Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231240
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0540 MST Friday, February 23, 2018

This forecast is for Friday, February 23, 2018:

If the trigger temperature of 36.5 F/2.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 194 ft/min (1.0 m/s)
   Maximum height of thermals.................. 11916 ft MSL (7090 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1045 MST
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................. 5806 ft MSL (980 ft AGL)
Thermal soaring outlook for Saturday 02/24..... Poor

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

Remarks...

Sunrise/Sunset.................... 06:54:55 / 17:59:11 MST
Total possible sunshine........... 11 hr 4 min 16 sec (664 min 16 sec)
Altitude of sun at 12:27:19 MST... 41.28 degrees

Upper air data from rawinsonde observation taken on 02/23/2018 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10310 ft MSL (5484 ft AGL)
Lifted condensation level....... 10511 ft MSL (5685 ft AGL)
Lifted index.................... +6.9
K index......................... +7.8

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  -56.2 -69.2   230   72   37   2.0   1.1  113.0 235.4    61.3      M    M
 45000  -53.4 -64.1   235   94   48   4.2   2.3   92.8 199.0    53.4      M    M
 40000  -53.5 -64.3   225   88   45  -4.3  -2.3   67.9 154.3    41.3      M    M
 38000  -53.1 -63.6   225   72   37   2.7   1.5   59.6 139.2    36.8      M    M
 36000  -52.5 -62.5   235   81   42   5.5   3.0   51.6 124.9    32.4      M    M
 34000  -52.2 -62.0   240  107   55   0.4   0.2   43.7 110.6    27.7      M    M
 32000  -50.5 -58.9   235  108   56   4.7   2.6   37.9 100.2    24.3      M    M
 30000  -51.2 -60.2   225  113   58  -4.6  -2.5   28.9  84.0    18.4      M    M
 29000  -49.7 -57.5   230  115   59  -0.4  -0.2   26.0  78.8    16.5      M    M
 28000  -48.8 -55.8   230  119   61   5.7   3.1   23.3  73.9    14.7      M    M
 27000  -47.1 -52.8   230  115   59   5.8   3.2   21.7  71.0    13.6      M    M
 26000  -45.1 -49.2   225  111   57   7.3   4.0   20.5  68.9    12.9      M    M
 25000  -42.9 -45.2   225  107   55   7.4   4.0   19.7  67.4    12.4      M    M
 24000  -40.7 -41.3   225  104   53   7.4   4.0   18.7  65.6    11.8      M    M
 23000  -38.5 -37.3   230  102   52   5.4   3.0   17.8  64.1    11.2      M    M
 22000  -37.4 -35.3   230   83   43   1.8   1.0   15.6  60.0     9.5      M    M
 21000  -38.3 -36.9   230   64   33   0.3   0.2   11.0  51.7     5.8      M    M
 20000  -37.9 -36.2   230   45   23   4.9   2.7    8.0  46.4     3.4      M    M
 19500  -37.2 -35.0   230   39   20   5.8   3.2    7.1  44.7     2.7      M    M
