Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210017
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1717 MST Tuesday, January 20, 2015

This forecast is for Wednesday, January 21, 2015:

If the trigger temperature of 33.7 F/1.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6720 ft MSL (1433 ft AGL)

Forecast maximum temperature................... 29.0 F/-2.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Thursday 01/22..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 33409 ft MSL (28122 ft AGL)
Wave soaring outlook for Thursday 01/22........ Poor

Remarks...

Sunrise/Sunset.................... 07:15:47 / 17:04:50 MST
Total possible sunshine........... 9 hr 49 min 2 sec (589 min 2 sec)
Altitude of sun at 12:10:42 MST... 30.45 degrees

Upper air data from numerical model forecast valid on 01/21/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 8468 ft MSL (3181 ft AGL)
Lifted condensation level....... 7852 ft MSL (2565 ft AGL)
Lifted index.................... +10.8
K index......................... +7.9

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  -56.3 -69.3   290   39   20   0.9   0.5      M     M       M      M    M
 45000  -55.0 -67.0   285   47   24   0.9   0.5      M     M       M      M    M
 40000  -55.0 -67.0   275   60   31  -0.2  -0.1      M     M       M      M    M
 38000  -55.1 -67.2   275   66   34  -1.4  -0.7      M     M       M      M    M
 36000  -56.3 -69.3   270   73   38  -2.0  -1.1      M     M       M      M    M
 34000  -57.7 -71.9   265   82   42  -2.3  -1.2      M     M       M      M    M
 32000  -55.7 -68.3   265   83   43   4.7   2.6      M     M       M      M    M
 30000  -52.9 -63.2   265   82   42   4.3   2.4      M     M       M      M    M
 29000  -50.6 -59.1   265   79   41   8.6   4.7   22.3  72.2    18.1      M    M
 28000  -48.0 -54.4   270   75   39   8.6   4.7   21.8  71.3    17.9      M    M
 27000  -45.4 -49.7   270   71   36   8.6   4.7   21.4  70.6    17.9      M    M
 26000  -43.0 -45.4   270   66   34   7.1   3.9   20.8  69.5    17.6      M    M
 25000  -40.9 -41.6   270   61   31   7.1   3.9   19.7  67.5    16.9      M    M
 24000  -38.8 -37.8   275   56   29   7.1   3.9   18.8  65.8    16.4      M    M
 23000  -36.6 -33.9   275   52   27   7.9   4.3   17.9  64.3    15.9      M    M
 22000  -34.2 -29.6   275   49   25   7.8   4.3   17.2  62.9    15.5      M    M
 21000  -31.9 -25.4   280   46   24   7.9   4.3   16.6  61.8    15.1      M    M
 20000  -29.6 -21.3   280   44   22   7.4   4.1   15.7  60.3    14.6      M    M
 19500  -28.5 -19.3   280   42   22   7.4   4.1   15.3  59.5    14.3      M    M
 19000  -27.4 -17.3   280   41   21   7.4   4.1   14.9  58.8    14.0      M    M
 18500  -26.3 -15.3   280   39   20   7.4   4.1   14.5  58.1    13.8      M    M
 18000  -25.2 -13.4   280   38   20   7.2   4.0   14.1  57.4    13.5      M    M
 17500  -24.1 -11.4   280   37   19   7.1   3.9   13.7  56.6    13.2      M    M
 17000  -22.6  -8.7   280   35   18   6.6   3.6   13.0  55.3    12.7      M    M
 16500  -21.6  -6.9   280   33   17   6.5   3.6   12.4  54.3    12.3      M    M
 16000  -20.6  -5.1   280   31   16   6.4   3.5   11.9  53.4    11.9      M    M
 15500  -19.7  -3.5   275   28   15   6.2   3.4   11.3  52.3    11.4      M    M
 15000  -18.7  -1.7   275   26   13   5.8   3.2   10.7  51.2    10.9      M    M
 14500  -18.0  -0.4   270   24   12   5.0   2.8    9.9  49.8    10.3      M    M
 14000  -17.3   0.9   265   22   11   4.9   2.7    9.1  48.4     9.6      M    M
 13500  -16.6   2.1   260   20   10   4.0   2.2    8.2  46.8     8.8      M    M
 13000  -16.1   3.0   255   18    9   4.5   2.5    7.3  45.1     8.0      M    M
 12500  -15.2   4.6   250   16    8   6.7   3.7    6.7  44.0     7.4      M    M
 12000  -14.2   6.4   250   14    7   6.0   3.3    6.2  43.1     7.0      M    M
 11500  -13.6   7.5   245   13    7   3.2   1.7    5.2  41.4     6.1      M    M
 11000  -13.1   8.4   235   11    6   3.8   2.1    4.2  39.6     5.2      M    M
 10500  -12.4   9.7   225    8    4   4.7   2.6    3.4  38.1     4.4      M    M
 10250  -12.1  10.2   215    7    4   5.4   3.0    3.0  37.4     4.1      M    M
 10000  -11.7  10.9   205    6    3   2.6   1.4    2.6  36.7     3.7      M    M
  9750  -11.6  11.1   200    6    3   2.9   1.6    1.9  35.5     3.1      M    M
  9500  -11.2  11.8   185    5    2   6.0   3.3    1.6  34.9     2.8      M    M
  9250  -10.8  12.6   165    4    2   5.1   2.8    1.2  34.2     2.4      M    M
  9000  -10.5  13.1   145    4    2   4.0   2.2    0.9  33.5     2.1      M    M
  8750  -10.2  13.6   125    4    2   5.6   3.0    0.4  32.7     1.7      M    M
  8500   -9.6  14.7   110    4    2   7.8   4.3    0.2  32.4     1.5      M    M
  8250   -9.1  15.6   100    5    2   6.9   3.8    0.0  32.1     1.3      M    M
  8000   -8.6  16.5   100    5    3   6.2   3.4   -0.2  31.6     1.0      M    M
  7750   -8.1  17.4   105    5    3   7.4   4.1   -0.5  31.2     0.8      M    M
  7500   -7.5  18.5   105    5    3   8.3   4.5   -0.6  30.9     0.6      M    M
  7250   -7.0  19.4   105    6    3   7.2   4.0   -0.7  30.7     0.5      M    M
  7000   -6.5  20.3   100    6    3   7.1   3.9   -1.0  30.3     0.3      M    M
  6750   -5.9  21.4   095    7    4   6.8   3.7   -1.2  29.9     0.0      M    M
  6500   -5.4  22.3   095    8    4   7.5   4.1   -1.4  29.5    -0.2     31  0.2
  6250   -4.8  23.4   090    7    4   8.3   4.5   -1.5  29.3    -0.3      6  0.0
  6000   -4.2  24.4   085    7    3   8.6   4.7   -1.6  29.1    -0.5      M    M
  5750   -3.6  25.5   080    6    3  10.1   5.5   -1.6  29.1    -0.5      M    M
  5500   -2.8  27.0   080    5    3  10.6   5.8   -1.5  29.2    -0.4      M    M

