Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 020029
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1729 MST Sunday, February 1, 2015

This forecast is for Monday, February 2, 2015:

If the trigger temperature of 48.0 F/8.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 176 ft/min (0.9 m/s)
   Maximum height of thermals.................. 10899 ft MSL (5612 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1145 MST
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................. 9385 ft MSL (4097 ft AGL)
Thermal soaring outlook for Tuesday 02/03...... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Decreasing trend
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 14400 ft MSL (9113 ft AGL)
Wave soaring outlook for Tuesday 02/03......... Poor

Remarks... None

Sunrise/Sunset.................... 07:06:29 / 17:18:55 MST
Total possible sunshine........... 10 hr 12 min 26 sec (612 min 26 sec)
Altitude of sun at 12:13:04 MST... 33.54 degrees

Upper air data from numerical model forecast valid on 02/02/2015 at 0500 MST

Freezing level.................. 5416 ft MSL (129 ft AGL)
Additional freezing level....... 7474 ft MSL (2187 ft AGL)
Convective condensation level... 15783 ft MSL (10496 ft AGL)
Lifted condensation level....... 13586 ft MSL (8299 ft AGL)
Lifted index.................... +5.0
K index......................... +10.4

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -61.0 -77.8   290   32   17   1.8   1.0      M     M       M      M    M
 45000  -58.2 -72.8   305   42   22   1.9   1.0      M     M       M      M    M
 40000  -58.8 -73.8   305   59   31  -0.6  -0.3      M     M       M      M    M
 38000  -58.7 -73.7   305   65   33   2.1   1.1      M     M       M      M    M
 36000  -57.5 -71.5   305   67   34   2.1   1.2      M     M       M      M    M
 34000  -56.2 -69.2   305   68   35   3.7   2.1      M     M       M      M    M
 32000  -51.4 -60.5   310   67   35   7.3   4.0      M     M       M      M    M
 30000  -46.9 -52.4   310   66   34   8.8   4.8   28.8  83.8    12.4      M    M
 29000  -44.3 -47.7   310   65   33   8.7   4.7   28.2  82.8    12.1      M    M
 28000  -41.7 -43.1   310   64   33   8.7   4.7   27.8  82.0    11.9      M    M
 27000  -39.1 -38.4   310   62   32   8.7   4.8   27.5  81.5    11.9      M    M
 26000  -36.9 -34.4   305   55   28   7.2   4.0   26.6  79.8    11.3      M    M
 25000  -34.7 -30.5   300   46   24   7.2   4.0   25.6  78.0    10.6      M    M
 24000  -32.6 -26.7   295   37   19   7.2   3.9   24.7  76.5    10.0      M    M
 23000  -30.3 -22.5   295   34   17   7.8   4.3   23.9  75.0     9.5      M    M
 22000  -28.0 -18.4   300   32   17   7.8   4.3   23.2  73.7     8.9      M    M
 21000  -25.7 -14.3   310   31   16   7.7   4.2   22.5  72.6     8.5      M    M
 20000  -23.4 -10.1   315   32   16   7.5   4.1   21.7  71.0     7.9      M    M
 19500  -22.3  -8.1   315   32   16   7.5   4.1   21.3  70.3     7.6      M    M
 19000  -21.2  -6.2   315   32   17   7.5   4.1   20.9  69.6     7.3      M    M
 18500  -20.1  -4.2   320   32   17   7.6   4.1   20.6  69.0     7.0      M    M
 18000  -18.9  -2.0   320   32   17   7.6   4.2   20.2  68.4     6.7      M    M
 17500  -17.8  -0.0   320   32   17   7.6   4.2   19.8  67.7     6.4      M    M
 17000  -16.7   1.9   320   32   17   7.8   4.3   19.5  67.0     6.1      M    M
 16500  -15.5   4.1   320   33   17   7.8   4.3   19.1  66.4     5.9      M    M
 16000  -13.8   7.2   320   33   17   8.0   4.4   18.7  65.6     5.5      M    M
 15500  -12.6   9.3   320   33   17   8.0   4.4   18.4  65.0     5.2      M    M
 15000  -11.4  11.5   320   33   17   7.3   4.0   18.0  64.5     5.0      M    M
 14500  -10.4  13.3   320   34   18   6.9   3.8   17.6  63.6     4.6      M    M
 14000   -9.3  15.3   320   35   18   6.6   3.6   17.1  62.8     4.2      M    M
 13500   -8.4  16.9   315   36   19   6.1   3.3   16.5  61.7     3.6      M    M
 13000   -7.5  18.5   315   37   19   5.9   3.2   15.9  60.6     3.1      M    M
 12500   -6.7  19.9   315   38   20   5.3   2.9   15.2  59.4     2.4      M    M
 12000   -5.9  21.4   310   39   20   5.0   2.8   14.5  58.1     1.8      M    M
 11500   -5.3  22.5   310   40   21   4.0   2.2   13.6  56.5     1.0      M    M
 11000   -4.7  23.5   305   42   21   3.8   2.1   12.7  54.9     0.1      M    M
 10500   -4.2  24.4   305   42   21   2.9   1.6   11.6  53.0    -0.9    350  1.8
 10250   -4.0  24.8   300   42   21   2.6   1.4   11.1  52.0    -1.4    337  1.7
 10000   -3.8  25.2   300   41   21   4.1   2.3   10.6  51.0    -1.9    323  1.6
  9750   -3.4  25.9   300   40   21   4.4   2.4   10.2  50.3    -2.3    305  1.5
  9500   -3.2  26.2   295   39   20   3.1   1.7    9.7  49.4    -2.8    290  1.5
  9250   -3.0  26.6   295   37   19   3.4   1.9    9.2  48.5    -3.3    275  1.4
  9000   -2.7  27.1   295   36   19   3.4   1.8    8.7  47.6    -3.8    260  1.3
  8750   -2.4  27.7   295   34   17   4.9   2.7    8.2  46.8    -4.3    244  1.2
  8500   -2.0  28.4   290   31   16   5.7   3.1    7.9  46.2    -4.6    225  1.1
  8250   -1.6  29.1   290   29   15   5.8   3.2    7.6  45.6    -4.9    205  1.0
  8000   -1.1  30.0   290   26   14   7.0   3.8    7.3  45.2    -5.2    183  0.9
  7750   -0.6  30.9   290   24   12   7.1   3.9    7.1  44.8    -5.4    160  0.8
  7500   -0.1  31.8   290   22   11   7.2   3.9    6.9  44.4    -5.6    137  0.7
  7250    0.5  32.9   290   19   10   6.1   3.3    6.7  44.1    -5.8    114  0.6
  7000    0.8  33.4   285   17    9   4.9   2.7    6.3  43.4    -6.2     95  0.5
  6750    1.2  34.2   285   14    7   5.4   2.9    6.0  42.8    -6.6     76  0.4
  6500    1.6  34.9   280   11    6   3.8   2.1    5.6  42.1    -6.9     57  0.3
  6250    1.8  35.2   265    9    5   1.2   0.6    5.1  41.1    -7.5     44  0.2
  6000    1.8  35.2   245    8    4   1.3   0.7    4.4  39.9    -8.2     35  0.2
  5750    1.9  35.4   225    8    4   0.9   0.5    3.8  38.8    -8.8     25  0.1
  5500    1.5  34.7   215    9    4 -15.6  -8.5    2.7  36.8   -10.0     29  0.1

