Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271226
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0626 MDT Monday, March 27, 2017

This forecast is for Monday, March 27, 2017:

If the trigger temperature of 56.8 F/13.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 594 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14230 ft MSL (9391 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10560 ft MSL (5720 ft AGL)
Thermal soaring outlook for Tuesday 03/28...... Good

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

Remarks...

Sunrise/Sunset.................... 07:05:59 / 19:32:20 MDT
Total possible sunshine........... 12 hr 26 min 22 sec (746 min 22 sec)
Altitude of sun at 13:19:19 MDT... 53.79 degrees

Upper air data from rawinsonde observation taken on 03/27/2017 at 0600 MDT

Freezing level.................. 9530 ft MSL (4691 ft AGL)
Convective condensation level... 16246 ft MSL (11407 ft AGL)
Lifted condensation level....... 14602 ft MSL (9763 ft AGL)
Lifted index.................... +4.8
K index......................... +10.8

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  -61.9 -79.4   250   38   20   2.1   1.2   98.3 209.0    45.8      M    M
 45000  -54.7 -66.5   270   57   30   0.0   0.0   84.5 184.1    40.8      M    M
 40000  -54.5 -66.1   255   71   37   1.1   0.6   61.6 142.8    28.6      M    M
 38000  -59.3 -74.7   260   86   44 -15.3  -8.4   45.6 114.0    18.6      M    M
 36000  -55.8 -68.4   265   90   46   7.1   3.9   42.0 107.6    16.7      M    M
 34000  -51.5 -60.7   265   86   44   7.2   3.9   39.8 103.6    15.6      M    M
 32000  -47.4 -53.3   260   82   42   6.8   3.8   36.5  97.6    13.6      M    M
 30000  -42.6 -44.7   255   77   39   7.0   3.8   35.0  94.9    12.8      M    M
 29000  -40.3 -40.5   255   72   37   8.6   4.7   34.2  93.5    12.4      M    M
 28000  -38.2 -36.8   255   68   35   6.8   3.7   33.1  91.5    11.7      M    M
 27000  -36.0 -32.8   250   63   32   7.6   4.2   32.2  89.9    11.2      M    M
 26000  -33.6 -28.5   250   59   30   8.2   4.5   31.5  88.7    10.8      M    M
 25000  -31.1 -24.0   250   54   28   8.2   4.5   31.0  87.7    10.5      M    M
 24000  -28.7 -19.7   250   50   26   8.2   4.5   30.4  86.7    10.1      M    M
 23000  -26.2 -15.2   250   45   23   8.4   4.6   29.8  85.6     9.8      M    M
 22000  -23.6 -10.5   255   41   21   8.4   4.6   29.3  84.7     9.5      M    M
 21000  -21.3  -6.3   255   37   19   5.1   2.8   28.7  83.7     9.1      M    M
 20000  -21.5  -6.7   245   33   17  -0.9  -0.5   24.9  76.9     6.0      M    M
 19500  -20.4  -4.7   240   32   17  11.6   6.4   24.8  76.6     5.7      M    M
 19000  -19.0  -2.2   235   32   17   7.6   4.2   24.7  76.5     5.7      M    M
 18500  -17.9  -0.2   240   30   15   6.8   3.7   24.2  75.6     5.3      M    M
 18000  -16.5   2.3   240   29   15   8.8   4.8   23.4  74.0     4.6      M    M
 17500  -15.3   4.5   240   30   15   8.5   4.6   23.1  73.6     4.4      M    M
