Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230022
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1822 MDT Sunday, March 22, 2015

This forecast is for Monday, March 23, 2015:

If the trigger temperature of 57.8 F/14.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1103 ft/min (5.6 m/s)
   Maximum height of thermals.................. 17920 ft MSL (12613 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1045 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................. 13347 ft MSL (8041 ft AGL)
Thermal soaring outlook for Tuesday 03/24...... Good

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....................... 38999 ft MSL (33692 ft AGL)
Wave soaring outlook for Tuesday 03/24......... Poor

Remarks... None

Sunrise/Sunset.................... 06:58:20 / 19:13:20 MDT
Total possible sunshine........... 12 hr 14 min 59 sec (734 min 59 sec)
Altitude of sun at 13:06:01 MDT... 51.37 degrees

Upper air data from numerical model forecast valid on 03/23/2015 at 0600 MDT

Freezing level.................. 10561 ft MSL (5254 ft AGL)
Convective condensation level... 14316 ft MSL (9009 ft AGL)
Lifted condensation level....... 15449 ft MSL (10142 ft AGL)
Lifted index.................... -1.5
K index......................... +17.9

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -57.9 -72.2   265   36   18   1.8   1.0      M     M       M      M    M
 45000  -55.1 -67.2   265   45   23  -1.2  -0.7      M     M       M      M    M
 40000  -60.8 -77.4   270   70   36  -3.8  -2.1      M     M       M      M    M
 38000  -60.6 -77.1   270   74   38   4.7   2.6      M     M       M      M    M
 36000  -57.8 -72.0   270   72   37   4.7   2.6      M     M       M      M    M
 34000  -54.7 -66.5   265   69   35   7.7   4.2      M     M       M      M    M
 32000  -50.3 -58.5   265   62   32   7.4   4.1      M     M       M      M    M
 30000  -44.9 -48.8   265   53   27   9.5   5.2   30.3  86.5     6.5      M    M
 29000  -42.0 -43.6   265   49   25   9.5   5.2   30.1  86.2     6.4      M    M
 28000  -39.2 -38.6   265   45   23   9.5   5.2   30.1  86.1     6.5      M    M
 27000  -36.4 -33.5   265   41   21   8.1   4.5   30.0  86.0     6.5      M    M
 26000  -34.1 -29.4   265   42   21   7.9   4.3   29.2  84.5     5.9      M    M
 25000  -31.7 -25.1   265   43   22   7.9   4.3   28.5  83.2     5.4      M    M
 24000  -29.4 -20.9   265   43   22   7.1   3.9   27.9  82.2     5.0      M    M
 23000  -27.5 -17.5   265   42   22   6.4   3.5   26.6  79.8     3.9      M    M
 22000  -25.6 -14.1   260   41   21   6.4   3.5   25.4  77.7     3.0      M    M
 21000  -23.6 -10.5   255   39   20   7.5   4.1   24.3  75.8     2.1      M    M
 20000  -21.3  -6.3   255   36   18   7.6   4.2   23.5  74.3     1.4      M    M
 19500  -20.2  -4.4   260   34   17   7.6   4.2   23.1  73.6     1.1      M    M
 19000  -19.0  -2.2   260   32   16   7.6   4.2   22.8  73.0     0.8      M    M
 18500  -17.9  -0.2   260   30   15   7.3   4.0   22.4  72.4     0.5      M    M
 18000  -16.8   1.8   265   28   15   7.2   4.0   22.0  71.5     0.1      M    M
 17500  -15.7   3.7   270   27   14   7.5   4.1   21.5  70.7    -0.2   1073  5.5
 17000  -14.5   5.9   270   25   13   9.1   5.0   21.3  70.3    -0.5   1020  5.2
 16500  -13.2   8.2   265   24   12   9.2   5.1   21.2  70.1    -0.6    966  4.9
 16000  -11.5  11.3   265   22   11   6.7   3.7   20.6  69.1    -1.1    894  4.5
 15500  -10.6  12.9   265   21   11   6.9   3.8   20.1  68.3    -1.7    851  4.3
 15000   -9.4  15.1   260   20   10   8.6   4.7   19.8  67.7    -2.0    803  4.1
 14500   -8.2  17.2   255   18    9   8.5   4.7   19.6  67.3    -2.3    751  3.8
 14000   -7.0  19.4   250   17    9   7.4   4.1   19.3  66.8    -2.6    701  3.6
 13500   -5.9  21.4   240   16    8   7.4   4.1   18.9  66.0    -2.9    653  3.3
 13000   -4.9  23.2   235   15    8   6.6   3.6   18.5  65.3    -3.4    607  3.1
 12500   -4.0  24.8   220   13    7   6.5   3.5   18.0  64.3    -3.9    564  2.9
 12000   -3.0  26.6   210   13    7   7.2   4.0   17.5  63.5    -4.4    520  2.6
 11500   -1.9  28.6   205   12    6   7.5   4.1   17.1  62.8    -4.8    472  2.4
 11000   -0.8  30.6   200   11    6   6.7   3.7   16.7  62.1    -5.2    424  2.2
 10500    0.2  32.4   190   13    7   7.3   4.0   16.2  61.1    -5.7    382  1.9
 10250    0.6  33.1   190   13    7   3.4   1.8   15.9  60.7    -6.0    360  1.8
 10000    0.8  33.4   190   14    7   4.5   2.4   15.3  59.6    -6.6    348  1.8
  9750    1.4  34.5   185   15    8   9.1   5.0   15.2  59.3    -6.8    323  1.6
  9500    2.0  35.6   185   16    8   8.1   4.4   15.1  59.1    -6.9    298  1.5
  9250    2.6  36.7   185   17    9   7.5   4.1   14.9  58.9    -7.0    272  1.4
  9000    3.1  37.6   180   18    9   6.4   3.5   14.7  58.5    -7.3    250  1.3
  8750    3.6  38.5   180   20   10   6.8   3.7   14.5  58.0    -7.5    228  1.2
  8500    4.1  39.4   175   21   11   7.1   3.9   14.2  57.6    -7.8    205  1.0
  8250    4.6  40.3   175   23   12   5.8   3.2   14.0  57.2    -8.0    182  0.9
  8000    5.0  41.0   175   24   12   4.7   2.6   13.6  56.5    -8.4    163  0.8
  7750    5.4  41.7   175   25   13   5.2   2.8   13.3  55.9    -8.7    143  0.7
  7500    5.8  42.4   175   25   13   5.6   3.1   12.9  55.3    -9.0    124  0.6
  7250    6.3  43.3   175   24   13   6.5   3.5   12.6  54.7    -9.4    103  0.5
  7000    6.7  44.1   175   22   11   6.6   3.6   12.4  54.3    -9.7     82  0.4
  6750    7.2  45.0   175   19   10   6.9   3.8   12.2  53.9   -10.0     61  0.3
  6500    7.5  45.5   180   17    9   2.3   1.3   11.8  53.3   -10.4     43  0.2
  6250    7.4  45.3   180   13    7  -1.5  -0.8   11.1  51.9   -11.2     38  0.2
  6000    7.3  45.1   185   10    5  -0.0  -0.0   10.3  50.5   -12.1     34  0.2
  5750    7.3  45.1   195    7    4  -1.6  -0.9    9.5  49.1   -12.9     29  0.1
  5500    6.9  44.4   200    4    2  -5.8  -3.2    8.5  47.3   -14.0     32  0.2

