Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 300117
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1916 MDT Friday, April 29, 2016

This forecast is for Saturday, April 30, 2016:

If the trigger temperature of 41.9 F/5.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9340 ft MSL (4033 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 1500 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................. 7042 ft MSL (1736 ft AGL)
Thermal soaring outlook for Sunday 05/01....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 11948 ft MSL (6641 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 16621 ft MSL (11314 ft AGL)
Wave soaring outlook for Sunday 05/01.......... Poor

Remarks...

Sunrise/Sunset.................... 06:00:39 / 19:52:22 MDT
Total possible sunshine........... 13 hr 51 min 44 sec (831 min 44 sec)
Altitude of sun at 12:56:41 MDT... 65.31 degrees

Upper air data from numerical model forecast valid on 04/30/2016 at 0600 MDT

Freezing level.................. 5480 ft MSL (173 ft AGL)
Convective condensation level... 8611 ft MSL (3304 ft AGL)
Lifted condensation level....... 9025 ft MSL (3718 ft AGL)
Lifted index.................... +8.4
K index......................... +13.0

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  -53.7 -64.7   240   17    9   1.8   1.0      M     M       M      M    M
 45000  -50.9 -59.6   240   15    8   1.8   1.0      M     M       M      M    M
 40000  -50.9 -59.6   245   11    6  -0.1  -0.0      M     M       M      M    M
 38000  -51.2 -60.2   255    9    5  -1.8  -1.0      M     M       M      M    M
 36000  -52.4 -62.3   305    9    5  -1.9  -1.0      M     M       M      M    M
 34000  -53.5 -64.3   335   14    7  -2.7  -1.5      M     M       M      M    M
 32000  -51.5 -60.7   330   18    9   4.1   2.3      M     M       M      M    M
 30000  -48.6 -55.5   325   22   11   7.6   4.2   27.1  80.8    16.1      M    M
 29000  -45.8 -50.4   325   22   11   9.2   5.0   26.7  80.1    16.0      M    M
 28000  -43.1 -45.6   325   22   11   9.2   5.0   26.5  79.6    16.0      M    M
 27000  -40.3 -40.5   330   22   11   9.2   5.1   26.3  79.4    16.1      M    M
 26000  -37.7 -35.9   330   20   11   8.6   4.7   26.0  78.7    16.0      M    M
 25000  -35.1 -31.2   335   18    9   8.6   4.7   25.5  77.9    15.8      M    M
 24000  -32.6 -26.7   345   16    8   8.6   4.7   25.1  77.2    15.7      M    M
 23000  -30.1 -22.2   350   16    8   7.9   4.3   24.6  76.2    15.5      M    M
 22000  -27.8 -18.0   350   15    8   7.9   4.3   23.8  74.9    15.0      M    M
 21000  -25.4 -13.7   350   15    8   8.1   4.4   23.2  73.8    14.7      M    M
 20000  -23.4 -10.1   340   16    8   6.2   3.4   22.1  71.8    13.9      M    M
 19500  -22.5  -8.5   335   17    9   6.2   3.4   21.5  70.7    13.4      M    M
 19000  -21.6  -6.9   335   18    9   6.2   3.4   20.9  69.5    12.9      M    M
 18500  -20.7  -5.3   330   19   10   6.2   3.4   20.3  68.5    12.5      M    M
 18000  -19.8  -3.6   325   20   10   6.1   3.3   19.7  67.5    12.0      M    M
 17500  -18.9  -2.0   325   19   10   6.1   3.3   19.0  66.3    11.5      M    M
 17000  -18.0  -0.4   325   19   10   6.1   3.3   18.4  65.2    11.0      M    M
 16500  -17.1   1.2   325   19   10   6.2   3.4   17.8  64.0    10.5      M    M
 16000  -15.7   3.7   325   17    9   6.0   3.3   16.9  62.4     9.8      M    M
 15500  -14.9   5.2   330   17    9   5.9   3.2   16.2  61.2     9.3      M    M
 15000  -14.0   6.8   330   16    8   5.8   3.2   15.6  60.1     8.7      M    M
 14500  -13.2   8.2   335   16    8   5.1   2.8   14.9  58.7     8.1      M    M
 14000  -12.5   9.5   340   15    8   5.2   2.9   14.1  57.4     7.4      M    M
 13500  -11.8  10.8   340   15    8   4.0   2.2   13.3  55.9     6.7      M    M
 13000  -11.2  11.8   345   15    8   4.3   2.3   12.3  54.2     5.9      M    M
 12500  -10.6  12.9   350   15    8   2.8   1.6   11.3  52.4     5.0      M    M
 12000  -10.2  13.6   355   15    8   2.8   1.5   10.2  50.4     4.0      M    M
 11500   -9.7  14.5   360   15    8   4.7   2.6    9.3  48.7     3.1      M    M
 11000   -9.0  15.8   360   16    8   4.6   2.5    8.4  47.2     2.3      M    M
 10500   -8.3  17.1   360   16    8   4.8   2.6    7.6  45.7     1.5      M    M
 10250   -8.0  17.6   360   16    8   4.2   2.3    7.2  45.0     1.1      M    M
 10000   -7.6  18.3   360   16    8   6.2   3.4    6.8  44.3     0.8      M    M
  9750   -7.1  19.2   360   16    8   6.7   3.7    6.6  43.9     0.6      M    M
  9500   -6.7  19.9   355   16    8   5.0   2.7    6.3  43.3     0.2      M    M
  9250   -6.3  20.7   355   15    8   5.2   2.9    5.9  42.7    -0.1    274  1.4
  9000   -5.9  21.4   350   15    8   5.9   3.3    5.6  42.1    -0.5    255  1.3
  8750   -5.5  22.1   350   15    8   5.8   3.2    5.3  41.6    -0.8    234  1.2
  8500   -5.1  22.8   350   15    8   4.9   2.7    4.9  40.9    -1.1    216  1.1
  8250   -4.8  23.4   345   15    7   4.9   2.7    4.6  40.3    -1.5    198  1.0
  8000   -4.4  24.1   345   14    7   6.4   3.5    4.2  39.6    -1.8    179  0.9
  7750   -3.9  25.0   345   14    7   6.8   3.7    4.0  39.3    -2.1    156  0.8
  7500   -3.5  25.7   350   13    7   5.7   3.1    3.7  38.7    -2.4    136  0.7
  7250   -3.0  26.6   350   13    7   5.9   3.2    3.4  38.2    -2.7    116  0.6
  7000   -2.6  27.3   355   13    6   5.8   3.2    3.1  37.7    -3.0     96  0.5
  6750   -2.2  28.0   355   13    7   5.5   3.0    2.8  37.1    -3.3     77  0.4
  6500   -1.8  28.8   355   13    7   5.1   2.8    2.5  36.5    -3.7     58  0.3
  6250   -1.5  29.3   355   13    7   5.0   2.7    2.1  35.9    -4.1     39  0.2
  6000   -1.1  30.0   345   12    6   4.6   2.5    1.8  35.2    -4.5     22  0.1
  5750   -0.8  30.6   335   10    5   5.4   3.0    1.4  34.5    -4.9      4  0.0
  5500   -0.3  31.5   330    8    4   9.1   5.0    1.2  34.1    -5.1      M    M

