Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 171234
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0634 MDT Tuesday, April 17, 2018

This forecast is for Tuesday, April 17, 2018:

If the trigger temperature of 60.1 F/15.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7785 ft MSL (2946 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. None
Thermal soaring outlook for Wednesday 04/18.... Good

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

Remarks...

Sunrise/Sunset.................... 06:34:27 / 19:52:37 MDT
Total possible sunshine........... 13 hr 18 min 10 sec (798 min 10 sec)
Altitude of sun at 13:13:41 MDT... 61.55 degrees

Upper air data from rawinsonde observation taken on 04/17/2018 at 0600 MDT

Freezing level.................. 10185 ft MSL (5346 ft AGL)
Convective condensation level... 17962 ft MSL (13123 ft AGL)
Lifted condensation level....... 16815 ft MSL (11976 ft AGL)
Lifted index.................... +7.4
K index......................... +5.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -48.5 -55.3   220   33   17   8.9   4.9  119.1 246.4    59.3      M    M
 45000  -51.9 -61.4   235   85   44   4.2   2.3   88.6 191.6    44.7      M    M
 40000  -50.7 -59.3   240   89   46  -2.0  -1.1   67.5 153.5    33.9      M    M
 38000  -51.9 -61.4   240   98   50  -4.9  -2.7   56.8 134.3    27.7      M    M
 36000  -54.9 -66.8   235  115   59 -16.5  -9.1   43.7 110.7    19.4      M    M
 34000  -51.9 -61.4   230  123   63   4.3   2.3   38.6 101.5    16.4      M    M
 32000  -47.6 -53.7   225  122   63   7.4   4.1   36.4  97.5    15.2      M    M
 30000  -43.1 -45.6   225  122   63   7.2   4.0   34.8  94.6    14.4      M    M
 29000  -41.0 -41.8   225  120   62   7.2   4.0   33.7  92.6    13.7      M    M
 28000  -38.8 -37.8   225  117   60   7.3   4.0   32.7  90.9    13.1      M    M
 27000  -36.8 -34.2   225  115   59   6.2   3.4   31.4  88.6    12.3      M    M
 26000  -35.0 -31.0   225  112   58   7.0   3.8   30.1  86.2    11.4      M    M
 25000  -32.6 -26.7   225  110   57   8.2   4.5   29.5  85.1    11.1      M    M
 24000  -30.6 -23.1   225  107   55   5.1   2.8   28.2  82.8    10.2      M    M
 23000  -28.1 -18.6   225  105   54   8.5   4.7   27.7  81.8     9.9      M    M
 22000  -25.5 -13.9   220  105   54   8.6   4.7   27.2  81.0     9.6      M    M
 21000  -23.2  -9.8   220  105   54   3.5   1.9   26.6  79.9     9.2      M    M
 20000  -23.1  -9.6   220   97   50  -5.3  -2.9   23.2  73.8     6.5      M    M
 19500  -23.1  -9.6   220   93   48   7.7   4.2   21.6  70.8     5.1      M    M
 19000  -21.8  -7.2   220   89   46   7.2   3.9   21.3  70.3     4.9      M    M
 18500  -21.2  -6.2   220   84   43   3.1   1.7   19.6  67.2     3.4      M    M
 18000  -20.4  -4.7   220   79   41   6.5   3.6   18.8  65.8     2.7      M    M
 17500  -19.5  -3.1   220   74   38   6.3   3.5   18.2  64.7     2.2      M    M