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

           02/02/2015 at 0800 MST          |       02/02/2015 at 1100 MST
                                           |
K index... +8.0  LI... +4.6                | K index... +10.0  LI... +3.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
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 -61.3 -78.3  285  35 18   2.4   1.3 | -61.1 -78.0  280  35 18   2.9   1.6
 45000 -57.5 -71.5  290  53 27   2.5   1.4 | -56.8 -70.2  290  56 29   2.9   1.6
 40000 -60.4 -76.7  300  70 36  -2.4  -1.3 | -59.7 -75.5  290  66 34  -2.5  -1.3
 38000 -60.9 -77.6  305  74 38   3.3   1.8 | -60.5 -76.9  290  69 35   2.2   1.2
 36000 -58.8 -73.8  305  71 36   3.4   1.9 | -59.1 -74.4  300  72 37   2.3   1.3
 34000 -56.8 -70.2  305  67 34   4.8   2.6 | -57.2 -71.0  310  78 40   7.9   4.4
 32000 -51.7 -61.1  305  63 32   7.7   4.2 | -52.0 -61.6  305  76 39   8.6   4.7
 30000 -47.0 -52.6  300  59 31   8.3   4.6 | -46.9 -52.4  305  73 37   8.1   4.4
 29000 -44.5 -48.1  300  57 29   8.3   4.6 | -44.5 -48.1  300  65 33   8.1   4.4
 28000 -42.1 -43.8  300  54 28   8.3   4.6 | -42.0 -43.6  295  57 29   8.1   4.4
 27000 -39.6 -39.3  295  51 26   8.3   4.6 | -39.6 -39.3  290  50 26   8.1   4.4
 26000 -37.1 -34.8  295  47 24   8.4   4.6 | -37.1 -34.8  290  48 25   8.4   4.6
 25000 -34.6 -30.3  295  43 22   8.4   4.6 | -34.6 -30.3  295  46 24   8.4   4.6
 24000 -32.1 -25.8  295  38 20   8.5   4.7 | -32.1 -25.8  295  45 23   8.5   4.7
 23000 -29.7 -21.5  295  37 19   7.5   4.1 | -29.8 -21.6  300  44 23   7.4   4.1
 22000 -27.5 -17.5  305  36 19   7.5   4.1 | -27.6 -17.7  305  45 23   7.4   4.1
 21000 -25.3 -13.5  310  36 18   7.6   4.2 | -25.3 -13.5  310  45 23   7.3   4.0
 20000 -22.9  -9.2  315  38 19   8.1   4.4 | -23.3  -9.9  310  44 23   6.9   3.8
 19500 -21.7  -7.1  315  39 20   8.1   4.4 | -22.2  -8.0  310  44 22   6.9   3.8
 19000 -20.5  -4.9  315  40 21   8.1   4.4 | -21.2  -6.2  310  43 22   6.9   3.8
 18500 -19.2  -2.6  320  41 21   8.1   4.4 | -20.1  -4.2  315  43 22   7.0   3.8
 18000 -18.1  -0.6  320  43 22   7.5   4.1 | -19.1  -2.4  315  43 22   7.0   3.8
 17500 -17.0   1.4  320  44 23   7.5   4.1 | -18.1  -0.6  315  43 22   7.0   3.8
 17000 -15.9   3.4  320  45 23   7.1   3.9 | -16.5   2.3  315  43 22   7.2   3.9
 16500 -14.8   5.4  320  45 23   7.0   3.8 | -15.4   4.3  315  43 22   7.2   4.0
 16000 -13.3   8.1  320  45 23   6.8   3.7 | -14.4   6.1  315  43 22   6.8   3.7
