Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241255
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0555 MST Tuesday, February 24, 2015

This forecast is for Tuesday, February 24, 2015:

If the trigger temperature of 41.0 F/5.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 279 ft/min (1.4 m/s)
   Maximum height of thermals.................. 9289 ft MSL (4004 ft AGL)

Forecast maximum temperature................... 41.0 F/5.5 C
Time of trigger temperature.................... 1400 MST
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................. 5968 ft MSL (683 ft AGL)
Thermal soaring outlook for Wednesday 02/25.... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 12168 ft MSL (6883 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 12659 ft MSL (7374 ft AGL)
Wave soaring outlook for Wednesday 02/25....... Fair

Remarks...

Sunrise/Sunset.................... 06:39:58 / 17:44:37 MST
Total possible sunshine........... 11 hr 4 min 38 sec (664 min 38 sec)
Altitude of sun at 12:12:34 MST... 40.89 degrees

Upper air data from rawinsonde observation taken on 02/24/2015 at 0500 MST

Freezing level.................. 5979 ft MSL (694 ft AGL)
Additional freezing level....... 6468 ft MSL (1183 ft AGL)
Convective condensation level... 23600 ft MSL (18315 ft AGL)
Lifted condensation level....... 16110 ft MSL (10825 ft AGL)
Lifted index.................... +15.7
K index......................... -25.4

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  -57.2 -71.0   290   40   21  -5.0  -2.7  106.1 223.0    57.6      M    M
 45000  -56.4 -69.5   295   31   16  -1.3  -0.7   82.6 180.6    47.3      M    M
 40000  -56.1 -69.0   265   27   14   3.2   1.8   58.8 137.9    35.2      M    M
 38000  -56.6 -69.9   345    4    2  -7.4  -4.0   49.2 120.6    29.7      M    M
 36000  -57.9 -72.2   075   15    8   9.9   5.4   38.7 101.6    23.2      M    M
 34000  -53.4 -64.1   085   25   13  -2.2  -1.2   36.9  98.3    22.6      M    M
 32000  -50.0 -58.0   070   36   18   6.8   3.7   33.4  92.1    20.7      M    M
 30000  -45.3 -49.5   075   31   16   8.5   4.6   31.9  89.4    20.1      M    M
 29000  -42.2 -44.0   075   29   15   7.4   4.1   31.1  87.9    19.8      M    M
 28000  -40.0 -40.0   070   28   14   7.4   4.1   30.1  86.1    19.3      M    M
 27000  -37.8 -36.0   065   27   14   7.4   4.1   29.2  84.5    18.8      M    M
 26000  -35.7 -32.3   060   26   13   6.9   3.8   28.2  82.7    18.3      M    M
 25000  -33.6 -28.5   055   25   13   7.0   3.8   27.2  80.9    17.7      M    M
 24000  -31.4 -24.5   055   23   12   8.8   4.8   26.3  79.4    17.2      M    M
 23000  -28.8 -19.8   055   22   11   8.6   4.7   25.9  78.6    17.0      M    M
 22000  -26.3 -15.3   055   20   10   6.2   3.4   25.4  77.8    16.9      M    M
 21000  -24.9 -12.8   050   19   10   4.1   2.3   23.5  74.3    15.5      M    M
 20000  -22.6  -8.7   050   17    9   9.3   5.1   22.8  73.1    15.0      M    M
 19500  -21.2  -6.2   050   16    8   9.6   5.3   22.7  72.9    15.0      M    M
