Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201259
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0659 MDT Sunday, April 20, 2014

This forecast is for Sunday, April 20, 2014:

If the trigger temperature of 64.8 F/18.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 585 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14490 ft MSL (9205 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11140 ft MSL (5855 ft AGL)
Thermal soaring outlook for Monday 04/21....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 14642 ft MSL (9357 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 15380 ft MSL (10095 ft AGL)
Wave soaring outlook for Monday 04/21.......... Poor

Remarks... Upper trough passes over the region today.

Sunrise/Sunset.................... 06:14:41 / 19:41:47 MDT
Total possible sunshine........... 13 hr 27 min 7 sec (807 min 7 sec)
Altitude of sun at 12:58:24 MDT... 61.92 degrees

Upper air data from rawinsonde observation taken on 04/20/2014 at 0600 MDT

Freezing level.................. 11844 ft MSL (6559 ft AGL)
Convective condensation level... 14040 ft MSL (8755 ft AGL)
Lifted condensation level....... 14415 ft MSL (9130 ft AGL)
Lifted index.................... -0.9
K index......................... +18.3

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  -60.3 -76.5   290   26   13  -3.3  -1.8   98.8 209.9    43.8      M    M
 45000  -55.7 -68.3   260   22   11   2.5   1.4   80.7 177.2    35.9      M    M
 40000  -61.2 -78.2   265   17    9  -6.5  -3.6   49.0 120.3    17.7      M    M
 38000  -61.7 -79.1   255    8    4   5.5   3.0   39.4 103.0    11.7      M    M
 36000  -58.5 -73.3   240   22   11   6.9   3.8   35.5  96.0     9.3      M    M
 34000  -53.5 -64.3   220   21   11   9.8   5.4   34.3  93.8     8.6      M    M
 32000  -47.8 -54.0   225   20   10   8.6   4.7   34.1  93.4     8.7      M    M
 30000  -41.8 -43.2   240   17    9   9.5   5.2   33.4  92.0     8.4      M    M
 29000  -38.9 -38.0   235   16    8   9.5   5.2   33.2  91.7     8.4      M    M
 28000  -36.1 -33.0   225   15    8   8.7   4.8   33.1  91.5     8.4      M    M
 27000  -33.6 -28.5   220   15    8   6.6   3.6   32.5  90.5     8.1      M    M
 26000  -31.5 -24.7   210   15    8   8.1   4.5   31.6  88.9     7.4      M    M
 25000  -28.8 -19.8   205   15    8   8.1   4.4   31.3  88.4     7.3      M    M
 24000  -26.3 -15.3   210   15    8   7.9   4.3   30.7  87.3     6.9      M    M
 23000  -23.9 -11.0   215   13    7   7.7   4.2   30.1  86.2     6.4      M    M
 22000  -22.4  -8.3   225   12    6   6.3   3.5   28.6  83.4     5.1      M    M
 21000  -19.7  -3.5   235   11    6   8.7   4.8   28.2  82.8     4.9      M    M
 20000  -17.6   0.3   245   10    5   9.1   5.0   27.4  81.3     4.2      M    M
 19500  -16.2   2.8   245    9    5   9.4   5.2   27.3  81.1     4.1      M    M
 19000  -14.8   5.4   250    8    4   9.6   5.3   27.2  81.0     4.1      M    M
 18500  -13.5   7.7   250    7    3   7.9   4.3   27.0  80.7     3.9      M    M
 18000  -12.2  10.0   250    6    3   6.8   3.7   26.8  80.3     3.8      M    M
 17500  -11.1  12.0   250    6    3   9.0   5.0   26.4  79.4     3.4      M    M
 17000   -9.9  14.2   250    5    3   7.0   3.9   26.2  79.2     3.3      M    M
 16500   -9.0  15.8   255    5    2   5.5   3.0   25.5  77.9     2.6      M    M
 16000   -8.2  17.2   255    4    2   7.0   3.8   24.9  76.8     2.1      M    M
 15500   -6.5  20.3   285    3    2   8.7   4.8   24.4  75.9     1.6      M    M
 15000   -5.6  21.9   320    3    2   2.2   1.2   23.7  74.7     1.0      M    M
 14500   -5.4  22.3   345    4    2   3.1   1.7   22.4  72.4    -0.2    780  4.0
 14000   -4.4  24.1   355    5    3   7.6   4.2   21.8  71.3    -0.8    738  3.8
 13500   -3.3  26.1   355    6    3   7.4   4.1   21.4  70.6    -1.2    690  3.5
 13000   -2.2  28.0   355    7    4   7.6   4.2   21.1  69.9    -1.5    642  3.3
 12500   -1.3  29.7   355    8    4   6.6   3.6   20.6  69.0    -2.0    599  3.0
 12000   -0.2  31.6   355    9    5   7.6   4.2   20.2  68.4    -2.4    552  2.8
 11500    0.9  33.6   355    7    4   7.7   4.2   19.9  67.8    -2.8    504  2.6
 11000    2.0  35.6   360    6    3   8.7   4.8   19.6  67.3    -3.1    455  2.3
 10500    3.4  38.1   005    4    2   9.1   5.0   19.5  67.1    -3.3    400  2.0
 10250    4.0  39.2   010    3    2   8.7   4.8   19.4  67.0    -3.3    373  1.9
 10000    4.6  40.3   355    3    2   8.0   4.4   19.3  66.8    -3.5    348  1.8
  9750    5.2  41.4   340    4    2   7.9   4.4   19.2  66.5    -3.6    322  1.6
  9500    5.8  42.4   330    5    3   8.0   4.4   19.0  66.3    -3.8    297  1.5
  9250    6.4  43.5   325    6    3   8.0   4.4   18.9  66.1    -3.9    272  1.4
  9000    7.0  44.6   320    7    4   8.0   4.4   18.8  65.8    -4.0    247  1.3
  8750    7.6  45.7   310    7    3   8.0   4.4   18.6  65.6    -4.2    222  1.1
  8500    8.2  46.8   295    6    3   8.0   4.4   18.5  65.3    -4.3    197  1.0
  8250    8.8  47.8   285    7    3   8.0   4.4   18.4  65.1    -4.5    172  0.9
  8000    9.3  48.7   275    7    4   8.0   4.4   18.2  64.8    -4.6    147  0.7
  7750    9.9  49.8   270    7    4   7.8   4.3   18.1  64.6    -4.8    122  0.6
  7500   10.5  50.9   265    7    4   8.4   4.6   17.9  64.3    -5.0     97  0.5
  7250   11.1  52.0   260    8    4   6.4   3.5   17.8  64.1    -5.1     72  0.4
  7000   11.5  52.7   255    8    4   4.0   2.2   17.4  63.4    -5.5     55  0.3
  6750   11.7  53.1   250    9    5   3.7   2.1   17.0  62.6    -6.0     38  0.2
  6500   12.0  53.6   245   10    5   5.5   3.0   16.6  61.8    -6.4     22  0.1
  6250   12.3  54.1   245   11    6  -1.2  -0.6   16.1  61.0    -6.9      6  0.0
  6000   11.8  53.2   240   12    6 -10.4  -5.7   14.8  58.7    -8.2     16  0.1
  5750   10.9  51.6   235   10    5 -10.2  -5.6   13.3  56.0    -9.8     33  0.2
  5500   10.1  50.2   230    8    4 -10.9  -6.0   11.8  53.3   -11.4     51  0.3

