Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211229
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0529 MST Tuesday, February 21, 2017

This forecast is for Tuesday, February 21, 2017:

If the trigger temperature of 61.6 F/16.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 564 ft/min (2.9 m/s)
   Maximum height of thermals.................. 13442 ft MSL (8157 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1000 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11823 ft MSL (6538 ft AGL)
Thermal soaring outlook for Wednesday 02/22.... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Decreasing throughout the aftern
Height of stable layer (12-18K ft MSL)......... 11944 ft MSL (6659 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 12684 ft MSL (7399 ft AGL)
Wave soaring outlook for Wednesday 02/22....... Fair

Remarks...

Sunrise/Sunset.................... 06:43:18 / 17:42:45 MST
Total possible sunshine........... 10 hr 59 min 27 sec (659 min 27 sec)
Altitude of sun at 12:13:02 MST... 39.86 degrees

Upper air data from rawinsonde observation taken on 02/21/2017 at 0500 MST

Freezing level.................. 11030 ft MSL (5745 ft AGL)
Additional freezing levels...... 11608 ft MSL (6323 ft AGL)
                                 12985 ft MSL (7700 ft AGL)
Convective condensation level... 18725 ft MSL (13440 ft AGL)
Lifted condensation level....... 18123 ft MSL (12837 ft AGL)
Lifted index.................... +1.1
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  -65.7 -86.3   255   74   38   2.4   1.3   86.3 187.3    36.0      M    M
 45000  -55.8 -68.4   270   54   28   8.2   4.5   78.1 172.5    33.5      M    M
 40000  -49.8 -57.6   270  111   57  -1.3  -0.7   64.9 148.8    27.1      M    M
 38000  -45.1 -49.2   275  110   56   8.0   4.4   63.1 145.7    26.6      M    M
 36000  -47.2 -53.0   280  108   55 -36.7 -20.2   51.7 125.0    19.3      M    M
 34000  -48.4 -55.1   290  104   54   6.8   3.8   40.6 105.0    11.9      M    M
 32000  -44.4 -47.9   295   89   46   6.7   3.7   37.9 100.3    10.3      M    M
 30000  -42.4 -44.3   295   73   37   7.3   4.0   32.8  91.0     6.7      M    M
 29000  -40.2 -40.4   290   67   34   8.1   4.4   31.9  89.5     6.1      M    M
 28000  -37.5 -35.5   290   65   34   8.9   4.9   31.4  88.6     5.8      M    M
 27000  -34.8 -30.6   290   64   33   8.9   4.9   31.1  87.9     5.6      M    M
 26000  -32.2 -26.0   290   63   32   8.9   4.9   30.8  87.5     5.5      M    M
 25000  -29.5 -21.1   290   61   31   8.9   4.9   30.7  87.3     5.5      M    M
 24000  -26.9 -16.4   290   59   30   7.3   4.0   30.2  86.4     5.1      M    M
 23000  -24.7 -12.5   290   54   28   7.2   4.0   29.1  84.4     4.2      M    M
 22000  -22.6  -8.7   290   48   25   7.2   4.0   28.1  82.6     3.5      M    M
 21000  -20.4  -4.7   295   43   22   7.2   3.9   27.3  81.1     2.8      M    M
 20000  -18.1  -0.6   295   37   19   8.5   4.7   26.6  79.9     2.3      M    M
 19500  -16.9   1.6   295   38   20   8.5   4.7   26.4  79.5     2.1      M    M
