Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 311313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0613 MST Saturday, January 31, 2015

This forecast is for Saturday, January 31, 2015:

If the trigger temperature of 47.4 F/8.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8835 ft MSL (3550 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 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................. 6533 ft MSL (1247 ft AGL)
Thermal soaring outlook for Sunday 02/01....... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... 11940 ft MSL (6655 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 13665 ft MSL (8380 ft AGL)
Wave soaring outlook for Sunday 02/01.......... Fair

Remarks...

Sunrise/Sunset.................... 07:08:20 / 17:16:32 MST
Total possible sunshine........... 10 hr 8 min 12 sec (608 min 12 sec)
Altitude of sun at 12:12:48 MST... 32.97 degrees

Upper air data from rawinsonde observation taken on 01/31/2015 at 0500 MST

Freezing level.................. 6025 ft MSL (740 ft AGL)
Convective condensation level... 17505 ft MSL (12220 ft AGL)
Lifted condensation level....... 10519 ft MSL (5234 ft AGL)
Lifted index.................... +14.5
K index......................... +11.8

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  -59.6 -75.3   280   41   21   4.6   2.5   99.6 211.3    53.3      M    M
 45000  -54.6 -66.3   260   44   23  -5.8  -3.2   83.4 182.1    47.0      M    M
 40000  -58.3 -72.9   235   60   31 -21.9 -12.0   54.5 130.1    31.4      M    M
 38000  -63.2 -81.8   220   65   33   8.5   4.7   38.2 100.8    21.3      M    M
 36000  -57.6 -71.7   215   65   33   9.4   5.2   37.9 100.2    21.6      M    M
 34000  -52.2 -62.0   225   64   33   5.8   3.2   37.1  98.8    21.7      M    M
 32000  -46.9 -52.4   230   65   33   9.0   4.9   35.4  95.6    21.0      M    M
 30000  -41.4 -42.5   230   59   30   9.7   5.3   35.0  94.9    21.3      M    M
 29000  -38.5 -37.3   230   59   30   9.4   5.2   34.8  94.7    21.4      M    M
 28000  -35.7 -32.3   230   59   30   9.4   5.2   34.6  94.4    21.6      M    M
 27000  -32.9 -27.2   230   59   30   9.4   5.2   34.6  94.3    21.8      M    M
 26000  -30.2 -22.4   230   59   30   8.3   4.5   34.4  93.8    21.8      M    M
 25000  -28.8 -19.8   230   59   30   3.8   2.1   32.5  90.6    20.6      M    M
 24000  -26.3 -15.3   230   48   24   9.4   5.2   32.0  89.6    20.4      M    M
 23000  -23.6 -10.5   230   44   23   8.0   4.4   31.8  89.2    20.4      M    M
 22000  -21.2  -6.2   230   43   22   8.8   4.8   31.1  87.9    20.1      M    M
 21000  -18.8  -1.8   235   41   21   7.8   4.3   30.5  86.8    19.8      M    M
 20000  -16.5   2.3   235   39   20   8.4   4.6   29.8  85.6    19.4      M    M
 19500  -15.7   3.7   235   38   19   1.8   1.0   29.0  84.3    18.8      M    M
 19000  -15.0   5.0   230   36   19   8.5   4.7   28.2  82.8    18.2      M    M
 18500  -13.8   7.2   230   34   18   6.6   3.6   27.9  82.2    18.0      M    M
 18000  -12.7   9.1   230   31   16   3.0   1.7   27.6  81.6    17.8      M    M
 17500  -12.5   9.5   230   28   14   6.3   3.4   26.1  79.0    16.6      M    M
 17000  -11.6  11.1   235   24   12   6.4   3.5   25.5  78.0    16.2      M    M
 16500  -10.6  12.9   245   23   12   4.8   2.7   25.0  77.0    15.7      M    M
 16000  -10.1  13.8   260   26   13   5.5   3.0   23.1  73.6    14.1      M    M
 15500   -9.0  15.8   260   28   14   7.3   4.0   22.7  72.9    13.8      M    M
 15000   -7.9  17.8   260   29   15   7.5   4.1   22.3  72.2    13.6      M    M
 14500   -7.6  18.3   265   24   12  -2.6  -1.5   21.1  69.9    12.5      M    M
 14000   -7.3  18.9   275   20   10   6.2   3.4   19.9  67.7    11.5      M    M
 13500   -6.5  20.3   265   19   10   3.5   1.9   19.1  66.4    10.8      M    M
 13000   -6.2  20.8   255   18    9   2.3   1.2   17.8  64.1     9.7      M    M
 12500   -5.9  21.4   245   18    9   4.1   2.3   16.6  61.8     8.6      M    M
 12000   -6.8  19.8   235   19   10 -19.0 -10.4   14.0  57.1     6.3      M    M
 11500   -7.1  19.2   235   15    8  11.6   6.4   12.1  53.7     4.5      M    M
 11000   -5.8  21.6   230   12    6   8.9   4.9   11.9  53.4     4.4      M    M
 10500   -4.5  23.9   225    9    4   6.2   3.4   11.8  53.2     4.3      M    M
 10250   -4.2  24.4   215    7    4   1.3   0.7   11.3  52.3     3.8      M    M
 10000   -4.1  24.6   210    5    3   0.7   0.4   10.6  51.0     3.2      M    M
  9750   -4.0  24.8   215    5    3   1.6   0.9    9.9  49.8     2.6      M    M
  9500   -3.7  25.3   230    5    3   4.7   2.6    9.3  48.8     2.1      M    M
  9250   -3.4  25.9   245    5    3   2.4   1.3    8.9  48.1     1.7      M    M
  9000   -3.6  25.5   255    6    3  -6.7  -3.7    8.0  46.4     0.8      M    M
  8750   -4.2  24.4   270    5    3  -2.9  -1.6    6.7  44.0    -0.5    283  1.4
  8500   -3.9  25.0   290    5    3   6.1   3.3    6.2  43.1    -1.0    267  1.4
  8250   -3.5  25.7   305    5    3   5.9   3.2    5.9  42.6    -1.3    247  1.3
  8000   -3.1  26.4   320    6    3   6.0   3.3    5.6  42.0    -1.6    226  1.2
  7750   -2.6  27.3   335    7    3   5.9   3.2    5.3  41.5    -1.9    206  1.0
  7500   -2.2  28.0   345    8    4   6.2   3.4    5.0  41.0    -2.2    186  0.9
  7250   -1.6  29.1   355    9    4   8.3   4.6    4.8  40.6    -2.4    162  0.8
  7000   -0.9  30.4   360   10    5   9.3   5.1    4.7  40.5    -2.4    133  0.7
  6750   -0.3  31.5   005    8    4   5.5   3.0    4.6  40.2    -2.5    107  0.5
  6500   -0.1  31.8   010    7    4   1.7   0.9    4.1  39.3    -3.0     93  0.5
  6250   -0.0  32.0   020    5    3  -0.5  -0.3    3.4  38.1    -3.7     84  0.4
  6000   -0.0  32.0   035    4    2   4.3   2.4    2.7  36.9    -4.4     76  0.4
  5750    0.6  33.1   035    3    1  10.2   5.6    2.6  36.7    -4.6     50  0.3
  5500    1.2  34.2   035    1    1   5.4   3.0    2.5  36.5    -4.7     24  0.1

