Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 221323
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0723 MDT Friday, May 22, 2015

This forecast is for Friday, May 22, 2015:

If the trigger temperature of 57.5 F/14.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 158 ft/min (0.8 m/s)
   Maximum height of thermals.................. 12592 ft MSL (7307 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1115 MDT
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................. 9961 ft MSL (4676 ft AGL)
Thermal soaring outlook for Saturday 05/23..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15880 ft MSL (10595 ft AGL)
Wave soaring outlook for Saturday 05/23........ Poor

Remarks... Extremely moist airmass will remain in place as an upper disturbance
           tracks northward over eastern colorado today.

Sunrise/Sunset.................... 05:39:26 / 20:12:40 MDT
Total possible sunshine........... 14 hr 33 min 14 sec (873 min 14 sec)
Altitude of sun at 12:56:15 MDT... 70.65 degrees

Upper air data from rawinsonde observation taken on 05/22/2015 at 0600 MDT

Freezing level.................. 10436 ft MSL (5151 ft AGL)
Convective condensation level... 10165 ft MSL (4880 ft AGL)
Lifted condensation level....... 11436 ft MSL (6150 ft AGL)
Lifted index.................... +0.2
K index......................... +24.5

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  -59.7 -75.5   215   39   20  -3.9  -2.1   98.6 209.5    46.1      M    M
 45000  -56.7 -70.1   235   21   11   8.0   4.4   78.9 174.1    37.3      M    M
 40000  -57.0 -70.6   225   35   18 -16.6  -9.1   55.5 131.8    24.4      M    M
 38000  -60.5 -76.9   200   31   16  -3.7  -2.0   41.5 106.7    15.7      M    M
 36000  -57.7 -71.9   165   36   18   8.9   4.9   37.0  98.5    13.0      M    M
 34000  -52.3 -62.1   170   37   19   8.9   4.9   36.4  97.5    12.9      M    M
 32000  -46.3 -51.3   160   30   15   8.9   4.9   35.4  95.7    12.5      M    M
 30000  -40.9 -41.6   160   23   12   9.0   4.9   34.9  94.8    12.5      M    M
 29000  -38.2 -36.8   170   18    9   9.0   4.9   34.5  94.2    12.3      M    M
 28000  -35.6 -32.1   185   14    7   8.6   4.7   34.2  93.5    12.2      M    M
 27000  -33.1 -27.6   205   12    6   8.6   4.7   33.8  92.8    12.0      M    M
 26000  -30.5 -22.9   185   12    6   8.6   4.7   33.3  91.9    11.8      M    M
 25000  -27.9 -18.2   170   13    7   8.6   4.7   32.9  91.2    11.5      M    M
 24000  -25.7 -14.3   145   13    7   7.3   4.0   32.1  89.7    11.0      M    M
 23000  -23.5 -10.3   110   12    6   7.4   4.0   31.2  88.2    10.4      M    M
 22000  -21.3  -6.3   110    6    3   7.4   4.0   30.3  86.6     9.8      M    M
 21000  -19.1  -2.4   325    1    0   7.4   4.1   29.5  85.2     9.2      M    M
 20000  -17.0   1.4   230    4    2   7.5   4.1   28.7  83.6     8.5      M    M
 19500  -15.9   3.4   220    3    2   6.3   3.4   28.2  82.7     8.1      M    M
 19000  -15.0   5.0   200    2    1   6.0   3.3   27.5  81.5     7.6      M    M
 18500  -14.2   6.4   175    2    1   5.9   3.2   26.9  80.4     7.0      M    M
 18000  -13.3   8.1   170    5    2   5.8   3.2   26.2  79.2     6.5      M    M
 17500  -12.5   9.5   170    7    4   5.8   3.2   25.6  78.0     5.9      M    M
 17000  -11.6  11.1   170    9    5   5.9   3.2   25.0  76.9     5.4      M    M
 16500  -10.7  12.7   160   12    6   5.9   3.2   24.3  75.8     4.8      M    M
 16000   -9.5  14.9   145   16    8   5.9   3.2   23.4  74.0     4.0      M    M
 15500   -8.6  16.5   145   15    8   5.9   3.2   22.7  72.8     3.4      M    M
 15000   -7.8  18.0   150   14    7   5.9   3.2   22.0  71.7     2.8      M    M
 14500   -6.9  19.6   150   14    7   5.9   3.2   21.4  70.5     2.2      M    M
 14000   -6.0  21.2   150   13    7   5.9   3.2   20.8  69.5     1.7      M    M
 13500   -5.2  22.6   140   12    6   5.9   3.3   20.2  68.3     1.0      M    M
 13000   -4.3  24.3   135   12    6   5.9   3.3   19.5  67.2     0.4      M    M
 12500   -3.5  25.7   140   13    6   5.9   3.3   18.9  66.0    -0.2    544  2.8
 12000   -2.6  27.3   145   13    7   6.0   3.3   18.3  64.9    -0.8    504  2.6
 11500   -1.8  28.8   155   13    7   6.0   3.3   17.6  63.7    -1.5    464  2.4
 11000   -0.9  30.4   160   13    7   6.1   3.3   17.0  62.6    -2.1    423  2.1
 10500   -0.1  31.8   165   10    5   7.2   3.9   16.3  61.4    -2.8    383  1.9
 10250    0.6  33.1   170    8    4   8.7   4.8   16.2  61.2    -2.9    357  1.8
 10000    1.2  34.2   175    6    3   8.6   4.7   16.1  61.0    -3.0    330  1.7
  9750    1.8  35.2   175    5    2   6.5   3.5   16.0  60.8    -3.1    305  1.5
  9500    2.1  35.8   175    3    2   3.0   1.6   15.6  60.0    -3.6    288  1.5
  9250    2.3  36.1   175    2    1   2.3   1.2   15.0  59.0    -4.1    276  1.4
  9000    2.4  36.3   000    0    0   2.6   1.4   14.4  58.0    -4.7    263  1.3
  8750    2.6  36.7   175    1    1   2.0   1.1   13.9  57.0    -5.3    251  1.3
  8500    2.8  37.0   175    3    1   4.0   2.2   13.3  56.0    -5.8    238  1.2
  8250    3.2  37.8   175    4    2   6.2   3.4   13.0  55.4    -6.2    219  1.1
  8000    3.6  38.5   175    5    3   5.9   3.2   12.7  54.9    -6.5    198  1.0
  7750    4.1  39.4   170    8    4   6.0   3.3   12.4  54.3    -6.8    178  0.9
  7500    4.5  40.1   170   11    6   5.9   3.3   12.1  53.8    -7.1    157  0.8
  7250    4.9  40.8   170   14    7   6.0   3.3   11.8  53.3    -7.4    137  0.7
  7000    5.4  41.7   170   17    9   6.0   3.3   11.6  52.8    -7.7    117  0.6
  6750    5.8  42.4   170   15    8   6.0   3.3   11.3  52.3    -8.0     96  0.5
  6500    6.2  43.2   165   12    6   5.9   3.3   11.0  51.7    -8.4     76  0.4
  6250    6.7  44.1   165   10    5   6.0   3.3   10.7  51.2    -8.7     55  0.3
  6000    7.1  44.8   160    7    4   5.7   3.2   10.4  50.7    -9.0     35  0.2
  5750    7.5  45.5   145    6    3   6.8   3.7   10.1  50.2    -9.3     14  0.1
  5500    8.1  46.6   120    5    2   9.4   5.1   10.0  50.0    -9.5      M    M

