Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271259
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0659 MDT Wednesday, May 27, 2015

This forecast is for Wednesday, May 27, 2015:

If the trigger temperature of 68.4 F/20.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1049 ft/min (5.3 m/s)
   Maximum height of thermals.................. 16595 ft MSL (11310 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11428 ft MSL (6142 ft AGL)
Thermal soaring outlook for Thursday 05/28..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16838 ft MSL (11553 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17329 ft MSL (12044 ft AGL)
Wave soaring outlook for Thursday 05/28........ Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 05:36:12 / 20:16:53 MDT
Total possible sunshine........... 14 hr 40 min 41 sec (880 min 41 sec)
Altitude of sun at 12:56:44 MDT... 71.55 degrees

Upper air data from rawinsonde observation taken on 05/27/2015 at 0600 MDT

Freezing level.................. 12286 ft MSL (7001 ft AGL)
Convective condensation level... 13586 ft MSL (8301 ft AGL)
Lifted condensation level....... 14602 ft MSL (9316 ft AGL)
Lifted index.................... -1.3
K index......................... +20.5

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -60.0 -76.0   265   21   11  -0.7  -0.4   98.4 209.2    42.8      M    M
 45000  -56.9 -70.4   270   32   17  -0.6  -0.3   79.2 174.5    33.9      M    M
 40000  -63.9 -83.0   270   31   16  -2.0  -1.1   44.0 111.2    13.3      M    M
 38000  -60.6 -77.1   260   27   14   8.1   4.4   40.3 104.5    11.1      M    M
 36000  -56.1 -69.0   235   25   13   7.2   3.9   38.2 100.8    10.0      M    M
 34000  -50.7 -59.3   225   24   13   9.5   5.2   37.6  99.6     9.8      M    M
 32000  -45.4 -49.7   220   23   12   7.2   3.9   36.9  98.4     9.5      M    M
 30000  -40.6 -41.1   215   21   11   9.2   5.1   35.5  95.8     8.7      M    M
 29000  -37.4 -35.3   220   21   11   6.8   3.7   34.9  94.7     8.4      M    M
 28000  -35.1 -31.2   230   20   10   7.9   4.3   34.0  93.3     7.9      M    M
 27000  -32.3 -26.1   235   20   10   9.7   5.3   33.8  92.9     7.8      M    M
 26000  -29.4 -20.9   240   21   11   9.7   5.3   33.8  92.9     7.9      M    M
 25000  -27.0 -16.6   245   21   11   6.8   3.8   33.2  91.7     7.4      M    M
 24000  -24.7 -12.5   245   20   10   7.1   3.9   32.4  90.4     7.0      M    M
 23000  -22.6  -8.7   245   18   10   7.2   3.9   31.5  88.6     6.2      M    M
 22000  -20.9  -5.6   245   17    9   4.8   2.6   30.1  86.2     5.1      M    M
 21000  -18.5  -1.3   240   15    8   8.6   4.7   29.4  84.9     4.5      M    M
 20000  -16.2   2.8   240   13    7   6.7   3.6   28.8  83.8     4.0      M    M
 19500  -15.2   4.6   235   15    8   7.0   3.8   28.2  82.8     3.6      M    M
 19000  -14.2   6.4   225   17    9   9.0   5.0   27.7  81.9     3.1      M    M
 18500  -13.3   8.1   230   17    9   3.3   1.8   27.1  80.8     2.6      M    M
 18000  -12.4   9.7   245   17    9   6.7   3.7   26.5  79.7     2.0      M    M
 17500  -11.4  11.5   255   17    9   6.8   3.8   26.0  78.8     1.6      M    M
 17000  -10.4  13.3   265   18    9   6.6   3.6   25.5  77.9     1.1      M    M
 16500  -10.1  13.8   275   19   10   2.6   1.4   24.3  75.8    -0.0   1049  5.3
 16000   -9.0  15.8   285   21   11   9.3   5.1   24.0  75.2    -0.3   1000  5.1
 15500   -7.6  18.3   285   21   11   8.9   4.9   23.9  75.0    -0.4    944  4.8
 15000   -6.4  20.5   285   21   11   7.8   4.3   23.6  74.5    -0.7    893  4.5
 14500   -4.6  23.7   280   20   10   7.6   4.2   23.1  73.7    -1.1    819  4.2
 14000   -3.8  25.2   280   19   10   5.2   2.9   22.5  72.6    -1.7    778  4.0
 13500   -3.0  26.6   280   17    9   7.5   4.1   21.9  71.4    -2.4    740  3.8
 13000   -1.7  28.9   280   14    7   8.9   4.9   21.7  71.1    -2.6    686  3.5
 12500   -0.3  31.5   275   11    6   9.0   4.9   21.6  70.9    -2.7    631  3.2
 12000    1.0  33.8   275    9    5   9.0   4.9   21.5  70.7    -2.8    576  2.9
 11500    2.3  36.1   275   10    5   9.0   4.9   21.4  70.5    -3.0    521  2.6
 11000    3.7  38.7   280   10    5   9.0   4.9   21.2  70.2    -3.2    466  2.4
 10500    5.0  41.0   280   11    6   9.0   4.9   21.1  70.0    -3.3    412  2.1
 10250    5.7  42.3   280   11    6   9.2   5.1   21.1  69.9    -3.3    384  2.0
 10000    6.4  43.5   285   10    5   9.4   5.2   21.0  69.9    -3.4    356  1.8
  9750    7.1  44.8   285   10    5   9.4   5.1   21.0  69.8    -3.4    327  1.7
  9500    7.8  46.0   290    9    5   9.4   5.1   21.0  69.8    -3.5    299  1.5
  9250    8.5  47.3   295    8    4   9.4   5.2   21.0  69.7    -3.5    271  1.4
  9000    9.2  48.6   300    8    4   9.3   5.1   20.9  69.7    -3.5    242  1.2
  8750    9.9  49.8   300    8    4   9.7   5.3   20.9  69.6    -3.6    214  1.1
  8500   10.6  51.1   300    7    4   8.1   4.4   20.9  69.6    -3.6    186  0.9
  8250   11.0  51.8   300    7    4   5.2   2.8   20.6  69.1    -3.9    165  0.8
  8000   11.3  52.3   300    7    4   4.8   2.6   20.2  68.4    -4.4    150  0.8
  7750   11.6  52.9   285    7    4   4.8   2.6   19.8  67.7    -4.8    134  0.7
  7500   11.9  53.4   275    7    4   6.0   3.3   19.5  67.1    -5.3    117  0.6
  7250   12.3  54.1   265    8    4   4.5   2.5   19.2  66.6    -5.6     96  0.5
  7000   12.4  54.3   255    9    5  -3.2  -1.8   18.5  65.3    -6.2     86  0.4
  6750   12.0  53.6   255    9    5  -7.1  -3.9   17.3  63.2    -7.4     92  0.5
  6500   11.7  53.1   255    9    4   1.2   0.6   16.3  61.3    -8.5     94  0.5
  6250   12.0  53.6   250    8    4   6.4   3.5   15.9  60.7    -8.9     76  0.4
  6000   12.4  54.3   250    8    4   5.9   3.2   15.6  60.1    -9.3     58  0.3
  5750   12.7  54.9   240    7    3   3.0   1.7   15.3  59.5    -9.7     40  0.2
  5500   12.3  54.1   220    5    3 -18.3 -10.0   14.1  57.5   -10.9     46  0.2