 19000  -20.0  -4.0   050   15    8   5.8   3.2   22.4  72.4    14.9      M    M
 18500  -19.2  -2.6   050   14    7   5.4   3.0   21.7  71.0    14.3      M    M
 18000  -18.5  -1.3   050   14    7   5.4   2.9   20.9  69.6    13.6      M    M
 17500  -17.5   0.5   045   14    7   7.2   3.9   20.3  68.6    13.2      M    M
 17000  -16.6   2.1   040   13    7   4.0   2.2   19.7  67.5    12.8      M    M
 16500  -15.6   3.9   035   13    7   9.9   5.4   19.2  66.5    12.4      M    M
 16000  -14.2   6.4   025   13    7   9.2   5.0   19.1  66.4    12.4      M    M
 15500  -12.9   8.8   020   12    6   8.5   4.6   18.9  65.9    12.3      M    M
 15000  -12.1  10.2   015   12    6   2.0   1.1   18.1  64.6    11.7      M    M
 14500  -11.4  11.5   360   11    6   3.2   1.8   16.4  61.6    10.3      M    M
 14000  -10.9  12.4   355   11    6   3.2   1.8   15.4  59.6     9.4      M    M
 13500  -10.4  13.3   005   11    6   5.8   3.2   14.3  57.8     8.5      M    M
 13000   -9.3  15.3   005   11    6   7.3   4.0   14.0  57.1     8.2      M    M
 12500   -8.4  16.9   355   14    7   0.7   0.4   13.4  56.1     7.7      M    M
 12000   -8.8  16.2   345   16    8  -0.0  -0.0   11.3  52.3     5.8      M    M
 11500   -8.2  17.2   345   17    9   5.0   2.7   10.3  50.6     5.0      M    M
 11000   -7.5  18.5   345   17    9   5.0   2.7    9.6  49.2     4.3      M    M
 10500   -6.8  19.8   345   18    9   4.7   2.6    8.8  47.9     3.6      M    M
 10250   -6.6  20.1   345   18    9   0.1   0.1    8.3  47.0     3.1      M    M
 10000   -6.9  19.6   340   20   11  -7.0  -3.8    7.3  45.1     2.1      M    M
  9750   -7.3  18.9   345   17    9  -2.0  -1.1    6.0  42.8     0.9      M    M
  9500   -7.1  19.2   355   15    8   4.2   2.3    5.5  41.8     0.4      M    M
  9250   -6.9  19.6   005   12    6   1.7   0.9    4.9  40.8    -0.2    275  1.4
  9000   -6.7  19.9   020   11    6   6.0   3.3    4.4  39.9    -0.7    261  1.3
  8750   -6.0  21.2   020    9    5   9.6   5.3    4.3  39.8    -0.7    234  1.2
  8500   -5.4  22.3   020    7    4   8.6   4.7    4.2  39.6    -0.8    207  1.1
  8250   -4.7  23.5   025    5    3   8.9   4.9    4.2  39.5    -0.9    180  0.9
  8000   -4.1  24.6   030    3    2   8.8   4.8    4.1  39.4    -0.9    153  0.8
  7750   -3.4  25.9   030    2    1   8.9   4.9    4.1  39.3    -1.0    126  0.6
  7500   -2.8  27.0   035    2    1   8.9   4.9    4.0  39.2    -1.1     99  0.5
  7250   -2.1  28.2   035    1    1   8.8   4.9    3.9  39.1    -1.2     72  0.4
  7000   -1.4  29.5   040    1    1   8.9   4.9    3.9  39.0    -1.2     45  0.2
  6750   -0.8  30.6   260    1    0   8.6   4.7    3.8  38.8    -1.3     18  0.1
  6500   -0.1  31.8   245    2    1  10.0   5.5    3.7  38.7    -1.4      M    M
  6250    0.5  32.9   240    4    2   4.8   2.6    3.6  38.6    -1.5      M    M
  6000    0.3  32.5   240    6    3  -9.9  -5.4    2.7  36.9    -2.5      M    M
  5750   -1.4  29.5   225    5    2 -35.5 -19.5    0.4  32.7    -4.9      6  0.0
  5500   -5.1  22.8   200    4    2 -62.0 -34.0   -4.1  24.6    -9.4    111  0.6