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

           05/22/2015 at 0900 MDT          |       05/22/2015 at 1200 MDT
                                           |
K index... +23.1  LI... +275.8             | K index... +23.3  LI... +273.7
CAPE... 0.0  CIN... -0.2                   | 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 -56.7 -70.1  255  32 16   0.6   0.3 | -56.9 -70.4  255  37 19   0.6   0.3
 45000 -55.8 -68.4  245  37 19  -0.0  -0.0 | -55.9 -68.6  245  43 22   1.0   0.6
 40000 -55.9 -68.6  240  41 21  -0.0  -0.0 | -54.4 -65.9  245  52 27   1.0   0.6
 38000 -55.4 -67.7  225  33 17   1.3   0.7 | -53.6 -64.5  240  45 23   1.6   0.9
 36000 -54.7 -66.5  190  27 14   1.3   0.7 | -52.6 -62.7  235  34 18   1.6   0.9
 34000 -52.5 -62.5  160  29 15   9.3   5.1 | -50.8 -59.4  220  25 13   7.0   3.9
 32000 -46.8 -52.2  165  24 12   9.5   5.2 | -46.4 -51.5  190  21 11   7.2   4.0
 30000 -41.2 -42.2  165  20 10   9.3   5.1 | -41.2 -42.2  170  20 10   8.9   4.9
 29000 -37.8 -36.0  170  19 10   9.3   5.1 | -38.5 -37.3  170  18  9   8.9   4.9
 28000 -35.0 -31.0  175  19 10   9.3   5.1 | -35.9 -32.6  175  16  8   8.9   4.9
 27000 -32.4 -26.3  175  18  9   7.7   4.2 | -33.3 -27.9  185  14  7   7.1   3.9
 26000 -30.0 -22.0  175  15  8   7.9   4.3 | -31.2 -24.2  195  15  8   7.3   4.0
 25000 -27.7 -17.9  180  13  7   7.9   4.3 | -29.0 -20.2  205  17  9   7.3   4.0
 24000 -25.4 -13.7  180  11  6   7.4   4.0 | -26.8 -16.2  215  18  9   7.5   4.1
 23000 -23.3  -9.9  180   8  4   7.2   3.9 | -24.6 -12.3  220  20 11   7.6   4.2
 22000 -21.2  -6.2  180   6  3   7.2   3.9 | -22.3  -8.1  225  23 12   7.7   4.2
 21000 -19.1  -2.4  185   3  2   6.6   3.6 | -20.1  -4.2  225  25 13   6.4   3.5
 20000 -17.1   1.2  250   2  1   6.7   3.7 | -18.3  -0.9  225  24 12   6.4   3.5
 19500 -16.1   3.0  280   2  1   6.7   3.7 | -17.3   0.9  225  24 12   6.4   3.5
 19000 -15.2   4.6  300   3  2   6.7   3.7 | -16.4   2.5  225  24 12   6.4   3.5
 18500 -14.2   6.4  305   5  2   6.4   3.5 | -15.5   4.1  225  23 12   6.7   3.7
 18000 -13.3   8.1  305   6  3   6.3   3.5 | -14.5   5.9  230  20 10   6.9   3.8
 17500 -12.4   9.7  305   7  4   6.3   3.5 | -13.5   7.7  230  18  9   6.9   3.8
 17000 -11.4  11.5  300   9  4   6.3   3.4 | -12.5   9.5  235  16  8   6.9   3.8
 16500 -10.5  13.1  300  10  5   6.4   3.5 | -11.4  11.5  245  16  8   6.9   3.8
 16000  -9.7  14.5  300  12  6   5.2   2.9 | -10.4  13.3  250  16  8   6.8   3.7
