Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250118
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1918 MDT Thursday, April 24, 2014

This forecast is for Friday, April 25, 2014:

If the trigger temperature of 61.8 F/16.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1370 ft/min (7.0 m/s)
   Maximum height of thermals.................. 20496 ft MSL (15209 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 0900 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................. 17618 ft MSL (12330 ft AGL)
Thermal soaring outlook for Saturday 04/26..... Excellent

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 NVA
Potential height of wave....................... 39160 ft MSL (33873 ft AGL)
Wave soaring outlook for Saturday 04/26........ Poor

Remarks... None

Sunrise/Sunset.................... 06:07:47 / 19:46:50 MDT
Total possible sunshine........... 13 hr 39 min 3 sec (819 min 3 sec)
Altitude of sun at 12:57:28 MDT... 63.58 degrees

Upper air data from numerical model forecast valid on 04/25/2014 at 0600 MDT

Freezing level.................. 11292 ft MSL (6005 ft AGL)
Convective condensation level... 17446 ft MSL (12159 ft AGL)
Lifted condensation level....... 19030 ft MSL (13743 ft AGL)
Lifted index.................... -0.9
K index......................... +12.7

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  -59.8 -75.6   270   31   16   1.3   0.7      M     M       M      M    M
 45000  -57.8 -72.0   275   52   27   1.7   0.9      M     M       M      M    M
 40000  -63.0 -81.4   275   69   36  -3.5  -1.9      M     M       M      M    M
 38000  -61.8 -79.2   275   70   36   6.5   3.6      M     M       M      M    M
 36000  -57.9 -72.2   275   67   34   6.5   3.6      M     M       M      M    M
 34000  -53.8 -64.8   275   63   33   8.5   4.6      M     M       M      M    M
 32000  -48.7 -55.7   275   60   31   8.5   4.6      M     M       M      M    M
 30000  -43.7 -46.7   275   57   30   8.2   4.5   32.1  89.9     4.9      M    M
 29000  -41.3 -42.3   275   57   29   8.2   4.5   31.5  88.6     4.5      M    M
 28000  -38.8 -37.8   275   57   29   8.2   4.5   30.9  87.6     4.1      M    M
 27000  -35.7 -32.3   275   57   29   8.3   4.6   30.3  86.5     3.7      M    M
 26000  -33.2 -27.8   275   55   28   8.3   4.6   29.6  85.4     3.2      M    M
 25000  -30.7 -23.3   275   54   28   8.3   4.6   29.1  84.4     2.8      M    M
 24000  -28.3 -18.9   275   52   27   7.9   4.3   28.7  83.6     2.5      M    M
 23000  -26.0 -14.8   275   49   25   7.6   4.2   27.8  82.0     1.8      M    M
 22000  -23.7 -10.7   280   46   23   7.6   4.2   27.0  80.7     1.2      M    M
 21000  -21.5  -6.7   280   43   22   6.6   3.6   26.3  79.3     0.5      M    M
 20000  -19.6  -3.3   280   40   21   6.7   3.7   25.1  77.2    -0.5   1327  6.7
 19500  -18.6  -1.5   280   39   20   6.7   3.7   24.6  76.2    -1.0   1282  6.5
 19000  -17.6   0.3   280   37   19   6.7   3.7   24.1  75.3    -1.4   1238  6.3
 18500  -16.6   2.1   280   36   19   6.2   3.4   23.6  74.4    -1.9   1195  6.1
 18000  -15.7   3.7   275   35   18   6.1   3.3   22.9  73.2    -2.5   1153  5.9
 17500  -14.9   5.2   275   35   18   6.2   3.4   22.3  72.1    -3.1   1112  5.7
 17000  -13.9   7.0   275   34   18   7.0   3.9   21.7  71.1    -3.6   1068  5.4
 16500  -12.9   8.8   275   33   17   6.9   3.8   21.3  70.3    -4.0   1023  5.2
 16000  -11.8  10.8   275   32   17   7.8   4.3   20.9  69.6    -4.5    976  5.0
 15500  -10.7  12.7   275   31   16   7.8   4.3   20.5  68.9    -4.8    927  4.7
 15000   -9.5  14.9   275   30   16   8.3   4.6   20.2  68.4    -5.1    878  4.5
 14500   -8.2  17.2   275   29   15   8.6   4.7   20.0  68.1    -5.3    824  4.2
 14000   -6.3  20.7   275   26   13   8.3   4.6   19.8  67.6    -5.6    745  3.8
 13500   -5.1  22.8   275   24   12   8.3   4.6   19.5  67.1    -5.9    693  3.5
 13000   -3.8  25.2   275   22   11   8.0   4.4   19.3  66.7    -6.1    641  3.3
 12500   -2.6  27.3   275   20   10   7.9   4.4   19.0  66.2    -6.4    591  3.0
 12000   -1.5  29.3   275   17    9   7.8   4.3   18.7  65.6    -6.7    541  2.7
 11500   -0.3  31.5   270   15    8   7.7   4.2   18.4  65.0    -7.1    492  2.5
 11000    0.8  33.4   265   12    6   6.8   3.7   18.0  64.4    -7.5    443  2.3
 10500    1.8  35.2   260   10    5   5.5   3.0   17.5  63.4    -8.0    400  2.0
 10250    2.2  36.0   255    9    5   9.4   5.2   17.2  63.0    -8.3    378  1.9
 10000    3.1  37.6   245    8    4  10.3   5.7   17.3  63.2    -8.2    345  1.8
  9750    3.7  38.7   240    8    4   7.0   3.8   17.2  62.9    -8.4    321  1.6
  9500    4.2  39.6   230    7    4   8.2   4.5   17.0  62.6    -8.5    296  1.5
  9250    4.8  40.6   220    7    4   6.9   3.8   16.9  62.4    -8.7    271  1.4
  9000    5.3  41.5   210    7    3   7.1   3.9   16.6  61.9    -9.0    249  1.3
  8750    5.9  42.6   205    7    3   8.3   4.6   16.5  61.7    -9.1    224  1.1
  8500    6.5  43.7   200    6    3   8.0   4.4   16.4  61.4    -9.3    198  1.0
  8250    7.1  44.8   195    7    3   8.3   4.5   16.2  61.2    -9.4    173  0.9
  8000    7.7  45.9   190    6    3   8.0   4.4   16.1  61.0    -9.6    147  0.7
  7750    8.3  46.9   190    6    3   7.0   3.8   15.9  60.7    -9.8    123  0.6
  7500    8.8  47.8   190    6    3   6.6   3.6   15.7  60.3   -10.0    101  0.5
  7250    9.3  48.7   190    6    3   7.0   3.9   15.5  59.9   -10.3     78  0.4
  7000    9.8  49.6   190    5    3   6.7   3.6   15.3  59.5   -10.5     55  0.3
  6750   10.3  50.5   190    5    3   8.5   4.6   15.1  59.1   -10.7     32  0.2
  6500   10.9  51.6   190    5    2   1.9   1.1   14.9  58.8   -11.0      9  0.0
  6250   10.5  50.9   195    5    3  -9.5  -5.2   13.8  56.8   -12.1     14  0.1
  6000    9.7  49.5   205    5    3  -9.9  -5.4   12.2  54.0   -13.7     31  0.2
  5750    8.8  47.8   215    6    3 -16.0  -8.8   10.7  51.2   -15.3     50  0.3
  5500    6.7  44.1   220    8    4 -39.3 -21.6    8.0  46.3   -18.2    105  0.5

