Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221226
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0526 MST Monday, December 22, 2014

This forecast is for Monday, December 22, 2014:

If the trigger temperature of 50.4 F/10.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5589 ft MSL (750 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1430 MST
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................. None
Thermal soaring outlook for Tuesday 12/23...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:30:11 / 16:55:33 MST
Total possible sunshine........... 9 hr 25 min 22 sec (565 min 22 sec)
Altitude of sun at 12:12:52 MST... 27.52 degrees

Upper air data from rawinsonde observation taken on 12/22/2014 at 0500 MST

Freezing level.................. 8172 ft MSL (3333 ft AGL)
Convective condensation level... 9985 ft MSL (5146 ft AGL)
Lifted condensation level....... 7298 ft MSL (2459 ft AGL)
Lifted index.................... +11.4
K index......................... +16.2

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  -56.8 -70.2   340   62   32   5.0   2.7  107.8 226.0    59.0      M    M
 45000  -53.0 -63.4   340   57   29   7.1   3.9   88.0 190.4    51.3      M    M
 40000  -53.1 -63.6   330   86   44   5.7   3.1   64.6 148.3    39.6      M    M
 38000  -55.2 -67.4   335  122   63  -7.3  -4.0   52.5 126.6    32.6      M    M
 36000  -53.5 -64.3   340  146   75   6.4   3.5   46.3 115.4    29.2      M    M
 34000  -49.9 -57.8   335  156   80   6.3   3.4   43.2 109.8    27.8      M    M
 32000  -46.5 -51.7   330  131   67  -4.9  -2.7   38.9 101.9    25.4      M    M
 30000  -46.2 -51.2   325  104   54  -9.1  -5.0   31.4  88.5    20.5      M    M
 29000  -44.5 -48.1   325  105   54   9.7   5.3   29.7  85.4    19.4      M    M
 28000  -41.7 -43.1   325  105   54   8.9   4.9   29.5  85.1    19.6      M    M
 27000  -39.1 -38.4   330  106   54   8.9   4.9   29.1  84.4    19.5      M    M
 26000  -36.4 -33.5   330  106   55   9.1   5.0   28.9  84.0    19.6      M    M
 25000  -33.6 -28.5   330  107   55   9.1   5.0   28.7  83.7    19.7      M    M
 24000  -31.0 -23.8   325  100   52   8.5   4.7   28.3  82.9    19.6      M    M
 23000  -28.5 -19.3   320   93   48   6.0   3.3   27.9  82.3    19.4      M    M
 22000  -27.3 -17.1   315   86   44   5.4   3.0   25.8  78.5    17.9      M    M
 21000  -24.7 -12.5   310   80   41   8.6   4.7   25.4  77.8    17.8      M    M
 20000  -23.5 -10.3   320   80   41  -0.6  -0.3   23.4  74.1    16.3      M    M
 19500  -23.1  -9.6   320   79   41   7.0   3.8   22.2  71.9    15.3      M    M
 19000  -22.1  -7.8   325   78   40   6.3   3.4   21.5  70.8    14.9      M    M
 18500  -21.2  -6.2   325   77   39   5.9   3.2   20.9  69.7    14.4      M    M
 18000  -20.1  -4.2   325   76   39   9.5   5.2   20.6  69.0    14.2      M    M
 17500  -18.0  -0.4   325   75   39   9.2   5.1   20.4  68.7    14.1      M    M
 17000  -16.6   2.1   325   75   38   9.2   5.0   20.3  68.6    14.1      M    M
 16500  -15.3   4.5   325   74   38   8.1   4.4   20.3  68.5    14.2      M    M
 16000  -14.6   5.7   325   73   37   4.1   2.3   19.5  67.0    13.5      M    M
 15500  -13.8   7.2   325   65   34   5.1   2.8   18.6  65.6    12.8      M    M