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

           05/27/2015 at 0900 MDT          |       05/27/2015 at 1200 MDT
                                           |
K index... +24.0  LI... +273.4             | K index... +24.8  LI... +271.4
CAPE... +5.6  CIN... -17.8                 | CAPE... +264.6  CIN... -21.5
                                           |
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 -58.4 -73.1  270  17  9  -0.2  -0.1 | -58.7 -73.7  265  16  8   0.2   0.1
 45000 -58.8 -73.8  270  22 11  -0.7  -0.4 | -58.5 -73.3  260  26 13  -0.3  -0.2
 40000 -59.9 -75.8  255  31 16  -0.6  -0.3 | -59.0 -74.2  260  35 18  -0.2  -0.1
 38000 -57.6 -71.7  250  30 15   5.3   2.9 | -57.0 -70.6  265  34 18   4.5   2.5
 36000 -54.4 -65.9  245  28 14   5.3   2.9 | -54.3 -65.7  265  31 16   4.5   2.5
 34000 -50.6 -59.1  245  25 13   8.0   4.4 | -50.7 -59.3  265  28 14   8.1   4.4
 32000 -45.8 -50.4  240  21 11   8.0   4.4 | -45.3 -49.5  265  23 12   8.0   4.4
 30000 -40.2 -40.4  240  18  9   8.5   4.7 | -40.1 -40.2  260  20 10   9.0   4.9
 29000 -37.7 -35.9  235  18  9   8.5   4.7 | -37.5 -35.5  260  19 10   9.0   4.9
 28000 -35.1 -31.2  230  17  9   8.5   4.7 | -34.8 -30.6  255  18  9   9.0   4.9
 27000 -32.6 -26.7  230  17  9   8.6   4.7 | -32.2 -26.0  255  17  9   8.1   4.5
 26000 -30.0 -22.0  235  17  9   8.6   4.7 | -29.8 -21.6  250  17  9   8.1   4.4
 25000 -27.4 -17.3  235  17  9   8.6   4.7 | -27.4 -17.3  245  17  9   8.1   4.4
 24000 -25.0 -13.0  235  17  9   7.6   4.2 | -25.0 -13.0  245  17  9   7.5   4.1
 23000 -22.7  -8.9  240  16  8   7.7   4.2 | -22.8  -9.0  240  17  9   7.6   4.2
 22000 -20.4  -4.7  240  16  8   7.7   4.2 | -20.5  -4.9  240  18  9   7.6   4.2
 21000 -18.2  -0.8  245  16  8   7.4   4.1 | -18.4  -1.1  235  18  9   7.2   3.9
 20000 -16.0   3.2  245  16  8   7.5   4.1 | -16.3   2.7  230  18  9   7.2   3.9
 19500 -14.9   5.2  250  16  8   7.5   4.1 | -15.2   4.6  230  17  9   7.2   3.9
 19000 -13.8   7.2  250  16  8   7.5   4.1 | -14.1   6.6  225  17  9   7.2   3.9
 18500 -12.8   9.0  250  16  8   7.2   3.9 | -13.1   8.4  225  17  9   6.9   3.8
 18000 -11.7  10.9  255  16  8   7.2   4.0 | -12.1  10.2  225  17  9   6.9   3.8
 17500 -10.7  12.7  255  15  8   7.3   4.0 | -11.1  12.0  225  17  9   7.3   4.0
 17000  -9.6  14.7  255  15  8   7.3   4.0 |  -9.4  15.1  225  16  8   7.5   4.1
 16500  -8.5  16.7  255  14  7   7.1   3.9 |  -8.4  16.9  225  16  8   6.9   3.8
 16000  -7.1  19.2  255  13  7   6.2   3.4 |  -7.4  18.7  230  15  8   6.8   3.7