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

           04/20/2014 at 0900 MDT          |       04/20/2014 at 1200 MDT
                                           |
K index... +20.3  LI... +1.5               | K index... +19.8  LI... -0.3
CAPE... 0.0  CIN... -0.0                   | CAPE... +44.8  CIN... -18.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.3 -74.7  260  17  9   1.9   1.1 | -60.0 -76.0  265  17  9   1.7   1.0
 45000 -56.7 -70.1  270  16  8  -4.2  -2.3 | -57.7 -71.9  275  14  7  -3.1  -1.7
 40000 -62.1 -79.8  225  23 12  -3.6  -2.0 | -61.8 -79.2  265  16  8  -2.7  -1.5
 38000 -60.3 -76.5  215  23 12   6.5   3.5 | -59.8 -75.6  250  16  8   6.4   3.5
 36000 -56.5 -69.7  210  22 11   6.5   3.5 | -56.0 -68.8  235  18  9   6.4   3.5
 34000 -52.2 -62.0  205  20 10   8.6   4.7 | -51.8 -61.2  230  19 10   8.6   4.7
 32000 -47.0 -52.6  225  17  9   8.6   4.7 | -46.0 -50.8  245  19 10   8.6   4.7
 30000 -41.2 -42.2  245  15  8   8.6   4.7 | -40.8 -41.4  255  19 10   8.4   4.6
 29000 -38.6 -37.5  250  15  7   8.6   4.7 | -38.3 -36.9  260  18  9   8.4   4.6
 28000 -36.1 -33.0  260  14  7   8.6   4.7 | -35.8 -32.4  265  18  9   8.4   4.6
 27000 -33.5 -28.3  265  14  7   8.5   4.7 | -33.2 -27.8  265  16  8   8.5   4.7
 26000 -30.9 -23.6  270  12  6   8.5   4.7 | -30.7 -23.3  270  14  7   8.5   4.7
 25000 -28.4 -19.1  270  11  6   8.6   4.7 | -28.1 -18.6  275  12  6   8.5   4.7
 24000 -25.9 -14.6  280  10  5   7.1   3.9 | -25.7 -14.3  280  11  5   6.8   3.7
 23000 -23.8 -10.8  295  10  5   7.2   3.9 | -23.6 -10.5  300   9  5   7.0   3.8
 22000 -21.6  -6.9  310  10  5   7.2   4.0 | -21.6  -6.9  320   9  5   7.0   3.8
 21000 -19.5  -3.1  325  10  5   6.9   3.8 | -19.6  -3.3  335  10  5   6.5   3.5
 20000 -17.5   0.5  340  10  5   6.9   3.8 | -17.6   0.3  350  11  6   6.5   3.6
 19500 -16.5   2.3  345  10  5   7.0   3.8 | -16.7   1.9  355  11  6   6.6   3.6
 19000 -15.5   4.1  350  10  5   7.1   3.9 | -15.7   3.7  360  12  6   6.7   3.7
 18500 -14.5   5.9  355  10  5   5.6   3.1 | -14.8   5.4  005  12  6   5.3   2.9
 18000 -13.7   7.3  005  10  5   5.7   3.1 | -14.1   6.6  005  12  6   5.5   3.0
 17500 -12.8   9.0  010  10  5   5.6   3.1 | -13.3   8.1  010  11  6   5.7   3.1
 17000 -12.0  10.4  015  10  5   5.4   3.0 | -12.4   9.7  015  10  5   5.9   3.2
 16500 -11.3  11.7  020  10  5   5.5   3.0 | -11.6  11.1  020  10  5   6.0   3.3
 16000 -10.4  13.3  025  10  5   6.9   3.8 | -10.0  14.0  025  10  5   7.2   4.0
