Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 281345
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0745 MDT Thursday, May 28, 2015

This forecast is for Thursday, May 28, 2015:

If the trigger temperature of 67.9 F/19.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 963 ft/min (4.9 m/s)
   Maximum height of thermals.................. 15848 ft MSL (10563 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1230 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9717 ft MSL (4431 ft AGL)
Thermal soaring outlook for Friday 05/29....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 17592 ft MSL (12307 ft AGL)
Wave soaring outlook for Friday 05/29.......... Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 05:35:38 / 20:17:41 MDT
Total possible sunshine........... 14 hr 42 min 3 sec (882 min 3 sec)
Altitude of sun at 12:56:51 MDT... 71.71 degrees

Upper air data from rawinsonde observation taken on 05/28/2015 at 0600 MDT

Freezing level.................. 12824 ft MSL (7539 ft AGL)
Convective condensation level... 12583 ft MSL (7298 ft AGL)
Lifted condensation level....... 12964 ft MSL (7679 ft AGL)
Lifted index.................... -4.2
K index......................... +24.8

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  -59.0 -74.2   280   25   13   5.4   3.0  100.2 212.4    44.1      M    M
 45000  -61.5 -78.7   230   28   15  -1.3  -0.7   70.4 158.6    29.0      M    M
 40000  -60.3 -76.5   190   59   30 -16.7  -9.1   49.3 120.7    17.1      M    M
 38000  -59.4 -74.9   185   41   21   0.3   0.2   41.8 107.3    12.6      M    M
 36000  -55.3 -67.5   190   26   14   8.3   4.5   39.3 102.8    11.2      M    M
 34000  -50.1 -58.2   215   29   15   9.1   5.0   38.2 100.8    10.7      M    M
 32000  -44.6 -48.3   210   28   15   9.2   5.0   37.8 100.0    10.6      M    M
 30000  -38.3 -36.9   215   27   14   9.2   5.1   37.5  99.5    10.7      M    M
 29000  -35.6 -32.1   220   27   14   8.1   4.4   37.3  99.2    10.7      M    M
 28000  -33.6 -28.5   225   27   14   6.7   3.7   36.1  97.0     9.8      M    M
 27000  -31.6 -24.9   225   27   14   7.3   4.0   35.0  94.9     9.1      M    M
 26000  -30.1 -22.2   230   28   14  10.1   5.6   33.2  91.8     7.8      M    M
 25000  -27.5 -17.5   235   28   14   7.4   4.1   32.7  90.9     7.5      M    M
 24000  -25.5 -13.9   230   27   14   6.9   3.8   31.6  88.9     6.7      M    M
 23000  -23.2  -9.8   240   25   13  10.0   5.5   30.8  87.4     6.1      M    M
 22000  -21.3  -6.3   250   24   12   9.1   5.0   29.6  85.4     5.2      M    M
 21000  -19.0  -2.2   255   25   13   0.7   0.4   28.9  84.0     4.6      M    M
 20000  -17.5   0.5   260   27   14   8.9   4.9   27.3  81.1     3.2      M    M
 19500  -16.1   3.0   260   27   14   9.3   5.1   27.2  80.9     3.1      M    M
 19000  -14.7   5.5   260   27   14   9.4   5.1   27.1  80.8     3.1      M    M
 18500  -13.6   7.5   260   28   14   1.1   0.6   26.8  80.2     2.8      M    M
 18000  -13.0   8.6   260   28   15   9.7   5.3   25.7  78.2     1.9      M    M
 17500  -11.7  10.9   265   29   15   9.0   4.9   25.5  77.9     1.8      M    M
 17000  -10.4  13.3   265   30   15   8.6   4.7   25.4  77.7     1.6      M    M