 17000  -18.6  -1.5   225   69   35   6.3   3.4   17.6  63.7     1.6      M    M
 16500  -17.6   0.3   225   63   33   7.3   4.0   17.1  62.7     1.2      M    M
 16000  -16.5   2.3   225   59   30   7.5   4.1   16.7  62.0     0.8      M    M
 15500  -15.4   4.3   225   57   29   8.3   4.5   16.3  61.3     0.5      M    M
 15000  -14.0   6.8   225   55   28   9.5   5.2   16.2  61.2     0.4      M    M
 14500  -12.5   9.5   225   54   28   9.7   5.3   16.2  61.1     0.4      M    M
 14000  -11.1  12.0   225   54   28   9.8   5.4   16.2  61.2     0.4      M    M
 13500   -9.6  14.7   225   53   27   9.8   5.4   16.2  61.1     0.4      M    M
 13000   -8.2  17.2   220   53   27   9.8   5.4   16.2  61.2     0.4      M    M
 12500   -6.7  19.9   220   52   27   9.8   5.4   16.2  61.2     0.4      M    M
 12000   -5.3  22.5   220   52   27   9.8   5.4   16.3  61.3     0.4      M    M
 11500   -3.8  25.2   220   51   26   9.8   5.4   16.2  61.2     0.4      M    M
 11000   -2.3  27.9   220   50   26   9.8   5.4   16.2  61.1     0.4      M    M
 10500   -0.9  30.4   220   49   25   9.7   5.3   16.2  61.1     0.3      M    M
 10250   -0.2  31.6   220   49   25   8.7   4.8   16.2  61.1     0.3      M    M
 10000    0.4  32.7   220   48   25   7.7   4.3   16.0  60.8     0.2      M    M
  9750    1.0  33.8   215   46   24   8.9   4.9   15.9  60.6     0.1      M    M
  9500    1.8  35.2   215   43   22   9.7   5.3   15.9  60.6     0.1      M    M
  9250    2.5  36.5   210   40   21   9.5   5.2   15.9  60.6     0.1      M    M
  9000    3.2  37.8   210   37   19   9.6   5.2   15.9  60.6     0.1      M    M
  8750    3.9  39.0   210   35   18   9.5   5.2   15.9  60.6     0.0      M    M
  8500    4.6  40.3   210   33   17   9.5   5.2   15.9  60.5     0.0      M    M
  8250    5.3  41.5   205   31   16   9.5   5.2   15.9  60.5     0.0      M    M
  8000    6.0  42.8   205   29   15   9.5   5.2   15.8  60.5     0.0      M    M
  7750    6.7  44.1   205   30   15   9.5   5.2   15.8  60.5     0.0      M    M
  7500    7.5  45.5   205   31   16   9.5   5.2   15.8  60.5    -0.0    114  0.6
  7250    8.2  46.8   200   32   16   9.5   5.2   15.8  60.4    -0.0     85  0.4
  7000    8.9  48.0   200   33   17   9.5   5.2   15.8  60.4    -0.0     56  0.3
  6750    9.6  49.3   200   33   17   9.5   5.2   15.8  60.4    -0.1     28  0.1
  6500   10.3  50.5   200   33   17   9.6   5.2   15.7  60.3    -0.1      M    M
  6250   11.0  51.8   200   32   17   9.5   5.2   15.7  60.3    -0.1      M    M
  6000   11.7  53.1   200   32   17   9.7   5.3   15.7  60.2    -0.2      M    M
  5750   12.4  54.3   200   29   15   8.8   4.8   15.7  60.2    -0.2      M    M
  5500   13.1  55.6   195   25   13   8.0   4.4   15.5  60.0    -0.3      M    M
  5250   13.7  56.7   195   21   11   8.5   4.7   15.4  59.8    -0.4      M    M
  5000   14.3  57.7   190   18    9   7.2   3.9   15.3  59.6    -0.5      M    M

