Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221224
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0524 MST Sunday, January 22, 2017

This forecast is for Sunday, January 22, 2017:

If the trigger temperature of 38.5 F/3.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7145 ft MSL (2306 ft AGL)

Forecast maximum temperature................... 37.0 F/3.2 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5048 ft MSL (209 ft AGL)
Thermal soaring outlook for Monday 01/23....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:27:56 / 17:22:49 MST
Total possible sunshine........... 9 hr 54 min 52 sec (594 min 52 sec)
Altitude of sun at 12:25:46 MST... 31.45 degrees

Upper air data from rawinsonde observation taken on 01/22/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 11347 ft MSL (6508 ft AGL)
Lifted condensation level....... 10359 ft MSL (5520 ft AGL)
Lifted index.................... +13.7
K index......................... -10.6

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  -59.4 -74.9   280   33   17   7.5   4.1  102.2 216.0    56.6      M    M
 45000  -50.0 -58.0   285   87   45   2.0   1.1   93.5 200.4    55.2      M    M
 40000  -44.4 -47.9   295   72   37   6.9   3.8   78.9 174.0    49.5      M    M
 38000  -47.1 -52.8   295  103   53  -4.7  -2.6   64.9 148.9    41.6      M    M
 36000  -49.5 -57.1   305  139   72   5.5   3.0   52.7 126.8    34.2      M    M
 34000  -47.5 -53.5   305  149   77  -1.0  -0.5   47.1 116.8    31.2      M    M
 32000  -46.3 -51.3   300  161   83   5.8   3.2   40.6 105.0    27.3      M    M
 30000  -43.5 -46.3   300  140   72   7.4   4.1   36.4  97.6    25.0      M    M
 29000  -41.5 -42.7   300  131   67   6.4   3.5   35.1  95.2    24.3      M    M
 28000  -39.5 -39.1   300  122   63   6.7   3.7   33.8  92.9    23.6      M    M
 27000  -37.6 -35.7   305  114   59   5.4   3.0   32.6  90.7    23.0      M    M
 26000  -35.5 -31.9   305  105   54   8.2   4.5   31.5  88.7    22.4      M    M
 25000  -33.4 -28.1   300  100   52   6.3   3.4   30.4  86.7    21.8      M    M
 24000  -32.7 -26.9   300  106   54   1.0   0.6   27.7  81.8    19.9      M    M
 23000  -32.0 -25.6   300   97   50   5.3   2.9   24.8  76.7    17.8      M    M
 22000  -30.4 -22.7   305   89   46   7.7   4.2   23.3  73.9    16.7      M    M
 21000  -28.1 -18.6   305   81   42   8.0   4.4   22.5  72.5    16.3      M    M
 20000  -25.1 -13.2   310   70   36   8.5   4.6   21.8  71.2    16.0      M    M
 19500  -24.2 -11.6   310   64   33   0.2   0.1   21.1  70.0    15.5      M    M
 19000  -24.5 -12.1   310   57   29  -1.8  -1.0   19.0  66.1    13.8      M    M
 18500  -24.8 -12.6   310   50   26   1.4   0.8   16.9  62.4    12.1      M    M
 18000  -24.0 -11.2   310   47   24   5.5   3.0   16.2  61.1    11.5      M    M
 17500  -23.2  -9.8   305   46   23   5.3   2.9   15.3  59.6    10.9      M    M
 17000  -22.4  -8.3   300   44   23   5.2   2.9   14.6  58.2    10.3      M    M
 16500  -21.6  -6.9   300   44   22   5.0   2.8   13.8  56.8     9.7      M    M
 16000  -20.8  -5.4   295   43   22   2.3   1.2   13.1  55.5     9.1      M    M
 15500  -21.3  -6.3   295   39   20  -3.3  -1.8   10.9  51.6     7.2      M    M