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

           02/24/2015 at 0800 MST          |       02/24/2015 at 1100 MST
                                           |
K index... -7.5  LI... +281.6              | K index... -8.1  LI... +282.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.7 -71.9  295  32 17   1.1   0.6 | -57.9 -72.2  295  30 15   0.9   0.5
 45000 -56.0 -68.8  285  34 17   1.3   0.7 | -56.5 -69.7  285  30 15   1.1   0.6
 40000 -57.6 -71.7  295  11  5  -1.2  -0.6 | -57.0 -70.6  295   9  5  -0.4  -0.2
 38000 -57.3 -71.1  040   4  2   3.0   1.6 | -56.7 -70.1  040   3  2   2.1   1.1
 36000 -55.5 -67.9  085  18  9   2.9   1.6 | -55.3 -67.5  090  17  9   2.1   1.1
 34000 -53.5 -64.3  090  31 16   7.2   3.9 | -53.6 -64.5  095  28 14   8.1   4.5
 32000 -49.1 -56.4  090  29 15   7.4   4.1 | -49.1 -56.4  090  26 13   7.5   4.1
 30000 -44.6 -48.3  090  27 14   6.8   3.7 | -44.7 -48.5  090  24 12   6.9   3.8
 29000 -42.7 -44.9  085  28 14   6.7   3.7 | -42.6 -44.7  085  25 13   7.0   3.8
 28000 -40.2 -40.4  080  28 14   6.7   3.7 | -40.5 -40.9  080  26 13   7.0   3.8
 27000 -38.2 -36.8  075  28 15   7.1   3.9 | -38.4 -37.1  075  27 14   7.0   3.9
 26000 -35.8 -32.4  070  30 15   7.9   4.3 | -36.0 -32.8  070  27 14   7.8   4.3
 25000 -33.5 -28.3  070  31 16   7.9   4.3 | -33.7 -28.7  070  28 14   7.8   4.3
 24000 -31.1 -24.0  070  32 17   7.9   4.3 | -31.3 -24.3  070  29 15   7.8   4.3
 23000 -28.8 -19.8  070  30 16   7.6   4.2 | -29.0 -20.2  070  28 14   7.9   4.3
 22000 -26.6 -15.9  070  27 14   7.6   4.2 | -26.6 -15.9  075  27 14   7.9   4.3
 21000 -24.3 -11.7  070  24 13   7.2   4.0 | -24.2 -11.6  075  25 13   7.5   4.1
 20000 -22.3  -8.1  065  21 11   6.9   3.8 | -22.2  -8.0  070  22 12   6.5   3.6
 19500 -21.2  -6.2  065  19 10   6.9   3.8 | -21.3  -6.3  070  21 11   6.6   3.6
 19000 -20.2  -4.4  060  17  9   6.9   3.8 | -20.3  -4.5  070  19 10   6.6   3.6
 18500 -19.2  -2.6  060  15  8   6.8   3.7 | -18.8  -1.8  070  17  9   6.5   3.5
 18000 -18.2  -0.8  060  14  7   6.4   3.5 | -17.9  -0.2  065  16  8   6.4   3.5
 17500 -17.3   0.9  060  13  7   6.4   3.5 | -16.9   1.6  065  14  7   6.5   3.6
 17000 -16.3   2.7  055  12  6   6.5   3.6 | -15.9   3.4  060  13  7   7.0   3.8
 16500 -15.4   4.3  055  11  6   6.5   3.5 | -14.9   5.2  060  13  6   7.0   3.9
 16000 -14.4   6.1  055  10  5   5.8   3.2 | -13.9   7.0  055  12  6   5.8   3.2
 15500 -13.7   7.3  045   9  5   5.1   2.8 | -13.1   8.4  050  11  6   5.8   3.2
 15000 -12.6   9.3  030   9  5   4.5   2.4 | -12.2  10.0  045  11  6   4.6   2.5
 14500 -11.9  10.6  025  10  5   4.4   2.4 | -11.6  11.1  040  12  6   4.1   2.3
 14000 -11.3  11.7  015  11  6   3.7   2.0 | -11.0  12.2  035  12  6   3.7   2.0
 13500 -10.8  12.6  015  12  6   3.3   1.8 | -10.5  13.1  030  13  7   3.3   1.8
 13000 -10.4  13.3  010  14  7   3.6   2.0 | -10.0  14.0  020  13  7   3.2   1.7
 12500  -9.7  14.5  010  14  7   3.9   2.2 |  -9.6  14.7  020  14  7   2.9   1.6
 12000  -9.1  15.6  010  15  8   4.4   2.4 |  -9.2  15.4  015  15  8   3.6   2.0
 11500  -8.4  16.9  010  15  8   4.9   2.7 |  -8.4  16.9  015  15  8   5.0   2.7
 11000  -7.7  18.1  010  16  8   5.1   2.8 |  -7.7  18.1  015  16  8   4.8   2.6
 10500  -6.9  19.6  005  14  7   5.4   3.0 |  -7.0  19.4  015  14  7   4.6   2.5
 10250  -6.5  20.3  360  14  7   4.6   2.5 |  -6.6  20.1  015  13  7   4.6   2.5
 10000  -6.2  20.8  360  13  7   2.2   1.2 |  -6.3  20.7  015  12  6   3.2   1.8
  9750  -6.0  21.2  360  12  6   4.0   2.2 |  -6.1  21.0  015  12  6   4.2   2.3
  9500  -5.6  21.9  355  11  6   6.3   3.4 |  -5.6  21.9  015  10  5   6.0   3.3
  9250  -5.2  22.6  355  11  5   5.3   2.9 |  -5.2  22.6  015   9  5   5.4   2.9
  9000  -4.8  23.4  355  10  5   4.5   2.5 |  -4.8  23.4  015   8  4   4.8   2.6
  8750  -4.5  23.9  360   9  5   5.3   2.9 |  -4.5  23.9  015   7  4   5.8   3.2
  8500  -4.0  24.8  005   8  4   6.1   3.3 |  -4.0  24.8  020   7  3   6.9   3.8
  8250  -3.6  25.5  010   8  4   6.3   3.5 |  -3.5  25.7  020   6  3   6.4   3.5
  8000  -3.1  26.4  015   7  4   6.8   3.7 |  -3.0  26.6  025   5  3   6.0   3.3
  7750  -2.6  27.3  020   6  3   6.6   3.6 |  -2.5  27.5  025   4  2   6.4   3.5
  7500  -2.1  28.2  025   5  3   6.9   3.8 |  -2.0  28.4  030   3  2   6.9   3.8
  7250  -1.5  29.3  030   4  2   7.3   4.0 |  -1.5  29.3  025   2  1   6.9   3.8
  7000  -1.0  30.2  035   2  1   7.5   4.1 |  -1.0  30.2  000   0  0   6.9   3.8
  6750  -0.4  31.3  000   0  0   7.1   3.9 |  -0.5  31.1  220   1  1   7.4   4.0
  6500  -0.1  31.8  205   2  1  -1.0  -0.6 |   0.0  32.0  220   3  2   5.0   2.8
  6250  -0.6  30.9  215   3  2  -7.8  -4.3 |   0.2  32.4  220   4  2   2.8   1.5
  6000  -1.0  30.2  220   5  3  -2.3  -1.3 |   0.5  32.9  220   4  2   3.7   2.0
  5750  -1.5  29.3  225   6  3 -17.4  -9.5 |   0.7  33.3  220   5  2   2.5   1.4
  5500  -4.6  23.7  215   5  3 -69.8 -38.3 |   0.6  33.1  220   4  2  -4.6  -2.5