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

           01/21/2015 at 0800 MST          |       01/21/2015 at 1100 MST
                                           |
K index... +10.0  LI... +5.6               | K index... +12.0  LI... +5.7
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -1.2
                                           |
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 -55.4 -67.7  295  34 17   1.1   0.6 | -55.2 -67.4  295  31 16   1.3   0.7
 45000 -53.7 -64.7  290  41 21   1.1   0.6 | -53.1 -63.6  290  36 19   1.4   0.7
 40000 -53.9 -65.0  280  53 27  -0.4  -0.2 | -53.2 -63.8  280  47 24  -0.3  -0.2
 38000 -54.3 -65.7  275  59 30  -1.8  -1.0 | -53.4 -64.1  275  52 27  -1.9  -1.0
 36000 -55.4 -67.7  270  65 33  -1.9  -1.0 | -54.7 -66.5  270  56 29  -2.1  -1.2
 34000 -56.6 -69.9  265  71 36  -1.8  -1.0 | -55.9 -68.6  265  61 31  -2.0  -1.1
 32000 -55.5 -67.9  265  75 39   3.4   1.9 | -55.3 -67.5  260  67 35   2.6   1.4
 30000 -53.4 -64.1  260  80 41   3.4   1.9 | -53.7 -64.7  260  74 38   2.7   1.5
 29000 -51.6 -60.9  265  78 40   8.2   4.5 | -52.1 -61.8  260  74 38   8.0   4.4
 28000 -48.4 -55.1  265  73 38   8.4   4.6 | -49.1 -56.4  260  70 36   8.2   4.5
 27000 -45.9 -50.6  265  70 36   8.3   4.6 | -46.6 -51.9  260  67 34   8.1   4.5
 26000 -43.6 -46.5  270  65 33   6.7   3.7 | -44.3 -47.7  265  63 33   7.4   4.0
 25000 -41.6 -42.9  270  59 30   6.7   3.7 | -42.0 -43.6  265  60 31   7.4   4.1
 24000 -39.6 -39.3  275  53 27   6.8   3.7 | -39.8 -39.6  270  56 29   7.4   4.1
 23000 -37.4 -35.3  280  50 26   8.7   4.8 | -37.5 -35.5  270  53 27   8.0   4.4
 22000 -34.8 -30.6  280  50 26   8.6   4.7 | -35.2 -31.4  275  50 26   8.0   4.4
 21000 -32.2 -26.0  285  50 26   8.8   4.8 | -32.8 -27.0  280  47 24   8.1   4.4
 20000 -29.9 -21.8  285  48 24   7.0   3.9 | -30.7 -23.3  280  44 23   6.4   3.5
 19500 -28.9 -20.0  285  45 23   7.1   3.9 | -29.7 -21.5  275  42 21   6.4   3.5
 19000 -27.8 -18.0  280  43 22   7.1   3.9 | -28.8 -19.8  275  39 20   6.4   3.5
 18500 -26.8 -16.2  280  41 21   7.2   3.9 | -27.8 -18.0  275  37 19   6.5   3.5
 18000 -25.8 -14.4  280  39 20   6.4   3.5 | -26.9 -16.4  270  35 18   5.0   2.8
 17500 -24.8 -12.6  280  36 19   6.3   3.4 | -26.2 -15.2  270  32 17   4.8   2.6
 17000 -23.9 -11.0  280  34 17   6.2   3.4 | -25.5 -13.9  270  30 15   4.8   2.6
 16500 -23.0  -9.4  280  31 16   5.9   3.3 | -24.8 -12.6  270  27 14   4.8   2.6
 16000 -22.1  -7.8  275  28 15   5.9   3.3 | -24.1 -11.4  270  24 12   4.9   2.7