 15000  -13.1   8.4   325   58   30   7.4   4.1   17.9  64.2    12.2      M    M
 14500  -11.7  10.9   320   51   26   9.4   5.2   17.9  64.2    12.2      M    M
 14000  -11.0  12.2   320   45   23   3.3   1.8   17.0  62.6    11.5      M    M
 13500  -10.0  14.0   320   42   22   6.0   3.3   16.5  61.6    11.1      M    M
 13000  -10.1  13.8   315   40   21  -1.5  -0.8   14.8  58.7     9.6      M    M
 12500   -9.7  14.5   315   38   20   2.7   1.5   13.7  56.7     8.6      M    M
 12000   -9.2  15.4   310   36   19   5.4   3.0   12.7  54.8     7.7      M    M
 11500   -8.2  17.2   310   36   18   6.7   3.7   12.2  53.9     7.3      M    M
 11000   -7.2  19.0   310   35   18   6.8   3.8   11.7  53.1     6.8      M    M
 10500   -6.1  21.0   315   35   18   8.2   4.5   11.3  52.4     6.5      M    M
 10250   -5.5  22.1   315   35   18   9.1   5.0   11.3  52.3     6.4      M    M
 10000   -4.8  23.4   315   35   18   8.8   4.8   11.2  52.1     6.4      M    M
  9750   -4.2  24.4   315   34   17   8.8   4.8   11.1  52.0     6.3      M    M
  9500   -3.5  25.7   315   32   16   8.7   4.8   11.0  51.9     6.3      M    M
  9250   -2.9  26.8   315   30   15   8.8   4.8   11.0  51.7     6.2      M    M
  9000   -2.2  28.0   315   28   14   8.8   4.8   10.9  51.6     6.1      M    M
  8750   -1.6  29.1   315   27   14   8.7   4.8   10.8  51.4     6.1      M    M
  8500   -0.9  30.4   315   26   13   8.8   4.8   10.7  51.3     6.0      M    M
  8250   -0.3  31.5   315   24   13   8.7   4.8   10.6  51.1     5.9      M    M
  8000    0.4  32.7   315   23   12   8.9   4.9   10.6  51.0     5.8      M    M
  7750    1.0  33.8   315   23   12   9.1   5.0   10.5  50.9     5.8      M    M
  7500    1.7  35.1   315   23   12   9.1   5.0   10.4  50.8     5.7      M    M
  7250    2.3  36.1   310   22   11   8.8   4.9   10.4  50.7     5.7      M    M
  7000    3.0  37.4   310   22   11  10.0   5.5   10.3  50.6     5.6      M    M
  6750    3.7  38.7   310   20   11   5.8   3.2   10.3  50.5     5.6      M    M
  6500    3.5  38.3   315   18    9 -10.6  -5.8    9.4  49.0     4.7      M    M
  6250    2.5  36.5   315   16    8  -5.4  -2.9    7.7  45.9     3.0      M    M
  6000    2.8  37.0   320   15    7   7.7   4.2    7.3  45.2     2.6      M    M
  5750    2.8  37.0   325   12    6 -11.6  -6.3    6.6  43.9     1.9      M    M
  5500    1.6  34.9   330    9    4 -10.9  -6.0    4.6  40.3    -0.1     67  0.3
  5250    1.6  34.9   345    6    3   4.9   2.7    3.8  38.9    -0.8     59  0.3
  5000    1.6  34.9   015    4    2  -9.1  -5.0    3.1  37.6    -1.6     52  0.3

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

           12/22/2014 at 0800 MST          |       12/22/2014 at 1100 MST
                                           |
K index... +14.2  LI... +4.1               | K index... +11.9  LI... +4.5
CAPE... 0.0  CIN... 0.0                    | 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 -56.1 -69.0  315  62 32   0.4   0.2 | -55.5 -67.9  315  51 26  -0.1  -0.0
 45000 -55.5 -67.9  325  82 42   0.6   0.3 | -55.6 -68.1  335  82 42   0.4   0.2
 40000 -53.7 -64.7  340 114 59   1.2   0.7 | -53.3 -63.9  340 108 56   1.6   0.9