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

           04/25/2014 at 0900 MDT          |       04/25/2014 at 1200 MDT
                                           |
K index... +7.2  LI... +4.2                | K index... +5.9  LI... +1.8
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -60.3 -76.5  265  28 14   0.2   0.1 | -60.8 -77.4  260  29 15   0.2   0.1
 45000 -60.0 -76.0  270  50 26   0.2   0.1 | -60.5 -76.9  270  50 26   0.1   0.0
 40000 -63.4 -82.1  270  67 34  -2.2  -1.2 | -62.5 -80.5  265  64 33  -1.4  -0.7
 38000 -61.7 -79.1  270  68 35   6.7   3.7 | -60.8 -77.4  265  66 34   6.2   3.4
 36000 -57.6 -71.7  270  66 34   6.7   3.7 | -57.0 -70.6  265  64 33   6.2   3.4
 34000 -53.3 -63.9  270  63 33   8.7   4.8 | -52.9 -63.2  260  62 32   8.8   4.8
 32000 -48.1 -54.6  270  61 31   8.8   4.8 | -47.6 -53.7  260  59 30   8.8   4.9
 30000 -42.9 -45.2  270  58 30   8.0   4.4 | -42.5 -44.5  260  55 28   7.9   4.3
 29000 -40.5 -40.9  265  57 29   8.0   4.4 | -40.1 -40.2  255  53 27   7.9   4.4
 28000 -38.1 -36.6  265  56 29   8.0   4.4 | -37.1 -34.8  255  49 25   7.9   4.4
 27000 -35.1 -31.2  265  54 28   8.0   4.4 | -34.8 -30.6  255  47 24   7.6   4.2
 26000 -32.7 -26.9  265  52 27   8.0   4.4 | -32.5 -26.5  255  44 23   7.6   4.2
 25000 -30.3 -22.5  265  50 26   8.0   4.4 | -30.2 -22.4  255  41 21   7.6   4.2
 24000 -28.0 -18.4  265  48 25   7.9   4.3 | -28.0 -18.4  255  38 20   7.6   4.2
 23000 -25.6 -14.1  265  46 23   7.8   4.3 | -25.7 -14.3  255  37 19   7.6   4.2
 22000 -23.3  -9.9  265  43 22   7.9   4.3 | -23.4 -10.1  255  37 19   7.6   4.2
 21000 -21.0  -5.8  265  41 21   6.8   3.7 | -21.2  -6.2  255  36 18   7.4   4.0
 20000 -19.0  -2.2  265  39 20   6.9   3.8 | -19.0  -2.2  255  35 18   7.4   4.1
 19500 -17.9  -0.2  265  38 20   6.9   3.8 | -17.9  -0.2  255  35 18   7.4   4.1
 19000 -16.9   1.6  265  38 19   6.9   3.8 | -16.8   1.8  255  35 18   7.4   4.1
 18500 -15.9   3.4  265  37 19   6.6   3.6 | -15.7   3.7  255  34 18   7.3   4.0
 18000 -15.0   5.0  265  36 19   6.5   3.6 | -14.7   5.5  255  34 17   7.3   4.0
 17500 -14.0   6.8  265  36 18   6.5   3.6 | -13.6   7.5  255  33 17   7.3   4.0
 17000 -13.1   8.4  265  35 18   6.4   3.5 | -12.5   9.5  255  32 16   7.4   4.0
 16500 -12.2  10.0  265  33 17   6.3   3.5 | -11.4  11.5  260  31 16   7.3   4.0
 16000 -11.2  11.8  270  32 16   7.6   4.2 | -10.3  13.5  260  30 16   7.9   4.3
 15500 -10.0  14.0  265  29 15   7.6   4.2 |  -9.1  15.6  260  29 15   7.9   4.4