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

           04/17/2018 at 0900 MDT          |       04/17/2018 at 1200 MDT
                                           |
K index... +4.1  LI... +3.4                | K index... +13.0  LI... +0.2
CAPE... +51.8  CIN... -8.3                 | CAPE... +21.7  CIN... -0.6
                                           |
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 -54.7 -66.5  225  46 24   2.6   1.4 | -53.1 -63.6  235  63 32   2.5   1.4
 45000 -50.9 -59.6  235  72 37   2.6   1.4 | -49.2 -56.6  235  74 38   1.7   0.9
 40000 -50.3 -58.5  245  88 45   0.3   0.2 | -47.7 -53.9  250  79 41   1.0   0.5
 38000 -49.9 -57.8  245  95 49   1.1   0.6 | -47.1 -52.8  250  85 44   0.9   0.5
 36000 -49.3 -56.7  240 104 53   1.1   0.6 | -46.6 -51.9  250  94 49   0.9   0.5
 34000 -48.6 -55.5  240 112 58   2.3   1.2 | -46.1 -51.0  245 104 54   0.6   0.3
 32000 -45.6 -50.1  240 118 61   5.2   2.8 | -43.9 -47.0  245 110 56   4.1   2.2
 30000 -42.5 -44.5  235 124 64   5.6   3.1 | -41.1 -42.0  245 115 59   5.0   2.7
 29000 -40.2 -40.4  235 125 64   8.0   4.4 | -39.2 -38.6  245 116 59   6.5   3.6
 28000 -37.8 -36.0  235 126 65   8.0   4.4 | -37.2 -35.0  245 116 60   6.5   3.6
 27000 -34.9 -30.8  235 128 66   8.0   4.4 | -35.3 -31.5  245 116 60   6.4   3.5
 26000 -32.7 -26.9  235 126 65   6.5   3.6 | -34.0 -29.2  245 111 57   0.8   0.4
 25000 -30.8 -23.4  235 123 63   6.4   3.5 | -33.7 -28.7  245  99 51   1.0   0.5
 24000 -28.9 -20.0  230 119 61   6.4   3.5 | -33.4 -28.1  250  87 45   1.0   0.6
 23000 -27.3 -17.1  230 114 59   3.4   1.9 | -33.1 -27.6  250  74 38  -0.1  -0.1
 22000 -26.3 -15.3  230 107 55   3.5   1.9 | -33.1 -27.6  255  59 31   0.0   0.0
 21000 -25.2 -13.4  225  99 51   3.5   1.9 | -33.2 -27.8  260  44 23   0.3   0.2
 20000 -24.2 -11.6  225  94 48   3.2   1.8 | -31.9 -25.4  265  35 18   8.0   4.4
 19500 -23.7 -10.7  225  92 47   3.2   1.8 | -30.7 -23.3  265  33 17   8.2   4.5
 19000 -23.2  -9.8  225  90 46   3.2   1.8 | -29.4 -20.9  270  31 16   8.2   4.5
 18500 -22.7  -8.9  225  88 45   3.3   1.8 | -28.2 -18.8  275  29 15   8.3   4.5
 18000 -22.3  -8.1  225  86 44   3.4   1.9 | -27.0 -16.6  275  27 14   8.6   4.7
 17500 -21.7  -7.1  225  83 43   3.5   1.9 | -25.7 -14.3  280  26 13   8.8   4.8
 17000 -21.2  -6.2  230  80 41   3.5   1.9 | -24.3 -11.7  280  26 13   8.7   4.8
 16500 -20.8  -5.4  230  77 40   2.6   1.4 | -23.2  -9.8  280  27 14   7.5   4.1
 16000 -20.4  -4.7  230  73 38   2.6   1.4 | -22.0  -7.6  280  29 15   7.6   4.2
 15500 -19.9  -3.8  230  69 35   4.1   2.3 | -20.9  -5.6  275  30 15   7.7   4.2
 15000 -19.3  -2.7  230  65 33   4.3   2.4 | -19.8  -3.6  275  30 16   7.7   4.2
 14500 -18.6  -1.5  230  61 32   6.3   3.4 | -18.7  -1.7  275  30 16   7.1   3.9
 14000 -17.6   0.3  230  60 31   7.3   4.0 | -17.1   1.2  275  30 15   6.9   3.8
 13500 -15.8   3.6  230  56 29   9.5   5.2 | -16.1   3.0  275  29 15   7.7   4.2
 13000 -14.5   5.9  225  51 26   9.3   5.1 | -14.9   5.2  275  29 15   7.8   4.3
 12500 -13.1   8.4  225  47 24   9.5   5.2 | -14.0   6.8  275  29 15   5.4   3.0
 12000 -11.7  10.9  225  45 23   9.5   5.2 | -13.1   8.4  275  29 15   5.5   3.0
 11500 -10.3  13.5  225  44 23   9.5   5.2 | -12.2  10.0  270  29 15   7.5   4.1
 11000  -8.9  16.0  230  42 22   9.7   5.3 | -11.1  12.0  270  29 15   7.4   4.0
 10500  -7.7  18.1  230  41 21   7.4   4.1 | -10.0  14.0  270  29 15   7.5   4.1
