Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251241
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0641 MDT Monday, May 25, 2015

This forecast is for Monday, May 25, 2015:

If the trigger temperature of 55.6 F/13.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 798 ft/min (4.1 m/s)
   Maximum height of thermals.................. 14609 ft MSL (9324 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10497 ft MSL (5211 ft AGL)
Thermal soaring outlook for Tuesday 05/26...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 14888 ft MSL (9603 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 15380 ft MSL (10095 ft AGL)
Wave soaring outlook for Tuesday 05/26......... Poor

Remarks... None

Sunrise/Sunset.................... 05:37:24 / 20:15:14 MDT
Total possible sunshine........... 14 hr 37 min 50 sec (877 min 50 sec)
Altitude of sun at 12:56:31 MDT... 71.20 degrees

Upper air data from rawinsonde observation taken on 05/25/2015 at 0600 MDT

Freezing level.................. 9819 ft MSL (4534 ft AGL)
Convective condensation level... 11061 ft MSL (5776 ft AGL)
Lifted condensation level....... 12141 ft MSL (6855 ft AGL)
Lifted index.................... -2.7
K index......................... +22.4

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  -55.3 -67.5   225    2    1  -0.5  -0.3  107.5 225.5    51.7      M    M
 45000  -54.8 -66.6   170   15    8   2.2   1.2   82.4 180.3    40.0      M    M
 40000  -52.5 -62.5   215   17    9   0.2   0.1   63.1 145.5    30.1      M    M
 38000  -53.8 -64.8   235   17    9   6.1   3.4   52.4 126.3    23.7      M    M
 36000  -52.0 -61.6   275   12    6   5.5   3.0   46.4 115.5    20.2      M    M
 34000  -51.5 -60.7   265   16    8   3.1   1.7   38.8 101.9    15.4      M    M
 32000  -47.5 -53.5   275   18    9   5.7   3.2   36.2  97.2    13.9      M    M
 30000  -44.1 -47.4   265   22   11   7.4   4.0   32.0  89.5    11.1      M    M
 29000  -42.3 -44.1   265   18    9   5.0   2.7   30.3  86.5    10.0      M    M
 28000  -40.8 -41.4   265   14    7   4.9   2.7   28.4  83.1     8.6      M    M
 27000  -39.1 -38.4   270   10    5   8.6   4.7   26.9  80.5     7.6      M    M
 26000  -36.6 -33.9   275    6    3   8.3   4.6   26.4  79.5     7.2      M    M
 25000  -34.2 -29.6   295    9    5   7.6   4.1   25.7  78.3     6.8      M    M
 24000  -32.0 -25.6   315   12    6   8.2   4.5   24.9  76.9     6.2      M    M
 23000  -29.3 -20.7   285   13    7   9.0   4.9   24.6  76.3     6.0      M    M
 22000  -26.8 -16.2   265   12    6   8.1   4.5   24.1  75.5     5.7      M    M
 21000  -24.4 -11.9   270   14    7   8.2   4.5   23.5  74.3     5.2      M    M
 20000  -22.0  -7.6   270   16    8   8.0   4.4   23.0  73.4     4.8      M    M
 19500  -20.8  -5.4   270   16    8   7.7   4.2   22.6  72.8     4.5      M    M
 19000  -19.7  -3.5   275   17    9   7.7   4.2   22.3  72.2     4.2      M    M
 18500  -18.6  -1.5   265   19   10   7.6   4.2   22.0  71.5     3.9      M    M
 18000  -17.4   0.7   265   20   10   7.7   4.2   21.6  70.8     3.6      M    M
 17500  -16.5   2.3   265   18    9   7.1   3.9   21.0  69.8     3.1      M    M
 17000  -15.2   4.6   270   16    8   8.4   4.6   20.8  69.5     2.9      M    M
 16500  -13.9   7.0   270   14    7   7.4   4.0   20.6  69.1     2.8      M    M
 16000  -13.0   8.6   275   12    6   6.3   3.5   20.0  68.1     2.2      M    M
 15500  -11.6  11.1   285   13    7   7.0   3.8   19.1  66.5     1.4      M    M
 15000  -11.1  12.0   290   15    8   1.9   1.0   18.2  64.7     0.5      M    M
 14500  -10.3  13.5   290   17    8   7.0   3.8   17.5  63.4    -0.2    778  4.0
 14000   -9.3  15.3   295   18    9   6.6   3.6   17.0  62.5    -0.7    734  3.7
 13500   -8.2  17.2   295   16    8   8.7   4.8   16.6  61.8    -1.0    686  3.5
 13000   -6.9  19.6   295   14    7   8.8   4.8   16.4  61.5    -1.2    632  3.2
 12500   -5.6  21.9   295   12    6   8.9   4.9   16.2  61.2    -1.4    578  2.9
 12000   -4.4  24.1   295   10    5   6.9   3.8   16.0  60.8    -1.7    528  2.7
 11500   -3.4  25.9   295   10    5   7.1   3.9   15.5  59.9    -2.1    482  2.5
 11000   -2.4  27.7   290   11    5   7.1   3.9   15.1  59.1    -2.6    437  2.2
 10500   -1.4  29.5   290   11    6   7.1   3.9   14.6  58.4    -3.0    391  2.0
 10250   -0.8  30.6   290   11    6   7.0   3.8   14.5  58.0    -3.2    369  1.9
 10000   -0.3  31.5   290   11    6   7.4   4.1   14.3  57.7    -3.5    346  1.8
  9750    0.2  32.4   290   10    5   7.9   4.4   14.1  57.4    -3.6    321  1.6
  9500    0.8  33.4   290    8    4   7.8   4.3   14.0  57.1    -3.8    297  1.5
  9250    1.4  34.5   290    7    4   7.9   4.3   13.8  56.9    -4.0    273  1.4
  9000    1.9  35.4   290    6    3   7.9   4.3   13.7  56.6    -4.1    248  1.3
  8750    2.5  36.5   295    5    3   7.9   4.3   13.5  56.4    -4.3    224  1.1
  8500    3.1  37.6   305    5    2   7.9   4.3   13.4  56.1    -4.5    199  1.0
  8250    3.7  38.7   315    4    2   7.9   4.3   13.2  55.8    -4.6    175  0.9
  8000    4.2  39.6   325    4    2   7.9   4.3   13.1  55.6    -4.8    150  0.8
  7750    4.8  40.6   340    4    2   7.9   4.3   13.0  55.3    -5.0    126  0.6
  7500    5.4  41.7   355    5    2   8.0   4.4   12.8  55.1    -5.2    101  0.5
  7250    6.0  42.8   005    5    3   8.1   4.5   12.7  54.9    -5.3     76  0.4
  7000    6.6  43.9   015    6    3   8.1   4.5   12.6  54.6    -5.4     50  0.3
  6750    7.2  45.0   010    5    2   8.0   4.4   12.4  54.4    -5.6     24  0.1
  6500    7.8  46.0   005    3    2   8.4   4.6   12.3  54.2    -5.7      M    M
  6250    8.4  47.1   350    2    1   7.2   3.9   12.2  54.0    -5.8      M    M
  6000    8.8  47.8   300    1    1   6.0   3.3   11.9  53.5    -6.1      M    M
  5750    9.0  48.2   290    1    0  -3.5  -1.9   11.4  52.6    -6.7      M    M
  5500    7.8  46.0   000    0    0 -25.8 -14.2    9.6  49.3    -8.7      M    M