 19000  -36.0 -32.8   225   34   17   8.9   4.9    6.8  44.3     2.4      M    M
 18500  -34.7 -30.5   225   32   16   8.8   4.8    6.6  43.9     2.3      M    M
 18000  -33.4 -28.1   225   30   16   8.8   4.8    6.5  43.7     2.2      M    M
 17500  -32.1 -25.8   225   29   15   8.6   4.7    6.3  43.3     2.0      M    M
 17000  -30.8 -23.4   220   27   14   8.6   4.7    6.1  42.9     1.8      M    M
 16500  -29.5 -21.1   220   26   13   8.6   4.7    5.9  42.6     1.7      M    M
 16000  -28.2 -18.8   215   24   13   8.6   4.7    5.7  42.3     1.5      M    M
 15500  -26.3 -15.3   215   23   12   8.6   4.7    5.4  41.7     1.3      M    M
 15000  -25.0 -13.0   215   22   12   8.4   4.6    5.2  41.4     1.1      M    M
 14500  -23.8 -10.8   215   22   11   8.2   4.5    4.9  40.9     0.9      M    M
 14000  -22.6  -8.7   215   21   11   8.2   4.5    4.7  40.5     0.6      M    M
 13500  -21.4  -6.5   215   22   11   8.2   4.5    4.4  40.0     0.4      M    M
 13000  -20.2  -4.4   220   22   11   8.5   4.7    4.2  39.5     0.1      M    M
 12500  -18.8  -1.8   220   23   12   9.6   5.3    4.1  39.4     0.0      M    M
 12000  -17.4   0.7   220   23   12   9.5   5.2    4.1  39.3     0.0      M    M
 11500  -16.0   3.2   215   23   12   9.5   5.2    4.0  39.2    -0.1    540  2.7
 11000  -14.5   5.9   215   24   12   8.9   4.9    4.0  39.2    -0.1    483  2.5
 10500  -13.3   8.1   215   24   13   8.3   4.6    3.7  38.7    -0.3    432  2.2
 10250  -12.7   9.1   210   25   13   8.3   4.6    3.6  38.5    -0.5    406  2.1
 10000  -12.1  10.2   210   25   13   8.2   4.5    3.5  38.3    -0.6    380  1.9
  9750  -11.5  11.3   210   25   13   7.5   4.1    3.4  38.1    -0.7    356  1.8
  9500  -11.0  12.2   210   24   12   6.8   3.8    3.2  37.7    -0.9    333  1.7
  9250  -10.5  13.1   205   23   12   7.9   4.3    3.0  37.3    -1.2    310  1.6
  9000   -9.9  14.2   205   22   11   8.7   4.8    2.9  37.2    -1.2    283  1.4
  8750   -9.2  15.4   200   21   11   8.5   4.7    2.8  37.0    -1.3    257  1.3
  8500   -8.6  16.5   190   19   10   8.6   4.7    2.7  36.8    -1.4    231  1.2
  8250   -8.0  17.6   185   19   10   8.6   4.7    2.6  36.7    -1.5    204  1.0
  8000   -7.3  18.9   175   18    9   8.6   4.7    2.5  36.6    -1.6    178  0.9
  7750   -6.7  19.9   170   18    9   8.6   4.7    2.4  36.4    -1.7    152  0.8
  7500   -6.1  21.0   170   18    9   8.6   4.7    2.3  36.2    -1.8    125  0.6
  7250   -5.4  22.3   165   19   10   8.6   4.7    2.3  36.1    -1.9     99  0.5
  7000   -4.8  23.4   160   19   10   8.6   4.7    2.2  35.9    -2.0     73  0.4
  6750   -4.2  24.4   160   19   10   8.6   4.7    2.1  35.7    -2.1     46  0.2
  6500   -3.5  25.7   155   19   10   8.4   4.6    2.0  35.5    -2.3     20  0.1