 15500  -9.0  15.8  300  15  8   5.0   2.7 |  -8.9  16.0  245  18  9   6.7   3.7
 15000  -7.9  17.8  300  20 10   5.0   2.7 |  -7.9  17.8  245  20 10   7.5   4.1
 14500  -7.2  19.0  300  23 12   5.0   2.7 |  -6.8  19.8  245  22 11   7.5   4.1
 14000  -6.4  20.5  300  26 14   5.2   2.9 |  -5.8  21.6  245  23 12   6.9   3.8
 13500  -5.6  21.9  295  30 15   5.3   2.9 |  -4.8  23.4  255  24 12   6.8   3.7
 13000  -4.8  23.4  295  33 17   6.0   3.3 |  -3.8  25.2  260  26 13   6.6   3.6
 12500  -3.9  25.0  290  34 17   6.4   3.5 |  -2.8  27.0  270  29 15   6.5   3.6
 12000  -2.9  26.8  290  34 18   6.8   3.7 |  -1.9  28.6  275  32 16   6.3   3.5
 11500  -1.9  28.6  290  32 16   7.0   3.9 |  -1.0  30.2  280  32 16   6.2   3.4
 11000  -0.9  30.4  290  29 15   5.8   3.2 |  -0.1  31.8  280  32 16   5.5   3.0
 10500  -0.2  31.6  295  26 13   4.5   2.5 |   0.6  33.1  280  30 15   4.2   2.3
 10250   0.1  32.2  295  24 12   6.2   3.4 |   1.0  33.8  280  28 15   8.3   4.5
 10000   0.6  33.1  295  21 11   5.6   3.1 |   1.7  35.1  280  26 13   8.7   4.8
  9750   0.9  33.6  300  20 10   3.5   1.9 |   2.2  36.0  280  24 12   4.8   2.6
  9500   1.1  34.0  300  18  9   4.0   2.2 |   2.6  36.7  285  22 11   6.1   3.4
  9250   1.4  34.5  300  17  9   4.0   2.2 |   3.0  37.4  285  20 10   4.7   2.6
  9000   1.7  35.1  305  15  8   4.1   2.2 |   3.2  37.8  285  17  9   2.2   1.2
  8750   2.0  35.6  305  14  7   3.7   2.0 |   3.3  37.9  290  15  7   1.7   0.9
  8500   2.2  36.0  305  12  6   3.6   2.0 |   3.4  38.1  290  12  6   1.9   1.0
  8250   2.5  36.5  310  11  5   3.7   2.0 |   3.5  38.3  295   9  5   2.9   1.6
  8000   2.8  37.0  300   8  4   3.9   2.2 |   3.8  38.8  300   6  3   5.2   2.8
  7750   3.1  37.6  285   6  3   4.6   2.5 |   4.2  39.6  320   3  1   6.9   3.8
  7500   3.4  38.1  265   5  3   5.0   2.7 |   4.7  40.5  030   1  1   7.7   4.2
  7250   3.8  38.8  235   5  2   5.4   2.9 |   5.3  41.5  075   3  1   9.1   5.0
  7000   4.2  39.6  200   5  2   6.2   3.4 |   6.0  42.8  080   3  2  10.5   5.8
  6750   4.6  40.3  170   6  3   4.2   2.3 |   6.8  44.2  085   4  2   9.3   5.1
  6500   4.9  40.8  150   8  4   5.6   3.1 |   7.5  45.5  085   4  2   9.8   5.4
  6250   5.5  41.9  140   8  4   9.8   5.4 |   8.3  46.9  080   4  2  11.5   6.3
  6000   6.2  43.2  130   7  4   9.8   5.4 |   9.1  48.4  080   4  2  11.3   6.2
  5750   6.9  44.4  120   7  4  10.7   5.9 |  10.0  50.0  080   4  2  11.9   6.6
  5500   7.8  46.0  115   7  3  15.4   8.4 |  11.1  52.0  080   4  2  19.4  10.6