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

           05/25/2015 at 0900 MDT          |       05/25/2015 at 1200 MDT
                                           |
K index... +22.9  LI... +273.2             | K index... +18.1  LI... +273.1
CAPE... +4.8  CIN... -3.7                  | CAPE... +47.7  CIN... -39.8
                                           |
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 -54.8 -66.6  215   5  3   0.6   0.3 | -55.1 -67.2  215   7  3   1.1   0.6
 45000 -53.9 -65.0  225  11  6   0.3   0.2 | -53.5 -64.3  250  13  7   0.1   0.1
 40000 -53.6 -64.5  295  10  5   0.2   0.1 | -53.7 -64.7  285  12  6  -0.1  -0.1
 38000 -53.1 -63.6  300  12  6   1.5   0.8 | -53.7 -64.7  295  13  7   0.2   0.1
 36000 -52.2 -62.0  295  12  6   1.5   0.8 | -53.5 -64.3  305  15  7   0.2   0.1
 34000 -50.9 -59.6  295  12  6   3.8   2.1 | -52.6 -62.7  315  15  8   5.9   3.2
 32000 -48.6 -55.5  310  12  6   3.7   2.1 | -49.1 -56.4  360  15  8   5.9   3.2
 30000 -45.8 -50.4  315  13  7   8.1   4.5 | -45.1 -49.2  015  19 10   8.8   4.8
 29000 -43.4 -46.1  310  14  7   8.1   4.5 | -42.5 -44.5  005  17  9   8.9   4.9
 28000 -41.0 -41.8  305  16  8   8.1   4.5 | -39.8 -39.6  355  16  8   8.9   4.9
 27000 -38.5 -37.3  305  17  9   8.4   4.6 | -37.2 -35.0  340  16  8   8.5   4.7
 26000 -35.9 -32.6  305  17  9   8.8   4.8 | -34.7 -30.5  330  17  9   8.2   4.5
 25000 -33.3 -27.9  305  17  9   8.8   4.8 | -32.2 -26.0  320  19 10   8.2   4.5
 24000 -30.6 -23.1  310  17  9   8.8   4.8 | -29.8 -21.6  315  21 11   8.4   4.6
 23000 -28.1 -18.6  310  17  9   8.4   4.6 | -27.2 -17.0  310  21 11   8.7   4.8
 22000 -25.6 -14.1  315  17  9   8.4   4.6 | -24.5 -12.1  310  21 11   8.7   4.8
 21000 -23.1  -9.6  320  16  8   8.1   4.4 | -22.0  -7.6  305  20 10   8.1   4.4
 20000 -20.8  -5.4  325  16  8   7.8   4.3 | -19.6  -3.3  305  18  9   7.8   4.3
 19500 -19.7  -3.5  325  16  8   7.8   4.3 | -18.5  -1.3  300  17  9   7.8   4.3
 19000 -18.5  -1.3  325  15  8   7.8   4.3 | -17.3   0.9  300  16  8   7.8   4.3
 18500 -17.4   0.7  330  15  8   7.7   4.2 | -16.2   2.8  300  15  8   7.4   4.1
 18000 -16.3   2.7  330  14  7   7.4   4.0 | -14.6   5.7  295  15  8   6.9   3.8
 17500 -14.6   5.7  330  13  7   7.2   4.0 | -13.6   7.5  295  15  8   6.8   3.7
 17000 -13.6   7.5  330  13  7   6.9   3.8 | -12.6   9.3  295  16  8   6.8   3.7
 16500 -12.6   9.3  325  12  6   6.9   3.8 | -11.6  11.1  295  16  8   6.8   3.7
 16000 -11.6  11.1  325  11  6   6.6   3.6 | -10.6  12.9  295  16  8   7.1   3.9
