   4.3   2.4
  6000   1.2  34.2  155   2  1   2.7   1.5 |   2.7  36.9  270   1  1   8.1   4.5
  5750   1.4  34.5  125   2  1  -1.9  -1.0 |   3.6  38.5  255   1  1  17.6   9.6
  5500  -1.3  29.7  090   1  1 -93.0 -51.1 |   4.6  40.3  275   1  0   0.9   0.5
  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

           12/08/2024 at 1400 MST          |       12/08/2024 at 1700 MST
                                           |
CAPE...     0.0    LI...       +6.9        | CAPE...     0.0    LI...       +6.8
CINH...     0.0    K Index...  -9.8        | CINH...    -0.3    K Index... -12.4
                                           |
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 -61.6 -78.9  265  65 33   2.1   1.2 | -61.0 -77.8  265  66 34   1.6   0.9
 45000 -58.4 -73.1  265  65 33   1.6   0.9 | -58.6 -73.5  265  68 35   1.5   0.8
 40000 -60.2 -76.4  265  71 37  -1.2  -0.7 | -59.9 -75.8  270  73 37  -1.0  -0.5
 38000 -58.7 -73.7  265  72 37   5.2   2.8 | -58.9 -74.0  270  73 38   4.4   2.4
 36000 -55.6 -68.1  265  71 37   5.2   2.8 | -56.2 -69.2  270  71 37   4.4   2.4
 34000 -52.1 -61.8  265  70 36   7.9   4.3 | -53.2 -63.8  270  70 36   8.2   4.5
 32000 -47.4 -53.3  270  66 34   7.9   4.3 | -48.4 -55.1  270  68 35   8.0   4.4
 30000 -42.8 -45.0  270  61 31   7.3   4.0 | -43.6 -46.5  270  66 34   7.6   4.2
 29000 -40.6 -41.1  270  58 30   7.4   4.0 | -41.3 -42.3  270  64 33   7.6   4.2
 28000 -38.3 -36.9  275  55 28   7.4   4.0 | -39.1 -38.4  270  62 32   7.6   4.2
 27000 -36.1 -33.0  275  52 27   7.6   4.2 | -36.8 -34.2  270  60 31   7.7   4.2
 26000 -33.7 -28.7  275  51 26   8.1   4.4 | -34.4 -29.9  270  61 31   7.9   4.3
 25000 -31.3 -24.3  275  51 26   8.1   4.4 | -32.1 -25.8  270  61 31   7.9   4.3
 24000 -28.3 -18.9  275  50 26   7.9   4.3 | -29.7 -21.5  270  61 32   7.9   4.4
 23000 -25.9 -14.6  275  49 25   7.8   4.3 | -26.9 -16.4  270  61 31   7.5   4.1
 22000 -23.6 -10.5  275  48 25   7.8   4.3 | -24.7 -12.5  270  60 31   7.5   4.1
 21000 -21.2  -6.2  275  47 24   7.9   4.4 | -22.4  -8.3  275  59 30   7.2   4.0
 20000 -18.8  -1.8  275  45 23   7.9   4.4 | -20.3  -4.5  275  56 29   7.2   3.9
 19500 -17.7   0.1  280  45 23   7.9   4.4 | -19.2  -2.6  275  54 28   7.2   3.9
 19000 -16.5   2.3  280  44 23   8.0   4.4 | -18.1  -0.6  275  53 27   7.2   3.9
 18500 -15.3   4.5  280  44 23   7.5   4.1 | -17.1   1.2  280  51 26   7.2   3.9
 18000 -14.2   6.4  280  43 22   7.4   4.1 | -16.0   3.2  280  49 25   7.2   3.9
 17500 -13.1   8.4  280  42 22   7.3   4.0 | -14.9   5.2  280  47 24   7.2   3.9
 17000 -12.1  10.2  280  41 21   6.4   3.5 | -13.8   7.2  280  45 23   6.9   3.8
 16500 -11.1  12.0  280  39 20   6.5   3.6 | -12.8   9.0  280  44 23   7.0   3.8