 16500   -9.6  14.7   265   29   15   6.6   3.6   24.7  76.5     1.0      M    M
 16000   -8.7  16.3   265   27   14   4.6   2.5   24.2  75.6     0.4      M    M
 15500   -7.8  18.0   265   25   13   8.2   4.5   23.6  74.5    -0.2    943  4.8
 15000   -5.8  21.6   260   22   11   9.3   5.1   23.5  74.3    -0.3    859  4.4
 14500   -4.4  24.1   260   20   10   9.3   5.1   23.5  74.2    -0.4    802  4.1
 14000   -3.0  26.6   255   18    9   9.3   5.1   23.4  74.1    -0.4    746  3.8
 13500   -1.6  29.1   250   17    9   9.3   5.1   23.3  74.0    -0.6    690  3.5
 13000   -0.3  31.5   250   16    8   9.3   5.1   23.2  73.8    -0.7    634  3.2
 12500    1.1  34.0   245   16    8   9.3   5.1   23.2  73.7    -0.7    578  2.9
 12000    2.5  36.5   240   15    8   9.3   5.1   23.1  73.6    -0.8    522  2.7
 11500    3.9  39.0   235   12    6   8.8   4.8   23.0  73.4    -0.9    466  2.4
 11000    5.0  41.0   230   10    5   6.9   3.8   22.6  72.7    -1.3    419  2.1
 10500    5.9  42.6   225    8    4   7.3   4.0   22.2  72.0    -1.8    374  1.9
 10250    6.4  43.5   220    7    3   5.1   2.8   22.0  71.6    -2.0    353  1.8
 10000    6.7  44.1   220    3    2   2.3   1.3   21.5  70.6    -2.5    337  1.7
  9750    6.9  44.4   240    3    2   5.2   2.9   20.9  69.7    -3.0    322  1.6
  9500    7.5  45.5   255    4    2   8.4   4.6   20.8  69.4    -3.2    298  1.5
  9250    8.1  46.6   265    4    2   8.5   4.7   20.7  69.2    -3.3    272  1.4
  9000    8.8  47.8   275    5    3   8.7   4.8   20.6  69.0    -3.4    245  1.2
  8750    9.4  48.9   295    6    3   7.9   4.3   20.5  68.9    -3.5    219  1.1
  8500    9.9  49.8   310    7    4   6.7   3.7   20.3  68.5    -3.7    197  1.0
  8250   10.3  50.5   320    8    4   6.5   3.6   20.0  68.1    -4.1    177  0.9
  8000   10.7  51.3   325   10    5   6.8   3.7   19.8  67.6    -4.4    157  0.8
  7750   11.2  52.2   330   11    6   6.2   3.4   19.6  67.2    -4.7    136  0.7
  7500   11.6  52.9   335   13    7   8.9   4.9   19.3  66.8    -5.0    116  0.6
  7250   12.0  53.6   340   14    7  -0.6  -0.3   19.1  66.4    -5.3     96  0.5
  7000   11.1  52.0   345   16    8 -20.8 -11.4   17.5  63.4    -7.0    117  0.6
  6750    9.7  49.5   340   13    7  -2.5  -1.4   15.4  59.8    -9.1    151  0.8
  6500   10.3  50.5   325   11    6  13.6   7.5   15.5  60.0    -9.3    125  0.6
  6250   10.9  51.6   310    9    5   6.0   3.3   15.4  59.7    -9.5    101  0.5
  6000   11.4  52.5   285    8    4   7.5   4.1   15.2  59.4    -9.7     78  0.4
  5750   11.9  53.4   285    6    3   7.0   3.8   15.0  59.0    -9.9     55  0.3
  5500   12.4  54.3   280    5    2   7.4   4.1   14.8  58.7   -10.2     32  0.2

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

           05/28/2015 at 0900 MDT          |       05/28/2015 at 1200 MDT
                                           |
K index... +17.8  LI... +271.2             | K index... +24.8  LI... +270.5
CAPE... +111.0  CIN... -97.9               | CAPE... +348.6  CIN... -16.9
                                           |
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 -57.9 -72.2  235  14  7   0.9   0.5 | -58.7 -73.7  230  13  7   1.0   0.6
