Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240123
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1923 MDT Thursday, March 23, 2017

This forecast is for Friday, March 24, 2017:

If the trigger temperature of 48.8 F/9.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8706 ft MSL (3399 ft AGL)

Forecast maximum temperature................... 46.0 F/8.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 7533 ft MSL (2227 ft AGL)
Thermal soaring outlook for Saturday 03/25..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14893 ft MSL (9586 ft AGL)
Wave soaring outlook for Saturday 03/25........ Poor

Remarks...

Sunrise/Sunset.................... 06:55:54 / 19:14:53 MDT
Total possible sunshine........... 12 hr 18 min 59 sec (738 min 59 sec)
Altitude of sun at 13:05:34 MDT... 51.96 degrees

Upper air data from numerical model forecast valid on 03/24/2017 at 0600 MDT

Freezing level.................. 6494 ft MSL (1187 ft AGL)
Convective condensation level... 11191 ft MSL (5884 ft AGL)
Lifted condensation level....... 9151 ft MSL (3845 ft AGL)
Lifted index.................... +6.6
K index......................... +21.2

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  -55.7 -68.3   235   40   20   3.6   2.0      M     M       M      M    M
 45000  -50.1 -58.2   240   31   16   1.2   0.7      M     M       M      M    M
 40000  -49.4 -56.9   250   21   11   0.5   0.3      M     M       M      M    M
 38000  -50.3 -58.5   255   11    6  -4.5  -2.5      M     M       M      M    M
 36000  -53.0 -63.4   075    8    4  -4.5  -2.5      M     M       M      M    M
 34000  -55.7 -68.3   075   28   14   0.8   0.4      M     M       M      M    M
 32000  -51.3 -60.3   065   33   17   7.4   4.1      M     M       M      M    M
 30000  -46.2 -51.2   060   38   19   9.0   5.0   29.4  84.8    16.2      M    M
 29000  -43.5 -46.3   055   37   19   8.9   4.9   28.9  84.0    16.1      M    M
 28000  -40.8 -41.4   050   37   19   8.9   4.9   28.6  83.5    16.0      M    M
 27000  -38.2 -36.8   045   38   19   8.9   4.9   28.4  83.2    16.1      M    M
 26000  -35.7 -32.3   045   37   19   8.1   4.4   27.8  82.0    15.7      M    M
 25000  -33.3 -27.9   040   37   19   8.1   4.4   27.1  80.8    15.4      M    M
 24000  -30.9 -23.6   035   36   19   8.1   4.5   26.6  79.8    15.1      M    M
 23000  -28.6 -19.5   030   36   19   7.8   4.3   25.8  78.5    14.7      M    M
 22000  -26.3 -15.3   025   36   19   7.8   4.3   25.1  77.1    14.2      M    M
 21000  -24.0 -11.2   025   36   19   7.7   4.2   24.4  76.0    13.8      M    M
 20000  -21.8  -7.2   020   37   19   7.3   4.0   23.5  74.4    13.2      M    M
 19500  -20.7  -5.3   020   37   19   7.3   4.0   23.1  73.6    12.9      M    M
 19000  -19.6  -3.3   015   37   19   7.3   4.0   22.7  72.8    12.6      M    M
 18500  -18.5  -1.3   015   37   19   7.4   4.1   22.3  72.2    12.3      M    M
 18000  -17.5   0.5   015   37   19   6.7   3.7   21.8  71.3    12.0      M    M
 17500  -16.5   2.3   015   37   19   6.7   3.7   21.3  70.4    11.6      M    M
 17000  -15.5   4.1   010   37   19   7.2   4.0   20.8  69.5    11.2      M    M
 16500  -14.4   6.1   010   38   19   7.4   4.1   20.4  68.8    10.9      M    M
 16000  -13.3   8.1   010   38   20   6.9   3.8   20.1  68.1    10.6      M    M
 15500  -12.3   9.9   010   40   20   4.3   2.4   18.8  65.8     9.5      M    M
 15000  -11.7  10.9   010   40   21   4.2   2.3   17.9  64.2     8.7      M    M
 14500  -11.0  12.2   010   41   21   4.2   2.3   16.9  62.5     7.9      M    M
 14000  -10.4  13.3   015   41   21   5.1   2.8   16.0  60.8     7.1      M    M
 13500   -9.4  15.1   015   41   21   8.0   4.4   15.6  60.0     6.7      M    M
 13000   -8.3  17.1   015   42   22   7.8   4.3   15.3  59.5     6.4      M    M
 12500   -7.2  19.0   015   43   22   7.3   4.0   14.9  58.8     6.1      M    M
 12000   -6.1  21.0   015   43   22   7.3   4.0   14.5  58.1     5.7      M    M
 11500   -5.2  22.6   015   44   23   6.3   3.4   14.0  57.3     5.2      M    M
 11000   -4.3  24.3   020   46   24   6.1   3.4   13.5  56.3     4.7      M    M
 10500   -3.6  25.5   020   47   24   3.0   1.7   12.6  54.7     3.9      M    M
 10250   -3.4  25.9   020   47   24   3.1   1.7   12.1  53.8     3.4      M    M
 10000   -3.2  26.2   015   47   24   3.8   2.1   11.6  52.9     2.9      M    M
  9750   -2.9  26.8   020   48   25   2.8   1.6   11.1  52.0     2.5      M    M
  9500   -2.8  27.0   020   48   25   1.4   0.8   10.5  50.9     1.9      M    M
  9250   -2.6  27.3   020   49   25   1.7   0.9    9.9  49.8     1.3      M    M
  9000   -2.5  27.5   020   49   25   2.1   1.1    9.2  48.6     0.7      M    M
  8750   -2.4  27.7   020   50   25   0.9   0.5    8.6  47.5     0.1      M    M
  8500   -2.4  27.7   015   50   26  -0.5  -0.3    7.9  46.2    -0.6    246  1.3
  8250   -2.4  27.7   015   51   26  -0.2  -0.1    7.1  44.8    -1.4    239  1.2
  8000   -2.4  27.7   010   51   26   1.7   0.9    6.4  43.5    -2.0    231  1.2
  7750   -2.1  28.2   005   50   26   3.8   2.1    5.9  42.5    -2.6    217  1.1
  7500   -1.9  28.6   005   48   25   3.3   1.8    5.4  41.7    -3.0    201  1.0
  7250   -1.6  29.1   360   47   24   4.9   2.7    4.9  40.9    -3.5    186  0.9
  7000   -1.1  30.0   355   44   23   8.0   4.4    4.7  40.4    -3.7    164  0.8
  6750   -0.5  31.1   355   42   22   7.0   3.8    4.6  40.2    -3.9    139  0.7
  6500   -0.1  31.8   355   40   20   6.2   3.4    4.3  39.7    -4.2    118  0.6
  6250    0.5  32.9   355   37   19   9.4   5.2    4.1  39.4    -4.4     94  0.5
  6000    1.3  34.3   355   34   18  11.6   6.4    4.2  39.6    -4.3     63  0.3
  5750    2.1  35.8   355   32   16   9.5   5.2    4.3  39.7    -4.2     31  0.2
  5500    2.7  36.9   350   28   14   8.0   4.4    4.2  39.5    -4.4      5  0.0