 17000  -14.0   6.8   240   30   16   9.4   5.2   22.9  73.2     4.2      M    M
 16500  -12.6   9.3   240   31   16  10.6   5.8   23.0  73.3     4.2      M    M
 16000  -11.5  11.3   240   31   16   1.4   0.8   22.6  72.6     3.9      M    M
 15500  -11.3  11.7   245   29   15   3.4   1.8   21.1  70.1     2.6      M    M
 15000  -10.8  12.6   245   26   14   2.0   1.1   20.1  68.2     1.7      M    M
 14500  -10.6  12.9   240   22   11   1.1   0.6   18.6  65.4     0.4      M    M
 14000   -9.9  14.2   230   19   10   8.1   4.4   17.7  63.9    -0.3    769  3.9
 13500   -8.6  16.5   230   17    9   8.5   4.7   17.5  63.5    -0.5    716  3.6
 13000   -7.3  18.9   230   16    8   8.4   4.6   17.3  63.1    -0.7    664  3.4
 12500   -6.2  20.8   230   14    7   4.3   2.3   16.7  62.1    -1.0    615  3.1
 12000   -5.6  21.9   230   13    7   6.3   3.5   16.0  60.7    -1.9    582  3.0
 11500   -4.4  24.1   230   12    6   7.2   3.9   15.6  60.1    -2.2    531  2.7
 11000   -3.4  25.9   230   12    6   7.5   4.1   15.1  59.3    -2.7    488  2.5
 10500   -2.3  27.9   235   11    6   7.8   4.3   14.8  58.6    -3.0    439  2.2
 10250   -1.8  28.8   235   11    6   9.1   5.0   14.7  58.4    -3.3    416  2.1
 10000   -1.2  29.8   235   11    6   7.7   4.2   14.6  58.3    -3.4    390  2.0
  9750   -0.6  30.9   235    9    5   7.5   4.1   14.4  57.9    -3.6    366  1.9
  9500    0.0  32.0   240    8    4   9.2   5.1   14.3  57.8    -3.6    339  1.7
  9250    0.7  33.3   245    6    3   8.8   4.8   14.3  57.7    -3.7    312  1.6
  9000    1.3  34.3   250    5    3   8.9   4.9   14.2  57.6    -3.8    285  1.4
  8750    2.0  35.6   250    5    2   8.9   4.9   14.1  57.4    -3.9    258  1.3
  8500    2.6  36.7   250    4    2   8.9   4.9   14.1  57.3    -4.0    231  1.2
  8250    3.3  37.9   255    4    2   8.9   4.9   14.0  57.2    -4.0    204  1.0
  8000    4.0  39.2   255    3    2   8.9   4.9   14.0  57.1    -4.1    177  0.9
  7750    4.6  40.3   220    3    1   8.9   4.9   13.9  57.0    -4.2    150  0.8
  7500    5.3  41.5   185    4    2   8.9   4.9   13.8  56.9    -4.3    123  0.6
  7250    5.9  42.6   170    6    3   9.0   4.9   13.7  56.7    -4.4     97  0.5
  7000    6.6  43.9   160    8    4   8.6   4.7   13.7  56.6    -4.5     70  0.4
  6750    7.2  45.0   160   10    5  10.1   5.6   13.6  56.5    -4.6     43  0.2
  6500    7.7  45.9   155   13    7  -1.0  -0.5   13.4  56.1    -4.8     20  0.1
  6250    7.2  45.0   155   16    8  -2.3  -1.3   12.2  54.0    -6.1     27  0.1
  6000    7.6  45.7   155   19   10   6.0   3.3   11.8  53.3    -6.5     10  0.1
  5750    7.9  46.2   155   18    9   4.8   2.6   11.4  52.5    -6.9      M    M
  5500    8.2  46.8   150   14    7   0.6   0.4   11.0  51.8    -7.3      M    M
  5250    8.0  46.4   140   11    6  -5.0  -2.8   10.0  50.0    -8.3      M    M
  5000    7.7  45.9   130    8    4  -0.9  -0.5    9.0  48.2    -9.3      M    M