 45000 -57.1 -70.8  245  21 11  -2.6  -1.4 | -57.5 -71.5  225  16  8  -0.8  -0.4
 40000 -61.1 -78.0  205  36 19  -2.4  -1.3 | -58.7 -73.7  220  24 12  -0.6  -0.4
 38000 -58.7 -73.7  205  36 19   6.5   3.6 | -56.8 -70.2  220  25 13   4.6   2.5
 36000 -54.7 -66.5  200  33 17   6.5   3.6 | -54.0 -65.2  215  26 13   4.6   2.5
 34000 -49.7 -57.5  205  30 15   8.6   4.7 | -49.8 -57.6  215  26 14   8.3   4.5
 32000 -44.5 -48.1  205  28 14   8.6   4.7 | -44.8 -48.6  220  26 14   8.3   4.6
 30000 -39.3 -38.7  210  27 14   8.6   4.7 | -39.6 -39.3  225  28 14   8.9   4.9
 29000 -36.8 -34.2  210  26 14   8.6   4.7 | -36.9 -34.4  225  29 15   8.9   4.9
 28000 -34.2 -29.6  215  26 13   8.6   4.7 | -34.3 -29.7  230  30 15   8.9   4.9
 27000 -31.7 -25.1  215  26 13   8.1   4.5 | -31.7 -25.1  230  30 16   8.1   4.4
 26000 -29.3 -20.7  215  26 13   8.1   4.4 | -29.3 -20.7  230  31 16   8.0   4.4
 25000 -26.9 -16.4  215  25 13   8.1   4.5 | -26.9 -16.4  230  31 16   8.1   4.4
 24000 -24.6 -12.3  215  25 13   7.1   3.9 | -24.6 -12.3  230  31 16   7.3   4.0
 23000 -22.4  -8.3  215  25 13   7.2   3.9 | -22.3  -8.1  230  30 15   7.4   4.1
 22000 -20.3  -4.5  215  24 12   7.1   3.9 | -20.1  -4.2  230  29 15   7.4   4.0
 21000 -18.3  -0.9  220  22 12   6.2   3.4 | -18.1  -0.6  230  28 14   6.0   3.3
 20000 -16.4   2.5  225  20 10   6.2   3.4 | -16.3   2.7  230  26 13   6.0   3.3
 19500 -15.5   4.1  225  18  9   6.2   3.4 | -15.5   4.1  230  25 13   6.1   3.3
 19000 -14.6   5.7  230  17  9   6.2   3.4 | -14.6   5.7  230  24 12   6.1   3.3
 18500 -13.5   7.7  235  16  8   7.9   4.3 | -13.5   7.7  230  23 12   8.7   4.7
 18000 -12.4   9.7  240  15  8   7.7   4.2 | -11.7  10.9  235  21 11   8.5   4.7
 17500 -10.5  13.1  245  14  7   8.8   4.8 | -10.5  13.1  240  21 11   7.5   4.1
 17000  -9.2  15.4  250  15  8   8.8   4.8 |  -9.4  15.1  245  21 11   7.6   4.2
 16500  -8.0  17.6  250  15  8   7.6   4.2 |  -8.2  17.2  250  21 11   7.7   4.2
 16000  -6.9  19.6  255  16  8   7.4   4.0 |  -7.1  19.2  255  20 10   7.8   4.3
 15500  -5.9  21.4  255  17  9   7.6   4.1 |  -5.9  21.4  260  20 10   8.0   4.4
 15000  -4.7  23.5  255  17  9   7.8   4.3 |  -4.7  23.5  265  20 10   8.2   4.5
 14500  -3.6  25.5  260  17  9   7.9   4.3 |  -3.6  25.5  270  20 10   8.1   4.5
 14000  -2.5  27.5  260  17  9   8.0   4.4 |  -2.5  27.5  275  19 10   7.2   4.0
 13500  -1.3  29.7  260  16  8   7.9   4.4 |  -1.4  29.5  275  18  9   7.3   4.0
 13000  -0.0  32.0  260  15  8   9.4   5.2 |  -0.3  31.5  275  17  9   7.5   4.1
 12500   1.4  34.5  260  14  7   9.3   5.1 |   0.7  33.3  275  14  7   7.4   4.1
 12000   2.7  36.9  265  14  7   8.6   4.7 |   1.9  35.4  275  13  7   8.3   4.5
 11500   4.0  39.2  270  15  8   8.8   4.8 |   3.1  37.6  270  11  6   8.2   4.5
 11000   5.2  41.4  275  16  8   7.7   4.2 |   4.3  39.7  270  10  5   8.5   4.6
 10500   6.3  43.3  275  18  9   8.4   4.6 |   5.6  42.1  275   8  4   9.2   5.1
 10250   6.9  44.4  280  18  9   5.0   2.7 |   6.2  43.2  275   7  4   5.3   2.9
 10000   7.1  44.8  280  19 10   5.9   3.2 |   6.4  43.5  280   6  3   5.9   3.2
  9750   7.8  46.0  280  19 10   9.8   5.4 |   7.1  44.8  290   4  2  10.2   5.6
  9500   8.4  47.1  280  18  9   9.3   5.1 |   7.8  46.0  310   3  2   9.3   5.1