 10250  -7.1  19.2  230  40 20   8.1   4.4 |  -9.4  15.1  265  29 15   7.5   4.1
 10000  -6.5  20.3  230  38 20   9.5   5.2 |  -8.8  16.2  265  30 15   9.0   4.9
  9750  -5.7  21.7  225  37 19   9.4   5.1 |  -8.1  17.4  265  30 15   9.6   5.3
  9500  -5.1  22.8  230  35 18   8.4   4.6 |  -7.5  18.5  260  30 15   9.0   4.9
  9250  -4.5  23.9  230  34 17   8.9   4.9 |  -6.8  19.8  260  30 15   9.0   4.9
  9000  -3.9  25.0  230  32 17   7.8   4.3 |  -6.1  21.0  260  30 15   9.8   5.4
  8750  -3.3  26.1  230  32 16   7.4   4.0 |  -5.4  22.3  260  30 15  10.3   5.6
  8500  -2.7  27.1  230  31 16   8.4   4.6 |  -4.6  23.7  260  30 15   9.7   5.3
  8250  -2.1  28.2  230  30 15   7.4   4.0 |  -3.9  25.0  260  30 15  10.3   5.6
  8000  -1.5  29.3  230  29 15  10.5   5.7 |  -3.1  26.4  260  30 15  11.1   6.1
  7750  -0.6  30.9  235  28 15  10.8   5.9 |  -2.3  27.9  260  29 15  10.2   5.6
  7500  -0.0  32.0  235  28 14   7.9   4.3 |  -1.6  29.1  260  29 15   9.0   5.0
  7250   0.6  33.1  235  27 14   9.1   5.0 |  -0.8  30.6  260  29 15  10.2   5.6
  7000   1.4  34.5  235  27 14  10.3   5.7 |  -0.0  32.0  260  29 15  11.1   6.1
  6750   2.1  35.8  235  26 13  10.3   5.7 |   0.8  33.4  260  28 15  10.2   5.6
  6500   2.9  37.2  235  25 13   9.4   5.2 |   1.5  34.7  260  28 14  10.3   5.6
  6250   3.6  38.5  235  24 12  10.5   5.7 |   2.3  36.1  260  27 14  11.7   6.4
  6000   4.4  39.9  235  22 11  10.9   6.0 |   3.2  37.8  260  26 14  12.4   6.8
  5750   5.2  41.4  235  20 10   9.6   5.3 |   4.2  39.6  260  25 13  12.1   6.7
  5500   5.9  42.6  235  18  9   8.5   4.7 |   5.1  41.2  260  23 12  15.1   8.3
  5250   6.5  43.7  235  17  9   7.7   4.2 |   6.5  43.7  260  22 12  20.3  11.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/17/2018 at 1500 MDT          |       04/17/2018 at 1800 MDT
                                           |
K index... +19.5  LI... +0.7               | K index... +3.2  LI... +1.2
CAPE... +0.4  CIN... -3.0                  | CAPE... 0.0  CIN... 0.0
                                           |
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 -52.8 -63.0  240  60 31   2.6   1.4 | -54.5 -66.1  255  55 28   2.4   1.3
 45000 -48.9 -56.0  240  65 33   2.8   1.5 | -51.0 -59.8  265  57 29   2.1   1.2
 40000 -48.1 -54.6  260  78 40   0.4   0.2 | -52.7 -62.9  275  84 43  -1.2  -0.7
 38000 -47.6 -53.7  260  84 43   1.6   0.9 | -52.6 -62.7  275  92 47   2.2   1.2
 36000 -46.6 -51.9  265  90 46   1.6   0.9 | -51.3 -60.3  280  98 50   2.1   1.2
 34000 -45.7 -50.3  265  96 50   1.5   0.8 | -50.0 -58.0  285 105 54   4.5   2.5
 32000 -43.3 -45.9  265  94 49   4.2   2.3 | -46.2 -51.2  285 105 54   6.4   3.5
 30000 -40.8 -41.4  265  91 47   4.3   2.4 | -42.4 -44.3  285 105 54   7.3   4.0
 29000 -39.6 -39.3  260  87 45   3.0   1.6 | -39.9 -39.8  290 104 54   8.2   4.5
 28000 -38.7 -37.7  260  84 43   3.0   1.6 | -37.5 -35.5  290 104 53   8.2   4.5
 27000 -37.8 -36.0  260  80 41   2.9   1.6 | -34.4 -29.9  290 103 53   8.5   4.7
 26000 -37.6 -35.7  260  73 37  -3.4  -1.9 | -32.5 -26.5  290  98 51   5.3   2.9
 25000 -38.6 -37.5  265  59 30  -3.2  -1.8 | -30.9 -23.6  290  93 48   5.3   2.9
 24000 -39.6 -39.3  265  45 23  -3.1  -1.7 | -29.3 -20.7  290  87 45   5.2   2.8
 23000 -39.4 -38.9  265  35 18   8.4   4.6 | -29.2 -20.6  290  75 39  -3.5  -1.9
 22000 -37.1 -34.8  265  31 16   7.7   4.2 | -30.3 -22.5  290  59 31  -3.8  -2.1
 21000 -34.8 -30.6  265  27 14   7.7   4.2 | -31.5 -24.7  285  43 22  -4.8  -2.7
