Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211222
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0522 MST Sunday, December 21, 2014

This forecast is for Sunday, December 21, 2014:

If the trigger temperature of 47.0 F/8.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7649 ft MSL (2810 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 0600 MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5158 ft MSL (319 ft AGL)
Thermal soaring outlook for Monday 12/22....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:29:43 / 16:55:02 MST
Total possible sunshine........... 9 hr 25 min 20 sec (565 min 20 sec)
Altitude of sun at 12:12:22 MST... 27.51 degrees

Upper air data from rawinsonde observation taken on 12/21/2014 at 0500 MST

Freezing level.................. 5622 ft MSL (783 ft AGL)
Convective condensation level... 9963 ft MSL (5124 ft AGL)
Lifted condensation level....... 8150 ft MSL (3311 ft AGL)
Lifted index.................... +13.1
K index......................... +7.9

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  -61.2 -78.2   315   46   24   5.3   2.9  100.6 213.1    54.5      M    M
 45000  -56.4 -69.5   330   51   26   5.1   2.8   83.6 182.5    48.1      M    M
 40000  -59.4 -74.9   325   60   31  -4.0  -2.2   55.7 132.2    33.3      M    M
 38000  -57.3 -71.1   335   57   29   5.7   3.1   49.9 121.9    30.4      M    M
 36000  -55.5 -67.9   340   82   42   1.3   0.7   43.8 110.9    27.0      M    M
 34000  -56.5 -69.7   340  109   56   8.2   4.5   32.9  91.2    20.2      M    M
 32000  -51.2 -60.2   335  107   55   9.3   5.1   32.0  89.7    20.1      M    M
 30000  -45.5 -49.9   335  106   55   9.9   5.4   31.9  89.5    20.5      M    M
 29000  -42.7 -44.9   340  105   54   8.6   4.7   31.8  89.2    20.7      M    M
 28000  -40.1 -40.2   340   99   51   8.6   4.7   31.4  88.5    20.6      M    M
 27000  -37.6 -35.7   340   93   48   8.5   4.6   30.9  87.6    20.4      M    M
 26000  -34.9 -30.8   335   88   45   9.2   5.1   30.5  87.0    20.4      M    M
 25000  -32.2 -26.0   335   82   42   8.2   4.5   30.3  86.6    20.5      M    M
 24000  -29.8 -21.6   335   75   38   8.3   4.5   29.7  85.4    20.2      M    M
 23000  -27.1 -16.8   335   67   35   9.1   5.0   29.4  84.9    20.2      M    M
 22000  -24.5 -12.1   330   61   31   8.0   4.4   29.0  84.3    20.1      M    M
 21000  -22.1  -7.8   325   58   30   6.4   3.5   28.4  83.2    19.8      M    M
 20000  -20.4  -4.7   320   56   29   6.8   3.7   27.1  80.7    18.9      M    M
 19500  -19.3  -2.7   320   55   28   6.8   3.7   26.5  79.8    18.5      M    M
 19000  -17.8  -0.0   315   52   27   6.9   3.8   25.8  78.4    18.0      M    M
 18500  -16.7   1.9   310   51   26   9.0   4.9   25.4  77.8    17.8      M    M
 18000  -15.3   4.5   310   50   26   9.2   5.0   25.3  77.6    17.9      M    M
 17500  -13.9   7.0   310   49   25   9.0   4.9   25.2  77.4    17.8      M    M
 17000  -12.6   9.3   305   48   25   9.0   4.9   25.1  77.1    17.8      M    M
 16500  -11.2  11.8   305   48   25   9.0   4.9   25.0  76.9    17.8      M    M
 16000  -10.9  12.4   305   47   24   0.4   0.2   23.7  74.7    16.8      M    M