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

           03/27/2017 at 0900 MDT          |       03/27/2017 at 1200 MDT
                                           |
K index... +18.8  LI... +4.4               | K index... +20.4  LI... +2.8
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 -61.1 -78.0  255  34 18   4.3   2.3 | -59.4 -74.9  240  37 19   3.7   2.1
 45000 -54.5 -66.1  250  52 27   0.3   0.2 | -53.5 -64.3  245  53 27   0.6   0.3
 40000 -56.4 -69.5  255  83 43  -1.3  -0.7 | -55.9 -68.6  245  81 42  -1.6  -0.9
 38000 -55.8 -68.4  255  90 47   3.3   1.8 | -55.6 -68.1  245  89 46   3.3   1.8
 36000 -53.9 -65.0  255  92 48   3.3   1.8 | -53.6 -64.5  245  93 48   3.3   1.8
 34000 -51.7 -61.1  250  93 48   6.7   3.7 | -51.5 -60.7  240  96 49   6.0   3.3
 32000 -47.7 -53.9  250  85 44   6.6   3.6 | -47.7 -53.9  240  87 45   6.4   3.5
 30000 -43.0 -45.4  245  76 39   8.1   4.4 | -43.3 -45.9  235  77 40   7.0   3.8
 29000 -40.6 -41.1  245  73 37   8.2   4.5 | -41.2 -42.2  235  73 38   7.0   3.9
 28000 -38.1 -36.6  240  69 36   8.2   4.5 | -39.1 -38.4  235  69 35   7.0   3.9
 27000 -35.7 -32.3  240  66 34   7.9   4.3 | -36.9 -34.4  235  64 33   7.3   4.0
 26000 -33.4 -28.1  240  62 32   7.5   4.1 | -34.6 -30.3  235  61 31   8.0   4.4
 25000 -31.2 -24.2  240  58 30   7.5   4.1 | -32.2 -26.0  235  58 30   8.0   4.4
 24000 -28.9 -20.0  240  53 27   7.5   4.1 | -29.7 -21.5  235  54 28   8.0   4.4
 23000 -26.6 -15.9  235  48 25   7.9   4.3 | -27.3 -17.1  230  51 26   8.0   4.4
 22000 -24.2 -11.6  235  43 22   7.8   4.3 | -24.9 -12.8  230  48 25   8.0   4.4
 21000 -21.9  -7.4  230  38 20   7.3   4.0 | -22.6  -8.7  225  45 23   7.1   3.9
 20000 -19.9  -3.8  230  37 19   6.7   3.7 | -21.0  -5.8  230  43 22   5.4   2.9
 19500 -18.9  -2.0  230  36 18   6.7   3.7 | -20.2  -4.4  235  42 21   5.4   3.0
 19000 -17.9  -0.2  230  35 18   6.7   3.7 | -19.4  -2.9  235  41 21   5.5   3.0
 18500 -16.9   1.6  230  35 18   6.1   3.3 | -18.6  -1.5  235  40 21   5.6   3.1
 18000 -16.3   2.7  230  34 17   2.8   1.6 | -17.8  -0.0  240  38 20   5.8   3.2
 17500 -15.9   3.4  235  33 17   3.1   1.7 | -16.9   1.6  240  36 19   5.8   3.2
 17000 -15.4   4.3  235  31 16   4.5   2.5 | -16.1   3.0  240  34 17   6.2   3.4
 16500 -14.8   5.4  235  29 15   4.7   2.6 | -15.2   4.6  240  31 16   6.2   3.4
 16000 -14.2   6.4  240  27 14   5.9   3.2 | -14.2   6.4  240  27 14   6.0   3.3
 15500 -13.1   8.4  240  26 13   7.3   4.0 | -13.4   7.9  240  24 13   5.6   3.1
 15000 -12.0  10.4  240  24 12   7.2   3.9 | -12.6   9.3  240  21 11   5.7   3.1
 14500 -10.7  12.7  240  21 11   5.8   3.2 | -11.0  12.2  240  19 10   7.6   4.1
 14000  -9.8  14.4  235  20 10   6.1   3.4 |  -9.9  14.2  235  18  9   6.9   3.8
 13500  -8.9  16.0  235  18  9   6.4   3.5 |  -9.0  15.8  230  18  9   6.0   3.3
 13000  -7.9  17.8  230  17  9   6.5   3.6 |  -8.1  17.4  225  18  9   6.1   3.3
 12500  -7.0  19.4  230  16  8   6.5   3.6 |  -7.2  19.0  220  18  9   6.3   3.4
 12000  -6.0  21.2  225  15  8   6.5   3.6 |  -6.3  20.7  215  18  9   6.5   3.6
 11500  -5.0  23.0  220  13  7   6.5   3.6 |  -5.3  22.5  215  18  9   7.0   3.9
 11000  -4.1  24.6  215  12  6   6.1   3.4 |  -4.2  24.4  210  17  9   6.9   3.8
 10500  -3.2  26.2  210  11  5   5.0   2.8 |  -3.2  26.2  210  17  9   6.4   3.5
 10250  -2.8  27.0  210  10  5   7.4   4.1 |  -2.7  27.1  210  17  9   8.1   4.5
