Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 161242
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0542 MST Tuesday, December 16, 2014

This forecast is for Tuesday, December 16, 2014:

If the trigger temperature of 51.4 F/10.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6824 ft MSL (1539 ft AGL)

Forecast maximum temperature................... 38.0 F/3.8 C
Time of trigger temperature.................... None
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................. 6337 ft MSL (1052 ft AGL)
Thermal soaring outlook for Wednesday 12/17.... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Becoming fair by 1200 MST
Height of stable layer (12-18K ft MSL)......... 14904 ft MSL (9619 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 15397 ft MSL (10112 ft AGL)
Wave soaring outlook for Wednesday 12/17....... Poor

Remarks...

Sunrise/Sunset.................... 07:14:06 / 16:36:22 MST
Total possible sunshine........... 9 hr 22 min 16 sec (562 min 16 sec)
Altitude of sun at 11:55:16 MST... 26.97 degrees

Upper air data from rawinsonde observation taken on 12/16/2014 at 0500 MST

Freezing level.................. 7375 ft MSL (2090 ft AGL)
Additional freezing level....... 7870 ft MSL (2585 ft AGL)
Convective condensation level... 21182 ft MSL (15897 ft AGL)
Lifted condensation level....... 13650 ft MSL (8365 ft AGL)
Lifted index.................... +15.3
K index......................... -14.3

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  -61.4 -78.5   255   41   21   4.2   2.3   97.2 206.9    53.6      M    M
 45000  -53.4 -64.1   265   47   24  -3.5  -1.9   86.0 186.8    50.6      M    M
 40000  -52.9 -63.2   265   67   34   2.7   1.5   63.7 146.6    39.5      M    M
 38000  -55.2 -67.4   270   69   35  -2.8  -1.5   51.4 124.5    32.3      M    M
 36000  -54.4 -65.9   270   92   47   1.3   0.7   43.9 111.1    28.0      M    M
 34000  -52.9 -63.2   265  102   52  -2.5  -1.4   36.6  97.8    23.6      M    M
 32000  -49.8 -57.6   265   92   47   7.2   4.0   32.7  90.8    21.4      M    M
 30000  -46.1 -51.0   275   72   37   6.4   3.5   29.9  85.7    19.9      M    M
 29000  -43.6 -46.5   270   62   32   8.2   4.5   29.2  84.6    19.7      M    M
 28000  -41.2 -42.2   270   60   31   8.6   4.7   28.6  83.5    19.4      M    M
 27000  -38.5 -37.3   270   58   30   8.9   4.9   28.2  82.7    19.3      M    M
 26000  -35.8 -32.4   275   57   29   8.9   4.9   27.9  82.2    19.3      M    M
 25000  -33.4 -28.1   275   55   28   5.4   3.0   27.3  81.2    19.1      M    M
 24000  -31.7 -25.1   265   43   22   5.8   3.2   25.8  78.4    18.1      M    M
 23000  -29.6 -21.3   270   36   19   9.9   5.4   24.8  76.6    17.5      M    M
 22000  -27.1 -16.8   275   34   18   7.1   3.9   24.3  75.7    17.3      M    M
 21000  -24.6 -12.3   275   33   17   7.7   4.2   23.8  74.8    17.1      M    M
 20000  -22.5  -8.5   280   31   16   8.5   4.7   22.8  73.1    16.4      M    M
 19500  -21.1  -6.0   280   31   16   9.1   5.0   22.7  72.9    16.4      M    M
 19000  -19.7  -3.5   280   32   16   9.2   5.0   22.6  72.8    16.4      M    M
 18500  -18.3  -0.9   280   32   16   8.8   4.8   22.6  72.7    16.5      M    M
 18000  -17.1   1.2   280   32   17   8.0   4.4   22.3  72.1    16.3      M    M
 17500  -15.9   3.4   280   33   17   8.2   4.5   22.0  71.6    16.1      M    M
 17000  -14.1   6.6   280   33   17   8.3   4.5   21.6  70.9    15.9      M    M
 16500  -12.8   9.0   280   34   17   8.3   4.5   21.4  70.5    15.8      M    M
 16000  -11.6  11.1   280   34   18   8.3   4.6   21.1  70.0    15.7      M    M
 15500  -10.3  13.5   285   35   18   9.1   5.0   20.9  69.6    15.6      M    M
 15000   -9.7  14.5   290   36   18  -0.4  -0.2   20.0  67.9    14.8      M    M
 14500   -9.6  14.7   290   37   19   0.4   0.2   18.4  65.2    13.5      M    M
 14000   -9.3  15.3   295   37   19   3.8   2.1   17.1  62.8    12.4      M    M
 13500   -8.6  16.5   295   30   15   4.6   2.5   16.2  61.2    11.7      M    M
 13000   -7.9  17.8   295   23   12   5.0   2.7   15.4  59.8    11.0      M    M
 12500   -6.9  19.6   295   15    8   7.2   3.9   14.9  58.8    10.6      M    M
 12000   -5.9  21.4   295    9    5   7.0   3.9   14.5  58.0    10.3      M    M
 11500   -4.8  23.4   285   11    6   7.0   3.9   14.0  57.2     9.9      M    M
 11000   -3.8  25.2   280   13    7   7.0   3.9   13.5  56.4     9.5      M    M
 10500   -2.7  27.1   275   15    8   7.1   3.9   13.1  55.6     9.1      M    M
 10250   -2.2  28.0   275   16    8   7.0   3.8   12.9  55.3     9.0      M    M
 10000   -1.6  29.1   275   16    8   9.3   5.1   12.8  55.0     8.9      M    M
  9750   -1.0  30.2   275   14    7   4.8   2.6   12.7  54.8     8.8      M    M
  9500   -1.0  30.2   275   12    6  -4.9  -2.7   11.9  53.3     8.1      M    M
  9250   -1.5  29.3   275   10    5  -5.9  -3.3   10.6  51.1     6.9      M    M
  9000   -1.7  28.9   275    8    4   1.6   0.9    9.6  49.3     5.9      M    M
  8750   -1.3  29.7   260    6    3   6.1   3.3    9.3  48.7     5.6      M    M
  8500   -0.9  30.4   240    4    2   4.8   2.7    8.9  48.0     5.3      M    M
  8250   -0.6  30.9   200    4    2   5.4   3.0    8.5  47.4     4.9      M    M
  8000   -0.2  31.6   170    5    3   4.4   2.4    8.2  46.7     4.6      M    M
  7750    0.2  32.4   185    7    3   7.8   4.3    7.8  46.1     4.2      M    M
  7500    0.6  33.1   190    9    4  -4.6  -2.5    7.5  45.5     3.9      M    M
  7250   -0.5  31.1   195   11    6 -13.5  -7.4    5.7  42.3     2.1      M    M
  7000   -1.1  30.0   200   13    7  -3.8  -2.1    4.4  39.9     0.8      M    M
  6750   -1.4  29.5   200   12    6  -4.0  -2.2    3.4  38.1    -0.2    203  1.0
  6500   -2.0  28.4   205   11    6 -12.2  -6.7    2.1  35.7    -1.6    214  1.1
  6250   -3.2  26.2   205   10    5 -15.5  -8.5    0.1  32.3    -3.5    242  1.2
  6000   -4.0  24.8   210    9    5  -6.5  -3.6   -1.5  29.4    -5.1    260  1.3
  5750   -4.3  24.3   210    7    3  -3.9  -2.2   -2.5  27.5    -6.1    262  1.3
  5500   -5.0  23.0   205    4    2 -15.1  -8.3   -3.9  25.0    -7.6    274  1.4