           02/24/2015 at 1400 MST          |       02/24/2015 at 1700 MST
                                           |
K index... +2.6  LI... +280.1              | K index... -0.3  LI... +279.0
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... -0.1
                                           |
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 -57.7 -71.9  300  28 14   1.0   0.5 | -57.2 -71.0  290  25 13   1.0   0.6
 45000 -56.2 -69.2  285  29 15   1.1   0.6 | -55.7 -68.3  285  28 14   1.3   0.7
 40000 -56.9 -70.4  320  10  5  -0.6  -0.3 | -58.3 -72.9  345  22 12  -1.9  -1.1
 38000 -56.6 -69.9  020   9  5   2.1   1.2 | -58.4 -73.1  005  26 13   3.8   2.1
 36000 -55.3 -67.5  050  15  8   2.1   1.2 | -56.1 -69.0  010  27 14   3.9   2.1
 34000 -53.8 -64.8  065  23 12   6.4   3.5 | -53.3 -63.9  015  29 15   7.2   4.0
 32000 -49.4 -56.9  060  22 11   7.4   4.1 | -49.0 -56.2  020  30 15   7.1   3.9
 30000 -45.0 -49.0  060  21 11   7.0   3.9 | -44.7 -48.5  020  31 16   6.9   3.8
 29000 -42.9 -45.2  055  22 11   6.9   3.8 | -42.6 -44.7  025  30 16   6.9   3.8
 28000 -40.4 -40.7  055  23 12   6.9   3.8 | -40.6 -41.1  025  30 15   6.9   3.8
 27000 -38.3 -36.9  055  24 12   7.1   3.9 | -38.5 -37.3  025  29 15   6.8   3.7
 26000 -36.0 -32.8  055  25 13   7.9   4.3 | -36.3 -33.3  030  27 14   7.7   4.2
 25000 -33.7 -28.7  060  25 13   7.9   4.3 | -34.0 -29.2  030  25 13   7.7   4.2
 24000 -31.3 -24.3  060  26 13   7.8   4.3 | -31.6 -24.9  035  22 12   7.7   4.2
 23000 -28.9 -20.0  065  25 13   8.3   4.6 | -29.2 -20.6  040  21 11   8.2   4.5
 22000 -26.4 -15.5  065  24 12   8.3   4.6 | -26.8 -16.2  040  20 10   8.2   4.5
 21000 -23.9 -11.0  065  22 12   7.9   4.3 | -24.4 -11.9  040  19 10   8.1   4.4
 20000 -21.8  -7.2  065  20 10   7.0   3.9 | -22.1  -7.8  040  17  9   7.3   4.0
 19500 -20.7  -5.3  065  19 10   7.0   3.9 | -21.0  -5.8  035  17  8   7.3   4.0
 19000 -19.7  -3.5  065  18  9   7.0   3.9 | -19.9  -3.8  035  16  8   7.3   4.0
 18500 -18.6  -1.5  065  17  9   7.0   3.8 | -18.8  -1.8  035  15  8   7.3   4.0
 18000 -17.6   0.3  065  16  8   6.2   3.4 | -17.3   0.9  030  14  7   6.8   3.7
 17500 -16.7   1.9  060  15  7   6.3   3.4 | -16.3   2.7  025  14  7   6.8   3.7
 17000 -15.8   3.6  055  14  7   5.7   3.1 | -15.3   4.5  020  14  7   6.0   3.3
 16500 -15.0   5.0  050  12  6   5.7   3.1 | -14.4   6.1  015  13  7   6.1   3.3
 16000 -14.2   6.4  045  11  6   6.0   3.3 | -13.5   7.7  010  13  7   5.5   3.0
 15500 -13.3   8.1  040  11  6   6.5   3.5 | -12.8   9.0  005  13  7   5.4   3.0
 15000 -11.9  10.6  035  11  5   5.6   3.1 | -12.0  10.4  360  13  7   5.4   3.0