 15500 -21.4  -6.5  275  26 13   4.6   2.5 | -23.3  -9.9  270  21 11   6.1   3.4
 15000 -20.7  -5.3  270  23 12   4.7   2.6 | -22.4  -8.3  265  18  9   5.8   3.2
 14500 -20.0  -4.0  270  21 11   5.4   3.0 | -21.4  -6.5  260  15  8   8.0   4.4
 14000 -18.8  -1.8  265  17  9   5.5   3.0 | -19.7  -3.5  255  13  7   7.8   4.3
 13500 -18.0  -0.4  260  15  8   5.6   3.1 | -18.6  -1.5  250  12  6   7.6   4.2
 13000 -17.2   1.0  255  14  7   6.0   3.3 | -17.4   0.7  245  11  6   6.8   3.8
 12500 -16.1   3.0  250  13  7   7.4   4.1 | -16.7   1.9  245   9  5   4.4   2.4
 12000 -15.0   5.0  240  12  6   6.6   3.6 | -16.0   3.2  245   8  4   4.5   2.5
 11500 -14.3   6.3  235  10  5   4.1   2.2 | -15.3   4.5  245   6  3   4.6   2.5
 11000 -13.7   7.3  230   8  4   4.4   2.4 | -14.7   5.5  245   4  2   5.5   3.0
 10500 -13.0   8.6  220   6  3   4.9   2.7 | -13.7   7.3  280   2  1   6.9   3.8
 10250 -12.6   9.3  210   5  3   5.2   2.8 | -13.2   8.2  320   1  1   7.0   3.8
 10000 -12.3   9.9  200   4  2   2.9   1.6 | -12.7   9.1  355   2  1   3.7   2.1
  9750 -12.1  10.2  195   4  2   4.7   2.6 | -12.5   9.5  360   2  1   5.0   2.7
  9500 -11.6  11.1  195   3  1   8.1   4.5 | -11.9  10.6  015   2  1   8.5   4.7
  9250 -11.0  12.2  195   2  1   6.8   3.8 | -11.4  11.5  025   3  1   7.0   3.9
  9000 -10.6  12.9  175   1  1   5.4   3.0 | -10.9  12.4  035   3  2   5.6   3.0
  8750 -10.2  13.6  150   1  1   6.2   3.4 | -10.5  13.1  045   5  2   6.6   3.6
  8500  -9.6  14.7  120   2  1   7.9   4.3 |  -9.9  14.2  050   6  3   8.6   4.7
  8250  -9.1  15.6  100   2  1   7.0   3.8 |  -9.4  15.1  050   7  4   5.8   3.2
  8000  -8.6  16.5  095   3  1   6.1   3.3 |  -9.0  15.8  055   8  4   4.0   2.2
  7750  -8.1  17.4  090   3  2   7.6   4.2 |  -8.7  16.3  060   9  5   4.1   2.2
  7500  -7.5  18.5  085   4  2   7.7   4.2 |  -8.4  16.9  060  10  5   5.6   3.1
  7250  -7.1  19.2  080   5  3   5.2   2.9 |  -7.9  17.8  060  11  6   8.2   4.5
  7000  -6.7  19.9  075   6  3   4.6   2.5 |  -7.3  18.9  060  12  6   8.4   4.6
  6750  -6.4  20.5  075   8  4   5.1   2.8 |  -6.7  19.9  060  12  6   8.7   4.8
  6500  -6.0  21.2  075   9  4   7.7   4.2 |  -6.0  21.2  060  12  6   9.7   5.3
  6250  -5.3  22.5  070   8  4   9.1   5.0 |  -5.3  22.5  055  11  6  10.0   5.5
  6000  -4.7  23.5  065   8  4   9.5   5.2 |  -4.5  23.9  055  11  6   9.7   5.3
  5750  -3.9  25.0  065   7  4  11.1   6.1 |  -3.8  25.2  055  10  5  11.6   6.3
  5500  -3.1  26.4  060   7  3  10.9   6.0 |  -2.8  27.0  050   9  5  15.0   8.2

