Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 181236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0536 MST Saturday, November 18, 2017

This forecast is for Saturday, November 18, 2017:

If the trigger temperature of 38.6 F/3.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 622 ft/min (3.2 m/s)
   Maximum height of thermals.................. 12933 ft MSL (8094 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11266 ft MSL (6427 ft AGL)
Thermal soaring outlook for Sunday 11/19....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:01:03 / 16:57:39 MST
Total possible sunshine........... 9 hr 56 min 36 sec (596 min 36 sec)
Altitude of sun at 11:59:32 MST... 31.53 degrees

Upper air data from rawinsonde observation taken on 11/18/2017 at 0500 MST

Freezing level.................. 5046 ft MSL (207 ft AGL)
Additional freezing level....... 5777 ft MSL (938 ft AGL)
Convective condensation level... 20487 ft MSL (15648 ft AGL)
Lifted condensation level....... 14523 ft MSL (9684 ft AGL)
Lifted index.................... +12.8
K index......................... -33.0

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  -62.2 -80.0   270   55   28   6.0   3.3   99.5 211.2    51.6      M    M
 45000  -54.1 -65.4   280   65   34   5.7   3.1   87.0 188.6    47.9      M    M
 40000  -50.1 -58.2   280   89   46   8.3   4.5   70.0 158.1    40.1      M    M
 38000  -52.3 -62.1   280   90   46   4.7   2.6   57.9 136.3    33.1      M    M
 36000  -50.5 -58.9   285   81   42  -2.6  -1.4   51.8 125.2    29.8      M    M
 34000  -53.2 -63.8   295   74   38  -3.6  -2.0   39.5 103.0    21.9      M    M
 32000  -50.3 -58.5   300   70   36   7.5   4.1   34.1  93.4    18.7      M    M
 30000  -45.8 -50.4   305   67   34   7.9   4.3   32.5  90.5    18.0      M    M
 29000  -43.4 -46.1   305   64   33   7.8   4.3   31.7  89.0    17.6      M    M
 28000  -41.1 -42.0   310   62   32   8.2   4.5   31.0  87.7    17.3      M    M
 27000  -38.4 -37.1   310   60   31   9.1   5.0   30.6  87.1    17.2      M    M
 26000  -35.9 -32.6   315   58   30   4.4   2.4   30.1  86.1    17.0      M    M
 25000  -34.3 -29.7   315   56   29   8.7   4.8   28.4  83.1    15.9      M    M
 24000  -31.8 -25.2   320   54   28   8.5   4.6   27.9  82.3    15.7      M    M
 23000  -29.4 -20.9   320   52   27   7.9   4.3   27.1  80.9    15.3      M    M
 22000  -27.0 -16.6   325   50   26   7.9   4.3   26.4  79.5    14.8      M    M
 21000  -24.7 -12.5   325   49   25   7.9   4.3   25.8  78.4    14.5      M    M
 20000  -22.3  -8.1   330   47   24   7.9   4.3   25.2  77.4    14.2      M    M
 19500  -21.1  -6.0   330   47   24   7.2   3.9   24.9  76.8    14.0      M    M
 19000  -20.1  -4.2   330   46   24   6.9   3.8   24.3  75.8    13.6      M    M
 18500  -19.1  -2.4   330   46   24   6.9   3.8   23.9  74.9    13.3      M    M
 18000  -17.5   0.5   330   45   23   7.0   3.8   23.1  73.5    12.7      M    M
 17500  -16.5   2.3   330   45   23   7.0   3.8   22.6  72.6    12.4      M    M
 17000  -15.4   4.3   335   45   23   7.0   3.8   22.1  71.8    12.0      M    M
 16500  -14.4   6.1   335   44   23   7.2   3.9   21.7  71.0    11.7      M    M