 19000  -15.6   3.9   295   40   21   8.4   4.6   26.2  79.1     1.9      M    M
 18500  -14.3   6.3   295   41   21   9.1   5.0   26.0  78.7     1.8      M    M
 18000  -12.9   8.8   295   42   21   9.1   5.0   25.8  78.5     1.7      M    M
 17500  -11.5  11.3   295   42   22   9.1   5.0   25.7  78.3     1.6      M    M
 17000   -9.5  14.9   295   42   22   9.1   5.0   25.6  78.0     1.5      M    M
 16500   -8.1  17.4   295   43   22   9.1   5.0   25.5  77.9     1.4      M    M
 16000   -6.8  19.8   295   43   22   9.1   5.0   25.4  77.8     1.4      M    M
 15500   -5.4  22.3   300   42   22   9.1   5.0   25.3  77.5     1.2      M    M
 15000   -4.0  24.8   300   41   21   9.0   5.0   25.1  77.3     1.1      M    M
 14500   -2.7  27.1   305   41   21   8.6   4.7   25.0  77.1     1.0      M    M
 14000   -1.7  28.9   305   40   21   5.8   3.2   24.5  76.2     0.6      M    M
 13500   -0.8  30.6   310   43   22   6.0   3.3   23.9  75.0    -0.0    563  2.9
 13000    0.1  32.2   310   46   24   6.0   3.3   23.3  74.0    -0.6    522  2.7
 12500    1.0  33.8   300   46   24   5.8   3.2   22.7  72.9    -1.2    481  2.4
 12000    1.7  35.1   295   46   24  -6.4  -3.5   21.9  71.5    -2.0    445  2.3
 11500   -0.7  30.7   295   38   20  -3.3  -1.8   18.1  64.5    -5.8    500  2.5
 11000    0.2  32.4   290   31   16   7.6   4.2   17.4  63.4    -6.5    461  2.3
 10500    1.4  34.5   285   32   16   8.1   4.5   17.2  62.9    -6.8    409  2.1
 10250    2.0  35.6   280   32   16   8.5   4.7   17.1  62.7    -6.9    383  1.9
 10000    2.7  36.9   280   32   17   9.0   5.0   17.0  62.6    -7.0    356  1.8
  9750    3.3  37.9   280   33   17   9.1   5.0   16.9  62.5    -7.0    328  1.7
  9500    4.0  39.2   280   33   17   9.1   5.0   16.9  62.4    -7.1    300  1.5
  9250    4.7  40.5   280   34   17   9.1   5.0   16.9  62.4    -7.1    272  1.4
  9000    5.4  41.7   280   34   17   9.1   5.0   16.8  62.3    -7.2    245  1.2
  8750    6.1  43.0   285   30   16   9.1   5.0   16.8  62.2    -7.3    217  1.1
  8500    6.7  44.1   285   27   14   9.1   5.0   16.7  62.1    -7.3    189  1.0
  8250    7.4  45.3   290   23   12   9.1   5.0   16.7  62.1    -7.4    161  0.8
  8000    8.1  46.6   295   20   10   9.1   5.0   16.7  62.0    -7.5    134  0.7
  7750    8.8  47.8   295   17    9   9.1   5.0   16.6  61.9    -7.5    106  0.5
  7500    9.5  49.1   300   15    7   9.1   5.0   16.6  61.8    -7.6     78  0.4
  7250   10.1  50.2   300   12    6   9.1   5.0   16.5  61.7    -7.7     50  0.3
  7000   10.8  51.4   305    9    5   9.1   5.0   16.5  61.6    -7.8     22  0.1
  6750   11.5  52.7   300    8    4   9.1   5.0   16.4  61.5    -7.8      M    M
  6500   12.2  54.0   295    7    4   9.2   5.1   16.3  61.4    -7.9      M    M
  6250   12.9  55.2   285    6    3   8.7   4.8   16.3  61.3    -8.0      M    M
  6000   13.5  56.3   275    5    3  10.7   5.9   16.2  61.2    -8.1      M    M
  5750   14.2  57.6   265    5    3   1.6   0.9   16.1  61.1    -8.2      M    M
  5500   13.5  56.3   250    5    3 -19.3 -10.6   14.7  58.5    -9.6      M    M