           01/21/2015 at 1400 MST          |       01/21/2015 at 1700 MST
                                           |
K index... +11.0  LI... +4.6               | K index... +9.5  LI... +4.3
CAPE... +20.0  CIN... -0.9                 | CAPE... +20.0  CIN... 0.0
                                           |
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 -55.1 -67.2  295  32 16   1.2   0.7 | -54.6 -66.3  300  30 15   1.4   0.7
 45000 -53.3 -63.9  290  37 19   1.2   0.7 | -52.6 -62.7  300  33 17   1.4   0.7
 40000 -52.6 -62.7  285  43 22   0.2   0.1 | -52.0 -61.6  290  36 18   0.1   0.1
 38000 -52.6 -62.7  280  45 23  -1.4  -0.7 | -52.0 -61.6  290  37 19  -0.5  -0.3
 36000 -53.6 -64.5  270  49 25  -1.6  -0.9 | -52.4 -62.3  280  38 20  -0.7  -0.4
 34000 -54.5 -66.1  265  54 28  -1.6  -0.9 | -52.9 -63.2  275  40 21  -0.7  -0.4
 32000 -54.0 -65.2  260  59 30   2.1   1.2 | -52.4 -62.3  265  47 24   1.6   0.9
 30000 -52.8 -63.0  255  63 33   2.2   1.2 | -51.4 -60.5  255  57 30   1.6   0.9
 29000 -51.5 -60.7  255  64 33   6.8   3.8 | -50.6 -59.1  250  61 31   5.4   3.0
 28000 -49.5 -57.1  255  64 33   6.8   3.8 | -48.6 -55.5  255  60 31   5.2   2.9
 27000 -46.9 -52.4  260  63 33   6.9   3.8 | -47.0 -52.6  255  60 31   5.2   2.9
 26000 -44.8 -48.6  260  62 32   7.3   4.0 | -45.4 -49.7  260  59 30   6.9   3.8
 25000 -42.6 -44.7  260  60 31   7.2   4.0 | -43.4 -46.1  260  57 29   6.7   3.7
 24000 -40.5 -40.9  260  57 29   7.2   4.0 | -41.4 -42.5  260  54 28   6.7   3.7
 23000 -38.2 -36.8  265  54 28   8.0   4.4 | -39.4 -38.9  265  51 26   5.7   3.1
 22000 -35.9 -32.6  265  51 26   7.9   4.4 | -37.7 -35.9  265  46 24   5.8   3.2
 21000 -33.5 -28.3  270  47 24   8.0   4.4 | -36.0 -32.8  265  42 21   5.9   3.2
 20000 -31.6 -24.9  270  43 22   5.2   2.9 | -34.0 -29.2  265  36 18   7.3   4.0
 19500 -30.8 -23.4  270  40 21   5.2   2.8 | -32.9 -27.2  265  32 17   7.3   4.0
 19000 -30.1 -22.2  270  37 19   5.2   2.9 | -31.8 -25.2  265  29 15   7.3   4.0
 18500 -29.3 -20.7  270  35 18   5.2   2.9 | -30.7 -23.3  265  25 13   7.3   4.0
 18000 -28.5 -19.3  270  32 16   5.6   3.1 | -29.6 -21.3  265  22 11   6.4   3.5
 17500 -27.7 -17.9  270  29 15   5.8   3.2 | -28.8 -19.8  270  20 11   5.9   3.2
 17000 -26.8 -16.2  265  25 13   5.8   3.2 | -27.9 -18.2  270  19 10   6.0   3.3
 16500 -26.0 -14.8  265  22 11   5.9   3.2 | -27.0 -16.6  270  17  9   6.8   3.7
 16000 -25.1 -13.2  260  18  9   5.8   3.2 | -25.9 -14.6  275  16  8   6.9   3.8
 15500 -24.2 -11.6  260  16  8   6.4   3.5 | -25.1 -13.2  275  15  8   5.2   2.9