 16000  -13.5   7.7   335   44   23   1.9   1.0   21.0  69.8    11.2      M    M
 15500  -13.5   7.7   340   44   23   0.7   0.4   19.4  66.9     9.8      M    M
 15000  -12.8   9.0   340   44   22   7.9   4.3   18.5  65.4     9.1      M    M
 14500  -11.7  10.9   345   41   21   7.1   3.9   18.1  64.6     8.8      M    M
 14000  -11.2  11.8   345   37   19   2.0   1.1   17.1  62.7     7.9      M    M
 13500  -12.7   9.1   345   33   17 -26.6 -14.6   13.8  56.9     5.0      M    M
 13000  -16.1   3.0   345   28   15  -9.2  -5.1    8.4  47.2     0.1      M    M
 12500  -15.9   3.4   360   23   12   4.6   2.5    7.1  44.7    -1.2    602  3.1
 12000  -15.2   4.6   015   19   10   4.3   2.4    6.2  43.2    -2.0    568  2.9
 11500  -14.6   5.7   015   18    9   6.3   3.5    5.4  41.7    -2.8    534  2.7
 11000  -13.5   7.7   015   16    8   7.3   4.0    5.0  41.0    -3.2    485  2.5
 10500  -12.7   9.1   020   15    8   5.9   3.2    4.3  39.7    -3.9    448  2.3
 10250  -12.1  10.2   020   14    7   9.4   5.1    4.2  39.5    -4.1    423  2.1
 10000  -11.5  11.3   020   14    7   8.9   4.9    4.1  39.4    -4.1    395  2.0
  9750  -10.8  12.6   020   13    7   9.0   4.9    4.1  39.3    -4.2    368  1.9
  9500  -10.1  13.8   025   12    6   8.9   4.9    4.0  39.2    -4.3    340  1.7
  9250   -9.5  14.9   025   12    6   9.0   4.9    4.0  39.1    -4.3    313  1.6
  9000   -8.8  16.2   025   11    6   9.0   4.9    3.9  39.1    -4.4    286  1.5
  8750   -8.1  17.4   020   11    6   9.0   4.9    3.9  38.9    -4.5    258  1.3
  8500   -7.5  18.5   020   11    6   9.0   4.9    3.8  38.8    -4.5    231  1.2
  8250   -6.8  19.8   015   11    6   9.0   4.9    3.7  38.7    -4.6    203  1.0
  8000   -6.1  21.0   010   11    6   9.0   4.9    3.7  38.7    -4.7    176  0.9
  7750   -5.5  22.1   010   11    6   9.0   4.9    3.6  38.5    -4.8    149  0.8
  7500   -4.8  23.4   005   11    6   9.0   4.9    3.6  38.4    -4.8    121  0.6
  7250   -4.1  24.6   005   12    6   9.0   4.9    3.5  38.3    -4.9     94  0.5
  7000   -3.5  25.7   360   12    6   9.0   4.9    3.4  38.2    -5.0     67  0.3
  6750   -2.8  27.0   360   11    6   9.0   4.9    3.4  38.1    -5.1     39  0.2
  6500   -2.1  28.2   355   10    5   8.9   4.9    3.3  37.9    -5.2     12  0.1
  6250   -1.5  29.3   355    9    5   9.0   5.0    3.2  37.8    -5.3      M    M
  6000   -0.8  30.6   350    8    4   8.7   4.8    3.2  37.7    -5.3      M    M
  5750   -0.1  31.8   355    8    4   9.9   5.4    3.1  37.6    -5.4      M    M
  5500    0.5  32.9   355    7    4   5.5   3.0    3.0  37.4    -5.5      M    M
  5250    0.6  33.1   360    6    3  -1.7  -0.9    2.4  36.2    -6.2      M    M
  5000    0.3  32.5   355    6    3  -7.3  -4.0    1.3  34.4    -7.3      M    M

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

           11/18/2017 at 0800 MST          |       11/18/2017 at 1100 MST
                                           |
K index... -23.6  LI... +13.1              | K index... -20.1  LI... +9.2
CAPE... 0.0  CIN... 0.0                    | 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 -62.0 -79.6  285  61 32   3.8   2.1 | -61.0 -77.8  290  62 32   3.6   2.0