 15000  -8.9  16.0  265  27 14   8.0   4.4 |  -7.9  17.8  260  28 15   8.2   4.5
 14500  -7.6  18.3  265  25 13   8.2   4.5 |  -6.7  19.9  260  26 13   8.3   4.6
 14000  -5.8  21.6  260  21 11   8.1   4.5 |  -4.8  23.4  255  23 12   8.4   4.6
 13500  -4.6  23.7  255  19 10   8.1   4.5 |  -3.6  25.5  255  21 11   8.4   4.6
 13000  -3.4  25.9  250  18  9   7.9   4.3 |  -2.3  27.9  250  20 10   8.7   4.8
 12500  -2.2  28.0  240  17  9   7.8   4.3 |  -1.0  30.2  245  19 10   8.8   4.8
 12000  -1.1  30.0  235  16  8   7.8   4.3 |   0.3  32.5  245  19 10   8.4   4.6
 11500   0.1  32.2  230  15  8   7.7   4.2 |   1.5  34.7  235  19 10   8.2   4.5
 11000   1.2  34.2  220  15  8   7.2   4.0 |   2.7  36.9  230  19 10   7.3   4.0
 10500   2.3  36.1  215  15  8   6.3   3.4 |   3.7  38.7  225  19 10   6.2   3.4
 10250   2.8  37.0  210  15  8  10.2   5.6 |   4.2  39.6  220  19 10   9.4   5.2
 10000   3.7  38.7  205  16  8  11.1   6.1 |   5.1  41.2  215  18  9   9.8   5.4
  9750   4.3  39.7  205  16  8   7.6   4.2 |   5.6  42.1  210  17  9   6.9   3.8
  9500   4.9  40.8  200  16  8   8.7   4.8 |   6.1  43.0  200  16  8   7.6   4.2
  9250   5.6  42.1  195  16  8   7.9   4.3 |   6.7  44.1  195  16  8   7.9   4.3
  9000   6.1  43.0  190  16  8   7.4   4.0 |   7.3  45.1  190  16  8   8.8   4.8
  8750   6.7  44.1  190  15  8   7.6   4.1 |   7.9  46.2  190  15  8   9.1   5.0
  8500   7.2  45.0  185  15  8   7.4   4.0 |   8.6  47.5  185  15  8   8.5   4.7
  8250   7.8  46.0  180  15  8   7.9   4.3 |   9.2  48.6  185  15  8  10.6   5.8
  8000   8.4  47.1  175  14  7   7.9   4.3 |  10.1  50.2  180  14  7  11.5   6.3
  7750   8.9  48.0  175  13  7   6.8   3.7 |  10.8  51.4  180  14  7   9.4   5.1
  7500   9.4  48.9  175  13  7   6.5   3.6 |  11.5  52.7  180  14  7   8.7   4.8
  7250   9.9  49.8  170  12  6   6.9   3.8 |  12.2  54.0  180  14  7  10.3   5.6
  7000  10.4  50.7  170  12  6   6.9   3.8 |  13.0  55.4  180  14  7  11.4   6.2
  6750  10.9  51.6  170  12  6   6.9   3.8 |  13.8  56.8  180  13  7   9.6   5.3
  6500  11.4  52.5  165  13  6   4.2   2.3 |  14.5  58.1  180  13  7   9.5   5.2
  6250  11.5  52.7  165  12  6   0.2   0.1 |  15.3  59.5  180  13  7  10.7   5.8
  6000  11.4  52.5  170  10  5  -0.8  -0.4 |  16.1  61.0  180  12  6  11.4   6.3
  5750  11.2  52.2  170   9  4  -1.4  -0.7 |  16.9  62.4  180  12  6   9.3   5.1
  5500  11.1  52.0  175   5  3   4.2   2.3 |  17.6  63.7  180  11  6  13.0   7.1