 15000  -20.8  -5.4   295   35   18   7.4   4.0    9.8  49.6     6.2      M    M
 14500  -19.8  -3.6   290   31   16   6.6   3.6    9.3  48.7     5.8      M    M
 14000  -18.7  -1.7   290   28   14   8.2   4.5    8.9  48.0     5.4      M    M
 13500  -17.5   0.5   290   26   13   8.5   4.7    8.6  47.5     5.2      M    M
 13000  -16.5   2.3   290   24   12   4.6   2.5    8.1  46.5     4.7      M    M
 12500  -15.9   3.4   295   22   11  -0.2  -0.1    7.2  44.9     3.9      M    M
 12000  -15.6   3.9   295   20   10   8.2   4.5    6.0  42.7     2.8      M    M
 11500  -14.5   5.9   295   19   10   7.9   4.3    5.6  42.1     2.5      M    M
 11000  -13.3   8.1   300   18    9   8.3   4.6    5.3  41.6     2.2      M    M
 10500  -12.4   9.7   300   17    9   3.7   2.1    4.7  40.5     1.6      M    M
 10250  -12.1  10.2   305   17    9   4.8   2.6    4.3  39.8     1.2      M    M
 10000  -11.7  10.9   305   16    8   7.8   4.3    4.0  39.2     0.9      M    M
  9750  -11.0  12.2   305   16    8   9.7   5.3    4.0  39.1     0.9      M    M
  9500  -10.3  13.5   305   15    8   9.3   5.1    3.9  39.1     0.8      M    M
  9250   -9.6  14.7   310   14    7   9.4   5.1    3.9  39.0     0.8      M    M
  9000   -8.9  16.0   310   13    7   9.3   5.1    3.9  39.0     0.8      M    M
  8750   -8.2  17.2   310   13    6   9.4   5.1    3.9  38.9     0.8      M    M
  8500   -7.5  18.5   305   12    6   9.3   5.1    3.8  38.9     0.7      M    M
  8250   -6.8  19.8   305   12    6   9.4   5.1    3.8  38.8     0.7      M    M
  8000   -6.1  21.0   300   11    6   9.3   5.1    3.8  38.8     0.7      M    M
  7750   -5.4  22.3   295   10    5   9.6   5.3    3.7  38.7     0.6      M    M
  7500   -4.7  23.5   290    9    4   8.4   4.6    3.7  38.7     0.6      M    M
  7250   -4.2  24.4   285    7    4   4.2   2.3    3.4  38.2     0.3      M    M
  7000   -4.0  24.8   275    6    3   3.3   1.8    2.9  37.3    -0.2     82  0.4
  6750   -3.7  25.3   275    5    3   6.6   3.6    2.6  36.6    -0.6     64  0.3
  6500   -3.1  26.4   290    4    2   7.8   4.3    2.4  36.3    -0.7     40  0.2
  6250   -2.5  27.5   315    3    2   7.5   4.1    2.2  36.0    -0.9     16  0.1
  6000   -2.0  28.4   345    3    1   7.7   4.2    2.1  35.7    -1.1      M    M
  5750   -1.4  29.5   355    3    1   7.4   4.0    1.9  35.4    -1.3      M    M
  5500   -0.9  30.4   350    2    1   8.4   4.6    1.7  35.1    -1.4      M    M
  5250   -0.3  31.5   345    2    1   4.6   2.5    1.6  34.8    -1.6      M    M
  5000   -0.5  31.1   335    1    1 -12.7  -6.9    0.6  33.1    -2.6      M    M

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

           01/22/2017 at 0800 MST          |       01/22/2017 at 1100 MST
                                           |
K index... -13.1  LI... +11.0              | K index... -3.0  LI... +11.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.1
                                           |
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 -58.4 -73.1  275  49 25   2.9   1.6 | -58.9 -74.0  270  41 21   2.7   1.5
 45000 -53.8 -64.8  275  80 41   2.5   1.4 | -54.8 -66.6  275  62 32   2.6   1.4
 40000 -51.0 -59.8  300  95 49   1.8   1.0 | -50.9 -59.6  295 101 52   2.6   1.4