 45000 -56.0 -68.8  285  66 34   2.6   1.4 | -55.8 -68.4  290  66 34   1.6   0.9
 40000 -52.7 -62.9  290  73 38   2.2   1.2 | -54.4 -65.9  300  65 33   0.9   0.5
 38000 -52.4 -62.3  295  73 37  -1.4  -0.8 | -53.9 -65.0  305  63 32   0.4   0.2
 36000 -53.2 -63.8  295  68 35  -1.4  -0.8 | -53.7 -64.7  310  60 31   0.4   0.2
 34000 -53.8 -64.8  300  64 33   4.1   2.2 | -52.8 -63.0  320  58 30   5.3   2.9
 32000 -50.4 -58.7  300  61 31   5.0   2.8 | -49.6 -57.3  325  57 29   5.3   2.9
 30000 -47.0 -52.6  300  58 30   8.3   4.5 | -46.1 -51.0  325  55 28   7.4   4.1
 29000 -44.5 -48.1  305  56 29   8.3   4.6 | -43.9 -47.0  325  53 27   7.5   4.1
 28000 -42.0 -43.6  305  53 27   8.3   4.6 | -41.6 -42.9  325  51 26   7.5   4.1
 27000 -39.5 -39.1  305  51 26   8.4   4.6 | -39.4 -38.9  325  49 25   7.6   4.2
 26000 -37.0 -34.6  310  50 26   8.5   4.7 | -37.1 -34.8  320  48 25   7.8   4.3
 25000 -34.4 -29.9  310  48 25   8.5   4.7 | -34.7 -30.5  320  46 24   7.8   4.3
 24000 -31.9 -25.4  315  46 24   8.3   4.6 | -32.4 -26.3  320  45 23   7.9   4.3
 23000 -29.6 -21.3  315  45 23   7.6   4.2 | -30.0 -22.0  320  43 22   8.0   4.4
 22000 -27.3 -17.1  320  43 22   7.6   4.2 | -27.6 -17.7  320  42 21   8.1   4.4
 21000 -25.0 -13.0  320  41 21   7.5   4.1 | -25.2 -13.4  315  40 21   8.0   4.4
 20000 -22.8  -9.0  320  39 20   7.4   4.1 | -22.2  -8.0  320  38 20   8.0   4.4
 19500 -21.7  -7.1  325  39 20   7.4   4.1 | -21.0  -5.8  320  37 19   8.0   4.4
 19000 -20.0  -4.0  325  38 19   7.5   4.1 | -19.8  -3.6  320  36 19   8.0   4.4
 18500 -18.9  -2.0  325  37 19   6.7   3.7 | -18.7  -1.7  320  36 18   7.1   3.9
 18000 -17.9  -0.2  325  36 19   6.8   3.7 | -17.6   0.3  320  34 18   7.2   3.9
 17500 -16.9   1.6  330  35 18   7.2   4.0 | -16.6   2.1  320  33 17   7.0   3.8
 17000 -15.8   3.6  330  34 18   7.5   4.1 | -15.5   4.1  320  32 16   6.9   3.8
 16500 -14.7   5.5  330  33 17   7.6   4.2 | -14.5   5.9  325  31 16   6.9   3.8
 16000 -13.5   7.7  330  32 16   8.2   4.5 | -13.5   7.7  325  30 15   7.0   3.8
 15500 -12.2  10.0  330  31 16   8.3   4.6 | -12.4   9.7  325  29 15   7.0   3.8
 15000 -11.1  12.0  330  30 15   6.8   3.7 | -11.3  11.7  325  27 14   7.8   4.3
 14500 -10.1  13.8  335  29 15   7.1   3.9 | -10.1  13.8  325  26 13   7.8   4.3
 14000  -9.2  15.4  335  29 15   4.0   2.2 |  -9.0  15.8  325  25 13   7.2   4.0
 13500  -8.6  16.5  335  28 15   3.7   2.0 |  -7.9  17.8  330  24 12   7.4   4.1
 13000  -8.2  17.2  340  28 14  -0.5  -0.2 |  -7.0  19.4  330  23 12   4.7   2.6
 12500  -8.5  16.7  340  27 14  -1.7  -1.0 |  -6.3  20.7  330  22 11   4.6   2.5
 12000  -9.0  15.8  345  25 13  -6.3  -3.5 |  -5.8  21.6  335  21 11   0.4   0.2
 11500 -10.2  13.6  350  20 10  -8.3  -4.5 |  -5.9  21.4  335  19 10  -0.1  -0.1
 11000 -11.2  11.8  355  15  7  -1.2  -0.7 |  -6.1  21.0  335  17  9  -3.3  -1.8
 10500 -11.1  12.0  005  10  5   0.5   0.3 |  -6.7  19.9  340  13  7  -3.8  -2.1
 10250 -11.1  12.0  015   8  4   1.8   1.0 |  -7.0  19.4  345  12  6  -3.6  -2.0
 10000 -10.9  12.4  025   7  4   3.4   1.9 |  -7.3  18.9  355  10  5  -3.3  -1.8
  9750 -10.6  12.9  035   7  4   5.7   3.1 |  -7.5  18.5  005   8  4  -2.8  -1.5
  9500 -10.1  13.8  045   7  4   7.3   4.0 |  -7.7  18.1  015   6  3  -2.8  -1.5