 38000 -52.5 -62.5  340 127 65   3.3   1.8 | -51.9 -61.4  340 119 61   3.7   2.0
 36000 -50.5 -58.9  340 137 71   3.3   1.8 | -49.7 -57.5  345 132 68   3.7   2.0
 34000 -48.5 -55.3  340 148 76   3.1   1.7 | -47.4 -53.3  345 144 74   3.5   1.9
 32000 -47.0 -52.6  340 137 70   2.6   1.4 | -45.6 -50.1  340 138 71   3.1   1.7
 30000 -45.0 -49.0  340 123 63   6.9   3.8 | -43.4 -46.1  340 131 67   5.2   2.9
 29000 -42.9 -45.2  335 115 59   7.3   4.0 | -41.7 -43.1  335 125 65   5.6   3.1
 28000 -40.7 -41.3  335 106 55   7.3   4.0 | -40.0 -40.0  335 120 62   5.6   3.1
 27000 -38.5 -37.3  330  98 50   7.3   4.0 | -38.3 -36.9  330 116 60   5.5   3.0
 26000 -36.2 -33.2  325  93 48   7.9   4.4 | -36.2 -33.2  330 110 57   8.0   4.4
 25000 -33.8 -28.8  325  90 46   7.9   4.4 | -33.8 -28.8  325 104 53   8.0   4.4
 24000 -31.4 -24.5  320  86 44   8.0   4.4 | -31.4 -24.5  325  98 50   7.9   4.4
 23000 -29.5 -21.1  320  87 45   5.3   2.9 | -29.4 -20.9  325  95 49   5.3   2.9
 22000 -27.9 -18.2  325  90 47   5.3   2.9 | -27.8 -18.0  330  96 49   5.3   2.9
 21000 -26.3 -15.3  330  94 48   5.1   2.8 | -26.2 -15.2  330  97 50   5.3   2.9
 20000 -24.5 -12.1  330  89 46   6.4   3.5 | -24.6 -12.3  335  91 47   5.3   2.9
 19500 -23.6 -10.5  325  86 44   6.4   3.5 | -23.9 -11.0  330  87 45   5.3   2.9
 19000 -22.6  -8.7  325  82 42   6.4   3.5 | -23.1  -9.6  330  83 43   5.3   2.9
 18500 -21.7  -7.1  325  78 40   6.4   3.5 | -22.3  -8.1  330  79 41   5.5   3.0
 18000 -20.7  -5.3  325  76 39   7.7   4.2 | -21.6  -6.9  330  74 38   2.8   1.5
 17500 -19.5  -3.1  325  75 39   7.6   4.2 | -21.3  -6.3  330  68 35   2.5   1.4
 17000 -18.4  -1.1  325  74 38   6.6   3.6 | -20.9  -5.6  330  61 32   3.8   2.1
 16500 -17.6   0.3  325  72 37   5.4   3.0 | -20.1  -4.2  330  58 30   6.6   3.6
 16000 -16.8   1.8  330  70 36   5.4   3.0 | -19.1  -2.4  330  55 28   6.7   3.7
 15500 -16.0   3.2  330  66 34   5.6   3.1 | -18.1  -0.6  330  51 26   7.3   4.0
 15000 -15.1   4.8  330  62 32   5.7   3.1 | -17.0   1.4  330  48 25   7.3   4.0
 14500 -14.1   6.6  330  53 27   4.4   2.4 | -15.5   4.1  330  42 22   6.5   3.5
 14000 -13.4   7.9  325  46 24   4.5   2.5 | -14.6   5.7  325  38 20   6.5   3.6
 13500 -12.7   9.1  320  40 21   5.3   2.9 | -13.6   7.5  325  34 18   6.6   3.6
 13000 -11.9  10.6  320  35 18   5.3   2.9 | -12.7   9.1  325  31 16   6.5   3.6
 12500 -11.1  12.0  315  29 15   5.5   3.0 | -11.8  10.8  320  28 14   5.8   3.2
 12000 -10.3  13.5  310  24 12   5.5   3.0 | -11.0  12.2  315  25 13   5.8   3.2
 11500  -9.6  14.7  310  20 10   5.3   2.9 | -10.1  13.8  315  23 12   5.8   3.2
 11000  -8.8  16.2  310  16  8   5.4   3.0 |  -9.3  15.3  310  21 11   5.9   3.2
 10500  -8.0  17.6  310  13  7   5.6   3.1 |  -8.3  17.1  310  21 11   6.6   3.6
 10250  -7.6  18.3  310  13  6   5.5   3.0 |  -7.8  18.0  310  21 11   6.5   3.6
 10000  -7.1  19.2  315  12  6   7.9   4.3 |  -7.3  18.9  310  22 11   8.6   4.7
  9750  -6.5  20.3  310  11  6   8.3   4.6 |  -6.6  20.1  310  22 11   8.3   4.6
  9500  -5.9  21.4  315  11  5   6.8   3.7 |  -6.1  21.0  310  21 11   6.5   3.6
  9250  -5.4  22.3  315  10  5   7.1   3.9 |  -5.6  21.9  310  21 11   7.1   3.9
  9000  -4.9  23.2  320  10  5   7.5   4.1 |  -5.1  22.8  310  21 11   6.4   3.5