 15500  -6.2  20.8  255  12  6   5.9   3.3 |  -6.4  20.5  230  15  7   6.4   3.5
 15000  -5.4  22.3  255  11  6   5.7   3.1 |  -5.5  22.1  235  14  7   6.0   3.3
 14500  -4.6  23.7  250  10  5   5.9   3.3 |  -4.7  23.5  235  13  7   6.4   3.5
 14000  -3.6  25.5  250   9  5   7.4   4.1 |  -3.6  25.5  235  12  6   8.0   4.4
 13500  -2.5  27.5  250   7  4   7.3   4.0 |  -2.4  27.7  240  11  6   8.0   4.4
 13000  -1.3  29.7  255   6  3   8.8   4.8 |  -1.1  30.0  245  10  5   9.3   5.1
 12500  -0.0  32.0  260   6  3   8.7   4.8 |   0.2  32.4  250  10  5   9.2   5.0
 12000   1.3  34.3  275   6  3   8.7   4.8 |   1.6  34.9  265  10  5   8.9   4.9
 11500   2.5  36.5  285   8  4   8.7   4.8 |   2.9  37.2  275  11  6   9.1   5.0
 11000   3.8  38.8  290   9  5   8.9   4.9 |   4.1  39.4  285  11  6   7.4   4.1
 10500   5.2  41.4  290  11  6   9.9   5.4 |   5.2  41.4  300  11  5   7.9   4.4
 10250   5.8  42.4  290  12  6   5.1   2.8 |   5.7  42.3  305  11  5   4.3   2.3
 10000   6.0  42.8  290  13  6   5.3   2.9 |   5.9  42.6  305  10  5   5.7   3.1
  9750   6.7  44.1  290  14  7  10.0   5.5 |   6.6  43.9  305   8  4   9.9   5.4
  9500   7.4  45.3  290  15  8   9.0   5.0 |   7.2  45.0  310   7  4   8.9   4.9
  9250   8.0  46.4  290  16  8   6.4   3.5 |   7.8  46.0  310   6  3   7.4   4.1
  9000   8.3  46.9  290  16  8   5.2   2.8 |   8.3  46.9  310   4  2   7.7   4.2
  8750   8.8  47.8  290  15  8   6.9   3.8 |   8.9  48.0  315   3  2   9.4   5.2
  8500   9.3  48.7  290  15  8   6.5   3.6 |   9.6  49.3  315   2  1   9.1   5.0
  8250   9.7  49.5  290  14  7   6.8   3.7 |  10.2  50.4  320   2  1   9.9   5.4
  8000  10.2  50.4  290  12  6   6.8   3.7 |  11.0  51.8  325   1  1   9.9   5.4
  7750  10.7  51.3  290  11  5   6.7   3.7 |  11.7  53.1  325   1  1   9.1   5.0
  7500  11.2  52.2  290   9  5   6.7   3.7 |  12.4  54.3  325   1  1   9.5   5.2
  7250  11.7  53.1  290   8  4   6.7   3.7 |  13.1  55.6  325   1  1  10.3   5.6
  7000  12.2  54.0  290   6  3   6.8   3.7 |  13.9  57.0  325   1  1  10.2   5.6
  6750  12.7  54.9  290   5  3   7.0   3.8 |  14.6  58.3  325   1  1  10.1   5.5
  6500  13.1  55.6  290   4  2   6.5   3.5 |  15.4  59.7  325   2  1  10.7   5.8
  6250  13.6  56.5  285   3  1   6.3   3.5 |  16.2  61.2  325   2  1  11.7   6.4
  6000  14.0  57.2  275   2  1   5.3   2.9 |  17.1  62.8  325   2  1  10.0   5.5
  5750  14.4  57.9  240   1  1   9.3   5.1 |  17.9  64.2  330   2  1  13.3   7.3
  5500  15.5  59.9  220   1  1  20.7  11.3 |  19.3  66.7  335   2  1  25.1  13.8