 15500  -10.0  14.0   305   45   23   6.8   3.7   23.0  73.5    16.3      M    M
 15000   -9.0  15.8   305   44   23   7.5   4.1   22.5  72.6    15.9      M    M
 14500   -8.7  16.3   305   42   22  -6.5  -3.6   21.4  70.5    14.9      M    M
 14000   -9.9  14.2   305   41   21  -5.2  -2.8   18.5  65.2    12.3      M    M
 13500  -10.2  13.6   300   37   19   1.8   1.0   16.6  61.8    10.6      M    M
 13000   -9.8  14.4   295   33   17  -2.2  -1.2   15.4  59.7     9.6      M    M
 12500  -10.2  13.6   290   30   16   3.4   1.9   13.3  55.9     7.7      M    M
 12000   -9.5  14.9   280   28   14   4.9   2.7   12.5  54.6     7.0      M    M
 11500   -8.8  16.2   270   23   12   5.0   2.7   11.7  53.1     6.3      M    M
 11000   -8.0  17.6   255   19   10   5.0   2.7   11.0  51.7     5.6      M    M
 10500   -7.3  18.9   235   18    9   4.8   2.7   10.2  50.4     4.9      M    M
 10250   -6.9  19.6   220   18    9   5.7   3.1    9.9  49.7     4.6      M    M
 10000   -6.4  20.5   210   19   10   7.6   4.1    9.6  49.3     4.4      M    M
  9750   -5.8  21.6   210   19   10   7.9   4.3    9.5  49.1     4.3      M    M
  9500   -5.3  22.5   210   18    9   7.6   4.2    9.3  48.8     4.1      M    M
  9250   -4.7  23.5   210   18    9   7.8   4.3    9.2  48.5     4.0      M    M
  9000   -4.1  24.6   210   17    9   7.1   3.9    9.0  48.2     3.8      M    M
  8750   -3.6  25.5   200   17    9   9.8   5.4    8.8  47.9     3.7      M    M
  8500   -3.0  26.6   190   18    9  -0.2  -0.1    8.7  47.6     3.5      M    M
  8250   -3.5  25.7   185   18   10  -6.6  -3.6    7.4  45.3     2.3      M    M
  8000   -3.6  25.5   175   20   10   1.3   0.7    6.5  43.7     1.5      M    M
  7750   -3.6  25.5   175   18    9  -4.6  -2.6    5.7  42.3     0.7      M    M
  7500   -4.1  24.6   175   16    8  -0.0  -0.0    4.5  40.2    -0.5    238  1.2
  7250   -3.6  25.5   180   14    7   8.8   4.8    4.3  39.7    -0.7    216  1.1
  7000   -3.0  26.6   180   12    6   7.1   3.9    4.1  39.4    -0.9    192  1.0
  6750   -2.5  27.5   185    9    5   7.5   4.1    3.9  39.1    -1.1    168  0.9
  6500   -1.9  28.6   195    7    4   7.5   4.1    3.8  38.8    -1.3    145  0.7
  6250   -1.4  29.5   210    5    3   7.4   4.1    3.6  38.5    -1.5    121  0.6
  6000   -0.9  30.4   245    4    2   7.7   4.2    3.4  38.2    -1.7     97  0.5
  5750   -0.3  31.5   260    4    2   6.5   3.6    3.3  37.9    -1.8     73  0.4
  5500    0.1  32.2   265    3    2   4.2   2.3    2.9  37.2    -2.2     55  0.3
  5250    0.3  32.5   275    3    1   3.6   2.0    2.5  36.4    -2.7     39  0.2
  5000    0.6  33.1   290    2    1   4.3   2.3    2.0  35.6    -3.1     23  0.1

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

           12/21/2014 at 0800 MST          |       12/21/2014 at 1100 MST
                                           |
K index... +16.4  LI... +3.9               | K index... +18.2  LI... +3.3
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... M
                                           |
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  330  43 22  -0.2  -0.1 | -60.2 -76.4  340  32 16  -1.6  -0.9
 45000 -59.5 -75.1  325  65 33  -0.2  -0.1 | -62.6 -80.7  335  46 24  -1.5  -0.8