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

           03/23/2015 at 0900 MDT          |       03/23/2015 at 1200 MDT
                                           |
K index... +19.4  LI... +272.9             | K index... +13.6  LI... +272.9
CAPE... +16.3  CIN... -36.8                | CAPE... +20.9  CIN... -93.4
                                           |
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 -58.2 -72.8  265  37 19   1.8   1.0 | -57.5 -71.5  265  35 18   1.5   0.8
 45000 -55.4 -67.7  265  49 25  -0.4  -0.2 | -55.0 -67.0  260  51 26   0.0   0.0
 40000 -59.1 -74.4  265  64 33  -2.5  -1.4 | -58.0 -72.4  255  60 31  -2.0  -1.1
 38000 -59.1 -74.4  260  67 35   2.7   1.5 | -58.2 -72.8  250  61 32   2.0   1.1
 36000 -57.5 -71.5  260  67 35   2.7   1.5 | -57.0 -70.6  245  62 32   2.0   1.1
 34000 -55.4 -67.7  260  66 34   9.0   4.9 | -55.4 -67.7  245  61 32   8.2   4.5
 32000 -50.4 -58.7  255  60 31   8.4   4.6 | -50.6 -59.1  240  56 29   7.9   4.3
 30000 -44.6 -48.3  255  51 26   9.2   5.1 | -45.1 -49.2  240  50 26   9.4   5.2
 29000 -41.8 -43.2  255  45 23   9.3   5.1 | -42.2 -44.0  240  46 24   9.5   5.2
 28000 -39.0 -38.2  255  39 20   9.3   5.1 | -39.4 -38.9  240  42 21   9.5   5.2
 27000 -36.3 -33.3  255  34 17   7.8   4.3 | -36.6 -33.9  240  38 19   8.3   4.6
 26000 -34.1 -29.4  250  36 19   7.4   4.1 | -34.3 -29.7  240  40 20   7.6   4.2
 25000 -31.9 -25.4  250  39 20   7.4   4.1 | -32.0 -25.6  245  42 21   7.6   4.2
 24000 -29.7 -21.5  250  41 21   6.9   3.8 | -29.8 -21.6  245  44 22   7.1   3.9
 23000 -27.8 -18.0  245  38 20   6.3   3.5 | -28.0 -18.4  240  39 20   5.7   3.1
 22000 -25.9 -14.6  240  35 18   6.3   3.5 | -26.3 -15.3  230  33 17   5.7   3.1
 21000 -23.9 -11.0  235  33 17   7.4   4.1 | -24.6 -12.3  225  29 15   7.0   3.8
 20000 -21.7  -7.1  235  30 16   7.6   4.1 | -22.3  -8.1  235  26 13   7.5   4.1
 19500 -20.6  -5.1  235  29 15   7.6   4.1 | -21.2  -6.2  240  25 13   7.5   4.1
 19000 -19.4  -2.9  235  28 14   7.6   4.1 | -20.0  -4.0  245  24 12   7.5   4.1
 18500 -18.3  -0.9  240  27 14   6.8   3.7 | -18.9  -2.0  250  23 12   7.5   4.1
 18000 -17.4   0.7  235  26 13   6.5   3.6 | -17.8  -0.0  250  24 12   7.4   4.1
 17500 -16.5   2.3  235  25 13   6.8   3.7 | -16.7   1.9  250  24 12   7.4   4.0
 17000 -15.2   4.6  240  24 12  10.0   5.5 | -15.5   4.1  250  24 13   9.4   5.2
 16500 -13.8   7.2  240  23 12   9.9   5.4 | -14.1   6.6  250  24 13   9.3   5.1
 16000 -11.8  10.8  245  21 11   8.4   4.6 | -12.2  10.0  250  24 12   7.9   4.3