           04/25/2014 at 1500 MDT          |       04/25/2014 at 1800 MDT
                                           |
K index... +13.5  LI... +1.0               | K index... +15.6  LI... +0.1
CAPE... 0.0  CIN... -0.1                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -61.6 -78.9  265  32 16  -0.8  -0.4 | -61.8 -79.2  265  30 15  -1.3  -0.7
 45000 -62.8 -81.0  265  57 29  -0.7  -0.4 | -63.7 -82.7  265  58 30  -0.8  -0.4
 40000 -62.6 -80.7  265  67 34   0.1   0.1 | -62.3 -80.1  260  79 41   0.9   0.5
 38000 -60.1 -76.2  265  65 33   6.7   3.7 | -59.7 -75.5  260  76 39   6.4   3.5
 36000 -56.1 -69.0  265  60 31   6.7   3.7 | -55.8 -68.4  260  67 34   6.4   3.5
 34000 -51.9 -61.4  265  55 29   8.4   4.6 | -51.6 -60.9  260  59 30   8.5   4.7
 32000 -46.8 -52.2  265  54 28   8.4   4.6 | -46.5 -51.7  260  55 28   8.5   4.7
 30000 -41.8 -43.2  265  52 27   8.2   4.5 | -41.4 -42.5  260  51 27   8.3   4.6
 29000 -39.4 -38.9  265  51 26   8.2   4.5 | -39.0 -38.2  260  50 26   8.3   4.5
 28000 -36.3 -33.3  265  49 25   8.2   4.5 | -36.5 -33.7  265  49 25   8.3   4.5
 27000 -33.9 -29.0  260  47 24   7.8   4.3 | -33.4 -28.1  265  48 25   7.7   4.3
 26000 -31.5 -24.7  260  46 24   7.9   4.3 | -31.1 -24.0  260  48 25   7.8   4.3
 25000 -29.2 -20.6  260  45 23   7.9   4.3 | -28.8 -19.8  260  48 24   7.8   4.3
 24000 -26.8 -16.2  260  44 23   7.7   4.2 | -26.5 -15.7  260  47 24   7.1   3.9
 23000 -24.6 -12.3  260  42 22   7.6   4.2 | -24.4 -11.9  255  45 23   6.9   3.8
 22000 -22.3  -8.1  260  41 21   7.6   4.2 | -22.4  -8.3  255  43 22   6.9   3.8
 21000 -20.1  -4.2  260  39 20   6.2   3.4 | -20.3  -4.5  255  41 21   6.9   3.8
 20000 -18.3  -0.9  255  38 19   6.3   3.4 | -18.3  -0.9  250  36 19   6.9   3.8
 19500 -17.4   0.7  255  37 19   6.3   3.4 | -17.3   0.9  250  34 18   7.0   3.8
 19000 -16.4   2.5  255  37 19   6.3   3.4 | -16.3   2.7  250  32 17   7.0   3.8
 18500 -15.5   4.1  255  36 18   7.2   3.9 | -15.2   4.6  245  30 16   8.2   4.5
 18000 -14.4   6.1  255  33 17   7.5   4.1 | -13.9   7.0  245  29 15   8.6   4.7
 17500 -13.3   8.1  250  30 16   7.6   4.2 | -12.7   9.1  240  28 14   8.6   4.7
 17000 -12.1  10.2  250  28 14   8.0   4.4 | -11.4  11.5  235  27 14   8.1   4.4
 16500 -10.9  12.4  245  26 13   8.0   4.4 | -10.2  13.6  235  27 14   8.1   4.4
 16000  -9.8  14.4  245  24 12   7.8   4.3 |  -9.0  15.8  230  26 13   8.6   4.7
 15500  -8.6  16.5  240  23 12   7.8   4.3 |  -7.7  18.1  230  25 13   8.7   4.8
 15000  -7.5  18.5  235  22 11   8.4   4.6 |  -6.4  20.5  225  25 13   9.0   4.9