 15000 -23.3  -9.9  250  14  7   6.2   3.4 | -24.3 -11.7  280  13  7   5.4   3.0
 14500 -22.3  -8.1  250  12  6   7.6   4.1 | -23.1  -9.6  295  11  6   5.4   3.0
 14000 -20.6  -5.1  250  11  6   6.9   3.8 | -22.3  -8.1  305  11  5   5.6   3.1
 13500 -19.8  -3.6  255  10  5   4.4   2.4 | -21.3  -6.3  320  10  5   6.6   3.6
 13000 -19.1  -2.4  260   9  5   5.0   2.7 | -20.4  -4.7  335  10  5   6.7   3.7
 12500 -18.2  -0.8  270   6  3   6.8   3.8 | -19.3  -2.7  350  10  5   7.3   4.0
 12000 -17.2   1.0  300   3  2   6.7   3.7 | -18.2  -0.8  005  11  6   7.3   4.0
 11500 -16.2   2.8  005   4  2   6.6   3.6 | -17.1   1.2  015  13  7   7.5   4.1
 11000 -15.3   4.5  035   7  3   6.8   3.7 | -16.0   3.2  020  15  8   7.6   4.2
 10500 -14.2   6.4  035   8  4   7.0   3.9 | -14.9   5.2  030  16  8   7.7   4.2
 10250 -13.7   7.3  035   9  4   7.3   4.0 | -14.3   6.3  030  16  8   7.8   4.3
 10000 -13.3   8.1  035   9  5   4.0   2.2 | -13.9   7.0  035  17  9   3.1   1.7
  9750 -13.0   8.6  035   9  5   5.4   3.5 | -13.7   7.3  035  17  9   5.7   3.1
  9500 -12.4   9.7  035  10  5   9.3   5.1 | -13.0   8.6  040  16  8  11.5   6.3
  9250 -11.8  10.8  035  10  5   7.6   4.2 | -12.2  10.0  045  16  8   8.7   4.8
  9000 -11.3  11.7  040  11  5   5.7   3.2 | -11.7  10.9  045  16  8   5.9   3.2
  8750 -10.9  12.4  045  11  6   6.2   3.4 | -11.3  11.7  050  15  8   7.0   3.8
  8500 -10.4  13.3  050  12  6   7.5   4.1 | -10.6  12.9  055  15  8   9.2   5.0
  8250  -9.9  14.2  050  13  7   6.6   3.6 | -10.0  14.0  055  15  8   7.3   4.0
  8000  -9.4  15.1  055  13  7   6.0   3.3 |  -9.5  14.9  055  14  7   5.9   3.2
  7750  -8.9  16.0  060  14  7   6.6   3.6 |  -9.1  15.6  060  14  7   7.3   4.0
  7500  -8.4  16.9  065  14  7   7.4   4.0 |  -8.5  16.7  060  14  7   7.8   4.3
  7250  -7.9  17.8  065  14  7   7.7   4.2 |  -8.0  17.6  065  12  6   7.0   3.8
  7000  -7.3  18.9  065  13  7   7.7   4.2 |  -7.5  18.5  065  11  6   6.9   3.8
  6750  -6.8  19.8  065  13  7   8.0   4.4 |  -7.0  19.4  065  10  5   7.4   4.1
  6500  -6.1  21.0  065  12  6   9.7   5.3 |  -6.4  20.5  065   9  4   8.8   4.8
  6250  -5.4  22.3  060  11  6  10.4   5.7 |  -5.7  21.7  065   8  4   9.0   5.0
  6000  -4.6  23.7  060  11  5  10.7   5.9 |  -5.0  23.0  060   7  3   9.9   5.4
  5750  -3.8  25.2  060  10  5  12.6   6.9 |  -4.3  24.3  055   6  3  11.2   6.1
  5500  -2.8  27.0  055   9  5  13.8   7.6 |  -3.5  25.7  055   5  3  10.4   5.7
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613


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