 40000 -59.2 -74.6  340  66 34   0.2   0.1 | -59.9 -75.8  345  90 46   1.9   1.1
 38000 -58.1 -72.6  345  74 38   4.1   2.2 | -58.1 -72.6  345  99 51   4.3   2.3
 36000 -55.7 -68.3  345  91 47   4.0   2.2 | -55.5 -67.9  340  96 50   4.2   2.3
 34000 -53.2 -63.8  345 107 55   5.5   3.0 | -52.9 -63.2  335  94 48   5.7   3.2
 32000 -49.2 -56.6  340 107 55   5.9   3.2 | -48.9 -56.0  340  92 48   5.9   3.2
 30000 -45.4 -49.7  335 105 54   8.2   4.5 | -45.0 -49.0  345  88 45   8.6   4.7
 29000 -42.9 -45.2  340  98 50   8.2   4.5 | -42.4 -44.3  340  81 41   8.6   4.7
 28000 -40.5 -40.9  340  90 47   8.2   4.5 | -39.9 -39.8  335  73 38   8.7   4.7
 27000 -38.1 -36.6  340  83 43   8.4   4.6 | -37.3 -35.1  330  67 34   8.9   4.9
 26000 -35.4 -31.7  335  76 39   8.9   4.9 | -34.5 -30.1  325  67 34   9.2   5.0
 25000 -32.8 -27.0  335  68 35   8.9   4.9 | -31.8 -25.2  325  67 35   9.2   5.1
 24000 -30.1 -22.2  330  61 31   8.8   4.9 | -29.0 -20.2  320  68 35   9.0   4.9
 23000 -27.7 -17.9  325  57 30   8.0   4.4 | -26.8 -16.2  325  67 34   7.3   4.0
 22000 -25.3 -13.5  325  55 28   8.0   4.4 | -24.6 -12.3  325  65 34   7.3   4.0
 21000 -23.0  -9.4  320  52 27   7.6   4.2 | -22.4  -8.3  325  64 33   7.3   4.0
 20000 -20.9  -5.6  320  53 27   7.0   3.8 | -20.3  -4.5  325  58 30   7.2   4.0
 19500 -19.8  -3.6  325  53 27   7.0   3.9 | -19.2  -2.6  320  55 28   7.2   4.0
 19000 -18.8  -1.8  325  53 28   7.0   3.9 | -18.1  -0.6  320  52 27   7.2   4.0
 18500 -17.8  -0.0  325  54 28   7.1   3.9 | -17.1   1.2  320  49 25   7.0   3.9
 18000 -16.7   1.9  325  52 27   7.4   4.0 | -16.1   3.0  320  46 24   6.5   3.6
 17500 -15.6   3.9  325  50 26   7.4   4.1 | -15.2   4.6  315  44 22   6.4   3.5
 17000 -14.6   5.7  325  48 25   6.5   3.6 | -14.2   6.4  315  42 22   7.2   3.9
 16500 -13.6   7.5  325  47 24   6.5   3.6 | -13.1   8.4  320  42 21   7.2   4.0
 16000 -12.7   9.1  325  46 23   6.3   3.5 | -12.1  10.2  320  42 21   7.2   4.0
 15500 -11.8  10.8  325  45 23   6.1   3.4 | -10.5  13.1  325  44 23   7.3   4.0
 15000 -10.4  13.3  325  44 23   6.2   3.4 |  -9.5  14.9  330  46 23   6.0   3.3
 14500  -9.5  14.9  325  44 23   6.2   3.4 |  -8.6  16.5  330  45 23   5.7   3.2
 14000  -8.6  16.5  325  45 23   4.7   2.6 |  -7.8  18.0  335  45 23   5.2   2.9
 13500  -8.1  17.4  320  43 22   3.4   1.9 |  -7.1  19.2  330  43 22   4.8   2.6
 13000  -7.6  18.3  315  42 22   3.4   1.9 |  -6.4  20.5  330  41 21   4.3   2.3
 12500  -7.1  19.2  315  40 20   3.6   2.0 |  -5.8  21.6  325  39 20   3.5   1.9
 12000  -6.6  20.1  315  37 19   3.7   2.0 |  -5.3  22.5  320  37 19   3.2   1.7
 11500  -6.1  21.0  310  35 18   3.6   2.0 |  -4.9  23.2  315  36 18   2.6   1.4
 11000  -5.5  22.1  305  32 16   2.6   1.4 |  -4.6  23.7  310  35 18   2.2   1.2
 10500  -5.4  22.3  300  27 14   0.6   0.3 |  -4.3  24.3  305  31 16   1.6   0.9
 10250  -5.3  22.5  295  25 13   1.2   0.7 |  -4.2  24.4  300  30 15   1.9   1.1
 10000  -5.2  22.6  295  23 12   2.8   1.5 |  -4.1  24.6  295  28 14   1.3   0.7
  9750  -4.9  23.2  290  22 11   3.3   1.8 |  -4.0  24.8  290  25 13   0.6   0.3
  9500  -4.7  23.5  285  21 11   3.1   1.7 |  -3.9  25.0  285  23 12   0.7   0.4
  9250  -4.5  23.9  275  20 10   3.3   1.8 |  -3.9  25.0  280  21 11   0.8   0.4