 38000 -50.1 -58.2  305 108 55   1.1   0.6 | -49.9 -57.8  300 116 60   0.5   0.3
 36000 -49.5 -57.1  305 126 65   1.1   0.6 | -49.6 -57.3  295 126 65   0.6   0.3
 34000 -48.8 -55.8  300 144 74   2.0   1.1 | -49.2 -56.6  295 136 70   4.0   2.2
 32000 -45.2 -49.4  300 136 70   5.5   3.0 | -44.7 -48.5  295 127 66   6.6   3.6
 30000 -41.9 -43.4  300 126 65   5.8   3.2 | -40.9 -41.6  295 119 61   4.5   2.5
 29000 -40.3 -40.5  305 119 61   5.6   3.0 | -39.6 -39.3  295 111 57   4.5   2.5
 28000 -38.6 -37.5  305 111 57   5.6   3.1 | -38.3 -36.9  295 104 53   4.5   2.5
 27000 -36.9 -34.4  305 104 54   5.6   3.1 | -36.9 -34.4  295  96 49   4.3   2.3
 26000 -35.3 -31.5  305  98 50   5.0   2.7 | -35.2 -31.4  295  90 46   6.4   3.5
 25000 -33.8 -28.8  300  92 47   5.0   2.7 | -33.2 -27.8  295  85 44   6.4   3.5
 24000 -32.4 -26.3  300  86 45   5.1   2.8 | -31.3 -24.3  295  80 41   6.4   3.5
 23000 -30.6 -23.1  300  81 42   6.7   3.7 | -29.1 -20.4  290  76 39   8.1   4.5
 22000 -28.6 -19.5  305  75 39   6.7   3.7 | -26.6 -15.9  290  73 37   8.2   4.5
 21000 -26.6 -15.9  310  70 36   6.7   3.7 | -24.2 -11.6  285  70 36   8.4   4.6
 20000 -24.6 -12.3  310  63 32   6.5   3.6 | -22.5  -8.5  290  59 30   5.0   2.7
 19500 -23.6 -10.5  310  58 30   6.5   3.6 | -21.8  -7.2  295  53 27   5.0   2.7
 19000 -22.7  -8.9  305  54 28   6.5   3.6 | -21.0  -5.8  295  47 24   5.0   2.7
 18500 -21.7  -7.1  305  50 26   6.5   3.6 | -20.2  -4.4  300  41 21   4.7   2.6
 18000 -20.7  -5.3  300  46 24   7.0   3.8 | -19.3  -2.7  300  37 19   7.8   4.3
 17500 -19.6  -3.3  295  47 24   7.1   3.9 | -18.2  -0.8  300  35 18   7.6   4.2
 17000 -18.5  -1.3  295  48 24   6.5   3.6 | -17.0   1.4  290  33 17   6.5   3.6
 16500 -17.8  -0.0  290  46 24   4.5   2.5 | -16.2   2.8  285  33 17   5.3   2.9
 16000 -17.1   1.2  290  45 23   5.1   2.8 | -15.5   4.1  280  34 17   5.0   2.8
 15500 -16.7   1.9  295  41 21  -0.3  -0.2 | -14.8   5.4  275  33 17   2.5   1.3
 15000 -16.7   1.9  295  35 18   0.3   0.2 | -14.4   6.1  275  33 17   1.6   0.9
 14500 -16.6   2.1  295  31 16   1.1   0.6 | -14.4   6.1  270  30 16   0.3   0.2
 14000 -16.4   2.5  295  27 14   1.1   0.6 | -14.3   6.3  270  28 14   0.3   0.2
 13500 -16.0   3.2  290  24 12   3.4   1.9 | -14.2   6.4  265  25 13   0.3   0.1
 13000 -15.6   3.9  290  21 11   3.2   1.7 | -14.2   6.4  260  23 12   0.8   0.4
 12500 -15.0   5.0  290  18  9   4.9   2.7 | -13.8   7.2  255  21 11   4.1   2.3
 12000 -14.3   6.3  285  15  8   4.8   2.7 | -13.2   8.2  250  19 10   4.1   2.3
 11500 -13.5   7.7  285  12  6   5.9   3.2 | -12.4   9.7  245  17  9   5.4   3.0
 11000 -12.7   9.1  280  10  5   5.9   3.2 | -11.7  10.9  240  16  8   5.5   3.0
 10500 -11.8  10.8  275   8  4   6.2   3.4 | -10.8  12.6  235  14  7   6.0   3.3
 10250 -11.4  11.5  270   7  4   5.5   3.0 | -10.4  13.3  230  14  7   6.7   3.7
 10000 -10.9  12.4  270   7  3   8.2   4.5 |  -9.9  14.2  225  13  7   4.0   2.2
  9750 -10.2  13.6  265   6  3   9.0   4.9 |  -9.7  14.5  225  13  7   4.6   2.5
  9500  -9.7  14.5  255   6  3   6.9   3.8 |  -9.2  15.4  220  12  6   7.8   4.3
  9250  -9.1  15.6  250   6  3   7.7   4.2 |  -8.7  16.3  215  12  6   6.7   3.7
  9000  -8.6  16.5  240   6  3   6.0   3.3 |  -8.2  17.2  210  12  6   5.6   3.1
