Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231235
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0535 MST Monday, January 23, 2017

This forecast is for Monday, January 23, 2017:

If the trigger temperature of 45.6 F/7.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6479 ft MSL (1640 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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 01/24...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:27:19 / 17:23:56 MST
Total possible sunshine........... 9 hr 56 min 38 sec (596 min 38 sec)
Altitude of sun at 12:26:01 MST... 31.68 degrees

Upper air data from rawinsonde observation taken on 01/23/2017 at 0500 MST

Freezing level.................. 6981 ft MSL (2142 ft AGL)
Convective condensation level... 11868 ft MSL (7029 ft AGL)
Lifted condensation level....... 9657 ft MSL (4818 ft AGL)
Lifted index.................... +10.7
K index......................... +13.7

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  -56.4 -69.5   245   63   32  -0.7  -0.4  108.0 226.3    58.3      M    M
 45000  -53.8 -64.8   260   87   45   4.8   2.6   86.2 187.2    49.3      M    M
 40000  -49.0 -56.2   255  126   65   1.0   0.5   70.7 159.2    42.4      M    M
 38000  -53.5 -64.3   250  144   74   4.6   2.5   55.2 131.3    33.2      M    M
 36000  -50.4 -58.7   245  150   77   5.2   2.9   51.1 123.9    31.3      M    M
 34000  -49.0 -56.2   245  157   81  12.6   6.9   44.7 112.4    27.6      M    M
 32000  -44.5 -48.1   250  154   79   4.0   2.2   41.8 107.2    26.3      M    M
 30000  -41.2 -42.2   250  152   78   8.3   4.5   38.3 101.0    24.4      M    M
 29000  -39.1 -38.4   250  153   79   6.1   3.4   37.2  99.0    23.9      M    M
 28000  -37.2 -35.0   250  146   75   6.3   3.5   35.8  96.5    23.1      M    M
 27000  -35.8 -32.4   250  140   72   3.3   1.8   33.9  93.1    21.9      M    M
 26000  -33.9 -29.0   255  133   69   6.5   3.5   32.6  90.6    21.1      M    M
 25000  -32.4 -26.3   255  127   65   4.9   2.7   30.8  87.4    20.0      M    M
 24000  -30.9 -23.6   255  126   65   5.5   3.0   29.0  84.1    18.8      M    M
 23000  -30.3 -22.5   260  118   61   1.8   1.0   26.0  78.9    16.6      M    M
 22000  -29.8 -21.6   260  107   55   1.8   1.0   23.1  73.5    14.4      M    M
 21000  -28.7 -19.7   260   97   50   7.4   4.0   20.9  69.6    12.7      M    M
 20000  -26.8 -16.2   260   86   44   6.2   3.4   19.8  67.6    11.9      M    M
 19500  -25.9 -14.6   260   78   40   6.7   3.7   19.1  66.4    11.4      M    M
 19000  -24.7 -12.5   255   70   36   8.5   4.7   18.8  65.9    11.2      M    M
 18500  -23.6 -10.5   255   68   35   6.5   3.6   18.5  65.3    11.0      M    M
 18000  -22.7  -8.9   255   67   34   7.1   3.9   17.8  64.0    10.4      M    M
 17500  -21.0  -5.8   250   65   33   9.6   5.3   17.2  62.9    10.0      M    M
 17000  -19.3  -2.7   250   64   33   8.9   4.9   17.6  63.6    10.4      M    M
 16500  -18.5  -1.3   245   63   32   6.2   3.4   16.8  62.3     9.7      M    M
 16000  -17.5   0.5   245   62   32   7.0   3.9   16.4  61.5     9.3      M    M
 15500  -16.4   2.5   245   63   32   6.2   3.4   15.9  60.7     9.0      M    M
 15000  -15.7   3.7   245   64   33   3.6   2.0   15.1  59.2     8.3      M    M
 14500  -14.6   5.7   245   64   33  12.4   6.8   14.7  58.5     7.9      M    M
 14000  -13.4   7.9   245   64   33   4.9   2.7   14.5  58.1     7.8      M    M
 13500  -12.6   9.3   245   61   31   5.1   2.8   13.8  56.8     7.1      M    M
 13000  -11.8  10.8   245   57   29   6.0   3.3   13.0  55.5     6.5      M    M
 12500  -10.9  12.4   240   53   27   6.1   3.4   12.5  54.4     5.9      M    M
 12000  -10.0  14.0   240   49   25   6.2   3.4   11.9  53.4     5.4      M    M
 11500   -9.1  15.6   240   45   23   6.4   3.5   11.3  52.3     4.9      M    M
 11000   -8.4  16.9   240   42   22   3.7   2.0   10.5  50.9     4.2      M    M
 10500   -7.8  18.0   235   35   18   3.9   2.1    9.6  49.3     3.3      M    M
 10250   -7.5  18.5   235   32   17   4.1   2.3    9.1  48.4     2.9      M    M
 10000   -7.1  19.2   230   29   15   6.7   3.7    8.8  47.8     2.6      M    M
  9750   -6.5  20.3   225   26   14   8.2   4.5    8.6  47.5     2.4      M    M
  9500   -6.0  21.2   220   24   13   7.6   4.2    8.5  47.2     2.3      M    M
  9250   -5.4  22.3   220   23   12   7.8   4.3    8.3  47.0     2.2      M    M
  9000   -4.8  23.4   215   21   11   7.7   4.2    8.2  46.7     2.0      M    M
  8750   -4.2  24.4   210   21   11   7.7   4.2    8.0  46.4     1.9      M    M
  8500   -3.6  25.5   210   20   10   7.7   4.2    7.8  46.1     1.7      M    M
  8250   -3.0  26.6   205   20   10   7.7   4.3    7.7  45.8     1.6      M    M
  8000   -2.5  27.5   200   20   10   7.7   4.2    7.5  45.6     1.5      M    M
  7750   -1.9  28.6   200   19   10   7.7   4.2    7.4  45.3     1.3      M    M
  7500   -1.3  29.7   195   18    9   7.7   4.2    7.2  45.0     1.2      M    M
  7250   -0.7  30.7   195   17    9   7.5   4.1    7.1  44.7     1.0      M    M
  7000   -0.2  31.6   190   16    8   8.1   4.5    6.9  44.4     0.9      M    M
  6750    0.4  32.7   180   18    9   5.9   3.2    6.7  44.1     0.7      M    M
  6500    0.7  33.3   175   21   11   2.0   1.1    6.3  43.3     0.2      M    M
  6250    0.7  33.3   165   24   12   1.5   0.8    5.6  42.1    -0.4     36  0.2
  6000    0.9  33.6   160   27   14   6.2   3.4    5.1  41.3    -0.9     23  0.1
  5750    1.6  34.9   160   25   13   9.0   5.0    5.1  41.1    -1.1      M    M
  5500    2.2  36.0   155   21   11   9.0   4.9    5.0  40.9    -1.2      M    M
  5250    2.8  37.0   145   17    9   4.2   2.3    4.8  40.7    -1.3      M    M
  5000    2.7  36.9   135   14    7  -6.2  -3.4    4.0  39.2    -2.1      M    M