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

           01/31/2015 at 0800 MST          |       01/31/2015 at 1100 MST
                                           |
K index... +13.2  LI... +5.8               | K index... +16.0  LI... +4.5
CAPE... 0.0  CIN... -1.0                   | 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 -59.0 -74.2  270  34 18   3.1   1.7 | -58.9 -74.0  260  36 18   4.0   2.2
 45000 -54.4 -65.9  260  47 24   1.2   0.6 | -52.9 -63.2  255  48 25   2.0   1.1
 40000 -56.3 -69.3  235  53 27  -1.3  -0.7 | -53.6 -64.5  240  53 27  -0.5  -0.2
 38000 -56.4 -69.5  230  55 28   1.4   0.8 | -54.0 -65.2  235  56 29  -0.9  -0.5
 36000 -55.6 -68.1  230  55 29   1.4   0.8 | -54.5 -66.1  225  59 31  -0.9  -0.5
 34000 -54.4 -65.9  225  56 29   7.9   4.3 | -54.3 -65.7  220  64 33   8.6   4.7
 32000 -48.8 -55.8  225  57 30   8.3   4.6 | -49.5 -57.1  220  69 36   7.9   4.3
 30000 -43.6 -46.5  225  58 30   9.3   5.1 | -44.6 -48.3  220  71 37   9.3   5.1
 29000 -40.8 -41.4  230  58 30   9.4   5.1 | -41.8 -43.2  225  66 34   9.3   5.1
 28000 -38.0 -36.4  230  58 30   9.4   5.1 | -39.1 -38.4  225  62 32   9.3   5.1
 27000 -35.2 -31.4  230  58 30   9.2   5.1 | -36.3 -33.3  230  57 29   9.3   5.1
 26000 -32.5 -26.5  230  54 28   9.0   5.0 | -33.5 -28.3  230  54 28   9.4   5.2
 25000 -29.8 -21.6  230  50 26   9.0   5.0 | -30.6 -23.1  235  50 26   9.4   5.2
 24000 -27.1 -16.8  230  46 23   9.0   5.0 | -27.8 -18.0  235  47 24   9.6   5.3
 23000 -24.8 -12.6  230  39 20   7.3   4.0 | -25.4 -13.7  235  41 21   7.6   4.2
 22000 -22.7  -8.9  230  33 17   7.4   4.0 | -23.2  -9.8  240  35 18   7.7   4.2
 21000 -20.5  -4.9  225  26 13   7.2   4.0 | -20.9  -5.6  240  28 14   7.4   4.0
 20000 -18.4  -1.1  235  25 13   6.9   3.8 | -19.0  -2.2  245  26 13   6.2   3.4
 19500 -17.4   0.7  235  25 13   6.9   3.8 | -18.1  -0.6  245  25 13   6.3   3.4
 19000 -16.4   2.5  240  25 13   7.0   3.8 | -17.2   1.0  250  24 13   6.3   3.4
 18500 -15.4   4.3  245  25 13   7.0   3.8 | -16.3   2.7  255  24 12   6.2   3.4
 18000 -14.4   6.1  245  25 13   6.4   3.5 | -15.3   4.5  255  23 12   7.1   3.9
 17500 -13.5   7.7  250  24 12   6.4   3.5 | -14.3   6.3  260  22 11   7.0   3.8
 17000 -12.5   9.5  255  23 12   6.2   3.4 | -13.3   8.1  265  21 11   5.8   3.2
 16500 -11.6  11.1  260  22 11   6.2   3.4 | -12.2  10.0  275  20 10   5.0   2.8
 16000 -10.3  13.5  270  21 11   5.9   3.2 | -11.4  11.5  280  20 10   5.8   3.2