 14500 -11.2  11.8  030  10  5   5.1   2.8 | -11.2  11.8  355  13  7   5.4   2.9
 14000 -10.4  13.3  020  10  5   4.1   2.2 | -10.4  13.3  345  13  7   5.0   2.8
 13500 -10.0  14.0  015  10  5   2.7   1.5 |  -9.8  14.4  340  14  7   3.8   2.1
 13000  -9.6  14.7  005  10  5   2.7   1.5 |  -9.3  15.3  340  14  7   4.0   2.2
 12500  -9.2  15.4  360  10  5   2.7   1.5 |  -8.7  16.3  335  14  7   4.3   2.3
 12000  -8.8  16.2  360  10  5   3.2   1.8 |  -8.1  17.4  335  15  8   4.4   2.4
 11500  -8.2  17.2  360  10  5   4.7   2.6 |  -7.3  18.9  335  14  7   6.1   3.4
 11000  -7.5  18.5  005  10  5   5.0   2.7 |  -6.4  20.5  330  13  6   6.0   3.3
 10500  -6.7  19.9  005   8  4   5.6   3.1 |  -5.6  21.9  325  11  6   5.7   3.1
 10250  -6.2  20.8  005   8  4   6.3   3.5 |  -5.1  22.8  325  10  5   4.9   2.7
 10000  -5.8  21.6  005   7  4   3.7   2.0 |  -4.7  23.5  320   9  5   7.9   4.3
  9750  -5.5  22.1  360   6  3   4.0   2.2 |  -4.0  24.8  315   8  4   8.5   4.7
  9500  -5.0  23.0  355   5  2   7.0   3.8 |  -3.4  25.9  310   7  4   6.0   3.3
  9250  -4.5  23.9  340   3  2   6.2   3.4 |  -2.9  26.8  300   6  3   7.0   3.8
  9000  -4.0  24.8  320   3  1   5.6   3.1 |  -2.4  27.7  295   6  3   6.0   3.3
  8750  -3.6  25.5  300   2  1   5.7   3.1 |  -1.9  28.6  285   5  3   5.7   3.1
  8500  -3.2  26.2  265   2  1   6.1   3.4 |  -1.5  29.3  275   5  2   6.3   3.5
  8250  -2.7  27.1  235   2  1   6.2   3.4 |  -1.0  30.2  265   4  2   6.1   3.4
  8000  -2.2  28.0  220   3  1   6.7   3.7 |  -0.5  31.1  245   4  2   5.8   3.2
  7750  -1.7  28.9  205   3  2   6.4   3.5 |  -0.1  31.8  230   5  2   5.1   2.8
  7500  -1.3  29.7  195   4  2   6.1   3.3 |   0.3  32.5  215   5  3   4.5   2.5
  7250  -0.8  30.6  190   5  2   6.3   3.4 |   0.6  33.1  205   6  3   5.1   2.8
  7000  -0.3  31.5  190   6  3   5.9   3.3 |   1.1  34.0  195   6  3   5.6   3.1
  6750   0.1  32.2  190   7  4   7.2   3.9 |   1.5  34.7  190   7  4   5.4   3.0
  6500   0.7  33.3  190   8  4   7.1   3.9 |   1.9  35.4  185   8  4   4.8   2.6
  6250   1.1  34.0  195   9  4   5.3   2.9 |   2.1  35.8  185   9  4   3.5   1.9
  6000   1.5  34.7  195   9  5   5.9   3.2 |   2.3  36.1  180   9  5   3.4   1.8
  5750   1.8  35.2  195   9  5   4.8   2.6 |   2.5  36.5  180   9  5   3.4   1.9
  5500   2.0  35.6  195   8  4  -1.5  -0.8 |   2.4  36.3  175   9  5  -6.7  -3.7
________________________________________________________________________________

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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