  9250   9.1  48.4  285  18  9   7.5   4.1 |   8.4  47.1  345   3  1   8.7   4.8
  9000   9.5  49.1  285  17  9   6.3   3.4 |   9.0  48.2  350   3  1   9.3   5.1
  8750  10.1  50.2  290  15  8   7.6   4.2 |   9.8  49.6  350   3  2  10.7   5.9
  8500  10.6  51.1  295  14  7   7.3   4.0 |  10.6  51.1  355   3  2  10.3   5.7
  8250  11.1  52.0  295  12  6   8.2   4.5 |  11.3  52.3  355   3  2  10.1   5.6
  8000  11.8  53.2  300  11  6   8.2   4.5 |  12.1  53.8  360   3  2   9.9   5.4
  7750  12.3  54.1  305  10  5   7.3   4.0 |  12.8  55.0  360   3  2   9.9   5.4
  7500  12.8  55.0  310   9  4   7.0   3.8 |  13.6  56.5  360   4  2  10.0   5.5
  7250  13.3  55.9  315   8  4   6.8   3.7 |  14.3  57.7  360   4  2  10.2   5.6
  7000  13.8  56.8  320   7  3   6.8   3.7 |  15.1  59.2  360   4  2  10.2   5.6
  6750  14.3  57.7  325   6  3   6.0   3.3 |  15.8  60.4  355   4  2   9.1   5.0
  6500  14.7  58.5  330   5  3   6.2   3.4 |  16.5  61.7  355   4  2   9.9   5.4
  6250  15.1  59.2  335   4  2   7.3   4.0 |  17.3  63.1  355   4  2  11.5   6.3
  6000  15.6  60.1  340   4  2   6.4   3.5 |  18.1  64.6  355   4  2  10.2   5.6
  5750  16.0  60.8  345   3  1   9.1   5.0 |  18.9  66.0  360   4  2  13.2   7.2
  5500  17.0  62.6  355   2  1  17.5   9.6 |  20.3  68.5  360   4  2  23.7  13.0

           05/28/2015 at 1500 MDT          |       05/28/2015 at 1800 MDT
                                           |
K index... +27.8  LI... +272.0             | K index... +15.7  LI... +271.8
CAPE... +175.1  CIN... -0.5                | CAPE... +181.2  CIN... -107.2
                                           |
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 -58.1 -72.6  235  13  7   1.0   0.6 | -57.9 -72.2  245  14  7   0.9   0.5
 45000 -56.8 -70.2  220  18  9  -0.7  -0.4 | -57.0 -70.6  235  19 10  -1.1  -0.6
 40000 -58.0 -72.4  225  21 11  -1.1  -0.6 | -58.9 -74.0  225  22 11  -1.7  -0.9
 38000 -56.1 -69.0  230  23 12   4.0   2.2 | -56.5 -69.7  215  24 13   5.0   2.7
 36000 -53.7 -64.7  240  25 13   4.0   2.2 | -53.5 -64.3  210  28 14   5.0   2.7
 34000 -49.9 -57.8  245  27 14   9.0   4.9 | -49.4 -56.9  205  30 15   8.8   4.8
 32000 -44.6 -48.3  245  27 14   9.0   4.9 | -44.2 -47.6  210  31 16   8.8   4.8
 30000 -39.2 -38.6  245  27 14   8.8   4.8 | -39.0 -38.2  215  30 16   8.3   4.6
 29000 -36.6 -33.9  245  27 14   8.8   4.8 | -36.6 -33.9  220  30 15   8.3   4.6
 28000 -33.3 -27.9  240  27 14   8.8   4.8 | -33.4 -28.1  225  30 15   8.3   4.6
 27000 -30.8 -23.4  240  26 14   8.2   4.5 | -31.1 -24.0  230  29 15   7.5   4.1
 26000 -28.4 -19.1  240  26 13   8.2   4.5 | -28.9 -20.0  235  29 15   7.5   4.1
 25000 -26.0 -14.8  240  25 13   8.2   4.5 | -26.7 -16.1  240  29 15   7.5   4.1
 24000 -23.7 -10.7  240  24 12   7.3   4.0 | -24.4 -11.9  245  28 14   7.9   4.3
 23000 -21.5  -6.7  240  23 12   7.3   4.0 | -22.0  -7.6  250  27 14   7.9   4.3
 22000 -19.4  -2.9  240  22 11   7.3   4.0 | -19.6  -3.3  255  26 14   7.9   4.3
 21000 -17.3   0.9  240  21 11   7.0   3.8 | -17.4   0.7  260  26 13   7.0   3.8
 20000 -15.2   4.6  235  20 10   7.0   3.8 | -15.3   4.5  265  25 13   6.9   3.8
 19500 -14.2   6.4  235  20 10   7.0   3.8 | -14.3   6.3  265  25 13   6.9   3.8