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

           04/30/2016 at 0900 MDT          |       04/30/2016 at 1200 MDT
                                           |
K index... +11.6  LI... +6.2               | K index... +14.2  LI... +4.8
CAPE... 0.0  CIN... -0.3                   | CAPE... +41.1  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 -54.1 -65.4  245  17  9   1.2   0.7 | -54.1 -65.4  240  13  7   1.0   0.6
 45000 -52.2 -62.0  245  15  8   1.2   0.6 | -52.4 -62.3  255  12  6   1.0   0.6
 40000 -51.3 -60.3  265  11  5   0.6   0.3 | -51.9 -61.4  265  12  6   0.3   0.2
 38000 -51.4 -60.5  285   9  5  -2.0  -1.1 | -52.1 -61.8  275  10  5  -1.9  -1.0
 36000 -52.7 -62.9  325   9  4  -2.1  -1.1 | -53.3 -63.9  335   6  3  -1.9  -1.1
 34000 -53.9 -65.0  355  12  6  -2.6  -1.4 | -54.4 -65.9  020  12  6  -1.8  -1.0
 32000 -51.7 -61.1  025  12  6   4.5   2.5 | -51.4 -60.5  050  24 12   5.0   2.7
 30000 -48.5 -55.3  050  15  8   7.8   4.3 | -48.2 -54.8  055  34 17   8.7   4.8
 29000 -45.9 -50.6  050  16  8   8.7   4.8 | -45.5 -49.9  050  27 14   9.1   5.0
 28000 -43.3 -45.9  045  18  9   8.7   4.8 | -42.8 -45.0  040  21 11   9.1   5.0
 27000 -40.7 -41.3  045  19 10   8.7   4.8 | -40.0 -40.0  025  16  8   9.2   5.0
 26000 -38.0 -36.4  045  18  9   9.2   5.0 | -37.4 -35.3  010  14  7   8.6   4.7
 25000 -35.3 -31.5  040  15  8   9.2   5.0 | -34.9 -30.8  355  14  7   8.6   4.7
 24000 -32.5 -26.5  035  12  6   9.2   5.0 | -32.3 -26.1  340  15  8   8.6   4.7
 23000 -30.1 -22.2  030  11  6   7.7   4.2 | -30.0 -22.0  340  15  8   7.1   3.9
 22000 -27.8 -18.0  020  11  5   7.6   4.2 | -27.9 -18.2  345  14  7   7.1   3.9
 21000 -25.5 -13.9  010  11  5   7.7   4.2 | -25.8 -14.4  350  13  7   7.1   3.9
 20000 -23.4 -10.1  360  11  6   6.9   3.8 | -23.6 -10.5  355  12  6   7.3   4.0
 19500 -22.4  -8.3  360  11  6   6.9   3.8 | -22.5  -8.5  355  12  6   7.3   4.0
 19000 -21.4  -6.5  355  11  6   7.0   3.8 | -21.4  -6.5  355  11  6   7.3   4.0
 18500 -20.4  -4.7  350  12  6   7.1   3.9 | -20.3  -4.5  360  11  6   7.5   4.1
 18000 -19.4  -2.9  350  12  6   6.1   3.4 | -19.4  -2.9  360  11  6   5.6   3.1
 17500 -18.5  -1.3  345  13  7   6.1   3.3 | -18.5  -1.3  005  11  6   5.7   3.1
 17000 -17.6   0.3  345  14  7   6.0   3.3 | -17.7   0.1  005  11  6   6.3   3.4
 16500 -16.8   1.8  345  15  8   5.8   3.2 | -16.2   2.8  010  11  6   7.1   3.9
 16000 -15.5   4.1  345  15  8   5.6   3.1 | -15.2   4.6  010  11  6   5.5   3.0