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

           01/23/2017 at 0800 MST          |       01/23/2017 at 1100 MST
                                           |
K index... +13.2  LI... +1.3               | K index... +17.2  LI... +1.4
CAPE... +26.8  CIN... -4.7                 | CAPE... +20.8  CIN... -12.3
                                           |
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 -58.9 -74.0  240  45 23   3.9   2.1 | -57.5 -71.5  235  40 20   3.9   2.1
 45000 -53.1 -63.6  255  88 45   4.1   2.2 | -51.6 -60.9  250  67 34   4.2   2.3
 40000 -49.7 -57.5  250 113 58   2.2   1.2 | -49.6 -57.3  245 100 51   1.2   0.7
 38000 -48.7 -55.7  250 123 64   0.2   0.1 | -49.0 -56.2  245 112 58   0.8   0.4
 36000 -48.6 -55.5  250 130 67   0.2   0.1 | -48.4 -55.1  245 122 63   0.8   0.4
 34000 -48.5 -55.3  250 137 70   0.8   0.5 | -48.0 -54.4  245 131 67   0.6   0.3
 32000 -46.0 -50.8  250 141 73   4.5   2.5 | -45.7 -50.3  245 138 71   4.2   2.3
 30000 -43.2 -45.8  250 146 75   4.7   2.6 | -43.2 -45.8  245 145 75   4.0   2.2
 29000 -41.6 -42.9  250 141 73   5.4   3.0 | -41.6 -42.9  245 144 74   5.5   3.0
 28000 -40.0 -40.0  255 135 70   5.4   3.0 | -40.0 -40.0  245 142 73   5.5   3.0
 27000 -38.4 -37.1  255 129 67   5.4   3.0 | -38.3 -36.9  245 140 72   5.5   3.0
 26000 -36.6 -33.9  255 124 64   6.8   3.7 | -36.7 -34.1  245 137 71   5.6   3.1
 25000 -34.6 -30.3  255 119 61   6.7   3.7 | -35.0 -31.0  245 130 67   5.6   3.1
 24000 -32.6 -26.7  255 115 59   6.7   3.7 | -33.3 -27.9  245 122 63   5.6   3.1
 23000 -30.6 -23.1  255 109 56   6.2   3.4 | -31.7 -25.1  245 114 59   4.8   2.6
 22000 -28.8 -19.8  255 100 51   6.2   3.4 | -30.3 -22.5  245 102 53   4.6   2.5
 21000 -26.4 -15.5  250  88 45   6.3   3.4 | -28.9 -20.0  240  91 47   4.6   2.5
 20000 -24.8 -12.6  250  78 40   5.2   2.9 | -26.9 -16.4  235  77 40   6.5   3.6
 19500 -24.0 -11.2  245  73 38   5.2   2.9 | -25.9 -14.6  235  72 37   6.6   3.6
 19000 -23.2  -9.8  245  68 35   5.3   2.9 | -24.9 -12.8  235  67 34   6.6   3.6
 18500 -22.4  -8.3  245  63 33   5.2   2.9 | -23.9 -11.0  235  62 32   6.6   3.6
 18000 -21.6  -6.9  240  58 30   6.0   3.3 | -23.0  -9.4  230  57 30   5.7   3.1
 17500 -20.7  -5.3  235  52 27   6.3   3.4 | -22.2  -8.0  235  56 29   5.1   2.8
 17000 -19.8  -3.6  230  46 24   6.3   3.5 | -21.5  -6.7  235  54 28   5.0   2.8
 16500 -18.9  -2.0  230  45 23   6.2   3.4 | -20.9  -5.6  240  55 28   4.0   2.2
 16000 -17.9  -0.2  230  44 23   6.2   3.4 | -20.3  -4.5  245  58 30   3.7   2.0