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

           03/24/2017 at 0900 MDT          |       03/24/2017 at 1200 MDT
                                           |
K index... +15.3  LI... +5.2               | K index... +3.0  LI... +8.0
CAPE... +0.8  CIN... 0.0                   | CAPE... +11.4  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 -56.1 -69.0  240  31 16   3.1   1.7 | -56.6 -69.9  250  27 14   3.0   1.6
 45000 -51.4 -60.5  250  28 15   2.7   1.5 | -52.2 -62.0  265  27 14   2.3   1.3
 40000 -50.8 -59.4  290  22 11   0.3   0.2 | -52.1 -61.8  305  20 10  -0.0  -0.0
 38000 -51.2 -60.2  305  20 10  -2.1  -1.2 | -52.8 -63.0  325  23 12  -2.7  -1.5
 36000 -52.5 -62.5  320  12  6  -2.1  -1.2 | -54.4 -65.9  335  30 15  -2.7  -1.5
 34000 -53.6 -64.5  360   8  4   2.4   1.3 | -55.5 -67.9  340  35 18   6.6   3.6
 32000 -50.7 -59.3  050  16  8   5.0   2.7 | -51.1 -60.0  350  18  9   7.4   4.0
 30000 -47.5 -53.5  060  27 14   8.5   4.7 | -46.5 -51.7  040   5  3   9.8   5.4
 29000 -44.1 -47.4  045  25 13   9.2   5.0 | -43.0 -45.4  010   9  4   9.5   5.2
 28000 -41.4 -42.5  030  26 13   9.2   5.0 | -40.1 -40.2  360  12  6   9.5   5.2
 27000 -38.6 -37.5  015  27 14   8.7   4.8 | -37.3 -35.1  350  16  8   8.8   4.8
 26000 -36.4 -33.5  005  30 15   7.3   4.0 | -34.8 -30.6  345  20 10   8.1   4.4
 25000 -34.2 -29.6  355  34 17   7.4   4.0 | -32.4 -26.3  340  25 13   8.1   4.4
 24000 -32.0 -25.6  350  38 20   7.3   4.0 | -30.0 -22.0  335  31 16   7.8   4.3
 23000 -29.3 -20.7  350  39 20   9.4   5.1 | -28.0 -18.4  345  33 17   6.5   3.6
 22000 -26.5 -15.7  355  39 20   9.3   5.1 | -26.0 -14.8  360  36 18   6.5   3.6
 21000 -23.7 -10.7  360  39 20   8.6   4.7 | -24.1 -11.4  005  40 20   7.9   4.3
 20000 -21.4  -6.5  360  38 19   7.6   4.2 | -21.5  -6.7  005  39 20   8.8   4.8
 19500 -20.3  -4.5  005  37 19   7.7   4.2 | -20.1  -4.2  005  39 20   8.8   4.8
 19000 -19.1  -2.4  005  37 19   7.7   4.2 | -18.8  -1.8  005  38 20   8.8   4.8
 18500 -18.0  -0.4  005  36 18   7.6   4.2 | -17.5   0.5  005  38 20   8.4   4.6
 18000 -16.9   1.6  005  36 18   7.3   4.0 | -16.4   2.5  005  37 19   7.7   4.2
 17500 -15.8   3.6  005  35 18   7.4   4.1 | -15.2   4.6  005  35 18   7.9   4.4
 17000 -14.8   5.4  005  35 18   5.3   2.9 | -14.2   6.4  005  34 17   5.6   3.1
 16500 -14.1   6.6  005  34 17   4.9   2.7 | -13.4   7.9  005  32 17   5.7   3.1
 16000 -13.4   7.9  005  32 17   4.0   2.2 | -12.5   9.5  005  31 16   5.4   2.9