 14500  -5.5  22.1  230  21 11   8.9   4.9 |  -5.1  22.8  225  24 12   9.2   5.1
 14000  -4.2  24.4  225  20 10   9.1   5.0 |  -3.0  26.6  220  23 12   9.5   5.2
 13500  -2.8  27.0  225  20 10   9.2   5.0 |  -1.6  29.1  220  22 12   9.6   5.3
 13000  -1.4  29.5  220  19 10   9.5   5.2 |  -0.1  31.8  220  22 11   9.4   5.2
 12500   0.0  32.0  215  18  9   9.6   5.3 |   1.2  34.2  215  21 11   9.3   5.1
 12000   1.4  34.5  215  18  9   9.5   5.2 |   2.6  36.7  215  21 11   9.5   5.2
 11500   2.8  37.0  210  17  9   9.3   5.1 |   4.1  39.4  210  20 10   9.8   5.4
 11000   4.2  39.6  210  16  8   8.9   4.9 |   5.5  41.9  210  19 10   9.5   5.2
 10500   5.5  41.9  205  16  8   8.2   4.5 |   6.9  44.4  205  18  9   9.0   5.0
 10250   6.1  43.0  205  15  8  10.9   6.0 |   7.6  45.7  205  18  9   9.4   5.2
 10000   7.1  44.8  205  15  8  11.7   6.4 |   8.3  46.9  205  17  9  10.1   5.5
  9750   7.8  46.0  205  15  8   9.5   5.2 |   9.1  48.4  205  17  9  10.1   5.6
  9500   8.6  47.5  205  15  8  10.5   5.8 |   9.8  49.6  200  16  8  10.7   5.9
  9250   9.3  48.7  205  14  7   8.6   4.7 |  10.6  51.1  200  16  8   8.6   4.7
  9000   9.9  49.8  205  14  7   8.6   4.7 |  11.2  52.2  200  16  8   8.2   4.5
  8750  10.6  51.1  205  14  7  10.5   5.7 |  11.9  53.4  200  16  8  10.3   5.6
  8500  11.4  52.5  200  14  7   9.6   5.3 |  12.6  54.7  200  15  8   9.2   5.1
  8250  12.1  53.8  200  14  7  11.1   6.1 |  13.3  55.9  200  15  8  11.6   6.4
  8000  13.0  55.4  205  14  7  11.0   6.1 |  14.3  57.7  200  15  7  11.4   6.3
  7750  13.7  56.7  205  13  7   9.2   5.1 |  15.0  59.0  200  14  7   8.6   4.7
  7500  14.4  57.9  205  13  7   9.0   4.9 |  15.6  60.1  200  14  7   8.7   4.8
  7250  15.1  59.2  205  13  7  10.1   5.6 |  16.3  61.3  195  14  7   9.0   5.0
  7000  16.0  60.8  205  13  7  11.2   6.2 |  17.0  62.6  200  13  7   9.9   5.4
  6750  16.7  62.1  205  13  7  10.0   5.5 |  17.7  63.9  200  13  7  10.0   5.5
  6500  17.5  63.5  205  12  6   9.3   5.1 |  18.4  65.1  195  13  7   9.7   5.3
  6250  18.2  64.8  205  12  6  10.6   5.8 |  19.2  66.6  195  13  6  10.1   5.5
  6000  19.0  66.2  205  12  6  11.9   6.5 |  19.9  67.8  195  12  6  10.5   5.8
  5750  19.9  67.8  205  11  6  10.4   5.7 |  20.7  69.3  195  11  6  10.3   5.6
  5500  20.7  69.3  205  10  5  14.3   7.9 |  21.5  70.7  195   9  5  10.7   5.9
________________________________________________________________________________

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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