 15500 -12.3   9.9  320  45 23   6.8   3.7 | -13.4   7.9  315  43 22   6.8   3.7
 15000 -11.3  11.7  320  46 24   6.6   3.6 | -12.4   9.7  315  43 22   6.7   3.6
 14500 -10.3  13.5  320  46 24   6.5   3.6 | -11.4  11.5  315  43 22   6.6   3.6
 14000  -9.3  15.3  315  46 24   6.2   3.4 | -10.4  13.3  315  44 22   6.7   3.7
 13500  -8.5  16.7  315  46 23   5.8   3.2 |  -9.4  15.1  315  44 23   6.8   3.7
 13000  -7.6  18.3  315  45 23   5.6   3.1 |  -8.4  16.9  315  44 23   6.4   3.5
 12500  -6.8  19.8  315  45 23   5.1   2.8 |  -7.6  18.3  315  44 23   5.7   3.1
 12000  -6.1  21.0  310  46 23   5.0   2.7 |  -6.7  19.9  315  43 22   5.9   3.2
 11500  -5.4  22.3  310  45 23   4.3   2.4 |  -5.8  21.6  315  43 22   6.3   3.5
 11000  -4.8  23.4  310  44 23   4.2   2.3 |  -4.9  23.2  310  43 22   5.9   3.3
 10500  -4.2  24.4  305  43 22   3.6   2.0 |  -4.1  24.6  310  42 21   5.0   2.8
 10250  -4.0  24.8  305  43 22   3.3   1.8 |  -3.7  25.3  310  41 21   5.6   3.1
 10000  -3.7  25.3  305  42 22   4.4   2.4 |  -3.3  26.1  310  40 21   3.6   2.0
  9750  -3.4  25.9  305  40 21   4.3   2.3 |  -3.1  26.4  310  39 20   3.6   2.0
  9500  -3.1  26.4  305  38 20   3.2   1.7 |  -2.8  27.0  310  37 19   5.7   3.1
  9250  -2.9  26.8  300  37 19   3.4   1.9 |  -2.4  27.7  305  36 18   5.0   2.8
  9000  -2.6  27.3  300  35 18   3.3   1.8 |  -2.0  28.4  305  34 18   5.3   2.9
  8750  -2.4  27.7  300  32 16   4.2   2.3 |  -1.6  29.1  305  32 16   6.1   3.3
  8500  -2.0  28.4  300  29 15   4.7   2.6 |  -1.1  30.0  305  30 15   6.6   3.6
  8250  -1.7  28.9  300  26 14   4.8   2.6 |  -0.6  30.9  305  28 14   6.3   3.5
  8000  -1.3  29.7  295  23 12   5.3   2.9 |  -0.2  31.6  305  25 13   6.2   3.4
  7750  -0.9  30.4  295  20 10   5.7   3.1 |   0.3  32.5  305  23 12   5.7   3.2
  7500  -0.5  31.1  295  17  9   5.5   3.0 |   0.7  33.3  305  20 10   5.5   3.0
  7250  -0.0  32.0  290  14  7   6.8   3.7 |   1.1  34.0  300  18  9   4.9   2.7
  7000   0.6  33.1  285  12  6   8.0   4.4 |   1.4  34.5  300  14  7   4.2   2.3
  6750   1.2  34.2  280   9  5   7.9   4.3 |   1.8  35.2  295  11  6   5.1   2.8
  6500   1.7  35.1  265   8  4   6.8   3.7 |   2.2  36.0  280   9  4   5.7   3.1
  6250   2.1  35.8  250   7  3   4.5   2.4 |   2.6  36.7  265   7  4   5.4   2.9
  6000   2.4  36.3  235   7  3   4.7   2.6 |   3.0  37.4  245   6  3   5.9   3.2
  5750   2.8  37.0  220   7  4   4.1   2.3 |   3.5  38.3  225   6  3   5.8   3.2
  5500   2.6  36.7  215   6  3 -12.5  -6.9 |   3.7  38.7  215   6  3  -0.5  -0.3