 15500 -13.1   8.4  010  32 17   2.6   1.4 | -11.4  11.5  010  30 15   5.3   2.9
 15000 -12.5   9.5  010  32 17   4.1   2.2 | -10.8  12.6  010  30 15   3.3   1.8
 14500 -11.9  10.6  010  33 17   4.7   2.6 | -10.3  13.5  010  31 16   3.1   1.7
 14000 -11.2  11.8  010  33 17   5.3   2.9 |  -9.9  14.2  010  33 17   2.4   1.3
 13500 -10.4  13.3  010  34 18   6.0   3.3 |  -9.7  14.5  010  35 18   2.1   1.1
 13000  -9.5  14.9  005  35 18   5.9   3.3 |  -9.4  15.1  010  37 19   3.1   1.7
 12500  -8.6  16.5  360  37 19   5.7   3.1 |  -8.8  16.2  010  38 19   3.8   2.1
 12000  -7.8  18.0  360  39 20   5.1   2.8 |  -8.2  17.2  010  39 20   1.9   1.0
 11500  -7.2  19.0  005  41 21   3.5   1.9 |  -8.3  17.1  010  40 21  -0.2  -0.1
 11000  -6.7  19.9  005  42 22   3.5   1.9 |  -8.3  17.1  015  41 21   2.0   1.1
 10500  -6.2  20.8  010  42 22   3.3   1.8 |  -7.8  18.0  010  39 20   4.4   2.4
 10250  -6.0  21.2  010  42 22   3.8   2.1 |  -7.5  18.5  010  37 19   2.8   1.6
 10000  -5.7  21.7  015  42 22   2.1   1.1 |  -7.3  18.9  005  37 19   4.5   2.4
  9750  -5.6  21.9  015  43 22   1.8   1.0 |  -6.8  19.8  005  36 18   9.4   5.1
  9500  -5.4  22.3  015  44 23   3.2   1.8 |  -6.0  21.2  360  34 18  10.3   5.7
  9250  -5.2  22.6  015  45 23   2.9   1.6 |  -5.3  22.5  360  33 17   9.2   5.0
  9000  -5.0  23.0  015  46 23   3.8   2.1 |  -4.7  23.5  360  32 17   8.2   4.5
  8750  -4.6  23.7  015  46 23   4.7   2.6 |  -4.0  24.8  360  32 17  10.0   5.5
  8500  -4.3  24.3  010  45 23   4.6   2.5 |  -3.2  26.2  360  32 16  11.2   6.1
  8250  -3.9  25.0  005  45 23   5.5   3.0 |  -2.4  27.7  355  32 16  10.6   5.8
  8000  -3.5  25.7  005  43 22   6.9   3.8 |  -1.6  29.1  355  31 16  10.6   5.8
  7750  -2.9  26.8  360  42 21   7.8   4.3 |  -0.9  30.4  355  31 16   9.8   5.4
  7500  -2.3  27.9  360  40 21   8.6   4.7 |  -0.2  31.6  355  31 16   9.5   5.2
  7250  -1.7  28.9  360  39 20   9.3   5.1 |   0.6  33.1  355  31 16  10.3   5.6
  7000  -0.9  30.4  355  38 20  10.2   5.6 |   1.4  34.5  355  30 16  10.7   5.9
  6750  -0.2  31.6  355  37 19   9.1   5.0 |   2.2  36.0  355  30 15   9.8   5.4
  6500   0.5  32.9  355  36 18   9.2   5.0 |   2.9  37.2  355  29 15  10.4   5.7
  6250   1.2  34.2  355  33 17  10.2   5.6 |   3.7  38.7  355  28 15  11.9   6.5
  6000   1.9  35.4  355  31 16  10.2   5.6 |   4.6  40.3  355  27 14  10.8   5.9
  5750   2.7  36.9  355  29 15  10.1   5.5 |   5.4  41.7  355  26 13  13.5   7.4
  5500   3.4  38.1  355  25 13   9.9   5.4 |   6.7  44.1  355  24 12  21.5  11.8