 15500  -9.4  15.1  275  21 11   5.8   3.2 | -10.5  13.1  285  19 10   6.0   3.3
 15000  -8.6  16.5  280  20 11   5.6   3.1 |  -9.6  14.7  290  19 10   5.8   3.2
 14500  -7.8  18.0  285  20 10   5.4   2.9 |  -8.8  16.2  295  19 10   5.5   3.0
 14000  -7.0  19.4  290  19 10   5.0   2.8 |  -8.0  17.6  300  18  9   5.4   2.9
 13500  -6.4  20.5  290  18  9   3.8   2.1 |  -7.3  18.9  300  18  9   4.9   2.7
 13000  -5.8  21.6  295  17  9   3.8   2.1 |  -6.6  20.1  305  17  9   4.9   2.7
 12500  -5.4  22.3  290  15  8   2.5   1.4 |  -6.0  21.2  305  16  8   3.6   2.0
 12000  -5.0  23.0  290  13  7   2.6   1.4 |  -5.4  22.3  310  15  8   3.7   2.1
 11500  -4.7  23.5  285  11  6   2.0   1.1 |  -5.0  23.0  310  13  7   2.4   1.3
 11000  -4.3  24.3  275   9  4   2.0   1.1 |  -4.6  23.7  310  11  6   2.6   1.4
 10500  -4.0  24.8  260   7  4   2.2   1.2 |  -4.2  24.4  305   9  5   2.2   1.2
 10250  -3.9  25.0  255   7  4   1.9   1.0 |  -4.1  24.6  300   9  4   2.2   1.2
 10000  -3.7  25.3  245   7  3   3.1   1.7 |  -3.9  25.0  295   8  4   2.4   1.3
  9750  -3.4  25.9  235   6  3   4.1   2.3 |  -3.7  25.3  290   7  3   2.7   1.5
  9500  -3.1  26.4  230   6  3   3.5   1.9 |  -3.5  25.7  285   6  3   2.6   1.5
  9250  -2.8  27.0  225   6  3   3.8   2.1 |  -3.3  26.1  280   5  3   2.8   1.5
  9000  -2.6  27.3  215   6  3   3.2   1.8 |  -3.1  26.4  275   5  2   2.1   1.2
  8750  -2.4  27.7  215   6  3   1.3   0.7 |  -3.0  26.6  270   4  2   1.3   0.7
  8500  -2.3  27.9  220   5  3   0.4   0.2 |  -2.9  26.8  275   4  2   1.3   0.7
  8250  -2.3  27.9  225   5  3   0.7   0.4 |  -2.8  27.0  280   3  2   1.3   0.7
  8000  -2.3  27.9  230   4  2   0.1   0.0 |  -2.7  27.1  285   3  1   1.1   0.6
  7750  -2.3  27.9  245   3  1   0.6   0.3 |  -2.6  27.3  310   2  1   0.9   0.5
  7500  -2.2  28.0  270   2  1   1.0   0.5 |  -2.5  27.5  330   2  1   0.5   0.3
  7250  -2.1  28.2  305   2  1   2.0   1.1 |  -2.5  27.5  345   3  2   1.9   1.0
  7000  -1.9  28.6  335   2  1   4.0   2.2 |  -2.2  28.0  355   4  2   3.9   2.2
  6750  -1.6  29.1  350   3  2   4.1   2.3 |  -1.9  28.6  360   5  3   5.4   3.0
  6500  -1.3  29.7  355   3  2   4.1   2.3 |  -1.4  29.5  360   6  3   6.8   3.7
  6250  -0.9  30.4  360   4  2   4.5   2.5 |  -0.9  30.4  005   6  3   9.3   5.1
  6000  -0.6  30.9  005   3  2   4.6   2.5 |  -0.1  31.8  005   6  3  11.4   6.2
  5750  -0.3  31.5  010   3  2   5.0   2.7 |   0.7  33.3  005   6  3   9.6   5.3
  5500   0.1  32.2  360   3  1   4.6   2.5 |   1.5  34.7  360   6  3  11.4   6.3