  6250   -2.9  26.8   155   19   10   9.2   5.1    1.9  35.4    -2.4      M    M
  6000   -2.3  27.9   150   19   10   6.1   3.3    1.8  35.2    -2.5      M    M
  5750   -2.1  28.2   150   17    9   1.4   0.8    1.3  34.3    -3.0      M    M
  5500   -2.0  28.4   145   15    8   0.9   0.5    0.6  33.1    -3.7      M    M
  5250   -1.9  28.6   140   12    6   1.6   0.9   -0.0  31.9    -4.3      M    M
  5000   -1.8  28.8   130   10    5   3.5   1.9   -0.6  31.0    -4.9      M    M

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

           02/23/2018 at 0800 MST          |       02/23/2018 at 1100 MST
                                           |
K index... +12.2  LI... +0.5               | K index... +13.5  LI... +0.6
CAPE... +7.2  CIN... -10.8                 | CAPE... +4.9  CIN... -2.3
                                           |
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 -56.6 -69.9  240  79 41   2.4   1.3 | -57.0 -70.6  240  79 41   1.8   1.0
 45000 -53.0 -63.4  235  88 46   2.4   1.3 | -54.3 -65.7  240  85 44   1.8   1.0
 40000 -52.2 -62.0  240  85 44   0.0   0.0 | -52.9 -63.2  235  86 44   0.7   0.4
 38000 -52.2 -62.0  240  83 43   0.3   0.2 | -52.5 -62.5  235  86 44   0.9   0.5
 36000 -51.7 -61.1  235  92 47   1.0   0.5 | -51.8 -61.2  235  95 49   1.1   0.6
 34000 -51.1 -60.0  235 101 52   1.0   0.5 | -51.1 -60.0  230 104 54   1.1   0.6
 32000 -50.2 -58.4  235 108 56   1.7   0.9 | -50.1 -58.2  230 109 56   2.1   1.2
 30000 -49.2 -56.6  235 114 58   1.7   0.9 | -48.8 -55.8  230 111 57   2.1   1.2
 29000 -48.3 -54.9  230 115 59   3.9   2.1 | -48.1 -54.6  230 112 57   3.5   1.9
 28000 -47.2 -53.0  230 114 59   3.8   2.1 | -46.8 -52.2  230 109 56   3.6   2.0
 27000 -46.0 -50.8  230 112 58   3.8   2.1 | -45.7 -50.3  230 106 55   3.6   2.0
 26000 -44.9 -48.8  230 111 57   4.9   2.7 | -44.6 -48.3  230 104 53   4.2   2.3
 25000 -43.1 -45.6  230 106 55   5.8   3.2 | -43.2 -45.8  230  96 50   4.7   2.6
 24000 -41.4 -42.5  230 101 52   5.8   3.2 | -41.8 -43.2  230  89 46   4.7   2.6
 23000 -39.6 -39.3  230  96 50   4.4   2.4 | -40.4 -40.7  230  81 42   4.3   2.3
 22000 -38.8 -37.8  230  82 42   3.0   1.7 | -39.2 -38.6  225  69 36   3.9   2.2
 21000 -37.9 -36.2  230  68 35   3.0   1.7 | -38.0 -36.4  225  57 29   4.0   2.2
 20000 -36.6 -33.9  230  56 29   7.8   4.3 | -36.4 -33.5  225  46 24   8.8   4.9
 19500 -35.5 -31.9  230  51 26   7.4   4.1 | -35.1 -31.2  225  40 21   8.5   4.7
 19000 -34.4 -29.9  230  47 24   7.4   4.1 | -33.9 -29.0  225  35 18   8.5   4.7
 18500 -33.3 -27.9  230  43 22   7.4   4.1 | -32.6 -26.7  225  30 15   8.5   4.7
 18000 -32.1 -25.8  235  38 20   7.5   4.1 | -31.3 -24.3  220  24 12   8.6   4.7