 15500 -10.6  12.9  325  11  5   6.6   3.6 |  -9.6  14.7  295  17  9   7.1   3.9
 15000  -9.6  14.7  325  10  5   6.8   3.7 |  -8.5  16.7  295  17  9   7.3   4.0
 14500  -8.6  16.5  325  10  5   6.8   3.7 |  -7.4  18.7  290  16  8   7.3   4.0
 14000  -7.6  18.3  325   9  5   6.7   3.7 |  -6.4  20.5  290  16  8   7.3   4.0
 13500  -6.7  19.9  325   9  5   6.7   3.7 |  -5.3  22.5  290  15  8   7.2   4.0
 13000  -5.7  21.7  325   9  5   6.8   3.8 |  -4.2  24.4  290  15  8   7.1   3.9
 12500  -4.7  23.5  330  10  5   7.1   3.9 |  -3.2  26.2  295  14  7   6.9   3.8
 12000  -3.6  25.5  330  10  5   7.1   3.9 |  -2.2  28.0  295  14  7   7.0   3.9
 11500  -2.6  27.3  325  10  5   7.2   3.9 |  -1.2  29.8  300  13  7   7.2   3.9
 11000  -1.5  29.3  320  10  5   6.8   3.8 |  -0.1  31.8  300  13  6   7.0   3.8
 10500  -0.6  30.9  315  11  5   5.9   3.3 |   0.9  33.6  305  12  6   6.3   3.4
 10250  -0.1  31.8  315  11  6   7.8   4.3 |   1.3  34.3  310  11  6   8.2   4.5
 10000   0.5  32.9  310  12  6   9.4   5.2 |   2.0  35.6  315  11  6   8.0   4.4
  9750   1.2  34.2  315  12  6   8.4   4.6 |   2.5  36.5  320   9  5   5.9   3.3
  9500   1.8  35.2  315  13  7   8.4   4.6 |   2.9  37.2  330   8  4   6.5   3.6
  9250   2.4  36.3  315  14  7   8.3   4.5 |   3.3  37.9  340   7  4   6.4   3.5
  9000   3.0  37.4  315  14  7   7.8   4.3 |   3.8  38.8  350   6  3   8.2   4.5
  8750   3.6  38.5  315  15  8   7.9   4.3 |   4.5  40.1  355   6  3   9.5   5.2
  8500   4.2  39.6  320  15  8   8.0   4.4 |   5.1  41.2  360   5  3   9.1   5.0
  8250   4.8  40.6  320  16  8   8.1   4.5 |   5.8  42.4  005   5  2   9.8   5.4
  8000   5.4  41.7  320  16  8   7.9   4.3 |   6.5  43.7  010   5  2  10.4   5.7
  7750   5.9  42.6  320  16  8   6.6   3.6 |   7.3  45.1  010   4  2   9.6   5.2
  7500   6.4  43.5  320  15  8   5.9   3.2 |   8.0  46.4  010   4  2   8.8   4.8
  7250   6.8  44.2  325  15  8   6.6   3.6 |   8.7  47.7  010   4  2   9.8   5.4
  7000   7.3  45.1  320  13  7   7.3   4.0 |   9.4  48.9  015   4  2  10.7   5.9
  6750   7.8  46.0  320  11  6   6.5   3.6 |  10.2  50.4  015   4  2   9.9   5.4
  6500   8.2  46.8  315   9  4   7.1   3.9 |  10.9  51.6  015   4  2   9.9   5.4
  6250   8.8  47.8  315   7  3  10.1   5.5 |  11.7  53.1  015   4  2  10.9   6.0
  6000   9.6  49.3  310   6  3  11.5   6.3 |  12.6  54.7  015   4  2  11.8   6.5
  5750  10.4  50.7  310   5  3  10.1   5.5 |  13.4  56.1  015   4  2   9.7   5.3
  5500  11.2  52.2  305   4  2  12.8   7.0 |  14.2  57.6  015   4  2  14.3   7.8