  8750  -8.2  17.2  230   6  3   5.0   2.8 |  -7.8  18.0  205  12  6   6.1   3.3
  8500  -7.8  18.0  220   7  3   5.8   3.2 |  -7.3  18.9  200  12  6   7.3   4.0
  8250  -7.4  18.7  215   7  4   5.6   3.1 |  -6.8  19.8  195  12  6   6.4   3.5
  8000  -7.0  19.4  205   7  4   5.5   3.0 |  -6.4  20.5  195  12  6   5.6   3.1
  7750  -6.6  20.1  200   7  4   4.6   2.5 |  -5.9  21.4  190  12  6   5.5   3.0
  7500  -6.3  20.7  195   7  4   4.0   2.2 |  -5.6  21.9  185  12  6   5.2   2.8
  7250  -6.0  21.2  190   7  3   4.4   2.4 |  -5.2  22.6  180  12  6   4.4   2.4
  7000  -5.7  21.7  185   6  3   4.6   2.5 |  -4.9  23.2  175  11  6   4.2   2.3
  6750  -5.3  22.5  175   6  3   4.3   2.4 |  -4.6  23.7  170  10  5   4.0   2.2
  6500  -5.0  23.0  170   6  3   4.7   2.6 |  -4.3  24.3  165   9  5   7.3   4.0
  6250  -4.6  23.7  160   5  3   4.9   2.7 |  -3.6  25.5  165   8  4  10.4   5.7
  6000  -4.3  24.3  155   5  3   5.8   3.2 |  -2.9  26.8  165   8  4   9.2   5.0
  5750  -3.9  25.0  140   5  3   2.9   1.6 |  -2.3  27.9  165   7  4   8.7   4.8
  5500  -4.0  24.8  125   5  2  -3.7  -2.0 |  -1.6  29.1  165   7  4   8.9   4.9
  5250  -4.4  24.1  120   4  2  -5.0  -2.7 |  -1.0  30.2  165   6  3   9.3   5.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/22/2017 at 1400 MST          |       01/22/2017 at 1700 MST
                                           |
K index... +5.1  LI... +11.4               | K index... +7.7  LI... +9.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -4.1
                                           |
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 -59.9 -75.8  265  44 22   1.5   0.8 | -60.3 -76.5  255  49 25   1.9   1.0
 45000 -57.5 -71.5  265  47 24   3.5   1.9 | -57.2 -71.0  265  66 34   4.7   2.6
 40000 -51.3 -60.3  285  94 48   4.1   2.2 | -49.2 -56.6  285  86 44   5.4   2.9
 38000 -49.9 -57.8  285 112 58   0.7   0.4 | -47.9 -54.2  285 103 53  -1.4  -0.7
 36000 -49.5 -57.1  285 129 66   0.7   0.4 | -48.7 -55.7  280 127 66  -1.4  -0.7
 34000 -48.9 -56.0  285 144 74   4.9   2.7 | -49.3 -56.7  280 151 78   4.0   2.2
 32000 -45.2 -49.4  285 135 70   6.1   3.4 | -46.0 -50.8  280 138 71   5.5   3.0
 30000 -41.1 -42.0  285 125 65   5.5   3.0 | -42.7 -44.9  275 126 65   5.9   3.2
 29000 -39.4 -38.9  285 121 63   5.7   3.1 | -40.5 -40.9  275 110 57   5.8   3.2
 28000 -37.7 -35.9  290 117 60   5.7   3.1 | -38.8 -37.8  270  98 50   5.8   3.2
 27000 -36.0 -32.8  290 113 58   5.7   3.1 | -37.1 -34.8  265  87 45   5.9   3.2
 26000 -34.3 -29.7  290 103 53   5.5   3.0 | -34.6 -30.3  265  83 43   9.0   5.0
 25000 -32.7 -26.9  285  90 46   5.5   3.0 | -31.9 -25.4  265  81 42   9.0   5.0
 24000 -31.1 -24.0  285  77 40   5.3   2.9 | -29.2 -20.6  260  79 41   9.3   5.1
 23000 -28.9 -20.0  285  71 37   7.9   4.4 | -27.0 -16.6  260  73 38   6.6   3.6
 22000 -26.6 -15.9  285  69 35   8.0   4.4 | -25.0 -13.0  260  65 33   6.7   3.6
 21000 -24.2 -11.6  285  66 34   8.0   4.4 | -23.1  -9.6  265  57 29   6.6   3.6
 20000 -21.8  -7.2  280  63 32   8.0   4.4 | -21.2  -6.2  265  50 26   6.1   3.4
 19500 -20.6  -5.1  280  61 31   8.0   4.4 | -20.3  -4.5  270  48 24   6.2   3.4
 19000 -19.5  -3.1  280  59 31   8.1   4.4 | -19.4  -2.9  270  45 23   6.2   3.4