 19000 -13.2   8.2  235  19 10   6.9   3.8 | -13.3   8.1  265  25 13   7.0   3.8
 18500 -12.3   9.9  235  19 10   6.1   3.3 | -12.2  10.0  270  25 13   7.1   3.9
 18000 -11.4  11.5  235  18  9   6.2   3.4 | -11.1  12.0  270  26 13   7.1   3.9
 17500 -10.5  13.1  235  18  9   6.2   3.4 | -10.1  13.8  270  26 13   7.4   4.0
 17000  -9.6  14.7  230  17  9   6.2   3.4 |  -9.0  15.8  270  26 13   7.5   4.1
 16500  -8.7  16.3  230  17  9   6.2   3.4 |  -7.9  17.8  275  26 13   7.6   4.1
 16000  -7.8  18.0  225  17  9   6.4   3.5 |  -6.8  19.8  275  26 13   7.6   4.2
 15500  -6.8  19.8  225  17  9   6.4   3.5 |  -5.7  21.7  280  25 13   7.7   4.2
 15000  -5.5  22.1  225  15  8   6.3   3.4 |  -4.1  24.6  285  24 12   7.5   4.1
 14500  -4.6  23.7  230  14  7   6.3   3.4 |  -3.0  26.6  290  23 12   7.7   4.2
 14000  -3.6  25.5  235  12  6   6.3   3.5 |  -1.9  28.6  290  23 12   8.3   4.6
 13500  -2.7  27.1  240   9  5   6.3   3.5 |  -0.7  30.7  295  23 12   8.3   4.5
 13000  -1.7  28.9  255   7  4   7.8   4.3 |   0.5  32.9  300  22 11   8.5   4.6
 12500  -0.7  30.7  285   6  3   7.5   4.1 |   1.8  35.2  305  22 11   8.4   4.6
 12000   0.6  33.1  305   7  3   9.7   5.3 |   3.0  37.4  310  21 11   9.2   5.1
 11500   2.0  35.6  315   8  4   9.4   5.2 |   4.4  39.9  310  20 10   9.3   5.1
 11000   3.4  38.1  320   8  4   9.7   5.3 |   5.6  42.1  315  18  9   7.9   4.3
 10500   4.8  40.6  320   9  5  10.3   5.6 |   6.7  44.1  315  16  8   8.7   4.8
 10250   5.5  41.9  320   9  5   7.1   3.9 |   7.3  45.1  315  16  8   4.9   2.7
 10000   6.0  42.8  320   9  5   8.3   4.6 |   7.5  45.5  315  15  8   5.0   2.8
  9750   6.8  44.2  320  10  5  12.2   6.7 |   8.1  46.6  310  13  7   8.8   4.8
  9500   7.7  45.9  320  10  5  11.5   6.3 |   8.7  47.7  310  12  6   8.2   4.5
  9250   8.5  47.3  320  10  5   9.5   5.2 |   9.2  48.6  310  11  6   6.7   3.7
  9000   9.1  48.4  320  10  5   9.0   4.9 |   9.7  49.5  305  10  5   6.0   3.3
  8750   9.9  49.8  320  10  5  10.7   5.9 |  10.2  50.4  300   8  4   7.3   4.0
  8500  10.6  51.1  320  11  6  10.2   5.6 |  10.7  51.3  290   7  4   7.0   3.8
  8250  11.4  52.5  320  11  6  11.0   6.0 |  11.2  52.2  280   7  3   6.2   3.4
  8000  12.2  54.0  320  11  6  10.5   5.8 |  11.6  52.9  270   6  3   5.7   3.1
  7750  13.0  55.4  320  11  6   9.2   5.0 |  12.0  53.6  255   6  3   6.1   3.4
  7500  13.6  56.5  320  12  6   9.4   5.2 |  12.5  54.5  245   6  3   5.8   3.2
  7250  14.4  57.9  320  12  6  10.1   5.5 |  12.8  55.0  230   6  3   4.9   2.7
  7000  15.1  59.2  320  12  6  10.2   5.6 |  13.2  55.8  220   6  3   4.9   2.7
  6750  15.9  60.6  320  12  6  10.1   5.5 |  13.5  56.3  210   7  4   3.3   1.8
  6500  16.6  61.9  320  12  6  10.6   5.8 |  13.7  56.7  200   7  4   6.6   3.6
  6250  17.5  63.5  320  12  6  11.3   6.2 |  14.3  57.7  195   7  4  10.7   5.9
  6000  18.3  64.9  320  12  6  10.4   5.7 |  15.0  59.0  190   7  3   9.2   5.1
  5750  19.1  66.4  320  12  6  12.3   6.8 |  15.6  60.1  180   7  3  11.0   6.0
  5500  20.2  68.4  320  12  6  20.5  11.3 |  16.6  61.9  180   6  3  15.6   8.6
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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