 15500 -14.7   5.5  345  15  8   5.5   3.0 | -14.5   5.9  010  11  6   4.8   2.7
 15000 -13.9   7.0  350  15  8   5.4   2.9 | -13.8   7.2  010  11  6   4.3   2.4
 14500 -13.1   8.4  350  14  7   5.0   2.8 | -13.3   8.1  010  11  6   3.4   1.9
 14000 -12.4   9.7  355  14  7   5.1   2.8 | -12.8   9.0  005  11  6   3.6   2.0
 13500 -11.6  11.1  360  13  7   5.9   3.2 | -12.2  10.0  360  12  6   4.7   2.6
 13000 -10.7  12.7  005  13  7   5.9   3.2 | -11.5  11.3  360  13  7   4.7   2.6
 12500  -9.9  14.2  005  13  7   4.5   2.4 | -10.8  12.6  355  14  7   5.2   2.9
 12000  -9.3  15.3  360  14  7   4.8   2.7 | -10.0  14.0  355  15  8   5.2   2.8
 11500  -8.9  16.0  360  14  7   0.8   0.4 |  -9.2  15.4  355  16  8   5.3   2.9
 11000  -8.7  16.3  355  16  8   1.1   0.6 |  -8.5  16.7  355  18  9   5.2   2.8
 10500  -8.3  17.1  360  17  9   3.9   2.1 |  -7.8  18.0  360  20 10   4.2   2.3
 10250  -8.1  17.4  360  18  9   3.2   1.8 |  -7.5  18.5  360  21 11   3.6   2.0
 10000  -7.8  18.0  360  19 10   4.7   2.6 |  -7.2  19.0  005  22 12   6.4   3.5
  9750  -7.4  18.7  360  19 10   6.2   3.4 |  -6.6  20.1  005  23 12   6.9   3.8
  9500  -7.0  19.4  360  20 10   5.8   3.2 |  -6.3  20.7  005  24 12   4.5   2.5
  9250  -6.6  20.1  360  20 10   6.0   3.3 |  -5.9  21.4  010  24 13   5.1   2.8
  9000  -6.1  21.0  360  20 10   5.5   3.0 |  -5.5  22.1  010  25 13   5.4   3.0
  8750  -5.7  21.7  360  20 10   5.7   3.1 |  -5.1  22.8  010  23 12   6.8   3.7
  8500  -5.3  22.5  355  19 10   6.3   3.5 |  -4.6  23.7  010  21 11   7.1   3.9
  8250  -4.8  23.4  355  19 10   6.2   3.4 |  -4.1  24.6  005  20 10   7.4   4.1
  8000  -4.4  24.1  355  18  9   5.1   2.8 |  -3.5  25.7  005  18  9   9.1   5.0
  7750  -4.1  24.6  355  18  9   4.9   2.7 |  -2.8  27.0  005  17  9   9.6   5.3
  7500  -3.7  25.3  355  17  9   5.5   3.0 |  -2.1  28.2  005  15  8   8.9   4.9
  7250  -3.3  26.1  355  17  9   5.8   3.2 |  -1.5  29.3  360  14  7   9.9   5.4
  7000  -2.8  27.0  350  15  8   6.8   3.7 |  -0.7  30.7  360  14  7  11.2   6.1
  6750  -2.4  27.7  350  13  7   6.0   3.3 |   0.1  32.2  360  13  7  10.0   5.5
  6500  -2.0  28.4  345  12  6   6.4   3.5 |   0.8  33.4  360  13  7   9.8   5.4
  6250  -1.4  29.5  345  10  5  10.4   5.7 |   1.6  34.9  360  13  7  11.3   6.2
  6000  -0.5  31.1  340   9  5  12.9   7.1 |   2.5  36.5  360  12  6  11.7   6.4
  5750   0.4  32.7  340   8  4  10.6   5.8 |   3.3  37.9  360  12  6  11.5   6.3
  5500   1.1  34.0  340   8  4  11.1   6.1 |   4.3  39.7  360  12  6  16.1   8.9