           03/24/2017 at 1500 MDT          |       03/24/2017 at 1800 MDT
                                           |
K index... +8.3  LI... +6.2                | K index... -0.3  LI... +5.6
CAPE... +1.0  CIN... -0.2                  | CAPE... 0.0  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 -56.9 -70.4  245  23 12   2.6   1.4 | -58.4 -73.1  255  26 14   2.3   1.3
 45000 -53.0 -63.4  255  19 10   1.7   0.9 | -54.9 -66.8  260  25 13  -0.2  -0.1
 40000 -55.3 -67.5  320  38 19  -1.6  -0.9 | -59.6 -75.3  315  54 28  -3.1  -1.7
 38000 -55.6 -68.1  335  45 23   0.6   0.3 | -59.5 -75.1  325  60 31   3.8   2.1
 36000 -55.3 -67.5  355  53 27   0.6   0.3 | -57.0 -70.6  340  56 29   3.8   2.1
 34000 -54.4 -65.9  010  61 31   8.5   4.7 | -54.0 -65.2  355  56 29   8.3   4.6
 32000 -49.8 -57.6  360  45 23   7.6   4.2 | -48.9 -56.0  360  57 29   8.5   4.7
 30000 -45.2 -49.4  350  32 17   8.6   4.7 | -43.8 -46.8  005  58 30   8.5   4.7
 29000 -42.0 -43.6  345  29 15   8.5   4.7 | -41.2 -42.2  360  56 29   8.5   4.7
 28000 -39.5 -39.1  340  27 14   8.5   4.7 | -38.7 -37.7  355  56 29   8.5   4.7
 27000 -37.0 -34.6  335  25 13   7.1   3.9 | -36.1 -33.0  350  55 28   8.3   4.6
 26000 -35.1 -31.2  340  28 15   6.3   3.5 | -33.7 -28.7  350  56 29   8.2   4.5
 25000 -33.2 -27.8  340  32 16   6.3   3.5 | -31.2 -24.2  345  58 30   8.2   4.5
 24000 -31.3 -24.3  345  35 18   6.8   3.7 | -28.7 -19.7  340  59 30   8.0   4.4
 23000 -29.0 -20.2  345  36 18   7.8   4.3 | -26.4 -15.5  340  58 30   7.6   4.2
 22000 -26.6 -15.9  350  36 18   7.8   4.3 | -24.1 -11.4  340  56 29   7.6   4.2
 21000 -24.3 -11.7  350  36 19   8.7   4.7 | -21.9  -7.4  340  54 28   6.6   3.6
 20000 -21.6  -6.9  350  37 19   8.9   4.9 | -20.0  -4.0  340  50 26   6.3   3.5
 19500 -20.3  -4.5  350  37 19   8.9   4.9 | -19.1  -2.4  345  48 25   6.3   3.5
 19000 -19.0  -2.2  350  38 19   8.8   4.8 | -18.1  -0.6  345  46 24   6.3   3.4
 18500 -17.6   0.3  350  38 20   7.7   4.2 | -17.2   1.0  345  43 22   6.2   3.4
 18000 -16.7   1.9  350  38 19   6.7   3.7 | -15.8   3.6  345  39 20   6.0   3.3
 17500 -15.7   3.7  355  38 19   6.7   3.7 | -14.9   5.2  340  36 19   6.3   3.5
 17000 -14.6   5.7  355  37 19   8.3   4.5 | -13.9   7.0  340  34 17   6.6   3.6
 16500 -13.4   7.9  355  37 19   8.3   4.5 | -13.0   8.6  340  32 16   6.6   3.6
 16000 -12.3   9.9  360  37 19   5.2   2.8 | -12.1  10.2  340  30 16   6.1   3.3
 15500 -11.7  10.9  360  37 19   4.4   2.4 | -11.2  11.8  345  30 15   6.4   3.5
 15000 -10.8  12.6  360  37 19   4.0   2.2 | -10.4  13.3  345  29 15   4.1   2.3