 20000 -32.3 -26.1  270  26 14   8.6   4.7 | -30.7 -23.3  280  34 18   5.2   2.9
 19500 -31.0 -23.8  275  27 14   8.6   4.7 | -29.9 -21.8  280  31 16   5.2   2.8
 19000 -29.7 -21.5  280  28 15   8.6   4.7 | -29.1 -20.4  280  28 14   5.2   2.8
 18500 -28.4 -19.1  280  30 15   8.7   4.7 | -28.4 -19.1  280  25 13   4.8   2.6
 18000 -27.1 -16.8  285  30 16   8.6   4.7 | -27.4 -17.3  280  23 12   8.8   4.8
 17500 -25.9 -14.6  280  30 15   8.6   4.7 | -26.1 -15.0  285  22 12   8.6   4.7
 17000 -24.6 -12.3  280  30 15   8.4   4.6 | -24.8 -12.6  285  22 11   8.3   4.6
 16500 -23.4 -10.1  285  29 15   8.1   4.5 | -23.6 -10.5  285  21 11   8.2   4.5
 16000 -22.2  -8.0  285  28 14   8.0   4.4 | -22.4  -8.3  290  21 11   8.1   4.4
 15500 -21.1  -6.0  285  27 14   6.5   3.6 | -21.3  -6.3  295  20 10   7.8   4.3
 15000 -20.2  -4.4  290  26 13   6.6   3.6 | -20.1  -4.2  295  20 10   7.8   4.3
 14500 -19.1  -2.4  295  25 13   7.4   4.1 | -18.9  -2.0  300  20 10   7.8   4.3
 14000 -17.5   0.5  300  24 13   7.5   4.1 | -17.8  -0.0  305  19 10   7.8   4.3
 13500 -16.4   2.5  300  24 12   7.8   4.3 | -16.6   2.1  310  20 10   8.2   4.5
 13000 -15.2   4.6  300  24 12   7.9   4.3 | -14.8   5.4  310  20 10   8.2   4.5
 12500 -14.0   6.8  300  23 12   8.3   4.5 | -13.5   7.7  310  20 10   8.2   4.5
 12000 -12.8   9.0  295  22 11   8.2   4.5 | -12.3   9.9  315  20 10   8.2   4.5
 11500 -11.6  11.1  290  22 11   7.9   4.3 | -11.1  12.0  310  20 10   8.2   4.5
 11000 -10.4  13.3  290  22 11   7.9   4.3 |  -9.9  14.2  310  20 10   8.5   4.7
 10500  -9.2  15.4  285  21 11   7.2   4.0 |  -8.6  16.5  310  20 10   9.6   5.3
 10250  -8.6  16.5  285  21 11  10.6   5.8 |  -8.0  17.6  305  20 11   5.2   2.8
 10000  -7.7  18.1  285  21 11  11.0   6.1 |  -7.7  18.1  305  20 11   5.9   3.2
  9750  -7.1  19.2  280  20 10   8.0   4.4 |  -7.0  19.4  305  20 10  10.8   5.9
  9500  -6.4  20.5  280  20 10   8.8   4.9 |  -6.3  20.7  305  20 10   9.7   5.3
  9250  -5.8  21.6  280  19 10   8.7   4.7 |  -5.5  22.1  300  20 10   9.1   5.0
  9000  -5.1  22.8  280  19 10   9.2   5.0 |  -4.9  23.2  300  20 10   8.3   4.5
  8750  -4.4  24.1  275  19 10   9.6   5.2 |  -4.3  24.3  300  20 10   9.1   5.0
  8500  -3.7  25.3  275  18  9   9.4   5.2 |  -3.6  25.5  300  20 10   9.1   5.0
  8250  -3.0  26.6  275  18  9  10.0   5.5 |  -2.9  26.8  295  20 10   9.8   5.4
  8000  -2.2  28.0  275  18  9  10.2   5.6 |  -2.1  28.2  295  20 10  10.3   5.6
  7750  -1.5  29.3  275  18  9   9.0   4.9 |  -1.4  29.5  295  20 10   9.4   5.2
  7500  -0.9  30.4  275  17  9   8.8   4.8 |  -0.7  30.7  295  20 10   9.5   5.2
  7250  -0.2  31.6  275  17  9   9.9   5.5 |   0.1  32.2  295  20 10  10.2   5.6
  7000   0.6  33.1  275  17  9  10.5   5.8 |   0.8  33.4  290  19 10  10.2   5.6
  6750   1.4  34.5  275  17  9   9.9   5.5 |   1.6  34.9  290  19 10   9.4   5.2
  6500   2.1  35.8  275  17  9  10.5   5.8 |   2.3  36.1  290  19 10  10.2   5.6
  6250   2.9  37.2  270  16  8  11.4   6.2 |   3.1  37.6  290  18  9  11.5   6.3
  6000   3.8  38.8  270  16  8  10.9   6.0 |   3.9  39.0  290  18  9  10.3   5.7
  5750   4.6  40.3  270  15  8  11.0   6.1 |   4.7  40.5  290  17  9  10.2   5.6
  5500   5.4  41.7  270  14  7  12.0   6.6 |   5.5  41.9  290  16  8  11.5   6.3
  5250   6.4  43.5  275  14  7  12.5   6.9 |   6.3  43.3  290  16  8  11.1   6.1
  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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