           02/02/2015 at 1400 MST          |       02/02/2015 at 1700 MST
                                           |
K index... +13.5  LI... +3.5               | K index... +13.4  LI... +3.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -59.8 -75.6  275  38 20   2.5   1.4 | -59.3 -74.7  275  42 22   2.0   1.1
 45000 -56.0 -68.8  280  63 33   2.3   1.3 | -56.1 -69.0  285  64 33   1.9   1.0
 40000 -60.8 -77.4  280  67 35  -3.8  -2.1 | -58.9 -74.0  290  66 34  -2.3  -1.2
 38000 -62.0 -79.6  280  69 35   3.3   1.8 | -59.6 -75.3  290  65 34   2.2   1.2
 36000 -59.9 -75.8  285  72 37   3.5   1.9 | -58.3 -72.9  295  65 33   2.3   1.2
 34000 -57.9 -72.2  295  76 39   4.6   2.5 | -56.9 -70.4  300  65 34   2.2   1.2
 32000 -52.2 -62.0  290  75 39   8.6   4.7 | -53.1 -63.6  305  62 32   5.9   3.3
 30000 -47.1 -52.8  290  74 38   8.1   4.4 | -49.5 -57.1  310  59 31   7.2   3.9
 29000 -44.7 -48.5  290  72 37   8.0   4.4 | -47.3 -53.1  310  58 30   7.3   4.0
 28000 -42.3 -44.1  295  70 36   8.0   4.4 | -45.1 -49.2  310  56 29   7.3   4.0
 27000 -39.9 -39.8  295  69 35   8.0   4.4 | -42.9 -45.2  310  55 28   7.1   3.9
 26000 -37.4 -35.3  295  63 32   8.5   4.7 | -40.4 -40.7  310  53 27   9.0   4.9
 25000 -34.8 -30.6  290  56 29   8.5   4.7 | -37.7 -35.9  310  50 26   8.9   4.9
 24000 -32.3 -26.1  290  50 26   8.6   4.7 | -35.0 -31.0  310  48 25   8.9   4.9
 23000 -29.9 -21.8  290  49 25   7.8   4.3 | -32.3 -26.1  310  47 24   9.2   5.0
 22000 -27.5 -17.5  295  51 26   7.8   4.3 | -29.6 -21.3  310  47 24   9.2   5.0
 21000 -25.2 -13.4  300  53 28   7.5   4.1 | -26.8 -16.2  310  46 24   8.8   4.9
 20000 -23.2  -9.8  305  53 27   6.4   3.5 | -24.4 -11.9  315  47 24   7.9   4.3
 19500 -22.3  -8.1  305  52 27   6.4   3.5 | -23.2  -9.8  315  47 24   7.9   4.3
 19000 -21.3  -6.3  305  51 26   6.4   3.5 | -22.1  -7.8  320  47 24   7.9   4.3
 18500 -20.4  -4.7  305  51 26   6.4   3.5 | -20.9  -5.6  320  47 24   7.8   4.3
 18000 -19.5  -3.1  310  50 26   5.7   3.1 | -19.8  -3.6  320  46 24   6.7   3.7
 17500 -18.6  -1.5  310  49 25   5.8   3.2 | -18.8  -1.8  325  43 22   6.8   3.7
 17000 -17.8  -0.0  310  48 25   6.0   3.3 | -17.8  -0.0  325  42 21   6.5   3.6
 16500 -16.9   1.6  310  49 25   6.1   3.3 | -16.9   1.6  325  42 22   6.4   3.5
 16000 -15.5   4.1  310  49 25   5.8   3.2 | -15.5   4.1  325  42 22   5.9   3.3
 15500 -14.7   5.5  310  48 25   5.8   3.2 | -14.6   5.7  325  42 22   6.0   3.3
 15000 -13.8   7.2  310  48 25   6.3   3.4 | -13.7   7.3  325  42 22   6.6   3.6