           05/27/2015 at 1500 MDT          |       05/27/2015 at 1800 MDT
                                           |
K index... +25.9  LI... +272.8             | K index... +21.7  LI... +271.8
CAPE... +22.8  CIN... -20.0                | CAPE... +148.4  CIN... -69.6
                                           |
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 -59.3 -74.7  250  15  8  -0.5  -0.3 | -59.4 -74.9  245  15  8  -0.2  -0.1
 45000 -60.1 -76.2  255  25 13  -0.5  -0.3 | -60.0 -76.0  255  24 12  -1.9  -1.0
 40000 -60.8 -77.4  260  38 20  -0.6  -0.3 | -62.9 -81.2  255  37 19  -2.4  -1.3
 38000 -58.1 -72.6  260  37 19   5.9   3.2 | -59.2 -74.6  255  38 19   8.2   4.5
 36000 -54.5 -66.1  260  34 18   5.9   3.2 | -54.2 -65.6  255  38 19   8.2   4.5
 34000 -49.4 -56.9  260  30 15   9.1   5.0 | -48.6 -55.5  250  33 17   8.5   4.7
 32000 -44.0 -47.2  260  25 13   9.1   5.0 | -43.5 -46.3  235  25 13   8.5   4.7
 30000 -38.6 -37.5  255  22 11   8.8   4.8 | -38.3 -36.9  235  23 12   8.6   4.7
 29000 -36.0 -32.8  255  21 11   8.8   4.9 | -35.7 -32.3  240  23 12   8.6   4.7
 28000 -33.3 -27.9  250  20 10   8.9   4.9 | -33.2 -27.8  245  23 12   8.7   4.8
 27000 -30.9 -23.6  250  20 10   8.0   4.4 | -30.7 -23.3  250  24 12   8.0   4.4
 26000 -28.5 -19.3  250  20 10   7.9   4.4 | -28.3 -18.9  255  24 12   8.0   4.4
 25000 -26.1 -15.0  250  20 10   7.9   4.4 | -25.9 -14.6  260  25 13   8.0   4.4
 24000 -23.8 -10.8  250  20 10   7.3   4.0 | -23.6 -10.5  260  25 13   7.4   4.0
 23000 -21.7  -7.1  255  20 10   7.4   4.1 | -21.4  -6.5  260  25 13   7.4   4.1
 22000 -19.5  -3.1  255  20 10   7.4   4.1 | -19.2  -2.6  265  24 13   7.4   4.1
 21000 -17.3   0.9  260  20 11   7.1   3.9 | -17.1   1.2  265  24 12   7.0   3.9
 20000 -15.2   4.6  265  21 11   7.1   3.9 | -15.0   5.0  265  24 12   7.0   3.9
 19500 -14.2   6.4  265  21 11   7.1   3.9 | -14.0   6.8  270  24 12   7.0   3.9
 19000 -13.2   8.2  265  21 11   7.1   3.9 | -13.0   8.6  270  23 12   7.1   3.9
 18500 -12.1  10.2  270  21 11   6.8   3.7 | -11.9  10.6  270  24 12   7.5   4.1
 18000 -11.1  12.0  270  22 11   6.9   3.8 | -10.8  12.6  270  24 12   7.5   4.1
 17500 -10.2  13.6  270  22 11   6.6   3.6 |  -9.1  15.6  270  24 12   8.0   4.4
 17000  -8.7  16.3  265  23 12   6.5   3.6 |  -7.9  17.8  275  24 12   7.9   4.3
 16500  -7.8  18.0  265  22 12   6.8   3.7 |  -6.7  19.9  275  23 12   8.6   4.7
 16000  -6.8  19.8  265  22 11   6.8   3.7 |  -5.4  22.3  275  22 11   8.6   4.7
 15500  -5.8  21.6  260  21 11   6.6   3.6 |  -4.1  24.6  275  21 11   8.0   4.4