 15500 -10.5  13.1  245  20 10   8.4   4.6 | -11.0  12.2  245  23 12   7.9   4.3
 15000  -9.3  15.3  245  19 10   8.9   4.9 |  -9.8  14.4  245  22 11   9.1   5.0
 14500  -8.0  17.6  250  19 10   8.9   4.9 |  -8.4  16.9  240  21 11   9.0   5.0
 14000  -6.7  19.9  250  18  9   8.5   4.6 |  -7.1  19.2  240  21 11   9.0   5.0
 13500  -5.4  22.3  250  17  9   8.5   4.6 |  -5.8  21.6  235  20 10   9.1   5.0
 13000  -4.2  24.4  250  17  9   8.4   4.6 |  -4.4  24.1  235  20 10   9.1   5.0
 12500  -3.0  26.6  245  16  8   8.4   4.6 |  -3.1  26.4  230  20 10   9.2   5.0
 12000  -1.7  28.9  245  15  8   8.1   4.4 |  -1.7  28.9  230  20 10   9.0   4.9
 11500  -0.6  30.9  245  14  7   7.9   4.4 |  -0.4  31.3  225  19 10   8.8   4.8
 11000   0.6  33.1  240  13  7   7.2   3.9 |   0.9  33.6  225  18  9   8.0   4.4
 10500   1.6  34.9  240  12  6   7.4   4.1 |   1.9  35.4  225  17  9   6.8   3.7
 10250   2.1  35.8  240  12  6   4.2   2.3 |   2.5  36.5  225  17  9   9.7   5.3
 10000   2.3  36.1  240  12  6   3.9   2.2 |   3.3  37.9  220  16  8   9.6   5.3
  9750   2.8  37.0  235  12  6   6.8   3.7 |   3.8  38.8  220  15  8   6.6   3.6
  9500   3.2  37.8  235  11  6   6.3   3.5 |   4.4  39.9  220  14  7   7.5   4.1
  9250   3.7  38.7  235  11  6   5.4   3.0 |   4.9  40.8  220  13  7   7.0   3.9
  9000   4.0  39.2  235  11  5   3.6   2.0 |   5.3  41.5  220  12  6   4.7   2.6
  8750   4.3  39.7  230  11  5   3.7   2.0 |   5.6  42.1  220  11  6   3.1   1.7
  8500   4.6  40.3  225  11  6   3.9   2.2 |   5.8  42.4  220  10  5   3.7   2.0
  8250   4.9  40.8  220  11  6   4.1   2.2 |   6.1  43.0  220   9  5   2.7   1.5
  8000   5.2  41.4  205  13  7   4.3   2.4 |   6.2  43.2  220   8  4   1.1   0.6
  7750   5.5  41.9  190  16  8   3.8   2.1 |   6.2  43.2  215   7  3   1.7   0.9
  7500   5.7  42.3  185  19 10   3.4   1.9 |   6.4  43.5  205   6  3   1.1   0.6
  7250   6.0  42.8  180  21 11   3.0   1.6 |   6.5  43.7  185   6  3   6.0   3.3
  7000   6.2  43.2  180  22 12   2.7   1.5 |   7.2  45.0  175   6  3  10.8   5.9
  6750   6.4  43.5  175  24 12   2.1   1.2 |   7.8  46.0  165   6  3   9.2   5.0
  6500   6.5  43.7  175  23 12  -0.1  -0.0 |   8.5  47.3  165   6  3   9.7   5.3
  6250   6.3  43.3  175  20 10  -1.1  -0.6 |   9.3  48.7  165   6  3  10.5   5.8
  6000   6.2  43.2  170  16  8  -1.8  -1.0 |  10.1  50.2  165   5  3  10.8   5.9
  5750   6.0  42.8  165  11  6   1.2   0.6 |  10.9  51.6  165   5  3  10.4   5.7
  5500   6.4  43.5  160   8  4  11.1   6.1 |  11.7  53.1  165   5  2  15.1   8.3