           05/22/2015 at 1500 MDT          |       05/22/2015 at 1800 MDT
                                           |
K index... +23.8  LI... +271.2             | K index... +26.7  LI... +270.5
CAPE... +233.8  CIN... M                   | CAPE... +411.0  CIN... -7.8
                                           |
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 -57.1 -70.8  245  34 17   0.5   0.3 | -57.8 -72.0  240  35 18   0.2   0.1
 45000 -56.2 -69.2  245  54 28   0.8   0.5 | -57.3 -71.1  240  57 29   1.1   0.6
 40000 -54.9 -66.8  245  66 34   0.9   0.5 | -55.7 -68.3  245  71 37   1.1   0.6
 38000 -53.3 -63.9  245  70 36   3.5   1.9 | -53.6 -64.5  245  77 40   4.6   2.5
 36000 -51.2 -60.2  250  73 38   3.5   1.9 | -50.8 -59.4  250  84 43   4.6   2.5
 34000 -48.6 -55.5  255  71 37   6.5   3.6 | -47.8 -54.0  250  88 45   6.2   3.4
 32000 -44.6 -48.3  250  56 29   6.6   3.6 | -43.6 -46.5  250  85 44   6.2   3.4
 30000 -40.1 -40.2  245  40 21   6.9   3.8 | -39.6 -39.3  250  75 39   7.2   3.9
 29000 -38.0 -36.4  245  35 18   6.9   3.8 | -37.5 -35.5  250  64 33   7.2   3.9
 28000 -36.0 -32.8  240  29 15   6.9   3.8 | -35.4 -31.7  250  53 27   7.2   4.0
 27000 -33.9 -29.0  235  25 13   7.5   4.1 | -33.2 -27.8  250  43 22   7.4   4.1
 26000 -31.6 -24.9  235  25 13   7.5   4.1 | -31.0 -23.8  245  39 20   7.4   4.1
 25000 -29.4 -20.9  235  25 13   7.5   4.1 | -28.8 -19.8  240  34 18   7.4   4.1
 24000 -27.2 -17.0  235  25 13   7.4   4.1 | -26.6 -15.9  235  31 16   7.4   4.1
 23000 -25.0 -13.0  240  27 14   7.4   4.1 | -24.4 -11.9  240  33 17   7.5   4.1
 22000 -22.8  -9.0  245  30 15   7.5   4.1 | -22.2  -8.0  240  35 18   7.5   4.1
 21000 -20.6  -5.1  245  32 16   7.0   3.9 | -20.0  -4.0  240  36 19   7.1   3.9
 20000 -18.5  -1.3  250  33 17   7.1   3.9 | -17.9  -0.2  240  36 18   7.1   3.9
 19500 -17.5   0.5  250  34 18   7.1   3.9 | -16.8   1.8  245  35 18   7.1   3.9
 19000 -16.4   2.5  250  35 18   7.1   3.9 | -15.8   3.6  245  35 18   7.1   3.9
 18500 -15.4   4.3  250  36 18   7.1   3.9 | -14.7   5.5  245  34 18   7.2   4.0
 18000 -14.3   6.3  245  35 18   7.2   3.9 | -13.6   7.5  240  33 17   7.2   4.0
 17500 -13.3   8.1  245  35 18   7.2   3.9 | -12.6   9.3  240  32 17   7.2   4.0
 17000 -12.2  10.0  245  34 18   7.3   4.0 | -11.5  11.3  240  32 16   7.2   4.0
 16500 -11.1  12.0  245  34 17   7.3   4.0 |  -9.9  14.2  235  31 16   7.4   4.0
 16000  -9.5  14.9  240  33 17   7.5   4.1 |  -8.8  16.2  235  30 16   7.6   4.2
 15500  -8.4  16.9  240  33 17   7.5   4.1 |  -7.7  18.1  230  29 15   7.7   4.2