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

           12/16/2014 at 0800 MST          |       12/16/2014 at 1100 MST
                                           |
K index... +5.5  LI... +3.9                | K index... +15.4  LI... +3.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.2
                                           |
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 -60.1 -76.2  245  40 20   3.0   1.6 | -60.5 -76.9  245  37 19   2.6   1.4
 45000 -55.7 -68.3  250  53 27   1.1   0.6 | -56.5 -69.7  240  54 28   1.2   0.7
 40000 -55.8 -68.4  260  65 34  -0.1  -0.0 | -55.7 -68.3  250  70 36   0.5   0.3
 38000 -54.7 -66.5  265  71 36   3.6   2.0 | -54.7 -66.5  250  75 39   3.0   1.6
 36000 -52.6 -62.7  265  76 39   3.6   2.0 | -52.9 -63.2  250  80 41   3.0   1.6
 34000 -50.2 -58.4  265  79 41   3.2   1.8 | -51.0 -59.8  250  83 43   4.2   2.3
 32000 -48.3 -54.9  265  72 37   3.2   1.8 | -48.2 -54.8  250  79 41   4.2   2.3
 30000 -45.6 -50.1  265  65 33   8.2   4.5 | -45.2 -49.4  250  73 38   7.6   4.2
 29000 -43.2 -45.8  265  61 31   8.2   4.5 | -42.9 -45.2  250  65 34   7.7   4.2
 28000 -40.7 -41.3  265  57 29   8.3   4.5 | -40.6 -41.1  250  58 30   7.7   4.2
 27000 -38.2 -36.8  265  52 27   8.3   4.5 | -38.3 -36.9  245  50 26   7.9   4.3
 26000 -35.8 -32.4  265  49 25   8.3   4.5 | -35.9 -32.6  245  46 24   8.1   4.4
 25000 -33.3 -27.9  265  45 23   8.3   4.5 | -33.4 -28.1  245  43 22   8.1   4.5
 24000 -30.8 -23.4  265  41 21   8.0   4.4 | -31.0 -23.8  245  39 20   8.1   4.4
 23000 -28.6 -19.5  265  38 20   7.1   3.9 | -28.7 -19.7  245  38 19   7.8   4.3
 22000 -26.5 -15.7  270  35 18   7.1   3.9 | -26.4 -15.5  245  36 19   7.8   4.3
 21000 -24.4 -11.9  270  32 17   7.4   4.0 | -24.1 -11.4  250  35 18   7.6   4.2
 20000 -22.2  -8.0  270  31 16   7.5   4.1 | -21.8  -7.2  245  32 17   7.5   4.1
 19500 -21.0  -5.8  265  30 15   7.5   4.1 | -20.7  -5.3  245  31 16   7.5   4.1
 19000 -19.9  -3.8  265  29 15   7.5   4.1 | -19.6  -3.3  245  29 15   7.5   4.1
 18500 -18.8  -1.8  265  28 15   7.6   4.2 | -18.5  -1.3  245  28 14   7.5   4.1
 18000 -17.7   0.1  265  28 14   7.7   4.2 | -17.4   0.7  245  27 14   7.4   4.1
 17500 -16.5   2.3  260  28 14   7.7   4.2 | -16.3   2.7  245  26 13   7.5   4.1
 17000 -15.3   4.5  260  27 14   8.1   4.4 | -15.3   4.5  240  25 13   6.7   3.7
 16500 -13.5   7.7  265  25 13   8.0   4.4 | -14.3   6.3  240  24 12   6.8   3.7
 16000 -12.3   9.9  265  24 13   7.9   4.3 | -12.8   9.0  240  22 11   7.0   3.8