           03/23/2015 at 1500 MDT          |       03/23/2015 at 1800 MDT
                                           |
K index... +24.4  LI... +271.6             | K index... +20.4  LI... +270.5
CAPE... +216.0  CIN... -9.0                | CAPE... +357.6  CIN... -53.5
                                           |
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 -57.4 -71.3  265  37 19   1.9   1.1 | -57.3 -71.1  265  36 19   2.2   1.2
 45000 -54.4 -65.9  260  55 28   1.2   0.7 | -53.8 -64.8  265  52 27   1.7   0.9
 40000 -54.4 -65.9  260  60 31  -0.1  -0.0 | -53.7 -64.7  260  50 26  -0.0  -0.0
 38000 -54.7 -66.5  255  58 30  -0.9  -0.5 | -53.9 -65.0  260  49 25  -0.7  -0.4
 36000 -55.2 -67.4  245  52 27  -0.9  -0.5 | -54.3 -65.7  260  46 24  -0.7  -0.4
 34000 -55.6 -68.1  235  48 25   4.6   2.5 | -54.8 -66.6  265  43 22   2.3   1.3
 32000 -51.7 -61.1  230  45 23   6.5   3.6 | -51.5 -60.7  265  41 21   5.4   2.9
 30000 -47.0 -52.6  230  42 22   8.6   4.7 | -47.7 -53.9  270  39 20   8.0   4.4
 29000 -44.5 -48.1  230  41 21   8.5   4.7 | -45.4 -49.7  270  39 20   7.8   4.3
 28000 -41.9 -43.4  230  40 20   8.5   4.7 | -43.0 -45.4  270  39 20   7.8   4.3
 27000 -39.4 -38.9  235  39 20   8.7   4.8 | -40.7 -41.3  270  39 20   7.9   4.4
 26000 -36.7 -34.1  235  36 19   8.9   4.9 | -38.1 -36.6  270  39 20   8.6   4.7
 25000 -34.1 -29.4  240  34 17   8.9   4.9 | -35.6 -32.1  270  38 20   8.5   4.7
 24000 -31.4 -24.5  245  32 16   8.8   4.8 | -33.0 -27.4  270  38 20   8.6   4.7
 23000 -29.0 -20.2  245  30 16   7.8   4.3 | -30.6 -23.1  270  35 18   7.8   4.3
 22000 -26.7 -16.1  250  29 15   7.8   4.3 | -28.3 -18.9  265  32 16   7.8   4.3
 21000 -24.4 -11.9  255  28 14   7.8   4.3 | -26.0 -14.8  260  28 15   7.9   4.3
 20000 -22.1  -7.8  255  26 14   7.9   4.3 | -23.6 -10.5  260  31 16   7.9   4.3
 19500 -20.9  -5.6  260  26 13   7.9   4.3 | -22.5  -8.5  265  32 16   7.9   4.3
 19000 -19.8  -3.6  260  25 13   7.9   4.3 | -21.3  -6.3  265  33 17   8.0   4.4
 18500 -18.6  -1.5  260  24 12   7.9   4.4 | -20.1  -4.2  265  34 18   8.2   4.5
 18000 -17.4   0.7  260  23 12   8.1   4.4 | -18.8  -1.8  265  34 18   9.1   5.0
 17500 -16.2   2.8  260  22 11   8.1   4.5 | -17.5   0.5  265  35 18   9.2   5.0
 17000 -15.1   4.8  260  21 11   7.5   4.1 | -16.1   3.0  265  34 18   8.9   4.9
 16500 -14.0   6.8  260  21 11   7.6   4.1 | -14.8   5.4  265  33 17   8.9   4.9
 16000 -12.3   9.9  260  20 10   7.6   4.2 | -12.9   8.8  265  32 17   9.1   5.0
 15500 -11.2  11.8  260  19 10   7.7   4.2 | -11.5  11.3  265  32 16   9.1   5.0