 17500 -31.0 -23.8  235  35 18   8.1   4.4 | -30.0 -22.0  220  22 12   9.2   5.0
 17000 -29.8 -21.6  230  32 17   8.0   4.4 | -28.6 -19.5  220  22 11   9.3   5.1
 16500 -28.6 -19.5  230  30 16   8.3   4.5 | -27.3 -17.1  225  22 11   8.2   4.5
 16000 -27.3 -17.1  230  29 15   8.3   4.5 | -26.1 -15.0  225  24 12   8.3   4.5
 15500 -26.1 -15.0  225  28 15   8.2   4.5 | -24.9 -12.8  225  25 13   7.8   4.3
 15000 -24.9 -12.8  220  27 14   8.1   4.5 | -23.8 -10.8  225  25 13   7.6   4.2
 14500 -23.7 -10.7  215  27 14   7.8   4.3 | -22.6  -8.7  225  25 13   7.5   4.1
 14000 -22.0  -7.6  210  24 12   7.4   4.1 | -21.5  -6.7  225  25 13   7.4   4.1
 13500 -20.9  -5.6  205  22 11   7.7   4.2 | -19.9  -3.8  225  25 13   7.3   4.0
 13000 -19.8  -3.6  200  20 10   7.6   4.2 | -18.8  -1.8  225  26 13   7.3   4.0
 12500 -18.5  -1.3  200  19 10   9.1   5.0 | -17.7   0.1  225  27 14   7.6   4.2
 12000 -17.2   1.0  210  20 10   9.2   5.0 | -16.6   2.1  225  28 15   7.6   4.2
 11500 -15.9   3.4  215  20 10   8.3   4.6 | -15.5   4.1  225  30 15   7.6   4.2
 11000 -14.6   5.7  215  19 10   8.5   4.6 | -14.3   6.3  220  31 16   7.7   4.2
 10500 -13.5   7.7  215  17  9   7.8   4.3 | -13.3   8.1  220  32 17   6.8   3.8
 10250 -12.9   8.8  215  17  9   7.3   4.0 | -12.8   9.0  215  33 17   6.2   3.4
 10000 -12.3   9.9  210  16  8   9.4   5.2 | -12.3   9.9  215  33 17   9.0   4.9
  9750 -11.6  11.1  210  16  8   9.6   5.3 | -11.5  11.3  210  34 17   9.6   5.3
  9500 -11.0  12.2  210  15  8   7.6   4.2 | -10.9  12.4  210  33 17   7.2   4.0
  9250 -10.4  13.3  210  14  7   8.3   4.6 | -10.4  13.3  205  33 17   8.1   4.5
  9000  -9.8  14.4  205  13  7   7.7   4.2 |  -9.8  14.4  205  33 17   6.9   3.8
  8750  -9.2  15.4  205  12  6   7.9   4.3 |  -9.3  15.3  205  31 16   6.9   3.8
  8500  -8.6  16.5  200  13  6   8.5   4.7 |  -8.8  16.2  200  30 15   7.8   4.3
  8250  -8.0  17.6  200  13  7   8.3   4.5 |  -8.2  17.2  200  28 15   7.6   4.2
  8000  -7.4  18.7  200  13  7   7.4   4.1 |  -7.6  18.3  195  27 14   7.8   4.3
  7750  -6.9  19.6  195  14  7   6.2   3.4 |  -7.1  19.2  190  25 13   6.9   3.8
  7500  -6.4  20.5  195  15  8   6.1   3.3 |  -6.6  20.1  185  23 12   6.2   3.4
  7250  -6.0  21.2  190  16  8   5.9   3.2 |  -6.2  20.8  180  21 11   6.7   3.7
  7000  -5.6  21.9  185  15  8   5.5   3.0 |  -5.7  21.7  180  19 10   7.1   3.9
  6750  -5.2  22.6  175  15  8   5.7   3.1 |  -5.1  22.8  175  17  9   7.9   4.3
  6500  -4.8  23.4  170  14  7   5.0   2.7 |  -4.5  23.9  175  15  8   8.7   4.8
  6250  -4.5  23.9  160  14  7   3.3   1.8 |  -3.9  25.0  170  14  7   9.0   4.9
  6000  -4.3  24.3  155  12  6   2.8   1.5 |  -3.2  26.2  170  12  6   9.2   5.1