           04/30/2016 at 1500 MDT          |       04/30/2016 at 1800 MDT
                                           |
K index... +17.2  LI... +3.2               | K index... +15.7  LI... +3.9
CAPE... +60.9  CIN... M                    | CAPE... +39.8  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 -54.0 -65.2  235  11  6   1.2   0.7 | -54.3 -65.7  240  11  6   0.8   0.4
 45000 -52.1 -61.8  240  12  6   1.1   0.6 | -53.0 -63.4  250  14  7   0.8   0.4
 40000 -52.0 -61.6  270  16  8   0.0   0.0 | -52.6 -62.7  280  16  8   0.2   0.1
 38000 -52.3 -62.1  280  15  8  -1.7  -0.9 | -52.8 -63.0  285  17  9  -1.2  -0.6
 36000 -53.3 -63.9  310  11  5  -1.7  -0.9 | -53.5 -64.3  290  16  8  -1.2  -0.6
 34000 -54.4 -65.9  355  11  6  -1.1  -0.6 | -54.2 -65.6  295  15  8   0.2   0.1
 32000 -51.2 -60.2  010  15  8   5.2   2.9 | -51.1 -60.0  305  17  9   4.9   2.7
 30000 -47.8 -54.0  020  18  9   9.0   4.9 | -47.9 -54.2  310  19 10   9.3   5.1
 29000 -45.1 -49.2  010  17  9   9.2   5.0 | -45.2 -49.4  315  19 10   8.9   4.9
 28000 -42.4 -44.3  360  15  8   9.2   5.0 | -42.5 -44.5  315  18  9   8.9   4.9
 27000 -39.6 -39.3  345  15  8   9.3   5.1 | -39.9 -39.8  315  18  9   9.0   4.9
 26000 -37.1 -34.8  340  15  8   8.0   4.4 | -37.3 -35.1  320  17  9   8.3   4.6
 25000 -34.8 -30.6  335  15  8   8.0   4.4 | -34.8 -30.6  320  16  8   8.3   4.6
 24000 -32.4 -26.3  330  16  8   8.0   4.4 | -32.4 -26.3  325  15  8   8.4   4.6
 23000 -30.1 -22.2  330  16  8   7.2   4.0 | -30.1 -22.2  330  15  8   7.2   3.9
 22000 -28.0 -18.4  330  15  8   7.2   4.0 | -28.0 -18.4  330  15  8   7.2   3.9
 21000 -25.8 -14.4  330  14  7   7.2   4.0 | -25.8 -14.4  330  15  8   7.2   4.0
 20000 -23.7 -10.7  335  13  7   7.2   4.0 | -23.6 -10.5  330  15  8   7.6   4.2
 19500 -22.6  -8.7  335  13  7   7.2   4.0 | -22.5  -8.5  335  15  8   7.6   4.2
 19000 -21.6  -6.9  340  13  7   7.2   4.0 | -21.3  -6.3  335  16  8   7.6   4.2
 18500 -20.5  -4.9  340  13  7   7.3   4.0 | -20.2  -4.4  340  16  8   7.6   4.2
 18000 -19.5  -3.1  340  13  7   6.1   3.3 | -19.1  -2.4  340  16  8   7.2   4.0
 17500 -18.6  -1.5  340  14  7   6.1   3.4 | -18.1  -0.6  345  16  8   7.2   4.0
 17000 -17.4   0.7  345  14  7   4.2   2.3 | -16.4   2.5  345  17  9   8.0   4.4
 16500 -16.7   1.9  345  14  7   4.4   2.4 | -15.2   4.6  345  17  9   8.3   4.5
 16000 -16.1   3.0  345  14  7   5.2   2.8 | -14.3   6.3  345  18  9   3.1   1.7
 15500 -15.3   4.5  340  14  7   5.4   3.0 | -13.9   7.0  345  18  9   2.6   1.4
 15000 -14.5   5.9  340  14  7   5.8   3.2 | -13.6   7.5  340  19 10   2.9   1.6