  8750  -4.3  24.3  320  10  5   7.4   4.1 |  -4.7  23.5  310  21 11   6.1   3.4
  8500  -3.8  25.2  315  10  5   6.8   3.7 |  -4.2  24.4  305  20 10   6.5   3.6
  8250  -3.3  26.1  315   9  5   7.2   4.0 |  -3.7  25.3  305  19 10   6.3   3.5
  8000  -2.8  27.0  315   9  4   7.2   4.0 |  -3.3  26.1  305  19 10   5.6   3.1
  7750  -2.3  27.9  310   8  4   5.5   3.0 |  -2.9  26.8  300  17  9   5.1   2.8
  7500  -2.0  28.4  305   7  4   4.7   2.6 |  -2.6  27.3  295  16  8   4.5   2.5
  7250  -1.6  29.1  295   6  3   4.4   2.4 |  -2.2  28.0  290  15  7   6.3   3.5
  7000  -1.3  29.7  290   6  3   3.9   2.1 |  -1.7  28.9  285  13  7   8.3   4.5
  6750  -1.0  30.2  280   5  3   4.3   2.3 |  -1.1  30.0  280  11  6   7.8   4.3
  6500  -0.7  30.7  270   5  2   4.6   2.5 |  -0.5  31.1  275  10  5   8.4   4.6
  6250  -0.4  31.3  255   4  2   4.9   2.7 |   0.1  32.2  270   9  4   9.5   5.2
  6000  -0.0  32.0  240   3  1   5.1   2.8 |   0.9  33.6  270   8  4   9.7   5.3
  5750   0.3  32.5  215   2  1   4.1   2.3 |   1.6  34.9  270   7  4   8.8   4.8
  5500   0.6  33.1  180   2  1   1.4   0.8 |   2.2  36.0  270   6  3   8.1   4.4
  5250   0.6  33.1  170   2  1  -1.0  -0.5 |   2.8  37.0  270   6  3   8.1   4.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/22/2014 at 1400 MST          |       12/22/2014 at 1700 MST
                                           |
K index... +10.6  LI... +2.3               | K index... +10.6  LI... +1.4
CAPE... +41.7  CIN... -0.8                 | CAPE... +26.0  CIN... -8.3
                                           |
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 -55.0 -67.0  330  57 29   0.4   0.2 | -56.9 -70.4  330  47 24   1.9   1.0
 45000 -54.3 -65.7  335  95 49   1.0   0.5 | -54.0 -65.2  335  80 41   1.9   1.1
 40000 -51.4 -60.5  340 112 58   2.0   1.1 | -51.0 -59.8  345 114 59   2.0   1.1
 38000 -49.9 -57.8  345 120 62   3.3   1.8 | -49.5 -57.1  345 125 64   3.7   2.0
 36000 -47.9 -54.2  340 129 67   3.3   1.8 | -47.3 -53.1  345 131 67   3.7   2.0
 34000 -45.9 -50.6  340 138 71   3.2   1.7 | -45.1 -49.2  345 137 70   3.6   1.9
 32000 -44.6 -48.3  340 134 69   2.1   1.1 | -43.7 -46.7  345 139 72   2.2   1.2
 30000 -43.2 -45.8  340 128 66   4.0   2.2 | -42.2 -44.0  340 142 73   3.7   2.0
 29000 -41.6 -42.9  340 129 66   5.3   2.9 | -40.7 -41.3  345 144 74   5.0   2.8
 28000 -40.0 -40.0  340 130 67   5.3   2.9 | -39.2 -38.6  345 147 75   5.0   2.8
 27000 -38.4 -37.1  340 131 68   5.3   2.9 | -37.7 -35.9  345 149 77   5.2   2.8
 26000 -36.4 -33.5  340 131 67   7.8   4.3 | -35.7 -32.3  345 149 77   8.1   4.4
 25000 -34.0 -29.2  340 129 66   7.9   4.3 | -33.2 -27.8  345 146 75   8.2   4.5
 24000 -31.7 -25.1  335 126 65   7.9   4.3 | -30.8 -23.4  345 143 74   8.1   4.4
 23000 -29.7 -21.5  335 121 62   5.0   2.7 | -28.9 -20.0  345 135 70   3.4   1.9
 22000 -28.2 -18.8  340 112 57   5.0   2.7 | -27.8 -18.0  345 120 62   3.6   2.0
 21000 -26.7 -16.1  340 102 53   5.1   2.8 | -26.7 -16.1  345 105 54   3.6   2.0
 20000 -25.3 -13.5  340  91 47   4.0   2.2 | -26.1 -15.0  345  91 47   0.8   0.4
 19500 -24.7 -12.5  340  86 44   4.0   2.2 | -26.0 -14.8  345  84 43   0.7   0.4
 19000 -24.1 -11.4  340  80 41   4.0   2.2 | -25.9 -14.6  345  77 40   0.7   0.4