  5750  -4.1  24.6  150  11  5   2.6   1.4 |  -2.5  27.5  170  11  6   9.2   5.0
  5500  -3.9  25.0  140   9  4   3.1   1.7 |  -1.9  28.6  170   9  5   8.2   4.5
  5250  -3.6  25.5  140   8  4   4.4   2.4 |  -1.3  29.7  170   9  5   6.8   3.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/23/2018 at 1400 MST          |       02/23/2018 at 1700 MST
                                           |
K index... +13.7  LI... -0.3               | K index... +18.3  LI... +0.4
CAPE... +52.6  CIN... -4.3                 | CAPE... +14.8  CIN... -15.6
                                           |
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 -57.0 -70.6  240  77 40   1.7   0.9 | -56.3 -69.3  245  72 37   2.0   1.1
 45000 -54.5 -66.1  240  79 41   1.7   0.9 | -53.4 -64.1  240  71 37   2.0   1.1
 40000 -52.9 -63.2  235  78 40   0.8   0.4 | -51.8 -61.2  235  68 35   0.7   0.4
 38000 -52.5 -62.5  235  77 40   1.1   0.6 | -51.4 -60.5  235  67 34   0.8   0.5
 36000 -51.6 -60.9  230  87 45   1.5   0.8 | -50.7 -59.3  235  76 39   1.1   0.6
 34000 -50.6 -59.1  230  96 50   1.5   0.8 | -50.1 -58.2  230  85 44   1.1   0.6
 32000 -49.4 -56.9  230 102 52   2.4   1.3 | -49.2 -56.6  230  89 46   1.8   1.0
 30000 -48.0 -54.4  230 104 53   2.4   1.3 | -48.1 -54.6  230  88 45   1.8   1.0
 29000 -47.0 -52.6  230 104 54   3.4   1.9 | -47.4 -53.3  230  86 44   1.6   0.9
 28000 -46.0 -50.8  225 102 53   3.4   1.9 | -46.9 -52.4  230  81 42   1.7   0.9
 27000 -45.0 -49.0  225 101 52   3.4   1.9 | -46.4 -51.5  230  77 40   1.6   0.9
 26000 -43.9 -47.0  225  99 51   3.5   1.9 | -45.9 -50.6  230  73 38   1.4   0.8
 25000 -42.8 -45.0  225  92 47   3.7   2.0 | -45.7 -50.3  230  64 33   0.8   0.5
 24000 -41.7 -43.1  225  84 43   3.7   2.0 | -45.4 -49.7  230  55 28   0.9   0.5
 23000 -40.6 -41.1  230  77 40   3.7   2.0 | -45.2 -49.4  230  45 23   4.3   2.4
 22000 -39.5 -39.1  230  68 35   3.7   2.0 | -42.5 -44.5  230  39 20   9.2   5.0
 21000 -38.4 -37.1  230  58 30   3.7   2.0 | -39.7 -39.5  225  32 16   9.2   5.0
 20000 -36.9 -34.4  230  50 26   9.1   5.0 | -37.0 -34.6  225  27 14   9.4   5.2
 19500 -35.6 -32.1  225  46 24   8.6   4.7 | -35.6 -32.1  225  27 14   9.4   5.2
 19000 -34.4 -29.9  225  42 22   8.6   4.7 | -34.2 -29.6  225  26 14   9.4   5.2
 18500 -33.1 -27.6  225  38 20   8.6   4.7 | -32.8 -27.0  225  26 13   9.4   5.2
 18000 -31.8 -25.2  225  34 18   8.6   4.7 | -31.3 -24.3  225  26 13   9.3   5.1
 17500 -30.5 -22.9  220  33 17   8.9   4.9 | -30.1 -22.2  225  25 13   8.2   4.5
 17000 -29.2 -20.6  220  32 17   8.9   4.9 | -28.8 -19.8  225  24 12   8.3   4.5
 16500 -27.9 -18.2  220  32 16   8.5   4.7 | -27.6 -17.7  225  23 12   8.3   4.6
 16000 -26.6 -15.9  220  31 16   8.5   4.7 | -26.4 -15.5  225  23 12   8.3   4.6