           01/31/2015 at 1400 MST          |       01/31/2015 at 1700 MST
                                           |
K index... +18.7  LI... +3.5               | K index... +15.3  LI... +3.0
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 -58.6 -73.5  260  37 19   3.2   1.8 | -57.8 -72.0  260  39 20   3.3   1.8
 45000 -53.5 -64.3  260  49 25   2.0   1.1 | -52.9 -63.2  260  45 23   3.6   2.0
 40000 -53.1 -63.6  245  48 25   0.3   0.2 | -53.3 -63.9  255  44 22  -0.5  -0.3
 38000 -53.1 -63.6  240  49 25  -0.6  -0.3 | -53.4 -64.1  255  43 22   0.4   0.2
 36000 -53.4 -64.1  230  50 26  -0.6  -0.3 | -53.1 -63.6  260  41 21   0.4   0.2
 34000 -53.7 -64.7  225  53 27   3.3   1.8 | -52.9 -63.2  260  40 20   2.0   1.1
 32000 -49.3 -56.7  225  50 26   6.5   3.6 | -50.2 -58.4  260  33 17   4.6   2.5
 30000 -45.2 -49.4  230  47 24   8.8   4.8 | -47.4 -53.3  260  27 14   7.2   4.0
 29000 -42.6 -44.7  235  42 21   8.7   4.7 | -43.9 -47.0  270  27 14   9.4   5.2
 28000 -40.0 -40.0  245  37 19   8.7   4.7 | -41.1 -42.0  275  28 14   9.4   5.2
 27000 -37.4 -35.3  250  34 17   8.7   4.8 | -38.2 -36.8  280  29 15   9.4   5.2
 26000 -34.7 -30.5  255  31 16   9.3   5.1 | -35.5 -31.9  280  29 15   9.1   5.0
 25000 -31.9 -25.4  250  29 15   9.3   5.1 | -32.8 -27.0  280  29 15   9.1   5.0
 24000 -29.2 -20.6  250  27 14   9.5   5.2 | -30.1 -22.2  280  29 15   9.3   5.1
 23000 -26.8 -16.2  255  26 13   7.2   4.0 | -27.8 -18.0  290  29 15   6.8   3.7
 22000 -24.7 -12.5  255  25 13   7.2   4.0 | -25.7 -14.3  300  30 16   6.8   3.7
 21000 -22.6  -8.7  260  25 13   7.3   4.0 | -23.7 -10.7  315  33 17   6.8   3.7
 20000 -20.4  -4.7  265  24 12   7.3   4.0 | -21.7  -7.1  320  32 16   6.8   3.7
 19500 -19.3  -2.7  265  23 12   7.4   4.0 | -20.7  -5.3  320  31 16   6.8   3.7
 19000 -18.2  -0.8  270  23 12   7.4   4.0 | -19.6  -3.3  325  30 15   6.8   3.7
 18500 -17.1   1.2  270  22 11   7.5   4.1 | -18.6  -1.5  325  29 15   6.8   3.7
 18000 -16.1   3.0  275  22 11   6.0   3.3 | -17.7   0.1  325  28 15   6.1   3.4
 17500 -15.2   4.6  275  22 11   6.1   3.3 | -16.8   1.8  325  28 14   6.2   3.4
 17000 -14.3   6.3  280  22 11   5.8   3.2 | -15.9   3.4  330  27 14   6.2   3.4
 16500 -13.5   7.7  280  22 11   5.6   3.0 | -15.0   5.0  325  27 14   6.2   3.4
 16000 -12.7   9.1  285  21 11   5.6   3.1 | -14.1   6.6  325  27 14   6.2   3.4
 15500 -11.5  11.3  290  21 11   5.8   3.2 | -13.2   8.2  325  27 14   5.7   3.1
 15000 -10.6  12.9  290  21 11   5.8   3.2 | -12.0  10.4  320  27 14   5.9   3.2