 18500 -18.3  -0.9  280  58 30   8.3   4.5 | -18.5  -1.3  275  42 22   6.2   3.4
 18000 -17.2   1.0  275  55 28   6.1   3.4 | -17.6   0.3  280  41 21   5.5   3.0
 17500 -16.3   2.7  275  51 26   6.3   3.5 | -16.8   1.8  285  41 21   5.6   3.0
 17000 -15.4   4.3  275  47 24   5.2   2.8 | -16.0   3.2  290  42 22   5.5   3.0
 16500 -14.7   5.5  270  42 22   4.4   2.4 | -15.2   4.6  290  38 20   5.4   3.0
 16000 -14.1   6.6  270  37 19   4.7   2.6 | -14.4   6.1  295  34 18   5.6   3.1
 15500 -13.1   8.4  270  35 18   7.5   4.1 | -13.4   7.9  290  32 16   7.2   4.0
 15000 -12.0  10.4  270  34 18   7.7   4.2 | -12.4   9.7  280  29 15   7.5   4.1
 14500 -10.8  12.6  265  34 17   4.7   2.6 | -11.6  11.1  270  28 14   3.4   1.8
 14000 -10.1  13.8  265  33 17   3.6   2.0 | -10.8  12.6  255  27 14   3.1   1.7
 13500 -10.0  14.0  260  31 16  -0.8  -0.4 | -10.5  13.1  250  27 14   1.2   0.7
 13000 -10.0  14.0  255  28 14  -0.6  -0.3 | -10.3  13.5  245  28 14   1.3   0.7
 12500 -10.1  13.8  250  25 13  -0.9  -0.5 | -10.3  13.5  245  28 15  -0.4  -0.2
 12000 -10.2  13.6  245  22 11  -0.7  -0.4 | -10.3  13.5  245  29 15  -0.2  -0.1
 11500 -10.1  13.8  240  20 10   1.8   1.0 | -10.3  13.5  240  29 15   0.6   0.3
 11000  -9.8  14.4  235  19 10   1.9   1.0 | -10.2  13.6  240  28 14   1.1   0.6
 10500  -9.4  15.1  230  18  9   3.5   1.9 |  -9.6  14.7  235  27 14   5.7   3.1
 10250  -9.2  15.4  225  17  9   2.4   1.3 |  -9.2  15.4  230  27 14   4.8   2.7
 10000  -9.0  15.8  220  16  8   6.1   3.3 |  -8.8  16.2  230  27 14   7.0   3.8
  9750  -8.4  16.9  220  16  8   8.2   4.5 |  -8.2  17.2  225  26 13   7.9   4.3
  9500  -7.9  17.8  215  16  8   6.3   3.4 |  -7.7  18.1  225  26 13   6.7   3.7
  9250  -7.4  18.7  210  16  8   6.8   3.8 |  -7.2  19.0  225  25 13   6.7   3.7
  9000  -6.9  19.6  205  16  8   6.3   3.5 |  -6.7  19.9  220  25 13   8.0   4.4
  8750  -6.5  20.3  205  16  8   6.5   3.6 |  -6.1  21.0  220  24 12   8.8   4.8
  8500  -6.0  21.2  200  16  8   7.0   3.8 |  -5.5  22.1  220  23 12   8.0   4.4
  8250  -5.5  22.1  195  16  8   6.8   3.8 |  -4.9  23.2  220  22 12   8.3   4.6
  8000  -5.0  23.0  190  16  8   6.6   3.6 |  -4.2  24.4  215  22 11   8.4   4.6
  7750  -4.5  23.9  180  16  8   5.8   3.2 |  -3.6  25.5  215  21 11   7.9   4.3
  7500  -4.1  24.6  175  15  8   5.3   2.9 |  -3.0  26.6  210  20 10   7.7   4.2
  7250  -3.7  25.3  170  15  8   6.0   3.3 |  -2.5  27.5  210  20 10   7.4   4.1
  7000  -3.3  26.1  165  14  7   6.6   3.6 |  -1.9  28.6  205  19 10   6.9   3.8
  6750  -2.8  27.0  160  14  7   6.9   3.8 |  -1.5  29.3  195  18  9   6.0   3.3
  6500  -2.2  28.0  160  13  7   8.6   4.7 |  -1.0  30.2  190  17  9   5.9   3.2
  6250  -1.5  29.3  160  12  6  10.1   5.5 |  -0.6  30.9  185  15  8   6.9   3.8
  6000  -0.8  30.6  160  12  6  10.3   5.7 |  -0.1  31.8  185  13  7   7.1   3.9
  5750  -0.0  32.0  160  11  6   9.5   5.2 |   0.4  32.7  180  11  6   5.7   3.2
  5500   0.6  33.1  160  10  5   7.8   4.3 |   0.7  33.3  180   9  5   2.4   1.3
  5250   1.1  34.0  160  10  5   7.1   3.9 |   0.8  33.4  180   8  4   0.0   0.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 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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