           05/25/2015 at 1500 MDT          |       05/25/2015 at 1800 MDT
                                           |
K index... +22.1  LI... +272.3             | K index... +25.1  LI... +271.7
CAPE... +233.4  CIN... -10.9               | CAPE... +274.7  CIN... -2.6
                                           |
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 -55.9 -68.6  240  10  5   1.4   0.7 | -55.6 -68.1  255   9  5   1.0   0.5
 45000 -53.9 -65.0  260  14  7  -0.0  -0.0 | -54.3 -65.7  280  14  7  -1.0  -0.6
 40000 -54.4 -65.9  270  14  7  -0.3  -0.2 | -56.4 -69.5  260  18  9  -1.4  -0.8
 38000 -54.5 -66.1  285  14  7  -0.1  -0.1 | -56.2 -69.2  270  21 11   1.3   0.7
 36000 -54.6 -66.3  310  16  8  -0.1  -0.1 | -55.4 -67.7  280  26 13   1.3   0.7
 34000 -53.6 -64.5  320  17  9   7.6   4.2 | -53.4 -64.1  290  28 15   8.7   4.8
 32000 -49.1 -56.4  335  15  8   7.6   4.2 | -48.0 -54.4  295  22 11   8.9   4.9
 30000 -44.3 -47.7  345  14  7   9.2   5.0 | -42.7 -44.9  295  17  9   8.9   4.9
 29000 -41.5 -42.7  335  14  7   9.2   5.1 | -39.4 -38.9  295  15  8   8.9   4.9
 28000 -38.0 -36.4  320  15  8   9.3   5.1 | -36.7 -34.1  295  14  7   8.9   4.9
 27000 -35.3 -31.5  315  16  8   8.8   4.8 | -34.1 -29.4  295  13  7   8.5   4.7
 26000 -32.7 -26.9  310  17  9   8.9   4.9 | -31.5 -24.7  295  13  7   8.5   4.7
 25000 -30.0 -22.0  310  19 10   8.9   4.9 | -29.0 -20.2  295  14  7   8.5   4.7
 24000 -27.4 -17.3  305  20 10   8.3   4.5 | -26.5 -15.7  295  14  7   7.7   4.2
 23000 -25.0 -13.0  305  21 11   8.1   4.4 | -24.3 -11.7  300  15  8   7.6   4.2
 22000 -22.6  -8.7  305  21 11   8.1   4.4 | -22.0  -7.6  305  15  8   7.7   4.2
 21000 -20.3  -4.5  305  22 11   7.4   4.0 | -19.8  -3.6  310  16  8   7.2   4.0
 20000 -18.1  -0.6  300  22 11   7.4   4.1 | -17.6   0.3  310  18  9   7.3   4.0
 19500 -17.0   1.4  300  22 11   7.4   4.1 | -16.6   2.1  310  18 10   7.3   4.0
 19000 -15.9   3.4  300  22 11   7.4   4.1 | -15.5   4.1  305  19 10   7.3   4.0
 18500 -14.8   5.4  300  22 11   6.9   3.8 | -14.4   6.1  305  20 10   7.1   3.9
 18000 -13.8   7.2  295  23 12   6.8   3.7 | -13.4   7.9  300  21 11   7.1   3.9
 17500 -12.8   9.0  295  24 12   6.7   3.7 | -12.3   9.9  300  21 11   7.2   4.0
 17000 -11.8  10.8  295  24 12   6.6   3.6 | -11.2  11.8  295  22 11   7.6   4.2
 16500 -10.9  12.4  295  24 13   6.6   3.6 | -10.1  13.8  295  22 12   7.7   4.2
 16000  -9.9  14.2  290  25 13   7.2   4.0 |  -9.0  15.8  290  23 12   7.2   3.9
 15500  -8.8  16.2  290  25 13   7.3   4.0 |  -8.0  17.6  290  22 12   7.2   3.9