 15500 -11.2  11.8  270  24 12   7.9   4.3 | -11.8  10.8  240  21 11   7.0   3.8
 15000 -10.0  14.0  270  23 12   7.4   4.1 | -10.8  12.6  240  20 10   6.4   3.5
 14500  -8.9  16.0  275  22 12   7.4   4.1 |  -9.8  14.4  240  20 10   6.4   3.5
 14000  -7.8  18.0  280  22 11   7.7   4.3 |  -8.9  16.0  240  19 10   6.5   3.5
 13500  -6.7  19.9  280  21 11   7.8   4.3 |  -7.9  17.8  240  18  9   6.5   3.5
 13000  -5.5  22.1  280  20 11   7.0   3.8 |  -7.0  19.4  240  17  9   7.1   3.9
 12500  -4.5  23.9  280  19 10   6.6   3.6 |  -5.8  21.6  240  16  8   7.5   4.1
 12000  -3.5  25.7  280  18  9   6.2   3.4 |  -4.7  23.5  240  15  8   8.2   4.5
 11500  -2.6  27.3  275  16  8   6.0   3.3 |  -3.3  26.1  235  14  7   8.6   4.7
 11000  -1.8  28.8  275  14  7   5.0   2.7 |  -2.0  28.4  235  13  7   7.5   4.1
 10500  -1.1  30.0  270  13  6   4.7   2.6 |  -1.0  30.2  235  12  6   7.2   3.9
 10250  -0.8  30.6  265  12  6   3.1   1.7 |  -0.4  31.3  235  11  6   5.5   3.0
 10000  -0.6  30.9  260  11  6   1.9   1.0 |  -0.1  31.8  235  10  5   3.2   1.7
  9750  -0.4  31.3  260  10  5   3.8   2.1 |   0.1  32.2  235  10  5   4.0   2.2
  9500  -0.0  32.0  250  10  5   4.9   2.7 |   0.5  32.9  230   9  5   5.1   2.8
  9250   0.3  32.5  245   9  5   3.9   2.1 |   0.9  33.6  230   8  4   3.6   1.9
  9000   0.6  33.1  240   8  4   2.5   1.4 |   1.0  33.8  230   7  4   1.0   0.5
  8750   0.7  33.3  235   8  4   1.6   0.9 |   1.1  34.0  225   6  3   0.9   0.5
  8500   0.8  33.4  230   7  4   1.8   1.0 |   1.2  34.2  220   5  3   2.0   1.1
  8250   1.0  33.8  225   6  3   0.4   0.2 |   1.3  34.3  220   4  2  -0.0  -0.0
  8000   0.9  33.6  220   5  3  -0.7  -0.4 |   1.2  34.2  220   3  2  -2.1  -1.1
  7750   0.8  33.4  220   4  2  -1.3  -0.7 |   1.1  34.0  220   2  1  -1.1  -0.6
  7500   0.6  33.1  220   4  2  -3.5  -1.9 |   1.0  33.8  225   2  1  -2.3  -1.3
  7250   0.3  32.5  220   3  2  -5.5  -3.0 |   0.7  33.3  240   1  1  -6.4  -3.5
  7000  -0.2  31.6  225   2  1  -6.9  -3.8 |   0.1  32.2  275   1  1  -8.3  -4.5
  6750  -0.7  30.7  235   2  1  -5.1  -2.8 |  -0.5  31.1  300   2  1  -7.2  -3.9
  6500  -1.2  29.8  245   1  1  -8.5  -4.7 |  -1.1  30.0  310   2  1  -8.4  -4.6
  6250  -2.1  28.2  265   2  1 -12.6  -6.9 |  -1.9  28.6  315   3  1  -9.4  -5.2
  6000  -3.0  26.6  280   2  1 -11.3  -6.2 |  -2.6  27.3  320   3  1 -10.4  -5.7
  5750  -3.9  25.0  285   3  1 -12.4  -6.8 |  -3.4  25.9  325   3  1  -6.5  -3.6
  5500  -4.9  23.2  265   2  1 -14.1  -7.7 |  -3.4  25.9  330   3  1   8.4   4.6