 15500 -25.4 -13.7  215  30 16   8.0   4.4 | -25.1 -13.2  225  22 11   8.1   4.4
 15000 -24.2 -11.6  220  30 16   7.8   4.3 | -23.9 -11.0  230  21 11   8.0   4.4
 14500 -23.0  -9.4  225  31 16   7.6   4.2 | -22.8  -9.0  230  21 11   7.9   4.3
 14000 -21.9  -7.4  225  29 15   7.5   4.1 | -21.0  -5.8  230  19 10   7.7   4.3
 13500 -20.2  -4.4  225  26 14   8.2   4.5 | -19.9  -3.8  230  18  9   7.8   4.3
 13000 -19.0  -2.2  225  25 13   8.2   4.5 | -18.7  -1.7  235  18  9   7.8   4.3
 12500 -17.8  -0.0  225  22 12   7.6   4.2 | -17.6   0.3  235  17  9   8.0   4.4
 12000 -16.7   1.9  225  20 10   7.6   4.2 | -16.4   2.5  235  16  8   8.1   4.5
 11500 -15.6   3.9  220  18  9   8.0   4.4 | -15.2   4.6  235  16  8   7.4   4.1
 11000 -14.4   6.1  225  18  9   8.1   4.4 | -14.1   6.6  235  15  8   7.5   4.1
 10500 -13.3   8.1  220  19 10   7.4   4.0 | -13.1   8.4  235  14  7   6.9   3.8
 10250 -12.7   9.1  220  19 10   7.0   3.8 | -12.6   9.3  235  14  7   6.6   3.6
 10000 -12.2  10.0  220  20 10   8.8   4.8 | -12.1  10.2  235  14  7   8.1   4.4
  9750 -11.5  11.3  220  20 10   9.0   5.0 | -11.4  11.5  240  14  7   8.6   4.7
  9500 -10.9  12.4  220  20 10   7.3   4.0 | -10.9  12.4  240  13  7   7.4   4.0
  9250 -10.3  13.5  215  20 10   7.9   4.4 | -10.3  13.5  240  13  7   7.8   4.3
  9000  -9.8  14.4  215  20 10   7.2   3.9 |  -9.8  14.4  240  12  6   7.4   4.1
  8750  -9.3  15.3  215  19 10   7.5   4.1 |  -9.2  15.4  240  12  6   7.2   4.0
  8500  -8.7  16.3  215  19 10   8.4   4.6 |  -8.7  16.3  235  11  6   7.4   4.0
  8250  -8.1  17.4  210  18  9   8.2   4.5 |  -8.2  17.2  235  11  5   7.3   4.0
  8000  -7.4  18.7  210  17  9   8.9   4.9 |  -7.6  18.3  235  10  5   7.1   3.9
  7750  -6.8  19.8  205  17  9   8.8   4.8 |  -7.1  19.2  235   9  5   7.2   4.0
  7500  -6.2  20.8  205  16  8   8.1   4.5 |  -6.6  20.1  230   8  4   7.5   4.1
  7250  -5.6  21.9  205  15  8   8.7   4.8 |  -6.0  21.2  230   8  4   7.5   4.1
  7000  -4.9  23.2  205  14  7   9.2   5.1 |  -5.5  22.1  230   7  4   7.5   4.1
  6750  -4.2  24.4  205  13  7   9.3   5.1 |  -5.0  23.0  225   6  3   6.8   3.7
  6500  -3.5  25.7  205  12  6   9.6   5.3 |  -4.5  23.9  225   5  3   6.6   3.6
  6250  -2.8  27.0  205  12  6  10.5   5.7 |  -4.0  24.8  225   5  2   7.7   4.2
  6000  -2.0  28.4  205  11  6  10.8   5.9 |  -3.4  25.9  225   4  2   8.1   4.5
  5750  -1.2  29.8  205  10  5  10.0   5.5 |  -2.8  27.0  220   4  2   8.1   4.5
  5500  -0.5  31.1  205   9  5   8.5   4.7 |  -2.3  27.9  220   3  2   6.4   3.5
  5250   0.0  32.0  205   9  5   7.1   3.9 |  -1.9  28.6  225   3  2   3.4   1.9
  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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