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

           02/21/2017 at 0800 MST          |       02/21/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.1        | CAPE...     0.0    LI...       +3.2
CINH...    -0.2    K Index... -18.7        | CINH...    -0.1    K Index... -13.2
                                           |
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 -64.5 -84.1  255  40 20   3.0   1.7 | -65.7 -86.3  250  45 23   3.2   1.8
 45000 -59.7 -75.5  260  48 24   4.9   2.7 | -60.6 -77.1  255  51 26   4.7   2.6
 40000 -51.9 -61.4  265  53 27   5.1   2.8 | -53.5 -64.3  260  51 26   4.7   2.6
 38000 -50.1 -58.2  270  51 26   2.6   1.4 | -51.3 -60.3  265  49 25   3.3   1.8
 36000 -48.5 -55.3  275  49 25   2.6   1.4 | -49.1 -56.4  270  47 24   3.3   1.8
 34000 -46.6 -51.9  280  47 24   4.4   2.4 | -46.6 -51.9  275  44 23   4.9   2.7
 32000 -44.0 -47.2  285  43 22   4.3   2.4 | -43.7 -46.7  275  41 21   4.9   2.7
 30000 -40.9 -41.6  285  38 19   6.7   3.7 | -40.2 -40.4  280  38 20   6.6   3.6
 29000 -38.4 -37.1  285  34 17   6.7   3.7 | -38.3 -36.9  280  36 18   6.6   3.6
 28000 -36.4 -33.5  285  30 16   6.7   3.7 | -36.3 -33.3  280  34 17   6.6   3.6
 27000 -34.3 -29.7  280  28 14   7.5   4.1 | -34.2 -29.6  280  32 16   7.7   4.2
 26000 -32.0 -25.6  285  26 13   7.5   4.1 | -31.9 -25.4  280  30 15   7.7   4.2
 25000 -29.8 -21.6  285  24 12   7.5   4.1 | -29.6 -21.3  280  28 15   7.7   4.2
 24000 -27.5 -17.5  285  22 11   8.1   4.4 | -27.3 -17.1  280  27 14   7.5   4.1
 23000 -25.1 -13.2  285  21 11   8.0   4.4 | -25.0 -13.0  280  26 13   7.5   4.1
 22000 -22.7  -8.9  285  20 10   8.0   4.4 | -22.8  -9.0  280  24 12   7.5   4.1
 21000 -20.3  -4.5  290  19 10   8.1   4.5 | -20.5  -4.9  280  23 12   7.8   4.3
 20000 -17.9  -0.2  290  18  9   8.1   4.5 | -18.1  -0.6  280  21 11   7.8   4.3
 19500 -16.7   1.9  290  18  9   8.1   4.5 | -17.0   1.4  280  21 11   7.8   4.3
 19000 -15.4   4.3  290  17  9   8.1   4.5 | -15.8   3.6  280  20 10   7.8   4.3
 18500 -14.2   6.4  290  17  9   8.2   4.5 | -14.0   6.8  280  19 10   8.0   4.4
 18000 -13.0   8.6  290  17  9   8.2   4.5 | -12.8   9.0  280  18  9   8.0   4.4
 17500 -11.8  10.8  295  17  9   8.2   4.5 | -11.6  11.1  280  18  9   8.0   4.4
 17000 -10.5  13.1  295  17  9   8.2   4.5 | -10.4  13.3  280  17  9   8.0   4.4
 16500  -9.3  15.3  295  16  8   8.2   4.5 |  -9.2  15.4  280  17  9   8.2   4.5
 16000  -8.1  17.4  295  16  8   8.4   4.6 |  -7.9  17.8  280  16  8   8.3   4.6
 15500  -6.2  20.8  295  15  8   8.4   4.6 |  -6.7  19.9  275  15  8   8.3   4.6
 15000  -4.9  23.2  295  15  8   8.4   4.6 |  -5.4  22.3  275  15  8   8.4   4.6
 14500  -3.7  25.3  295  14  7   8.4   4.6 |  -4.2  24.4  275  14  7   8.4   4.6
 14000  -2.4  27.7  295  14  7   8.5   4.7 |  -2.9  26.8  275  14  7   8.3   4.5
 13500  -1.1  30.0  300  14  7   8.5   4.7 |  -1.7  28.9  275  14  7   8.3   4.5
 13000   0.1  32.2  300  14  7   8.4   4.6 |  -0.4  31.3  275  13  7   8.2   4.5
 12500   1.4  34.5  295  14  7   8.5   4.7 |   0.8  33.4  275  13  7   8.3   4.6
 12000   2.6  36.7  295  15  8   7.8   4.3 |   2.0  35.6  270  13  7   7.7   4.2
 11500   3.8  38.8  295  16  8   8.0   4.4 |   3.1  37.6  270  14  7   7.9   4.3
 11000   4.9  40.8  295  16  8   7.1   3.9 |   4.2  39.6  270  14  7   6.8   3.7
 10500   5.9  42.6  295  17  9   7.0   3.8 |   5.2  41.4  270  14  7   6.8   3.7
 10250   6.5  43.7  290  18  9   7.5   4.1 |   5.8  42.4  270  15  8   7.1   3.9
 10000   7.0  44.6  290  18  9   6.5   3.6 |   6.3  43.3  270  15  8   6.5   3.6
  9750   7.4  45.3  290  19 10   5.3   2.9 |   6.7  44.1  270  15  8   5.7   3.1
  9500   7.8  46.0  290  20 10   5.6   3.1 |   7.1  44.8  270  16  8   6.0   3.3
  9250   8.2  46.8  290  21 11   6.0   3.3 |   7.6  45.7  270  16  8   5.7   3.1
  9000   8.6  47.5  290  21 11   4.5   2.5 |   8.0  46.4  270  17  9   5.5   3.0
  8750   8.8  47.8  285  22 11   2.5   1.3 |   8.4  47.1  270  17  9   5.7   3.1
  8500   9.0  48.2  285  23 12   2.7   1.5 |   8.8  47.8  270  17  9   5.6   3.1
  8250   9.1  48.4  285  24 12   3.1   1.7 |   9.1  48.4  270  17  9   5.1   2.8
  8000   9.4  48.9  285  24 12   3.2   1.7 |   9.5  49.1  275  17  9   5.0   2.8
  7750   9.5  49.1  285  24 12   1.5   0.8 |   9.8  49.6  275  16  8   5.2   2.9
  7500   9.5  49.1  280  23 12   2.0   1.1 |  10.2  50.4  275  15  8   6.9   3.8
  7250   9.7  49.5  280  23 12   4.4   2.4 |  10.8  51.4  275  15  8   9.1   5.0
  7000  10.1  50.2  280  22 11   5.0   2.8 |  11.5  52.7  275  15  7   9.2   5.1
  6750  10.4  50.7  275  21 11   3.0   1.7 |  12.1  53.8  275  14  7   9.4   5.2
  6500  10.5  50.9  275  19 10   2.7   1.5 |  12.9  55.2  270  13  7  10.0   5.5
  6250  10.8  51.4  275  17  9   3.7   2.0 |  13.6  56.5  275  13  7  10.4   5.7
  6000  11.0  51.8  275  16  8   4.3   2.4 |  14.4  57.9  275  12  6   9.5   5.2
  5750  11.3  52.3  270  14  7   1.1   0.6 |  15.2  59.4  275  12  6  12.7   7.0
  5500  11.0  51.8  265   9  5  -8.8  -4.9 |  16.4  61.5  270  10  5  21.2  11.6