  9000  -4.2  24.4  270  19 10   5.6   3.1 |  -3.7  25.3  275  20 10   4.0   2.2
  8750  -3.6  25.5  265  20 10   7.8   4.3 |  -3.3  26.1  270  20 10   7.0   3.8
  8500  -3.1  26.4  265  20 10   7.7   4.2 |  -2.8  27.0  265  19 10   6.5   3.6
  8250  -2.5  27.5  260  20 10   7.8   4.3 |  -2.3  27.9  265  19 10   7.8   4.3
  8000  -1.9  28.6  255  19 10   7.5   4.1 |  -1.6  29.1  260  19 10   8.8   4.8
  7750  -1.4  29.5  255  18  9   6.3   3.5 |  -1.0  30.2  260  19 10   7.6   4.2
  7500  -1.0  30.2  250  17  9   5.6   3.1 |  -0.5  31.1  255  18  9   6.8   3.7
  7250  -0.6  30.9  250  15  8   4.8   2.6 |  -0.0  32.0  255  17  9   5.1   2.8
  7000  -0.3  31.5  245  13  7   4.0   2.2 |   0.3  32.5  250  14  7   3.9   2.1
  6750   0.0  32.0  235  11  6   4.4   2.4 |   0.5  32.9  240  11  6   1.7   1.0
  6500   0.3  32.5  225  10  5   2.7   1.5 |   0.7  33.3  230   9  4   4.2   2.3
  6250   0.4  32.7  215   9  4   1.0   0.6 |   1.2  34.2  225   7  4   8.4   4.6
  6000   0.5  32.9  200   8  4   1.4   0.8 |   1.8  35.2  220   6  3   7.8   4.3
  5750   0.6  33.1  185   7  4   0.6   0.4 |   2.3  36.1  220   5  3   7.6   4.1
  5500   0.6  33.1  175   6  3  -0.5  -0.3 |   2.8  37.0  220   5  2   6.9   3.8
  5250   0.5  32.9  175   5  3  -0.6  -0.3 |   3.3  37.9  225   5  2   7.0   3.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/21/2014 at 1400 MST          |       12/21/2014 at 1700 MST
                                           |
K index... +20.0  LI... +3.1               | K index... +19.0  LI... +3.0
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -59.1 -74.4  345  32 16   0.7   0.4 | -59.9 -75.8  345  25 13   1.1   0.6
 45000 -58.0 -72.4  335  46 24   0.8   0.4 | -58.3 -72.9  340  34 18   1.1   0.6
 40000 -57.2 -71.0  350  91 47   0.5   0.3 | -57.7 -71.9  340  81 42   0.4   0.2
 38000 -56.6 -69.9  350  99 51   1.8   1.0 | -56.7 -70.1  340  93 48   3.1   1.7
 36000 -55.5 -67.9  345  95 49   1.8   1.0 | -54.8 -66.6  340  99 51   3.1   1.7
 34000 -54.1 -65.4  345  91 47   7.1   3.9 | -52.7 -62.9  340 103 53   6.2   3.4
 32000 -50.1 -58.2  345  86 44   6.8   3.7 | -49.1 -56.4  335  89 46   5.9   3.2
 30000 -45.8 -50.4  340  79 41   9.4   5.2 | -45.4 -49.7  335  77 40   9.4   5.1
 29000 -43.1 -45.6  335  74 38   9.2   5.0 | -42.7 -44.9  335  78 40   9.0   4.9
 28000 -39.7 -39.5  330  68 35   9.2   5.0 | -39.3 -38.7  330  80 41   9.0   5.0
 27000 -36.9 -34.4  325  64 33   8.9   4.9 | -36.6 -33.9  330  81 42   8.8   4.8
 26000 -34.4 -29.9  325  63 33   8.7   4.8 | -34.0 -29.2  330  83 43   8.7   4.8
 25000 -31.8 -25.2  325  63 33   8.7   4.8 | -31.4 -24.5  330  85 44   8.7   4.8
 24000 -29.2 -20.6  325  63 32   8.4   4.6 | -28.9 -20.0  330  86 44   8.4   4.6
 23000 -26.9 -16.4  325  65 34   7.6   4.2 | -26.6 -15.9  325  80 41   7.4   4.1
 22000 -24.6 -12.3  320  68 35   7.6   4.2 | -24.4 -11.9  320  73 37   7.5   4.1
 21000 -22.4  -8.3  320  70 36   8.0   4.4 | -22.2  -8.0  315  66 34   7.5   4.1
 20000 -19.9  -3.8  310  64 33   8.3   4.5 | -20.0  -4.0  310  60 31   7.5   4.1
 19500 -18.7  -1.7  310  61 32   8.3   4.5 | -18.9  -2.0  305  57 29   7.6   4.1
 19000 -17.5   0.5  305  59 30   8.3   4.5 | -17.8  -0.0  300  54 28   7.5   4.1