 15500  -8.9  16.0  030  10  5   6.9   3.8 |  -9.0  15.8  025  10  5   7.4   4.1
 15000  -7.8  18.0  030  11  5   7.3   4.0 |  -7.9  17.8  020  11  6   7.7   4.2
 14500  -6.8  19.8  030  11  6   7.3   4.0 |  -6.7  19.9  020  12  6   7.7   4.2
 14000  -5.6  21.9  025  11  6   8.2   4.5 |  -5.6  21.9  015  13  7   7.7   4.2
 13500  -4.5  23.9  025  12  6   8.1   4.5 |  -4.5  23.9  015  14  7   7.7   4.2
 13000  -3.3  26.1  020  12  6   8.0   4.4 |  -3.3  26.1  015  15  8   7.8   4.3
 12500  -2.1  28.2  015  12  6   8.1   4.4 |  -2.2  28.0  015  15  8   7.9   4.3
 12000  -0.9  30.4  015  12  6   7.9   4.3 |  -1.0  30.2  015  16  8   7.6   4.1
 11500   0.2  32.4  010  12  6   7.9   4.4 |   0.1  32.2  015  17  9   7.5   4.1
 11000   1.4  34.5  005  13  7   7.9   4.3 |   1.2  34.2  015  17  9   8.5   4.7
 10500   2.5  36.5  360  13  7   8.8   4.8 |   2.5  36.5  015  18  9   9.4   5.2
 10250   3.1  37.6  360  13  7   4.0   2.2 |   3.1  37.6  015  18  9   4.5   2.5
 10000   3.2  37.8  355  14  7   4.9   2.7 |   3.3  37.9  015  18  9   6.2   3.4
  9750   3.9  39.0  355  14  7  10.3   5.7 |   4.1  39.4  015  18  9  12.2   6.7
  9500   4.6  40.3  355  14  7   9.2   5.1 |   4.9  40.8  015  18  9  10.8   5.9
  9250   5.2  41.4  355  14  7   7.2   3.9 |   5.7  42.3  015  18  9   7.6   4.2
  9000   5.7  42.3  350  14  7   6.3   3.4 |   6.1  43.0  015  17  9   6.4   3.5
  8750   6.2  43.2  350  14  7   8.2   4.5 |   6.6  43.9  015  16  8   8.5   4.6
  8500   6.8  44.2  350  14  7   7.6   4.2 |   7.2  45.0  010  14  7   8.1   4.5
  8250   7.3  45.1  345  14  7   6.8   3.7 |   7.8  46.0  010  13  7   8.6   4.7
  8000   7.8  46.0  345  14  7   6.4   3.5 |   8.4  47.1  005  12  6   9.1   5.0
  7750   8.3  46.9  340  14  7   6.8   3.7 |   9.1  48.4  005  11  6   9.5   5.2
  7500   8.8  47.8  340  14  7   6.6   3.6 |   9.8  49.6  005  11  6  10.0   5.5
  7250   9.3  48.7  340  13  7   6.2   3.4 |  10.6  51.1  005  11  6  10.4   5.7
  7000   9.7  49.5  340  13  7   6.2   3.4 |  11.3  52.3  005  11  6  10.4   5.7
  6750  10.1  50.2  340  13  7   5.9   3.2 |  12.1  53.8  005  11  5  10.6   5.8
  6500  10.5  50.9  340  13  7   5.1   2.8 |  12.9  55.2  005  10  5  10.7   5.9
  6250  10.9  51.6  340  11  6   5.5   3.0 |  13.7  56.7  005  10  5  11.2   6.2
  6000  11.2  52.2  340  10  5   3.2   1.7 |  14.5  58.1  005  10  5   9.5   5.2
  5750  11.4  52.5  340   8  4   5.8   3.2 |  15.3  59.5  005  10  5  13.7   7.5
  5500  12.2  54.0  340   7  3  18.7  10.2 |  16.8  62.2  005   9  5  26.3  14.5