           02/21/2017 at 1400 MST          |       02/21/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +2.8        | CAPE...     0.0    LI...       +2.3
CINH...     0.0    K Index...  -6.9        | CINH...    -0.0    K Index...  -2.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.5 -85.9  250  48 25   3.8   2.1 | -65.5 -85.9  250  48 25   4.1   2.2
 45000 -59.8 -75.6  255  53 27   4.0   2.2 | -59.2 -74.6  255  55 28   3.4   1.9
 40000 -53.8 -64.8  255  51 26   4.0   2.2 | -54.1 -65.4  255  54 28   3.4   1.9
 38000 -51.9 -61.4  260  50 26   2.8   1.5 | -52.7 -62.9  255  53 27   1.9   1.0
 36000 -50.3 -58.5  260  48 25   2.8   1.5 | -51.6 -60.9  260  51 26   1.9   1.0
 34000 -47.7 -53.9  265  46 24   5.3   2.9 | -49.9 -57.8  260  49 25   5.4   3.0
 32000 -44.5 -48.1  270  45 23   5.3   2.9 | -46.6 -51.9  260  46 24   5.5   3.0
 30000 -40.9 -41.6  270  42 22   7.0   3.8 | -42.3 -44.1  260  42 22   8.0   4.4
 29000 -38.8 -37.8  270  41 21   7.0   3.8 | -39.9 -39.8  260  40 20   8.0   4.4
 28000 -36.7 -34.1  270  39 20   7.0   3.8 | -37.5 -35.5  260  37 19   8.0   4.4
 27000 -34.6 -30.3  270  37 19   7.6   4.2 | -35.2 -31.4  260  35 18   7.9   4.3
 26000 -32.3 -26.1  270  35 18   7.6   4.2 | -32.8 -27.0  260  34 18   7.9   4.3
 25000 -30.0 -22.0  270  33 17   7.6   4.2 | -30.4 -22.7  260  33 17   7.9   4.3
 24000 -27.7 -17.9  270  31 16   7.5   4.1 | -28.1 -18.6  260  31 16   7.8   4.3
 23000 -25.5 -13.9  270  29 15   7.5   4.1 | -25.8 -14.4  260  30 15   7.8   4.3
 22000 -23.3  -9.9  270  27 14   7.5   4.1 | -23.4 -10.1  260  28 14   7.8   4.3
 21000 -21.1  -6.0  270  25 13   7.3   4.0 | -21.2  -6.2  260  26 13   6.6   3.6
 20000 -18.9  -2.0  265  23 12   7.3   4.0 | -19.2  -2.6  255  24 12   6.6   3.6
 19500 -17.8  -0.0  265  22 11   7.3   4.0 | -18.2  -0.8  255  23 12   6.6   3.6
 19000 -16.7   1.9  265  21 11   7.2   3.9 | -17.2   1.0  255  22 11   6.5   3.6
 18500 -14.9   5.2  265  20 10   8.2   4.5 | -16.1   3.0  255  21 11   8.2   4.5
 18000 -13.7   7.3  265  19 10   8.2   4.5 | -14.9   5.2  255  20 11   8.1   4.4
 17500 -12.4   9.7  260  18  9   8.4   4.6 | -13.7   7.3  255  20 10   8.2   4.5
 17000 -11.1  12.0  260  18  9   8.4   4.6 | -11.8  10.8  250  19 10   8.3   4.6
 16500  -9.9  14.2  260  17  9   8.6   4.7 | -10.6  12.9  250  19 10   8.3   4.6
 16000  -8.6  16.5  255  16  8   8.6   4.7 |  -9.3  15.3  250  19 10   8.4   4.6
 15500  -7.3  18.9  255  16  8   8.6   4.7 |  -8.1  17.4  250  19 10   8.4   4.6
 15000  -6.0  21.2  255  16  8   8.3   4.6 |  -6.8  19.8  250  19 10   8.5   4.7