 14500  -9.8  14.4  295  21 11   5.8   3.2 | -11.1  12.0  320  27 14   6.0   3.3
 14000  -8.9  16.0  300  21 11   5.8   3.2 | -10.3  13.5  320  27 14   6.0   3.3
 13500  -8.1  17.4  300  21 11   6.1   3.3 |  -9.4  15.1  320  26 13   6.1   3.3
 13000  -7.2  19.0  300  21 11   6.1   3.3 |  -8.6  16.5  320  25 13   6.1   3.4
 12500  -6.3  20.7  305  21 11   5.4   3.0 |  -7.7  18.1  320  24 12   5.7   3.1
 12000  -5.6  21.9  305  20 10   5.5   3.0 |  -6.9  19.6  320  23 12   5.7   3.2
 11500  -4.8  23.4  305  20 10   4.5   2.5 |  -6.1  21.0  325  22 11   5.3   2.9
 11000  -4.2  24.4  305  19 10   4.6   2.5 |  -5.3  22.5  325  21 11   5.4   3.0
 10500  -3.6  25.5  310  18  9   3.8   2.1 |  -4.6  23.7  330  20 10   3.9   2.1
 10250  -3.3  26.1  310  17  9   3.7   2.0 |  -4.3  24.3  330  20 10   3.5   1.9
 10000  -3.0  26.6  310  16  8   4.2   2.3 |  -4.1  24.6  335  19 10   5.6   3.1
  9750  -2.7  27.1  310  15  8   3.3   1.8 |  -3.6  25.5  335  19 10   5.8   3.2
  9500  -2.5  27.5  310  14  7   2.0   1.1 |  -3.3  26.1  340  18  9   3.7   2.0
  9250  -2.4  27.7  310  13  7   2.2   1.2 |  -3.0  26.6  340  18  9   4.3   2.4
  9000  -2.2  28.0  315  12  6   2.6   1.4 |  -2.7  27.1  340  17  9   3.9   2.2
  8750  -2.0  28.4  315  10  5   2.3   1.3 |  -2.4  27.7  345  16  8   3.7   2.0
  8500  -1.9  28.6  310   9  5   1.6   0.9 |  -2.1  28.2  345  15  8   3.8   2.1
  8250  -1.7  28.9  310   8  4   1.9   1.1 |  -1.8  28.8  345  14  7   3.6   2.0
  8000  -1.6  29.1  305   6  3   1.3   0.7 |  -1.6  29.1  350  14  7   4.3   2.4
  7750  -1.5  29.3  300   5  2   1.3   0.7 |  -1.2  29.8  350  12  6   4.3   2.4
  7500  -1.4  29.5  295   3  2   1.4   0.8 |  -0.9  30.4  350  11  6   3.7   2.1
  7250  -1.3  29.7  285   2  1   2.3   1.3 |  -0.7  30.7  350  10  5   3.7   2.0
  7000  -1.0  30.2  290   2  1   4.7   2.6 |  -0.4  31.3  345   8  4   3.3   1.8
  6750  -0.6  30.9  340   1  1   7.1   3.9 |  -0.2  31.6  335   6  3   2.6   1.4
  6500   0.0  32.0  360   2  1   8.0   4.4 |  -0.0  32.0  335   5  2   1.8   1.0
  6250   0.6  33.1  010   2  1   9.4   5.2 |   0.2  32.4  335   3  2   6.1   3.3
  6000   1.4  34.5  010   2  1  11.2   6.1 |   0.8  33.4  345   3  2   9.3   5.1
  5750   2.2  36.0  010   2  1  10.1   5.5 |   1.4  34.5  360   3  2   8.6   4.7
  5500   3.0  37.4  005   2  1  13.1   7.2 |   2.1  35.8  360   3  1  10.9   6.0
________________________________________________________________________________

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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