 14500 -13.5   7.7  335  15  8   6.2   3.4 | -13.1   8.4  340  19 10   3.2   1.8
 14000 -12.6   9.3  330  16  8   6.1   3.4 | -12.7   9.1  340  20 10   4.2   2.3
 13500 -11.8  10.8  335  16  8   5.8   3.2 | -11.9  10.6  340  20 10   5.7   3.2
 13000 -10.9  12.4  335  17  9   5.8   3.2 | -11.0  12.2  345  21 11   5.8   3.2
 12500 -10.1  13.8  340  18  9   5.6   3.1 | -10.1  13.8  350  21 11   6.1   3.3
 12000  -9.3  15.3  345  19 10   5.6   3.1 |  -9.3  15.3  355  22 11   5.9   3.2
 11500  -8.5  16.7  355  20 10   5.3   2.9 |  -8.4  16.9  360  22 11   5.5   3.0
 11000  -7.7  18.1  005  22 11   5.2   2.9 |  -7.6  18.3  005  21 11   5.6   3.1
 10500  -7.0  19.4  010  22 11   4.9   2.7 |  -6.8  19.8  010  21 11   5.7   3.1
 10250  -6.6  20.1  015  22 11   4.2   2.3 |  -6.4  20.5  015  21 11   6.5   3.6
 10000  -6.3  20.7  015  22 11   6.8   3.7 |  -5.9  21.4  020  20 11   3.5   1.9
  9750  -5.7  21.7  020  22 11   7.5   4.1 |  -5.8  21.6  020  20 10   4.1   2.3
  9500  -5.3  22.5  020  21 11   5.4   3.0 |  -5.3  22.5  025  20 10   7.6   4.2
  9250  -4.8  23.4  020  21 11   6.0   3.3 |  -4.8  23.4  025  20 10   6.5   3.5
  9000  -4.4  24.1  020  20 10   5.6   3.0 |  -4.3  24.3  030  20 10   5.0   2.8
  8750  -4.0  24.8  020  19 10   7.0   3.8 |  -4.0  24.8  030  20 10   5.5   3.0
  8500  -3.4  25.9  020  18 10   8.0   4.4 |  -3.5  25.7  030  20 10   6.7   3.7
  8250  -2.9  26.8  020  18  9   8.2   4.5 |  -3.0  26.6  025  20 10   7.0   3.8
  8000  -2.2  28.0  020  17  9   9.9   5.4 |  -2.5  27.5  025  19 10   8.1   4.5
  7750  -1.5  29.3  020  16  8   9.8   5.4 |  -1.9  28.6  020  17  9   8.4   4.6
  7500  -0.8  30.6  020  15  8   8.7   4.8 |  -1.3  29.7  020  16  8   8.5   4.7
  7250  -0.2  31.6  015  15  8  10.0   5.5 |  -0.7  30.7  020  15  8   9.4   5.1
  7000   0.6  33.1  020  15  7  11.2   6.1 |   0.1  32.2  015  15  8  10.1   5.6
  6750   1.4  34.5  020  14  7  10.1   5.6 |   0.8  33.4  015  15  7   9.5   5.2
  6500   2.2  36.0  020  14  7  10.0   5.5 |   1.5  34.7  015  14  7   9.9   5.5
  6250   3.0  37.4  020  14  7  11.2   6.1 |   2.3  36.1  015  14  7  10.9   6.0
  6000   3.8  38.8  015  13  7  11.3   6.2 |   3.1  37.6  015  14  7  10.6   5.8
  5750   4.6  40.3  015  13  7  11.4   6.3 |   3.9  39.0  015  13  7  11.2   6.1
  5500   5.6  42.1  020  13  7  16.2   8.9 |   4.8  40.6  015  13  7  14.5   8.0
________________________________________________________________________________

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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