 14500  -4.8  23.4  250  16  8   8.3   4.6 |  -5.6  21.9  250  18  9   8.5   4.7
 14000  -3.6  25.5  250  16  8   7.9   4.4 |  -4.3  24.3  250  18  9   8.4   4.6
 13500  -2.4  27.7  250  16  8   8.0   4.4 |  -3.0  26.6  250  18  9   8.4   4.6
 13000  -1.2  29.8  250  16  8   7.5   4.1 |  -1.8  28.8  250  18  9   8.3   4.5
 12500  -0.1  31.8  250  15  8   7.6   4.2 |  -0.6  30.9  250  18  9   8.3   4.6
 12000   1.0  33.8  250  15  8   7.6   4.2 |   0.7  33.3  250  17  9   7.9   4.3
 11500   2.1  35.8  250  15  8   7.6   4.1 |   1.8  35.2  250  17  9   7.9   4.4
 11000   3.3  37.9  255  15  8   7.9   4.4 |   2.9  37.2  250  16  8   7.0   3.8
 10500   4.5  40.1  255  14  7   8.0   4.4 |   3.9  39.0  250  15  8   6.7   3.7
 10250   5.1  41.2  255  14  7   7.9   4.4 |   4.4  39.9  250  14  7   7.9   4.3
 10000   5.6  42.1  255  14  7   7.2   4.0 |   5.1  41.2  250  13  7   8.1   4.5
  9750   6.1  43.0  255  14  7   6.7   3.7 |   5.6  42.1  250  13  7   7.2   4.0
  9500   6.6  43.9  255  13  7   6.9   3.8 |   6.1  43.0  250  12  6   7.2   3.9
  9250   7.1  44.8  255  13  7   6.9   3.8 |   6.6  43.9  250  12  6   8.4   4.6
  9000   7.6  45.7  260  13  7   7.5   4.1 |   7.3  45.1  250  10  5   9.0   4.9
  8750   8.2  46.8  260  12  6   7.7   4.2 |   7.9  46.2  245  10  5   8.1   4.5
  8500   8.7  47.7  260  12  6   7.8   4.3 |   8.5  47.3  245  10  5   8.3   4.6
  8250   9.3  48.7  260  12  6   9.6   5.2 |   9.2  48.6  245  10  5   9.4   5.1
  8000  10.1  50.2  260  11  6  10.3   5.6 |   9.9  49.8  245   9  5   9.9   5.4
  7750  10.8  51.4  260  11  6   8.9   4.9 |  10.6  51.1  245   9  4   8.7   4.8
  7500  11.5  52.7  260  11  6   9.3   5.1 |  11.2  52.2  245   9  4   8.9   4.9
  7250  12.2  54.0  260  11  5  10.5   5.8 |  11.9  53.4  245   8  4   9.8   5.4
  7000  13.0  55.4  260  10  5  10.7   5.9 |  12.7  54.9  245   8  4  10.1   5.5
  6750  13.8  56.8  260  10  5   9.2   5.0 |  13.4  56.1  240   8  4   9.0   4.9
  6500  14.4  57.9  260  10  5   9.7   5.3 |  14.0  57.2  245   8  4   9.2   5.0
  6250  15.3  59.5  260  10  5  11.4   6.2 |  14.8  58.6  240   7  4  10.0   5.5
  6000  16.1  61.0  260   9  5  10.2   5.6 |  15.5  59.9  240   7  3  10.1   5.5
  5750  16.9  62.4  260   9  5  12.4   6.8 |  16.2  61.2  240   6  3   8.7   4.8
  5500  18.0  64.4  260   8  4  19.8  10.9 |  16.7  62.1  245   5  3   5.5   3.0
________________________________________________________________________________

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.

CINH (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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