 15500 -17.1   1.2  235  45 23   5.8   3.2 | -19.5  -3.1  245  59 30   8.1   4.5
 15000 -16.2   2.8  235  48 25   5.8   3.2 | -18.3  -0.9  245  58 30   8.1   4.4
 14500 -15.3   4.5  240  51 26   6.6   3.6 | -17.0   1.4  245  56 29   8.9   4.9
 14000 -14.3   6.3  245  53 27   6.7   3.7 | -15.7   3.7  245  55 28   9.2   5.0
 13500 -13.3   8.1  245  56 29   7.9   4.3 | -14.3   6.3  245  54 28   8.9   4.9
 13000 -12.1  10.2  245  56 29   8.4   4.6 | -13.1   8.4  245  54 28   8.6   4.7
 12500 -10.8  12.6  245  56 29   8.3   4.6 | -11.8  10.8  245  55 28   8.3   4.6
 12000  -9.7  14.5  245  56 29   8.2   4.5 | -10.6  12.9  245  54 28   8.0   4.4
 11500  -8.5  16.7  245  56 29   7.8   4.3 |  -9.4  15.1  245  53 28   7.7   4.2
 11000  -7.4  18.7  245  55 28   7.5   4.1 |  -8.4  16.9  245  51 26   7.2   4.0
 10500  -6.3  20.7  245  53 27   7.0   3.8 |  -7.3  18.9  240  49 25   7.3   4.0
 10250  -5.8  21.6  245  52 27   6.5   3.5 |  -6.8  19.8  240  48 25   7.5   4.1
 10000  -5.3  22.5  245  50 26   6.9   3.8 |  -6.2  20.8  240  46 24   7.5   4.1
  9750  -4.8  23.4  240  49 25   7.0   3.8 |  -5.7  21.7  240  45 23   7.5   4.1
  9500  -4.3  24.3  240  48 25   6.1   3.3 |  -5.1  22.8  240  43 22   7.3   4.0
  9250  -3.9  25.0  235  46 23   5.8   3.2 |  -4.6  23.7  235  41 21   7.3   4.0
  9000  -3.5  25.7  235  43 22   5.4   2.9 |  -4.1  24.6  235  39 20   6.6   3.6
  8750  -3.2  26.2  230  41 21   3.8   2.1 |  -3.7  25.3  230  37 19   5.3   2.9
  8500  -2.9  26.8  230  39 20   3.2   1.7 |  -3.3  26.1  230  35 18   5.5   3.0
  8250  -2.6  27.3  225  37 19   3.8   2.1 |  -2.8  27.0  225  32 17   6.1   3.3
  8000  -2.4  27.7  220  35 18   2.3   1.2 |  -2.4  27.7  225  30 15   5.3   2.9
  7750  -2.3  27.9  220  33 17   2.4   1.3 |  -2.0  28.4  220  28 14   4.7   2.6
  7500  -2.0  28.4  215  30 16   4.0   2.2 |  -1.7  28.9  215  26 13   5.1   2.8
  7250  -1.7  28.9  210  28 14   3.3   1.8 |  -1.3  29.7  210  23 12   4.8   2.6
  7000  -1.4  29.5  205  26 13   4.5   2.4 |  -0.9  30.4  205  22 11   5.7   3.1
  6750  -1.1  30.0  195  24 13   5.4   3.0 |  -0.5  31.1  195  20 10   7.0   3.8
  6500  -0.7  30.7  195  22 11   5.3   2.9 |   0.0  32.0  195  18  9   6.9   3.8
  6250  -0.3  31.5  185  20 11   5.0   2.8 |   0.5  32.9  190  17  9   7.1   3.9
  6000  -0.0  32.0  180  19 10   2.3   1.3 |   1.0  33.8  180  15  8   5.9   3.2
  5750  -0.0  32.0  175  16  8  -1.7  -0.9 |   1.4  34.5  180  13  7   6.9   3.8
  5500  -0.2  31.6  170  13  7  -3.7  -2.0 |   2.1  35.8  175  12  6  12.0   6.6
  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