 15000  -4.9  23.2  260  21 11   6.3   3.5 |  -3.0  26.6  275  19 10   7.5   4.1
 14500  -4.0  24.8  255  20 10   6.3   3.5 |  -1.9  28.6  275  18  9   7.4   4.1
 14000  -3.0  26.6  255  19 10   6.7   3.7 |  -0.8  30.6  270  16  8   7.2   3.9
 13500  -2.0  28.4  250  18  9   6.7   3.6 |   0.2  32.4  270  15  8   7.2   3.9
 13000  -1.1  30.0  250  16  8   6.5   3.6 |   1.3  34.3  260  14  7   8.2   4.5
 12500  -0.1  31.8  250  14  7   6.3   3.5 |   2.5  36.5  255  13  7   8.1   4.5
 12000   0.9  33.6  245  12  6   8.4   4.6 |   3.7  38.7  245  14  7   7.9   4.4
 11500   2.2  36.0  245  10  5   8.0   4.4 |   4.9  40.8  230  14  7   8.0   4.4
 11000   3.4  38.1  245   8  4   9.5   5.2 |   6.0  42.8  220  15  8   7.4   4.0
 10500   4.8  40.6  245   8  4   9.7   5.3 |   7.1  44.8  210  15  8   8.1   4.4
 10250   5.5  41.9  245   7  4   6.0   3.3 |   7.6  45.7  205  15  8   4.8   2.6
 10000   5.9  42.6  245   7  4   8.0   4.4 |   7.9  46.2  205  15  8   5.9   3.2
  9750   6.7  44.1  245   7  4  12.6   6.9 |   8.5  47.3  200  14  7   9.9   5.4
  9500   7.6  45.7  245   7  3  11.5   6.3 |   9.2  48.6  200  14  7   9.2   5.0
  9250   8.4  47.1  250   6  3   8.9   4.9 |   9.8  49.6  195  14  7   7.6   4.2
  9000   9.0  48.2  250   6  3   8.6   4.7 |  10.3  50.5  195  14  7   7.6   4.2
  8750   9.8  49.6  250   6  3  10.8   5.9 |  11.0  51.8  190  13  7   9.4   5.2
  8500  10.5  50.9  250   6  3  10.2   5.6 |  11.6  52.9  190  13  7   9.0   4.9
  8250  11.3  52.3  250   6  3  10.6   5.8 |  12.3  54.1  185  12  6   9.6   5.2
  8000  12.1  53.8  255   6  3  10.4   5.7 |  13.0  55.4  185  12  6   9.4   5.2
  7750  12.8  55.0  255   6  3   9.8   5.4 |  13.7  56.7  185  11  6   8.8   4.8
  7500  13.5  56.3  255   6  3   9.8   5.4 |  14.3  57.7  180  11  6   8.8   4.9
  7250  14.3  57.7  260   6  3  10.0   5.5 |  15.0  59.0  180  10  5   9.1   5.0
  7000  15.0  59.0  260   6  3  10.0   5.5 |  15.6  60.1  180  10  5   9.2   5.0
  6750  15.7  60.3  260   6  3   9.8   5.4 |  16.3  61.3  185   9  5   9.4   5.1
  6500  16.5  61.7  260   6  3  10.4   5.7 |  17.0  62.6  185   9  5   9.7   5.3
  6250  17.3  63.1  260   6  3  11.3   6.2 |  17.7  63.9  185   8  4   9.9   5.5
  6000  18.1  64.6  265   6  3  10.2   5.6 |  18.5  65.3  185   8  4   9.7   5.3
  5750  18.9  66.0  265   6  3  12.3   6.8 |  19.2  66.6  185   8  4  10.2   5.6
  5500  20.0  68.0  265   5  3  20.1  11.0 |  20.0  68.0  190   7  4  12.3   6.7
________________________________________________________________________________

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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