  9250  -9.6  14.7  050   7  4   6.5   3.6 |  -7.9  17.8  030   5  3   0.8   0.4
  9000  -9.1  15.6  050   8  4   5.7   3.1 |  -7.7  18.1  045   5  3   3.3   1.8
  8750  -8.7  16.3  055   8  4   7.4   4.1 |  -7.5  18.5  055   5  2   3.9   2.2
  8500  -8.1  17.4  060   8  4   8.3   4.5 |  -7.1  19.2  070   5  3   5.7   3.1
  8250  -7.5  18.5  060   8  4   6.7   3.7 |  -6.7  19.9  075   5  3   5.6   3.1
  8000  -7.1  19.2  065   7  4   6.0   3.3 |  -6.3  20.7  080   5  2   5.4   3.0
  7750  -6.6  20.1  065   7  4   7.6   4.2 |  -5.8  21.6  085   5  2   6.4   3.5
  7500  -6.0  21.2  070   7  3   7.4   4.0 |  -5.3  22.5  090   4  2   7.7   4.2
  7250  -5.6  21.9  075   6  3   5.7   3.2 |  -4.8  23.4  095   3  2   7.8   4.3
  7000  -5.1  22.8  085   6  3   6.2   3.4 |  -4.2  24.4  100   3  1   7.5   4.1
  6750  -4.7  23.5  095   5  3   6.0   3.3 |  -3.7  25.3  110   2  1   8.7   4.7
  6500  -4.2  24.4  095   5  2   5.1   2.8 |  -2.9  26.8  115   2  1  10.3   5.7
  6250  -3.9  25.0  100   4  2   4.6   2.5 |  -2.1  28.2  115   2  1  10.5   5.7
  6000  -3.5  25.7  110   4  2   4.4   2.4 |  -1.4  29.5  120   2  1  10.3   5.6
  5750  -3.3  26.1  105   4  2   1.8   1.0 |  -0.5  31.1  125   2  1  14.7   8.0
  5500  -3.3  26.1  100   4  2  -1.5  -0.8 |   0.9  33.6  125   2  1  22.4  12.3
  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

           11/18/2017 at 1400 MST          |       11/18/2017 at 1700 MST
                                           |
K index... -22.6  LI... +8.0               | K index... -21.1  LI... +7.9
CAPE... 0.0  CIN... 0.0                    | 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 -61.0 -77.8  290  62 32   2.7   1.5 | -62.1 -79.8  295  64 33   3.2   1.8
 45000 -57.1 -70.8  290  70 36   0.7   0.4 | -57.3 -71.1  295  71 36  -0.9  -0.5
 40000 -57.2 -71.0  305  67 35  -0.1  -0.0 | -59.7 -75.5  300  67 34  -1.6  -0.9
 38000 -56.4 -69.5  310  67 35   2.6   1.4 | -58.6 -73.5  305  66 34   4.8   2.6
 36000 -54.9 -66.8  320  68 35   2.6   1.4 | -55.7 -68.3  310  65 34   4.8   2.7
 34000 -52.6 -62.7  325  68 35   6.2   3.4 | -52.0 -61.6  310  64 33   7.4   4.1
 32000 -48.8 -55.8  325  64 33   6.3   3.5 | -47.5 -53.5  315  62 32   7.4   4.1
 30000 -44.8 -48.6  320  61 31   7.3   4.0 | -43.2 -45.8  315  59 31   6.7   3.7
 29000 -42.6 -44.7  320  59 30   7.3   4.0 | -41.2 -42.2  315  58 30   6.7   3.7
 28000 -40.4 -40.7  320  56 29   7.3   4.0 | -39.2 -38.6  315  57 29   6.7   3.7
 27000 -38.2 -36.8  320  54 28   7.5   4.1 | -37.1 -34.8  315  55 28   7.3   4.0
 26000 -36.0 -32.8  320  53 27   7.5   4.1 | -34.9 -30.8  315  53 27   7.4   4.0
 25000 -33.7 -28.7  320  51 26   7.5   4.1 | -32.7 -26.9  310  50 26   7.4   4.0
 24000 -31.5 -24.7  320  50 26   7.9   4.3 | -30.5 -22.9  310  48 25   7.5   4.1
 23000 -29.0 -20.2  320  47 24   8.3   4.5 | -28.2 -18.8  310  45 23   7.6   4.2
 22000 -26.5 -15.7  325  44 23   8.3   4.6 | -26.0 -14.8  310  43 22   7.6   4.2
 21000 -24.1 -11.4  325  41 21   7.7   4.2 | -23.7 -10.7  310  41 21   7.6   4.2
 20000 -21.2  -6.2  325  39 20   7.7   4.2 | -21.4  -6.5  310  38 20   7.6   4.2
 19500 -20.0  -4.0  320  37 19   7.7   4.2 | -19.7  -3.5  315  37 19   7.6   4.2