 15000 -10.1  13.8  255  19 10   7.2   4.0 | -10.2  13.6  265  31 16   8.9   4.9
 14500  -9.0  15.8  255  18  9   7.2   3.9 |  -8.9  16.0  265  30 15   8.9   4.9
 14000  -8.0  17.6  255  18  9   7.3   4.0 |  -7.6  18.3  265  29 15   9.3   5.1
 13500  -6.9  19.6  260  17  9   7.3   4.0 |  -6.1  21.0  265  28 14   9.5   5.2
 13000  -5.8  21.6  260  16  8   7.3   4.0 |  -4.7  23.5  265  27 14   9.5   5.2
 12500  -4.8  23.4  260  16  8   7.3   4.0 |  -3.3  26.1  265  25 13   9.5   5.2
 12000  -3.7  25.3  255  15  8   7.2   3.9 |  -1.9  28.6  265  24 12   9.3   5.1
 11500  -2.7  27.1  260  14  7   7.1   3.9 |  -0.6  30.9  265  23 12   8.9   4.9
 11000  -1.6  29.1  260  13  7   6.8   3.7 |   0.8  33.4  265  21 11   8.4   4.6
 10500  -0.7  30.7  265  12  6   6.0   3.3 |   1.9  35.4  265  19 10   7.0   3.8
 10250  -0.2  31.6  265  12  6   8.4   4.6 |   2.4  36.3  265  18  9   8.9   4.9
 10000   0.5  32.9  265  11  6  10.9   6.0 |   3.2  37.8  265  16  8   9.8   5.4
  9750   1.3  34.3  265  10  5  10.2   5.6 |   3.8  38.8  270  15  8   8.1   4.5
  9500   2.1  35.8  270  10  5  10.5   5.8 |   4.4  39.9  270  14  7   8.0   4.4
  9250   2.9  37.2  270  10  5  10.1   5.5 |   5.0  41.0  270  12  6   8.0   4.4
  9000   3.6  38.5  270  10  5   9.9   5.5 |   5.6  42.1  270  11  6   7.6   4.2
  8750   4.4  39.9  270   9  5  10.3   5.6 |   6.1  43.0  270  10  5   7.5   4.1
  8500   5.2  41.4  270   9  5  10.2   5.6 |   6.7  44.1  275   9  4   7.5   4.1
  8250   5.9  42.6  270   9  5  10.6   5.8 |   7.2  45.0  275   7  4   7.8   4.3
  8000   6.7  44.1  275   8  4  10.7   5.9 |   7.8  46.0  275   5  3   8.2   4.5
  7750   7.5  45.5  275   8  4   9.5   5.2 |   8.4  47.1  270   4  2   7.3   4.0
  7500   8.2  46.8  280   8  4   9.0   4.9 |   8.8  47.8  265   2  1   6.3   3.5
  7250   8.9  48.0  285   8  4   9.0   4.9 |   9.3  48.7  240   1  1   7.9   4.3
  7000   9.5  49.1  295   8  4   8.8   4.8 |   9.9  49.8  210   1  0  10.1   5.6
  6750  10.1  50.2  300   8  4   8.5   4.7 |  10.7  51.3  200   1  0   9.7   5.3
  6500  10.7  51.3  305   7  4   8.7   4.7 |  11.4  52.5  200   1  0   9.1   5.0
  6250  11.3  52.3  310   7  4   9.7   5.3 |  12.1  53.8  195   1  0   9.9   5.4
  6000  12.1  53.8  310   7  4  10.5   5.8 |  12.8  55.0  195   1  0  10.4   5.7
  5750  12.8  55.0  310   7  4   9.1   5.0 |  13.6  56.5  190   1  0   9.7   5.3
  5500  13.5  56.3  310   7  4  10.7   5.9 |  14.3  57.7  190   1  0   9.5   5.2
________________________________________________________________________________

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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