           12/16/2014 at 1400 MST          |       12/16/2014 at 1700 MST
                                           |
K index... +21.3  LI... +1.0               | K index... +21.8  LI... +1.1
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 -59.1 -74.4  240  37 19   2.6   1.5 | -59.3 -74.7  240  41 21   3.2   1.8
 45000 -55.0 -67.0  240  57 30   1.2   0.6 | -54.2 -65.6  245  62 32   1.4   0.8
 40000 -55.0 -67.0  245  71 37  -0.0  -0.0 | -54.9 -66.8  240  71 36  -0.5  -0.3
 38000 -54.7 -66.5  245  77 39   1.3   0.7 | -54.6 -66.3  240  74 38   1.8   1.0
 36000 -53.9 -65.0  245  82 42   1.2   0.7 | -53.6 -64.5  240  76 39   1.8   1.0
 34000 -53.0 -63.4  245  86 44   4.9   2.7 | -52.4 -62.3  240  77 40   3.8   2.1
 32000 -49.4 -56.9  240  71 37   5.3   2.9 | -49.8 -57.6  240  69 35   4.4   2.4
 30000 -45.7 -50.3  240  59 30   9.4   5.2 | -46.3 -51.3  240  59 31   9.1   5.0
 29000 -42.8 -45.0  240  55 28   9.5   5.2 | -43.6 -46.5  235  54 28   9.0   4.9
 28000 -40.0 -40.0  235  51 26   9.5   5.2 | -40.9 -41.6  235  49 25   9.0   4.9
 27000 -37.2 -35.0  235  46 24   8.9   4.9 | -38.2 -36.8  235  44 23   8.7   4.8
 26000 -34.7 -30.5  235  45 23   8.3   4.6 | -35.8 -32.4  235  44 22   8.3   4.5
 25000 -32.2 -26.0  240  45 23   8.3   4.6 | -33.3 -27.9  235  43 22   8.3   4.5
 24000 -29.7 -21.5  240  44 23   8.0   4.4 | -30.8 -23.4  240  43 22   8.3   4.5
 23000 -27.8 -18.0  240  40 21   6.1   3.3 | -28.5 -19.3  240  42 22   7.8   4.3
 22000 -26.0 -14.8  240  36 19   6.1   3.4 | -26.2 -15.2  245  42 21   7.8   4.3
 21000 -24.2 -11.6  235  32 16   6.9   3.8 | -23.8 -10.8  245  41 21   6.8   3.7
 20000 -21.9  -7.4  235  27 14   7.5   4.1 | -22.1  -7.8  250  38 19   5.8   3.2
 19500 -20.8  -5.4  235  25 13   7.6   4.1 | -21.3  -6.3  250  36 19   5.8   3.2
 19000 -19.7  -3.5  230  23 12   7.6   4.1 | -20.4  -4.7  255  34 18   5.8   3.2
 18500 -18.6  -1.5  230  21 11   7.3   4.0 | -19.5  -3.1  255  33 17   6.1   3.3
 18000 -17.5   0.5  235  20 10   6.9   3.8 | -18.6  -1.5  255  30 16   6.7   3.7
 17500 -16.5   2.3  240  20 10   6.9   3.8 | -17.6   0.3  255  27 14   6.7   3.7
 17000 -15.5   4.1  240  20 10   6.9   3.8 | -16.6   2.1  255  25 13   6.5   3.6
 16500 -14.5   5.9  245  20 10   6.9   3.8 | -15.7   3.7  250  23 12   6.6   3.6
 16000 -12.9   8.8  250  21 11   7.1   3.9 | -14.7   5.5  250  21 11   7.3   4.0
 15500 -11.9  10.6  250  23 12   7.1   3.9 | -13.5   7.7  255  19 10   7.8   4.3
 15000 -10.9  12.4  255  23 12   6.8   3.7 | -11.9  10.6  260  16  8   6.9   3.8