           01/23/2017 at 1400 MST          |       01/23/2017 at 1700 MST
                                           |
K index... +16.3  LI... -0.7               | K index... +12.0  LI... -1.1
CAPE... +79.8  CIN... -2.2                 | CAPE... +142.9  CIN... -3.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.6 -68.1  235  36 18   4.6   2.5 | -53.6 -64.5  245  40 20   3.7   2.0
 45000 -48.7 -55.7  240  56 29   4.8   2.6 | -47.7 -53.9  225  46 24   3.7   2.0
 40000 -47.6 -53.7  240  92 47   0.5   0.2 | -46.5 -51.7  235  84 43   0.5   0.3
 38000 -47.4 -53.3  240 106 54  -0.1  -0.1 | -46.3 -51.3  240  99 51  -0.7  -0.4
 36000 -47.4 -53.3  245 116 59  -0.1  -0.0 | -46.8 -52.2  240 107 55  -0.9  -0.5
 34000 -47.4 -53.3  245 125 64  -0.2  -0.1 | -47.3 -53.1  240 114 59  -0.9  -0.5
 32000 -45.6 -50.1  245 136 70   3.8   2.1 | -45.8 -50.4  240 123 63   3.9   2.2
 30000 -43.3 -45.9  245 147 76   3.8   2.1 | -43.4 -46.1  240 132 68   3.9   2.2
 29000 -41.8 -43.2  245 149 77   5.8   3.2 | -42.2 -44.0  240 133 68   4.4   2.4
 28000 -40.0 -40.0  245 147 76   5.9   3.2 | -40.9 -41.6  240 129 66   4.4   2.4
 27000 -38.3 -36.9  245 146 75   5.9   3.2 | -39.5 -39.1  240 124 64   4.4   2.4
 26000 -36.6 -33.9  245 143 74   4.6   2.5 | -38.2 -36.8  240 120 62   3.9   2.1
 25000 -35.4 -31.7  245 129 67   4.0   2.2 | -37.4 -35.3  240 106 54   2.5   1.4
 24000 -34.2 -29.6  245 115 59   4.0   2.2 | -36.6 -33.9  240  91 47   2.5   1.4
 23000 -33.0 -27.4  245 101 52   3.4   1.8 | -35.9 -32.6  235  77 39   2.7   1.5
 22000 -32.2 -26.0  240  89 46   2.4   1.3 | -34.8 -30.6  230  72 37   3.8   2.1
 21000 -31.5 -24.7  240  77 40   2.4   1.3 | -33.7 -28.7  230  69 36   3.8   2.1
 20000 -29.9 -21.8  235  66 34   7.6   4.2 | -32.4 -26.3  225  66 34   6.4   3.5
 19500 -28.8 -19.8  235  64 33   7.6   4.2 | -31.4 -24.5  225  65 33   7.3   4.0
 19000 -27.7 -17.9  235  62 32   7.7   4.2 | -29.7 -21.5  225  62 32   7.4   4.0
 18500 -26.6 -15.9  235  59 31   7.7   4.2 | -28.6 -19.5  225  60 31   7.4   4.0
 18000 -25.4 -13.7  235  57 29   7.6   4.2 | -27.6 -17.7  225  59 30   7.5   4.1
 17500 -24.3 -11.7  235  54 28   7.2   4.0 | -26.4 -15.5  225  56 29   8.3   4.6
 17000 -23.3  -9.9  235  52 27   7.2   4.0 | -25.1 -13.2  220  54 28   8.3   4.5
 16500 -22.2  -8.0  235  50 26   7.8   4.3 | -23.9 -11.0  220  51 26   8.7   4.7
 16000 -21.0  -5.8  235  48 25   7.8   4.3 | -22.6  -8.7  225  48 25   8.7   4.8
 15500 -19.9  -3.8  235  46 24   7.8   4.3 | -21.3  -6.3  225  45 23   7.8   4.3
 15000 -18.7  -1.7  235  45 23   7.8   4.3 | -20.3  -4.5  225  49 25   7.1   3.9