           04/20/2014 at 1500 MDT          |       04/20/2014 at 1800 MDT
                                           |
K index... +17.8  LI... -1.2               | K index... +18.9  LI... -1.1
CAPE... +85.8  CIN... -4.4                 | CAPE... +65.6  CIN... -12.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.7 -75.5  260  21 11   1.1   0.6 | -60.2 -76.4  270  23 12   1.3   0.7
 45000 -58.4 -73.1  270  15  8  -2.4  -1.3 | -58.6 -73.5  285  22 11  -2.3  -1.3
 40000 -61.6 -78.9  310  19 10  -2.1  -1.1 | -61.7 -79.1  315  26 14  -2.0  -1.1
 38000 -59.4 -74.9  300  17  9   6.4   3.5 | -59.2 -74.6  315  26 13   7.1   3.9
 36000 -55.6 -68.1  280  16  8   6.4   3.5 | -54.9 -66.8  315  24 12   7.1   3.9
 34000 -51.4 -60.5  265  17  9   8.0   4.4 | -50.5 -58.9  310  22 12   7.8   4.3
 32000 -46.0 -50.8  265  18  9   8.0   4.4 | -45.3 -49.5  305  21 11   7.8   4.3
 30000 -41.0 -41.8  270  18  9   8.4   4.6 | -40.5 -40.9  305  19 10   8.1   4.4
 29000 -38.5 -37.3  275  18  9   8.4   4.6 | -38.1 -36.6  305  19 10   8.1   4.4
 28000 -36.0 -32.8  280  17  9   8.4   4.6 | -35.7 -32.3  305  19 10   8.1   4.4
 27000 -33.5 -28.3  280  17  9   8.1   4.5 | -33.3 -27.9  310  19 10   7.6   4.2
 26000 -31.1 -24.0  285  16  8   8.1   4.5 | -31.1 -24.0  310  19 10   7.6   4.2
 25000 -28.7 -19.7  285  15  8   8.2   4.5 | -28.8 -19.8  310  18  9   7.6   4.2
 24000 -26.3 -15.3  285  14  7   7.1   3.9 | -26.5 -15.7  315  18  9   7.6   4.2
 23000 -24.1 -11.4  295  13  7   7.2   3.9 | -24.3 -11.7  315  18  9   7.6   4.2
 22000 -22.0  -7.6  305  13  7   7.2   4.0 | -22.0  -7.6  315  17  9   7.6   4.2
 21000 -19.9  -3.8  315  13  7   6.5   3.6 | -19.9  -3.8  320  17  9   6.5   3.6
 20000 -18.0  -0.4  325  14  7   6.5   3.6 | -17.9  -0.2  325  18  9   6.5   3.6
 19500 -17.0   1.4  330  15  8   6.5   3.6 | -17.0   1.4  330  18  9   6.5   3.6
 19000 -16.0   3.2  330  16  8   6.6   3.6 | -16.0   3.2  330  19 10   6.6   3.6
 18500 -15.1   4.8  335  16  8   6.4   3.5 | -15.0   5.0  335  19 10   6.5   3.6
 18000 -14.1   6.6  340  17  9   6.4   3.5 | -14.1   6.6  335  19 10   6.5   3.6
 17500 -13.2   8.2  345  17  9   6.9   3.8 | -13.1   8.4  340  19 10   7.2   3.9
 17000 -12.1  10.2  345  17  9   7.2   4.0 | -12.0  10.4  340  19 10   7.6   4.2
 16500 -11.0  12.2  350  17  9   7.3   4.0 | -10.8  12.6  340  20 10   7.6   4.2
 16000  -9.4  15.1  355  17  9   7.6   4.2 |  -9.1  15.6  345  20 10   7.7   4.2
 15500  -8.2  17.2  355  16  8   7.7   4.2 |  -8.0  17.6  345  19 10   7.7   4.2
 15000  -7.1  19.2  355  16  8   7.7   4.2 |  -6.8  19.8  345  19 10   7.8   4.3