 19000 -18.9  -2.0  320  36 19   7.7   4.2 | -18.6  -1.5  315  36 18   7.7   4.2
 18500 -17.7   0.1  320  35 18   7.4   4.0 | -17.4   0.7  315  34 18   7.9   4.3
 18000 -16.6   2.1  320  34 18   7.4   4.1 | -16.2   2.8  315  33 17   8.0   4.4
 17500 -15.5   4.1  320  33 17   7.3   4.0 | -15.1   4.8  315  31 16   6.7   3.7
 17000 -14.4   6.1  325  32 16   7.2   4.0 | -14.1   6.6  315  30 15   6.6   3.6
 16500 -13.4   7.9  325  31 16   7.1   3.9 | -13.1   8.4  320  28 14   6.5   3.5
 16000 -12.3   9.9  325  29 15   6.8   3.7 | -12.2  10.0  320  26 13   6.3   3.5
 15500 -11.3  11.7  325  28 14   6.8   3.7 | -11.2  11.8  320  24 12   6.3   3.5
 15000 -10.4  13.3  325  26 13   5.8   3.2 | -10.3  13.5  320  23 12   6.3   3.4
 14500  -9.5  14.9  325  24 13   5.7   3.1 |  -9.4  15.1  325  21 11   6.3   3.4
 14000  -8.6  16.5  325  23 12   7.1   3.9 |  -8.5  16.7  325  19 10   6.3   3.4
 13500  -7.5  18.5  325  21 11   7.1   3.9 |  -7.5  18.5  325  18  9   6.3   3.4
 13000  -6.6  20.1  325  19 10   5.9   3.2 |  -6.6  20.1  320  16  8   6.4   3.5
 12500  -5.7  21.7  325  17  9   5.9   3.2 |  -5.6  21.9  320  15  7   6.5   3.6
 12000  -4.9  23.2  325  16  8   3.8   2.1 |  -4.8  23.4  320  13  7   4.3   2.4
 11500  -4.4  24.1  325  14  7   3.8   2.1 |  -4.2  24.4  315  12  6   4.5   2.4
 11000  -4.1  24.6  325  13  7  -0.6  -0.3 |  -3.7  25.3  315  10  5   1.1   0.6
 10500  -4.2  24.4  320  11  6  -1.1  -0.6 |  -3.5  25.7  305   9  4   1.1   0.6
 10250  -4.3  24.3  320  10  5  -1.0  -0.5 |  -3.5  25.7  305   8  4   0.6   0.3
 10000  -4.4  24.1  320   9  4  -0.8  -0.4 |  -3.4  25.9  300   7  4   0.1   0.1
  9750  -4.5  23.9  320   7  4  -0.9  -0.5 |  -3.4  25.9  295   6  3   0.5   0.3
  9500  -4.5  23.9  325   6  3  -1.1  -0.6 |  -3.4  25.9  290   5  3   0.6   0.3
  9250  -4.6  23.7  335   4  2   0.1   0.0 |  -3.3  26.1  280   4  2   2.0   1.1
  9000  -4.6  23.7  345   3  1   1.0   0.5 |  -3.1  26.4  275   4  2   3.1   1.7
  8750  -4.5  23.9  015   1  1   1.6   0.9 |  -2.9  26.8  270   3  1   3.8   2.1
  8500  -4.3  24.3  095   1  1   3.1   1.7 |  -2.5  27.5  260   2  1   4.9   2.7
  8250  -4.1  24.6  120   2  1   4.2   2.3 |  -2.2  28.0  240   1  1   4.9   2.7
  8000  -3.8  25.2  125   2  1   4.2   2.3 |  -1.8  28.8  220   1  1   4.9   2.7
  7750  -3.4  25.9  135   2  1   5.9   3.2 |  -1.4  29.5  205   1  1   5.5   3.0
  7500  -2.9  26.8  155   2  1   7.8   4.3 |  -1.0  30.2  200   1  1   5.2   2.9
  7250  -2.3  27.9  160   1  1   7.5   4.1 |  -0.7  30.7  175   1  1   4.4   2.4
  7000  -1.8  28.8  170   1  1   7.3   4.0 |  -0.4  31.3  160   1  1   4.6   2.5
  6750  -1.3  29.7  175   1  1   8.6   4.7 |  -0.0  32.0  145   2  1   4.7   2.6
  6500  -0.6  30.9  185   1  1  10.4   5.7 |   0.4  32.7  145   2  1   6.4   3.5
  6250   0.2  32.4  190   1  1  10.7   5.9 |   0.9  33.6  155   1  1   7.1   3.9
  6000   1.0  33.8  195   1  1  10.1   5.5 |   1.4  34.5  165   1  1   7.6   4.2
  5750   1.9  35.4  200   1  1  13.9   7.6 |   1.9  35.4  185   1  0   7.1   3.9
  5500   3.2  37.8  200   1  1  21.9  12.0 |   2.3  36.1  190   1  0   4.1   2.2
  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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