 14500 -12.9   8.8  310  47 24   6.5   3.6 | -12.7   9.1  325  42 22   6.7   3.7
 14000 -11.9  10.6  310  47 24   6.7   3.7 | -11.7  10.9  325  42 22   6.6   3.6
 13500 -10.9  12.4  310  46 24   6.9   3.8 | -10.8  12.6  320  41 21   6.5   3.6
 13000  -9.9  14.2  310  45 23   6.9   3.8 |  -9.8  14.4  320  41 21   6.5   3.6
 12500  -8.9  16.0  310  44 23   6.9   3.8 |  -8.9  16.0  320  38 20   6.6   3.6
 12000  -7.9  17.8  310  42 22   7.0   3.8 |  -7.9  17.8  320  35 18   7.1   3.9
 11500  -6.8  19.8  310  40 21   7.2   4.0 |  -6.8  19.8  315  33 17   7.8   4.3
 11000  -5.8  21.6  305  39 20   7.3   4.0 |  -5.6  21.9  315  31 16   7.7   4.2
 10500  -4.7  23.5  305  35 18   7.9   4.3 |  -4.5  23.9  315  29 15   7.9   4.4
 10250  -4.1  24.6  305  34 17   4.9   2.7 |  -4.0  24.8  315  28 14   5.1   2.8
 10000  -3.9  25.0  305  33 17   5.8   3.2 |  -3.7  25.3  315  27 14   6.0   3.3
  9750  -3.2  26.2  305  31 16   9.3   5.1 |  -3.1  26.4  310  26 13   9.6   5.3
  9500  -2.6  27.3  305  29 15   8.5   4.6 |  -2.4  27.7  310  24 12   8.7   4.8
  9250  -2.0  28.4  305  27 14   8.4   4.6 |  -1.7  28.9  310  23 12   8.7   4.8
  9000  -1.4  29.5  305  26 13   7.2   4.0 |  -1.1  30.0  310  22 11   8.0   4.4
  8750  -0.8  30.6  305  24 12   7.4   4.1 |  -0.5  31.1  310  20 11   8.3   4.5
  8500  -0.3  31.5  305  22 11   8.1   4.4 |   0.1  32.2  310  19 10   8.4   4.6
  8250   0.3  32.5  305  20 10   7.6   4.2 |   0.7  33.3  310  18  9   8.5   4.7
  8000   0.9  33.6  305  18  9   7.2   3.9 |   1.4  34.5  305  16  8   8.7   4.8
  7750   1.4  34.5  300  16  8   6.7   3.7 |   2.0  35.6  305  15  8   8.3   4.6
  7500   1.9  35.4  300  15  8   6.4   3.5 |   2.6  36.7  305  14  7   8.1   4.4
  7250   2.3  36.1  300  13  7   6.0   3.3 |   3.2  37.8  300  13  6   7.5   4.1
  7000   2.8  37.0  290  11  6   5.7   3.1 |   3.7  38.7  290  11  6   7.2   3.9
  6750   3.2  37.8  280   9  5   5.4   2.9 |   4.2  39.6  280  10  5   6.8   3.7
  6500   3.6  38.5  270   8  4   5.2   2.8 |   4.7  40.5  265   9  5   6.5   3.6
  6250   4.0  39.2  250   7  4   5.5   3.0 |   5.2  41.4  250   9  5   6.4   3.5
  6000   4.4  39.9  230   8  4   5.6   3.1 |   5.7  42.3  240   9  5   7.4   4.0
  5750   4.8  40.6  210   9  4   6.3   3.4 |   6.2  43.2  225  10  5   5.3   2.9
  5500   5.3  41.5  200   8  4   6.3   3.5 |   6.2  43.2  215   9  4  -5.7  -3.1
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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