 14500 -17.5   0.5  235  43 22   7.7   4.2 | -19.2  -2.6  230  52 27   7.0   3.8
 14000 -16.4   2.5  235  46 24   7.6   4.2 | -18.2  -0.8  235  53 27   6.8   3.7
 13500 -15.3   4.5  235  50 26   7.7   4.2 | -17.2   1.0  235  54 28   6.9   3.8
 13000 -14.2   6.4  235  50 26   7.8   4.3 | -16.1   3.0  235  53 27   7.5   4.1
 12500 -13.0   8.6  235  50 26   7.7   4.2 | -15.0   5.0  235  51 26   7.5   4.1
 12000 -11.9  10.6  235  50 26   7.7   4.2 | -13.9   7.0  240  49 25   7.4   4.0
 11500 -10.8  12.6  235  49 25   7.7   4.2 | -12.9   8.8  240  48 25   7.4   4.1
 11000  -9.6  14.7  235  47 24   7.8   4.3 | -11.7  10.9  240  47 24   7.9   4.4
 10500  -8.5  16.7  230  45 23   7.8   4.3 | -10.6  12.9  245  45 23   8.2   4.5
 10250  -7.9  17.8  230  43 22   7.9   4.4 |  -9.9  14.2  245  44 22   9.9   5.4
 10000  -7.3  18.9  230  41 21   7.6   4.2 |  -9.2  15.4  245  42 22   9.2   5.0
  9750  -6.8  19.8  225  40 20   7.2   3.9 |  -8.6  16.5  245  41 21   7.7   4.2
  9500  -6.3  20.7  225  38 20   7.4   4.1 |  -8.0  17.6  245  40 21   8.3   4.6
  9250  -5.7  21.7  225  36 19   7.7   4.2 |  -7.4  18.7  245  39 20   8.6   4.7
  9000  -5.2  22.6  220  34 18   7.4   4.1 |  -6.7  19.9  245  37 19   8.8   4.8
  8750  -4.6  23.7  220  33 17   6.8   3.7 |  -6.1  21.0  245  36 18   9.2   5.1
  8500  -4.1  24.6  220  31 16   7.4   4.0 |  -5.4  22.3  245  34 18   9.2   5.0
  8250  -3.6  25.5  215  29 15   8.2   4.5 |  -4.7  23.5  245  33 17   9.0   4.9
  8000  -3.0  26.6  215  27 14   7.3   4.0 |  -4.1  24.6  240  31 16   9.0   5.0
  7750  -2.5  27.5  210  25 13   5.8   3.2 |  -3.4  25.9  240  29 15   8.7   4.8
  7500  -2.1  28.2  210  24 12   7.1   3.9 |  -2.8  27.0  240  28 14   8.7   4.8
  7250  -1.5  29.3  205  22 11   8.4   4.6 |  -2.2  28.0  240  26 13   9.0   5.0
  7000  -0.9  30.4  205  20 11   8.5   4.6 |  -1.5  29.3  240  24 12   8.3   4.5
  6750  -0.2  31.6  200  19 10   8.9   4.9 |  -1.0  30.2  240  22 11   8.0   4.4
  6500   0.4  32.7  200  17  9   8.6   4.7 |  -0.3  31.5  240  19 10   8.5   4.7
  6250   1.0  33.8  200  16  8   8.7   4.8 |   0.3  32.5  240  17  9   8.5   4.6
  6000   1.7  35.1  200  15  7   8.7   4.8 |   0.9  33.6  245  15  8   8.2   4.5
  5750   2.3  36.1  200  14  7  10.1   5.6 |   1.4  34.5  240  14  7   5.8   3.2
  5500   3.1  37.6  200  12  6  12.5   6.9 |   1.7  35.1  240  12  6   2.7   1.5
  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
________________________________________________________________________________

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.

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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