 10000  -2.2  28.0  210   9  5   8.3   4.6 |  -2.0  28.4  210  17  9   9.0   4.9
  9750  -1.6  29.1  205   9  5   6.2   3.4 |  -1.4  29.5  205  16  8   7.4   4.1
  9500  -1.2  29.8  205   9  4   6.5   3.6 |  -0.9  30.4  205  16  8   7.5   4.1
  9250  -0.7  30.7  205   8  4   6.3   3.4 |  -0.3  31.5  205  15  8   7.2   3.9
  9000  -0.2  31.6  205   8  4   6.5   3.6 |   0.2  32.4  200  15  8   7.3   4.0
  8750   0.3  32.5  200   8  4   6.9   3.8 |   0.8  33.4  200  14  7   7.7   4.2
  8500   0.8  33.4  200   8  4   6.7   3.7 |   1.3  34.3  195  13  7   7.4   4.1
  8250   1.3  34.3  195   8  4   7.4   4.1 |   1.9  35.4  190  13  6   8.0   4.4
  8000   1.9  35.4  195   9  4   7.7   4.2 |   2.5  36.5  185  12  6   7.9   4.3
  7750   2.4  36.3  190   9  5   6.2   3.4 |   3.0  37.4  185  12  6   6.8   3.7
  7500   2.9  37.2  185  10  5   5.8   3.2 |   3.5  38.3  180  11  6   6.1   3.4
  7250   3.3  37.9  180  11  6   5.8   3.2 |   4.0  39.2  175  11  6   7.5   4.1
  7000   3.7  38.7  175  11  6   5.2   2.8 |   4.7  40.5  175  11  6   8.8   4.8
  6750   4.1  39.4  175  11  6   4.4   2.4 |   5.3  41.5  175  10  5   8.1   4.5
  6500   4.3  39.7  170  10  5   2.6   1.4 |   5.9  42.6  175  10  5   8.7   4.7
  6250   4.4  39.9  165   9  5   0.5   0.3 |   6.6  43.9  175   9  5  10.3   5.6
  6000   4.4  39.9  155   7  4  -0.4  -0.2 |   7.4  45.3  175   9  5  10.7   5.9
  5750   4.3  39.7  140   5  3  -1.3  -0.7 |   8.2  46.8  180   8  4  10.4   5.7
  5500   4.2  39.6  100   4  2  -0.7  -0.4 |   8.9  48.0  180   8  4   8.0   4.4
  5250   4.2  39.6  095   3  2   1.8   1.0 |   9.3  48.7  180   7  4   3.8   2.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/27/2017 at 1500 MDT          |       03/27/2017 at 1800 MDT
                                           |
K index... +23.0  LI... +1.1               | K index... +27.4  LI... -1.5
CAPE... 0.0  CIN... 0.0                    | CAPE... +117.2  CIN... -4.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.0 -72.4  240  37 19   3.3   1.8 | -57.8 -72.0  245  34 17   2.9   1.6
 45000 -52.9 -63.2  245  51 26   0.9   0.5 | -53.5 -64.3  240  46 23   3.2   1.7
 40000 -55.1 -67.2  240  77 39  -1.5  -0.8 | -54.3 -65.7  235  69 36  -0.7  -0.4
 38000 -54.9 -66.8  235  84 43   2.9   1.6 | -54.0 -65.2  235  78 40   2.6   1.4
 36000 -53.2 -63.8  235  88 46   2.9   1.6 | -52.4 -62.3  230  84 43   2.6   1.4
 34000 -51.4 -60.5  235  92 47   5.2   2.9 | -50.9 -59.6  230  91 47   4.0   2.2
 32000 -47.7 -53.9  235  89 46   6.2   3.4 | -47.5 -53.5  225  85 44   5.6   3.1
 30000 -43.5 -46.3  235  84 43   6.2   3.4 | -44.2 -47.6  225  78 40   5.3   2.9
 29000 -41.6 -42.9  235  79 41   6.2   3.4 | -42.4 -44.3  225  72 37   4.9   2.7
 28000 -39.8 -39.6  230  73 38   6.2   3.4 | -40.9 -41.6  225  68 35   4.9   2.7
 27000 -37.9 -36.2  230  68 35   6.3   3.4 | -39.4 -38.9  225  63 32   4.7   2.6
 26000 -35.8 -32.4  230  64 33   7.4   4.1 | -37.5 -35.5  225  59 30   7.0   3.8
 25000 -33.5 -28.3  230  60 31   7.4   4.1 | -35.4 -31.7  225  55 28   7.0   3.8
 24000 -31.3 -24.3  230  55 28   7.3   4.0 | -33.3 -27.9  225  51 26   6.9   3.8
 23000 -29.0 -20.2  230  52 27   8.1   4.4 | -31.1 -24.0  225  47 24   7.7   4.2
 22000 -26.6 -15.9  230  49 25   8.1   4.4 | -28.8 -19.8  225  43 22   7.7   4.2
 21000 -24.1 -11.4  235  46 24   7.5   4.1 | -26.5 -15.7  230  38 20   7.7   4.2
 20000 -22.4  -8.3  230  40 20   5.9   3.2 | -24.3 -11.7  230  34 17   7.4   4.1