 18500 -16.3   2.7  300  57 29   7.8   4.3 | -16.6   2.1  300  51 26   7.3   4.0
 18000 -15.3   4.5  300  56 29   7.0   3.8 | -15.7   3.7  300  51 26   6.6   3.6
 17500 -14.2   6.4  300  54 28   7.1   3.9 | -14.7   5.5  305  52 27   6.6   3.6
 17000 -13.3   8.1  300  53 27   5.5   3.0 | -13.7   7.3  310  54 28   6.6   3.6
 16500 -12.5   9.5  305  52 27   5.6   3.1 | -12.8   9.0  315  57 29   6.6   3.6
 16000 -11.7  10.9  310  52 27   5.6   3.1 | -11.8  10.8  320  61 31   6.8   3.7
 15500 -10.8  12.6  315  55 28   5.6   3.1 | -10.8  12.6  320  64 33   6.9   3.8
 15000 -10.0  14.0  320  58 30   5.7   3.1 |  -9.7  14.5  320  67 34   6.9   3.8
 14500  -9.1  15.6  320  59 31   6.1   3.3 |  -8.7  16.3  320  68 35   6.6   3.6
 14000  -8.3  17.1  325  60 31   6.1   3.3 |  -7.8  18.0  320  69 35   6.8   3.8
 13500  -6.9  19.6  330  59 31   6.1   3.3 |  -6.7  19.9  320  67 34   4.4   2.4
 13000  -6.0  21.2  330  58 30   5.7   3.1 |  -6.1  21.0  320  65 33   3.8   2.1
 12500  -5.3  22.5  330  52 27   5.2   2.8 |  -5.6  21.9  320  59 30   2.9   1.6
 12000  -4.5  23.9  330  45 23   4.7   2.6 |  -5.2  22.6  315  52 27   3.3   1.8
 11500  -4.0  24.8  325  41 21   3.8   2.1 |  -4.7  23.5  310  46 24   4.3   2.4
 11000  -3.4  25.9  320  37 19   3.1   1.7 |  -4.0  24.8  305  41 21   3.9   2.2
 10500  -3.1  26.4  315  33 17   2.0   1.1 |  -3.6  25.5  300  35 18   3.2   1.8
 10250  -3.0  26.6  310  32 16   2.1   1.2 |  -3.3  26.1  295  32 16   2.9   1.6
 10000  -2.9  26.8  305  31 16   0.4   0.2 |  -3.1  26.4  290  29 15   2.7   1.5
  9750  -2.9  26.8  300  28 14  -1.0  -0.6 |  -2.9  26.8  290  27 14   3.1   1.7
  9500  -3.0  26.6  295  25 13  -0.7  -0.4 |  -2.7  27.1  285  25 13   3.1   1.7
  9250  -3.0  26.6  290  23 12  -0.5  -0.3 |  -2.5  27.5  275  24 12   2.9   1.6
  9000  -3.0  26.6  285  21 11   3.0   1.6 |  -2.2  28.0  270  23 12   5.8   3.2
  8750  -2.6  27.3  280  19 10   5.4   3.0 |  -1.6  29.1  270  23 12   8.2   4.5
  8500  -2.2  28.0  275  18  9   4.2   2.3 |  -1.1  30.0  265  22 12   7.4   4.0
  8250  -1.9  28.6  270  17  9   6.7   3.7 |  -0.5  31.1  265  22 11   8.4   4.6
  8000  -1.2  29.8  265  16  8   9.7   5.3 |   0.2  32.4  260  22 11   9.4   5.2
  7750  -0.6  30.9  265  15  8   8.8   4.8 |   0.9  33.6  260  22 11   8.8   4.8
  7500   0.1  32.2  260  14  7   8.3   4.5 |   1.5  34.7  255  21 11   8.5   4.7
  7250   0.7  33.3  260  13  7   8.9   4.9 |   2.1  35.8  255  20 10   8.3   4.6
  7000   1.4  34.5  260  12  6   9.3   5.1 |   2.7  36.9  250  18  9   7.7   4.2
  6750   2.1  35.8  260  11  6   9.1   5.0 |   3.2  37.8  250  16  8   6.8   3.7
  6500   2.8  37.0  260  10  5   9.5   5.2 |   3.7  38.7  250  14  7   6.1   3.4
  6250   3.5  38.3  260   9  5  10.1   5.6 |   4.2  39.6  245  12  6   5.9   3.2
  6000   4.2  39.6  260   9  4  10.0   5.5 |   4.6  40.3  245  10  5   5.7   3.1
  5750   5.0  41.0  260   8  4   8.9   4.9 |   5.0  41.0  240   7  4   4.4   2.4
  5500   5.5  41.9  260   7  4   7.7   4.2 |   5.1  41.2  235   4  2   0.8   0.5
  5250   6.1  43.0  260   7  4   7.7   4.2 |   5.1  41.2  235   4  2  -2.4  -1.3
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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