 14500 -10.2  13.6  005  37 19   4.1   2.3 |  -9.8  14.4  345  28 15   4.3   2.3
 14000  -9.7  14.5  010  37 19   2.3   1.3 |  -9.2  15.4  350  27 14   4.2   2.3
 13500  -9.4  15.1  010  36 19   1.9   1.1 |  -8.6  16.5  350  26 14   4.2   2.3
 13000  -9.0  15.8  010  36 18   3.6   2.0 |  -7.9  17.8  350  26 13   5.2   2.8
 12500  -8.3  17.1  015  35 18   4.3   2.3 |  -7.1  19.2  350  25 13   5.5   3.0
 12000  -7.7  18.1  015  35 18   3.8   2.1 |  -6.3  20.7  350  24 12   5.4   2.9
 11500  -7.2  19.0  015  31 16   3.6   2.0 |  -5.5  22.1  350  22 11   5.3   2.9
 11000  -6.7  19.9  010  28 14   6.5   3.5 |  -4.8  23.4  355  20 10   5.5   3.0
 10500  -5.6  21.9  010  24 12   8.7   4.8 |  -4.0  24.8  360  16  8   6.6   3.6
 10250  -5.1  22.8  005  23 12   3.3   1.8 |  -3.7  25.3  005  14  7   1.8   1.0
 10000  -5.0  23.0  005  22 11   6.0   3.3 |  -3.6  25.5  005  13  7   5.0   2.8
  9750  -4.1  24.6  005  22 11  13.5   7.4 |  -2.8  27.0  010  13  7  12.3   6.8
  9500  -3.2  26.2  005  21 11  12.4   6.8 |  -2.0  28.4  010  12  6  11.0   6.0
  9250  -2.3  27.9  005  21 11  10.2   5.6 |  -1.2  29.8  010  12  6   9.9   5.4
  9000  -1.7  28.9  005  21 11   7.9   4.3 |  -0.6  30.9  015  12  6   8.6   4.7
  8750  -1.0  30.2  005  21 11  10.4   5.7 |   0.1  32.2  015  11  6  10.1   5.6
  8500  -0.2  31.6  005  21 11  11.1   6.1 |   0.9  33.6  015  11  6  10.6   5.8
  8250   0.6  33.1  005  21 11  10.5   5.8 |   1.7  35.1  015  11  6  10.2   5.6
  8000   1.4  34.5  005  21 11  10.3   5.6 |   2.5  36.5  015  11  6  10.0   5.5
  7750   2.1  35.8  005  20 11   9.8   5.4 |   3.2  37.8  015  11  6   9.7   5.3
  7500   2.8  37.0  005  20 10   9.6   5.3 |   3.9  39.0  015  11  6   9.7   5.3
  7250   3.6  38.5  005  20 10  10.1   5.6 |   4.7  40.5  015  11  6  10.1   5.6
  7000   4.3  39.7  005  20 10  10.2   5.6 |   5.4  41.7  015  11  5  10.3   5.6
  6750   5.1  41.2  005  20 10  10.0   5.5 |   6.2  43.2  015  10  5   9.7   5.3
  6500   5.9  42.6  005  19 10  10.8   5.9 |   6.9  44.4  015  10  5   9.9   5.5
  6250   6.7  44.1  005  19 10  12.0   6.6 |   7.7  45.9  015  10  5  10.7   5.9
  6000   7.6  45.7  005  18  9  10.5   5.8 |   8.5  47.3  015  10  5  10.2   5.6
  5750   8.4  47.1  005  18  9  13.9   7.6 |   9.3  48.7  015   9  5  11.2   6.1
  5500   9.8  49.6  005  17  9  24.5  13.5 |  10.2  50.4  015   9  4  14.1   7.7
________________________________________________________________________________

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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