 15000  -7.2  19.0  290  25 13   8.4   4.6 |  -6.5  20.3  290  21 11   7.0   3.8
 14500  -6.0  21.2  285  24 12   8.4   4.6 |  -5.4  22.3  290  20 10   7.0   3.8
 14000  -4.8  23.4  285  23 12   7.6   4.2 |  -4.4  24.1  285  18  9   6.8   3.7
 13500  -3.8  25.2  280  21 11   7.6   4.2 |  -3.4  25.9  280  16  8   6.8   3.7
 13000  -2.7  27.1  280  18  9   6.6   3.6 |  -2.5  27.5  270  14  7   6.8   3.7
 12500  -1.8  28.8  275  15  8   6.2   3.4 |  -1.5  29.3  260  14  7   6.8   3.7
 12000  -1.0  30.2  275  12  6   5.5   3.0 |  -0.5  31.1  245  13  7   5.8   3.2
 11500  -0.3  31.5  275   7  3   5.0   2.7 |   0.2  32.4  240  11  6   5.3   2.9
 11000   0.4  32.7  280   2  1   5.4   3.0 |   0.9  33.6  230   9  5   5.1   2.8
 10500   1.3  34.3  045   2  1   5.1   2.8 |   1.6  34.9  230   4  2   4.2   2.3
 10250   1.7  35.1  060   3  2   9.0   5.0 |   2.0  35.6  225   2  1   8.7   4.8
 10000   2.5  36.5  060   4  2  11.5   6.3 |   2.8  37.0  090   1  0  11.5   6.3
  9750   3.2  37.8  060   4  2   9.5   5.2 |   3.5  38.3  075   2  1   9.0   4.9
  9500   4.0  39.2  055   4  2  10.0   5.5 |   4.2  39.6  070   3  1   9.8   5.4
  9250   4.7  40.5  055   4  2   9.8   5.4 |   4.9  40.8  065   4  2   9.2   5.0
  9000   5.4  41.7  055   4  2   9.8   5.4 |   5.5  41.9  065   4  2   9.5   5.2
  8750   6.1  43.0  055   4  2   9.9   5.4 |   6.3  43.3  065   5  2  10.1   5.5
  8500   6.9  44.4  050   4  2   9.7   5.3 |   7.0  44.6  065   5  2   9.7   5.3
  8250   7.6  45.7  050   5  2  10.4   5.7 |   7.7  45.9  060   5  2  10.6   5.8
  8000   8.4  47.1  050   5  2  10.7   5.9 |   8.6  47.5  060   5  3  10.8   5.9
  7750   9.2  48.6  050   5  2   9.7   5.3 |   9.3  48.7  060   5  3   9.5   5.2
  7500   9.9  49.8  050   5  2   9.1   5.0 |  10.0  50.0  060   5  3   9.0   4.9
  7250  10.6  51.1  050   5  3  10.2   5.6 |  10.7  51.3  060   6  3  10.1   5.5
  7000  11.4  52.5  045   5  3  11.0   6.1 |  11.5  52.7  060   6  3  10.8   6.0
  6750  12.1  53.8  045   5  3   9.4   5.2 |  12.2  54.0  055   6  3   9.3   5.1
  6500  12.8  55.0  045   5  3   9.3   5.1 |  12.9  55.2  055   6  3   9.1   5.0
  6250  13.6  56.5  045   5  3  10.9   6.0 |  13.7  56.7  055   6  3  10.5   5.8
  6000  14.4  57.9  045   5  3  12.1   6.6 |  14.5  58.1  055   6  3  11.0   6.0
  5750  15.3  59.5  040   5  3   9.6   5.2 |  15.3  59.5  055   6  3   9.9   5.4
  5500  16.0  60.8  040   5  3  13.8   7.6 |  16.0  60.8  050   6  3  12.0   6.6
________________________________________________________________________________

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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