 18500 -23.5 -10.3  340  74 38   4.0   2.2 | -25.8 -14.4  345  71 36   0.7   0.4
 18000 -22.9  -9.2  340  68 35   4.4   2.4 | -25.7 -14.3  345  64 33   1.9   1.1
 17500 -22.2  -8.0  340  63 32   4.6   2.5 | -25.3 -13.5  345  57 29   3.0   1.6
 17000 -21.5  -6.7  340  58 30   4.6   2.5 | -24.8 -12.6  345  49 25   3.6   2.0
 16500 -20.9  -5.6  340  54 28   4.4   2.4 | -23.9 -11.0  345  43 22   8.2   4.5
 16000 -20.2  -4.4  335  49 25   4.4   2.4 | -22.8  -9.0  340  38 20   8.0   4.4
 15500 -19.5  -3.1  335  45 23   6.6   3.6 | -21.6  -6.9  340  35 18   7.9   4.3
 15000 -18.6  -1.5  335  41 21   6.5   3.6 | -20.4  -4.7  340  34 18   7.9   4.3
 14500 -17.1   1.2  330  36 19   6.7   3.7 | -18.7  -1.7  335  33 17   7.9   4.3
 14000 -16.1   3.0  330  33 17   6.7   3.7 | -17.5   0.5  340  31 16   7.9   4.4
 13500 -15.1   4.8  330  30 16   8.0   4.4 | -16.3   2.7  340  32 16   8.3   4.5
 13000 -13.9   7.0  325  28 14   7.9   4.3 | -15.1   4.8  340  33 17   8.3   4.5
 12500 -12.7   9.1  325  27 14   8.0   4.4 | -13.9   7.0  340  33 17   8.1   4.4
 12000 -11.5  11.3  325  27 14   8.0   4.4 | -12.7   9.1  340  31 16   8.1   4.4
 11500 -10.4  13.3  325  27 14   7.3   4.0 | -11.5  11.3  340  30 16   8.3   4.6
 11000  -9.3  15.3  325  26 13   7.4   4.0 | -10.2  13.6  345  30 16   8.3   4.5
 10500  -8.3  17.1  320  25 13   6.6   3.6 |  -9.1  15.6  340  30 15   7.1   3.9
 10250  -7.8  18.0  320  26 13   6.8   3.7 |  -8.6  16.5  340  30 15   7.2   3.9
 10000  -7.2  19.0  320  26 13   9.3   5.1 |  -8.0  17.6  340  29 15   9.8   5.4
  9750  -6.5  20.3  315  26 13   8.9   4.9 |  -7.2  19.0  340  29 15   9.8   5.4
  9500  -6.0  21.2  315  25 13   7.0   3.8 |  -6.6  20.1  340  29 15   7.9   4.3
  9250  -5.4  22.3  315  25 13   7.7   4.2 |  -6.0  21.2  340  29 15   8.6   4.7
  9000  -4.9  23.2  310  25 13   6.7   3.7 |  -5.4  22.3  335  29 15   7.6   4.2
  8750  -4.4  24.1  310  23 12   6.4   3.5 |  -4.8  23.4  335  27 14   7.5   4.1
  8500  -3.9  25.0  305  22 11   6.9   3.8 |  -4.2  24.4  335  26 14   8.3   4.5
  8250  -3.5  25.7  300  20 10   7.0   3.8 |  -3.6  25.5  335  25 13   8.3   4.6
  8000  -2.9  26.8  295  19 10   8.3   4.5 |  -3.0  26.6  335  24 13   9.4   5.2
  7750  -2.3  27.9  295  18  9   8.7   4.8 |  -2.3  27.9  330  24 12   9.3   5.1
  7500  -1.7  28.9  295  17  9   7.9   4.4 |  -1.6  29.1  330  23 12   8.6   4.7
  7250  -1.1  30.0  290  16  8   9.2   5.0 |  -1.0  30.2  330  22 11   9.0   5.0
  7000  -0.4  31.3  290  16  8  10.5   5.8 |  -0.3  31.5  330  22 11   9.2   5.1
  6750   0.4  32.7  290  15  8   9.8   5.4 |   0.4  32.7  325  21 11   9.0   4.9
  6500   1.1  34.0  290  14  7   9.7   5.3 |   1.0  33.8  325  20 10   8.6   4.7
  6250   1.9  35.4  290  14  7  10.8   5.9 |   1.7  35.1  325  18  9   8.4   4.6
  6000   2.7  36.9  290  13  7  11.0   6.0 |   2.3  36.1  325  17  9   7.5   4.1
  5750   3.5  38.3  285  12  6   9.9   5.4 |   2.7  36.9  325  14  7   4.0   2.2
  5500   4.1  39.4  285  10  5   8.4   4.6 |   2.8  37.0  320   9  5  -0.4  -0.2
  5250   4.7  40.5  285  10  5   7.4   4.1 |   2.7  36.9  320   9  5  -1.8  -1.0
  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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