 14500  -6.0  21.2  360  17  9   7.7   4.2 |  -5.7  21.7  345  18  9   7.8   4.3
 14000  -4.8  23.4  360  17  9   7.4   4.0 |  -4.6  23.7  350  16  8   7.5   4.1
 13500  -3.8  25.2  005  17  9   7.4   4.0 |  -3.5  25.7  350  14  7   7.6   4.2
 13000  -2.7  27.1  005  17  9   7.9   4.3 |  -2.4  27.7  350  13  7   8.0   4.4
 12500  -1.5  29.3  005  15  8   7.9   4.3 |  -1.3  29.7  350  11  6   7.9   4.3
 12000  -0.4  31.3  005  14  7   7.7   4.2 |  -0.1  31.8  350  10  5   9.0   4.9
 11500   0.6  33.1  005  11  6   7.7   4.2 |   1.2  34.2  350  10  5   8.9   4.9
 11000   1.8  35.2  010  10  5   9.5   5.2 |   2.6  36.7  350  10  5   9.2   5.0
 10500   3.2  37.8  005   9  5   9.9   5.5 |   3.9  39.0  350   9  5   9.8   5.4
 10250   3.8  38.8  005   9  5   5.1   2.8 |   4.6  40.3  350   9  5   5.5   3.0
 10000   4.1  39.4  005   9  5   7.0   3.9 |   4.9  40.8  345   9  5   7.0   3.9
  9750   4.9  40.8  005   9  5  12.8   7.0 |   5.7  42.3  345   9  4  12.0   6.6
  9500   5.8  42.4  005   9  5  11.3   6.2 |   6.5  43.7  345   8  4  10.7   5.9
  9250   6.6  43.9  005   9  5   9.5   5.2 |   7.2  45.0  340   8  4   8.8   4.8
  9000   7.2  45.0  005   9  4   9.4   5.1 |   7.8  46.0  340   8  4   8.6   4.7
  8750   8.0  46.4  005   9  4  11.1   6.1 |   8.6  47.5  335   8  4  10.3   5.7
  8500   8.8  47.8  005   9  4  10.5   5.8 |   9.3  48.7  335   8  4   9.9   5.5
  8250   9.6  49.3  005   8  4  10.5   5.7 |  10.1  50.2  335   8  4  10.5   5.7
  8000  10.4  50.7  005   8  4  10.0   5.5 |  10.8  51.4  335   8  4  10.2   5.6
  7750  11.1  52.0  005   8  4   9.1   5.0 |  11.5  52.7  335   8  4   9.6   5.2
  7500  11.8  53.2  360   8  4   9.8   5.4 |  12.2  54.0  335   8  4   9.6   5.2
  7250  12.6  54.7  360   8  4  10.8   5.9 |  13.0  55.4  330   8  4   9.7   5.3
  7000  13.4  56.1  360   8  4  10.5   5.8 |  13.7  56.7  330   8  4   9.6   5.3
  6750  14.1  57.4  360   8  4   9.8   5.4 |  14.4  57.9  330   8  4   9.4   5.2
  6500  14.8  58.6  360   7  4  10.0   5.5 |  15.1  59.2  330   7  4  10.2   5.6
  6250  15.6  60.1  360   7  4  11.1   6.1 |  15.9  60.6  325   7  4  11.1   6.1
  6000  16.4  61.5  360   7  4   9.4   5.2 |  16.7  62.1  325   7  4  10.3   5.7
  5750  17.2  63.0  360   7  4  13.1   7.2 |  17.5  63.5  325   7  4  10.6   5.8
  5500  18.5  65.3  360   7  3  24.0  13.2 |  18.3  64.9  325   7  3  13.0   7.2
________________________________________________________________________________

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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