 14500  -9.9  14.2  255  23 12   6.8   3.7 | -10.9  12.4  260  14  7   6.8   3.7
 14000  -8.9  16.0  255  23 12   6.8   3.7 |  -9.9  14.2  260  12  6   6.4   3.5
 13500  -7.9  17.8  255  22 11   6.8   3.7 |  -9.0  15.8  255   9  5   6.3   3.4
 13000  -6.9  19.6  255  21 11   6.7   3.7 |  -8.1  17.4  250   7  3   6.4   3.5
 12500  -6.0  21.2  255  20 10   6.6   3.6 |  -7.1  19.2  260   6  3   6.6   3.6
 12000  -5.0  23.0  255  18 10   6.4   3.5 |  -6.2  20.8  270   6  3   6.5   3.6
 11500  -4.1  24.6  255  17  9   6.1   3.3 |  -5.2  22.6  280   6  3   6.3   3.5
 11000  -3.2  26.2  255  16  8   5.3   2.9 |  -4.3  24.3  285   6  3   6.1   3.3
 10500  -2.6  27.3  250  14  7   4.8   2.6 |  -3.4  25.9  290   6  3   6.0   3.3
 10250  -2.3  27.9  245  14  7   3.5   1.9 |  -3.0  26.6  295   6  3   4.6   2.5
 10000  -2.1  28.2  245  13  7   1.9   1.1 |  -2.7  27.1  295   6  3   4.2   2.3
  9750  -1.9  28.6  240  12  6   3.5   1.9 |  -2.3  27.9  295   6  3   6.6   3.6
  9500  -1.5  29.3  240  10  5   4.8   2.6 |  -1.8  28.8  295   5  3   7.5   4.1
  9250  -1.1  30.0  235   9  5   4.4   2.4 |  -1.2  29.8  295   5  3   6.6   3.6
  9000  -0.8  30.6  230   8  4   4.7   2.6 |  -0.8  30.6  290   5  2   4.6   2.5
  8750  -0.4  31.3  225   6  3   5.7   3.1 |  -0.4  31.3  285   4  2   4.7   2.6
  8500   0.2  32.4  210   5  2   6.9   3.8 |   0.0  32.0  280   4  2   6.0   3.3
  8250   0.7  33.3  195   3  2   4.7   2.6 |   0.5  32.9  270   3  2   4.5   2.5
  8000   1.0  33.8  165   2  1   2.5   1.4 |   0.8  33.4  260   3  1   3.2   1.8
  7750   1.2  34.2  120   2  1   1.1   0.6 |   1.0  33.8  245   2  1   2.2   1.2
  7500   1.2  34.2  090   3  1  -1.2  -0.7 |   1.2  34.2  225   1  1   0.9   0.5
  7250   1.0  33.8  070   3  2  -6.3  -3.5 |   1.2  34.2  175   1  0  -2.5  -1.4
  7000   0.3  32.5  065   2  1  -9.2  -5.1 |   0.9  33.6  135   1  1  -4.2  -2.3
  6750  -0.3  31.5  050   2  1  -9.6  -5.2 |   0.6  33.1  120   2  1  -5.7  -3.1
  6500  -1.1  30.0  030   1  1  -7.6  -4.2 |   0.1  32.2  125   2  1  -6.8  -3.7
  6250  -1.5  29.3  030   1  0  -3.9  -2.1 |  -0.4  31.3  140   2  1  -4.9  -2.7
  6000  -1.9  28.6  000   0  0  -5.9  -3.3 |  -0.9  30.4  155   2  1  -5.8  -3.2
  5750  -2.3  27.9  205   1  0   0.2   0.1 |  -1.3  29.7  170   3  1  -3.7  -2.0
  5500  -1.8  28.8  000   0  0  15.2   8.3 |  -1.4  29.5  165   2  1   4.1   2.2
________________________________________________________________________________

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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