 16000 -10.2  13.6  280  38 20   5.3   2.9 | -11.8  10.8  280  42 22   6.3   3.5
 15500  -9.4  15.1  280  37 19   5.3   2.9 | -10.9  12.4  280  40 21   6.2   3.4
 15000  -8.6  16.5  280  35 18   4.8   2.6 |  -9.9  14.2  280  38 20   5.6   3.1
 14500  -8.0  17.6  285  34 17   4.5   2.5 |  -9.2  15.4  280  36 19   5.1   2.8
 14000  -7.3  18.9  285  32 17   4.5   2.5 |  -8.4  16.9  280  34 17   5.1   2.8
 13500  -6.7  19.9  285  31 16   4.4   2.4 |  -7.7  18.1  280  32 16   5.0   2.7
 13000  -6.0  21.2  285  29 15   4.5   2.5 |  -7.0  19.4  280  30 15   5.0   2.8
 12500  -5.4  22.3  285  27 14   4.5   2.5 |  -6.2  20.8  280  28 14   4.9   2.7
 12000  -4.8  23.4  285  25 13   4.6   2.5 |  -5.5  22.1  280  26 13   5.0   2.7
 11500  -4.1  24.6  285  23 12   5.4   3.0 |  -4.8  23.4  280  24 12   5.5   3.0
 11000  -3.3  26.1  285  21 11   5.2   2.9 |  -4.0  24.8  275  22 11   5.4   3.0
 10500  -2.7  27.1  280  19 10   4.2   2.3 |  -3.3  26.1  275  20 10   4.3   2.4
 10250  -2.3  27.9  280  18  9   4.0   2.2 |  -3.0  26.6  270  19 10   3.8   2.1
 10000  -2.0  28.4  280  17  9   5.1   2.8 |  -2.7  27.1  270  18  9   6.2   3.4
  9750  -1.6  29.1  275  15  8   5.0   2.7 |  -2.2  28.0  265  17  9   6.8   3.7
  9500  -1.3  29.7  270  14  7   3.8   2.1 |  -1.8  28.8  265  16  8   4.6   2.5
  9250  -1.0  30.2  270  13  7   4.1   2.3 |  -1.5  29.3  260  15  8   5.5   3.0
  9000  -0.7  30.7  265  12  6   4.0   2.2 |  -1.1  30.0  255  14  7   4.1   2.2
  8750  -0.4  31.3  260  12  6   3.7   2.1 |  -0.9  30.4  255  14  7   3.8   2.1
  8500   0.1  32.2  255  10  5   3.6   1.9 |  -0.5  31.1  250  13  7   4.9   2.7
  8250   0.3  32.5  255   9  5   2.1   1.1 |   0.2  32.4  250  11  5   4.5   2.5
  8000   0.5  32.9  255   9  4   3.5   1.9 |   0.5  32.9  250  10  5   4.8   2.6
  7750   0.9  33.6  255   7  4   5.7   3.1 |   0.9  33.6  250   9  5   5.1   2.8
  7500   1.2  34.2  250   6  3   4.8   2.6 |   1.2  34.2  250   8  4   5.0   2.8
  7250   1.5  34.7  255   5  3   3.2   1.7 |   1.6  34.9  255   7  3   5.0   2.7
  7000   1.8  35.2  265   4  2   6.4   3.5 |   2.0  35.6  260   6  3   5.1   2.8
  6750   2.5  36.5  265   3  2   9.8   5.4 |   2.3  36.1  260   5  2   5.4   3.0
  6500   3.1  37.6  265   3  2   9.1   5.0 |   2.8  37.0  265   4  2   7.0   3.8
  6250   3.9  39.0  275   3  1  10.0   5.5 |   3.4  38.1  275   3  2   8.4   4.6
  6000   4.6  40.3  285   3  1   8.1   4.5 |   4.0  39.2  290   3  2   7.1   3.9
  5750   5.1  41.2  270   3  1   8.8   4.8 |   4.2  39.6  280   2  1  -2.9  -1.6
  5500   6.6  43.9  290   2  1  39.6  21.7 |   2.8  37.0  320   2  1 -42.9 -23.6
  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