 19500 -21.5  -6.7  230  36 19   5.9   3.2 | -23.2  -9.8  230  31 16   7.4   4.1
 19000 -20.7  -5.3  230  33 17   6.0   3.3 | -22.1  -7.8  225  29 15   7.5   4.1
 18500 -19.8  -3.6  230  30 15   6.1   3.4 | -21.0  -5.8  225  27 14   7.5   4.1
 18000 -18.7  -1.7  225  28 14   8.3   4.6 | -19.9  -3.8  225  26 13   8.2   4.5
 17500 -17.6   0.3  225  27 14   8.2   4.5 | -18.7  -1.7  225  25 13   8.1   4.5
 17000 -16.4   2.5  225  26 13   8.4   4.6 | -17.5   0.5  225  25 13   8.3   4.6
 16500 -15.1   4.8  225  26 13   8.5   4.7 | -16.3   2.7  225  25 13   8.4   4.6
 16000 -13.9   7.0  225  27 14   7.9   4.4 | -15.0   5.0  225  25 13   8.4   4.6
 15500 -12.9   8.8  225  26 14   6.5   3.6 | -13.8   7.2  230  26 13   8.3   4.5
 15000 -11.9  10.6  225  26 13   6.6   3.6 | -12.6   9.3  230  27 14   8.4   4.6
 14500 -11.0  12.2  220  27 14   5.3   2.9 | -11.4  11.5  230  27 14   7.6   4.2
 14000  -9.8  14.4  220  28 14   5.6   3.1 | -10.3  13.5  225  26 13   7.7   4.2
 13500  -9.0  15.8  220  28 15   5.9   3.2 |  -8.7  16.3  220  26 14   7.0   3.8
 13000  -8.1  17.4  220  28 15   6.2   3.4 |  -7.7  18.1  215  27 14   7.0   3.8
 12500  -7.1  19.2  215  28 15   7.4   4.0 |  -6.7  19.9  215  27 14   7.0   3.8
 12000  -6.0  21.2  215  28 14   7.0   3.8 |  -5.7  21.7  210  27 14   7.0   3.9
 11500  -5.2  22.6  215  27 14   5.2   2.8 |  -4.6  23.7  205  26 14   7.5   4.1
 11000  -4.4  24.1  210  27 14   5.4   2.9 |  -3.5  25.7  200  25 13   7.5   4.1
 10500  -3.6  25.5  205  25 13   5.7   3.1 |  -2.4  27.7  200  24 12   7.6   4.2
 10250  -3.1  26.4  205  24 12   6.9   3.8 |  -1.8  28.8  200  22 12   8.5   4.7
 10000  -2.6  27.3  205  23 12   8.0   4.4 |  -1.1  30.0  200  22 11   9.5   5.2
  9750  -2.0  28.4  200  22 11   7.0   3.8 |  -0.4  31.3  195  21 11   9.1   5.0
  9500  -1.5  29.3  200  21 11   7.1   3.9 |   0.2  32.4  195  20 10   9.1   5.0
  9250  -1.0  30.2  200  19 10   5.7   3.1 |   0.9  33.6  190  19 10   8.9   4.9
  9000  -0.6  30.9  195  18  9   7.3   4.0 |   1.6  34.9  190  18  9   8.6   4.7
  8750   0.1  32.2  195  17  9   9.9   5.5 |   2.2  36.0  185  17  9   8.9   4.9
  8500   0.8  33.4  195  16  8   9.0   5.0 |   2.9  37.2  185  17  9   8.8   4.8
  8250   1.5  34.7  195  15  8  10.0   5.5 |   3.6  38.5  180  16  8   9.6   5.3
  8000   2.3  36.1  195  14  7  10.4   5.7 |   4.3  39.7  175  16  8  10.8   5.9
  7750   3.0  37.4  195  13  7   9.1   5.0 |   5.1  41.2  175  15  8   9.5   5.2
  7500   3.7  38.7  195  12  6   8.6   4.7 |   5.8  42.4  175  15  8   8.3   4.5
  7250   4.3  39.7  195  12  6   9.1   5.0 |   6.4  43.5  175  15  8   9.5   5.2
  7000   5.0  41.0  195  11  6   9.6   5.3 |   7.2  45.0  175  15  7  10.5   5.8
  6750   5.8  42.4  195  11  5   9.7   5.3 |   7.9  46.2  170  14  7   9.8   5.4
  6500   6.5  43.7  195  10  5   9.8   5.4 |   8.6  47.5  170  14  7   9.1   5.0
  6250   7.2  45.0  195  10  5  10.1   5.5 |   9.3  48.7  170  13  7   9.9   5.4
  6000   8.0  46.4  195   9  5  10.3   5.6 |  10.1  50.2  170  13  6  10.0   5.5
  5750   8.8  47.8  195   9  4  11.6   6.4 |  10.8  51.4  170  12  6   9.5   5.2
  5500   9.7  49.5  195   8  4  10.1   5.5 |  11.5  52.7  170  10  5   7.8   4.3
  5250  10.2  50.4  195   8  4   4.7   2.6 |  11.9  53.4  170  10  5   4.2   2.3
  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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