 15000  -7.3  18.9  235  33 17   7.7   4.2 |  -6.6  20.1  225  28 15   7.2   4.0
 14500  -6.2  20.8  235  32 16   7.8   4.3 |  -5.6  21.9  220  27 14   7.4   4.0
 14000  -5.1  22.8  235  30 16   6.9   3.8 |  -4.6  23.7  215  25 13   6.6   3.6
 13500  -4.1  24.6  230  29 15   6.9   3.8 |  -3.6  25.5  210  24 12   6.6   3.6
 13000  -3.1  26.4  225  27 14   6.2   3.4 |  -2.7  27.1  200  23 12   6.4   3.5
 12500  -2.3  27.9  220  25 13   6.0   3.3 |  -1.8  28.8  190  23 12   6.3   3.5
 12000  -1.5  29.3  210  23 12   5.4   3.0 |  -0.9  30.4  180  22 11   7.5   4.1
 11500  -0.8  30.6  200  21 11   5.1   2.8 |   0.3  32.5  180  20 11   8.1   4.5
 11000  -0.0  32.0  190  20 10   5.0   2.8 |   1.4  34.5  170  19 10   6.8   3.7
 10500   0.7  33.3  180  18  9   4.5   2.5 |   2.3  36.1  165  17  9   5.4   2.9
 10250   1.0  33.8  180  16  8   7.2   4.0 |   2.7  36.9  160  16  8   8.6   4.7
 10000   1.6  34.9  170  14  7   8.3   4.6 |   3.4  38.1  155  15  8   9.8   5.4
  9750   2.1  35.8  165  12  6   6.5   3.6 |   4.0  39.2  150  14  7   7.3   4.0
  9500   2.6  36.7  160  10  5   7.0   3.8 |   4.6  40.3  140  13  7   8.2   4.5
  9250   3.1  37.6  145   9  4   7.0   3.8 |   5.1  41.2  135  12  6   7.1   3.9
  9000   3.6  38.5  135   8  4   8.8   4.8 |   5.6  42.1  130  12  6   7.1   3.9
  8750   4.3  39.7  130   7  4  10.1   5.5 |   6.2  43.2  120  11  6   8.1   4.4
  8500   5.0  41.0  120   7  4   9.8   5.4 |   6.8  44.2  110  11  5   7.6   4.2
  8250   5.7  42.3  115   7  4  10.0   5.5 |   7.3  45.1  100  11  5   8.6   4.7
  8000   6.5  43.7  110   7  4   9.9   5.5 |   8.0  46.4  090  10  5   8.9   4.9
  7750   7.2  45.0  110   7  4   9.7   5.3 |   8.6  47.5  080  10  5   7.5   4.1
  7500   7.9  46.2  105   7  3   9.6   5.2 |   9.1  48.4  075  11  5   6.9   3.8
  7250   8.7  47.7  105   7  3  10.5   5.8 |   9.6  49.3  065  11  6   8.2   4.5
  7000   9.5  49.1  105   6  3  11.3   6.2 |  10.3  50.5  060  11  6   9.2   5.1
  6750  10.3  50.5  100   6  3   9.7   5.3 |  10.9  51.6  055  11  6   8.7   4.7
  6500  11.0  51.8  100   6  3   9.8   5.4 |  11.6  52.9  050  11  6   9.2   5.0
  6250  11.8  53.2  095   6  3  11.3   6.2 |  12.3  54.1  045  11  6  10.2   5.6
  6000  12.6  54.7  095   6  3  11.4   6.2 |  13.0  55.4  045  11  6  10.6   5.8
  5750  13.4  56.1  095   6  3  10.9   6.0 |  13.8  56.8  040  11  6   9.9   5.4
  5500  14.4  57.9  090   6  3  16.4   9.0 |  14.5  58.1  040  10  5  10.0   5.5
________________________________________________________________________________

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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