Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 141245
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0645 MDT Monday, April 14, 2014

This forecast is for Monday, April 14, 2014:

If the trigger temperature of 25.4 F/-3.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 600 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14141 ft MSL (8854 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 0745 MDT
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................. 12562 ft MSL (7275 ft AGL)
Thermal soaring outlook for Tuesday 04/15...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 16090 ft MSL (10803 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18300 ft MSL (13013 ft AGL)
Wave soaring outlook for Tuesday 04/15......... Poor

Remarks...

Sunrise/Sunset.................... 06:23:25 / 19:35:44 MDT
Total possible sunshine........... 13 hr 12 min 20 sec (792 min 20 sec)
Altitude of sun at 12:59:44 MDT... 59.82 degrees

Upper air data from numerical model forecast valid on 04/14/2014 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9458 ft MSL (4171 ft AGL)
Lifted condensation level....... 13087 ft MSL (7800 ft AGL)
Lifted index.................... +6.5
K index......................... +0.8

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  -54.2 -65.6   280   39   20   2.5   1.4      M     M       M      M    M
 45000  -50.5 -58.9   280   40   21   2.4   1.3      M     M       M      M    M
 40000  -48.3 -54.9   300   36   19   1.3   0.7      M     M       M      M    M
 38000  -47.6 -53.7   310   36   18   0.0   0.0      M     M       M      M    M
 36000  -47.6 -53.7   315   34   17   0.0   0.0      M     M       M      M    M
 34000  -47.6 -53.7   325   33   17   0.0   0.0      M     M       M      M    M
 32000  -47.8 -54.0   330   34   17  -0.4  -0.2      M     M       M      M    M
 30000  -48.0 -54.4   335   34   18  -0.3  -0.1      M     M       M      M    M
 29000  -47.6 -53.7   335   33   17   3.2   1.8   27.7  81.9    16.6      M    M
 28000  -46.6 -51.9   330   30   16   3.4   1.8   25.1  77.2    14.8      M    M
 27000  -45.3 -49.5   320   27   14   3.4   1.9   22.1  71.7    12.7      M    M
 26000  -43.9 -47.0   315   26   13   7.3   4.0   20.1  68.2    11.4      M    M
 25000  -41.8 -43.2   310   25   13   7.0   3.9   19.0  66.2    10.6      M    M
 24000  -39.7 -39.5   310   25   13   7.0   3.9   18.0  64.4    10.0      M    M
 23000  -37.6 -35.7   305   24   12   7.7   4.3   17.1  62.8     9.4      M    M
 22000  -35.3 -31.5   315   24   12   7.7   4.2   16.3  61.4     8.8      M    M
 21000  -33.0 -27.4   320   23   12   7.7   4.2   15.6  60.1     8.3      M    M
 20000  -30.8 -23.4   325   24   13   6.9   3.8   14.7  58.5     7.6      M    M
 19500  -29.8 -21.6   330   26   13   6.9   3.8   14.2  57.5     7.2      M    M
 19000  -28.8 -19.8   335   27   14   6.9   3.8   13.7  56.6     6.8      M    M
 18500  -27.8 -18.0   340   28   14   6.9   3.8   13.2  55.7     6.5      M    M
 18000  -26.8 -16.2   340   29   15   5.8   3.2   12.7  54.8     6.1      M    M
 17500  -26.0 -14.8   345   29   15   5.3   2.9   11.9  53.4     5.4      M    M
 17000  -25.2 -13.4   345   28   14   4.8   2.7   11.1  52.1     4.8      M    M
 16500  -24.7 -12.5   350   28   14   3.0   1.6   10.1  50.1     3.9      M    M
 16000  -24.2 -11.6   350   27   14   2.8   1.5    8.9  48.1     2.9      M    M
 15500  -23.6 -10.5   355   27   14   5.9   3.2    8.0  46.5     2.1      M    M
 15000  -22.8  -9.0   355   26   14   5.6   3.1    7.3  45.2     1.4      M    M
 14500  -22.0  -7.6   355   26   13   4.6   2.5    6.6  43.8     0.8      M    M
 14000  -21.0  -5.8   360   26   13   4.3   2.4    5.3  41.5    -0.4    581  3.0
 13500  -20.5  -4.9   360   25   13   3.2   1.7    4.3  39.7    -1.3    550  2.8
 13000  -20.0  -4.0   360   25   13   3.3   1.8    3.2  37.7    -2.3    521  2.6
 12500  -19.5  -3.1   360   24   12   3.4   1.9    2.2  35.9    -3.3    491  2.5
 12000  -19.0  -2.2   360   22   12   3.4   1.9    1.1  34.0    -4.3    461  2.3
 11500  -18.5  -1.3   355   20   11   3.5   1.9    0.1  32.2    -5.2    431  2.2
 11000  -17.9  -0.2   355   18    9   3.7   2.0   -0.9  30.4    -6.2    401  2.0
 10500  -17.3   0.9   355   17    9   4.1   2.2   -1.8  28.8    -7.1    368  1.9
 10250  -17.0   1.4   355   17    9   4.5   2.5   -2.2  28.0    -7.6    351  1.8
 10000  -16.7   1.9   355   16    8   2.2   1.2   -2.7  27.2    -8.0    335  1.7
  9750  -16.6   2.1   355   17    9   5.0   2.8   -3.3  26.1    -8.6    323  1.6
  9500  -16.0   3.2   355   17    9   9.4   5.2   -3.4  25.9    -8.7    297  1.5
  9250  -15.3   4.5   355   17    9   7.8   4.3   -3.5  25.7    -8.9    271  1.4
  9000  -14.8   5.4   360   17    9   6.4   3.5   -3.7  25.4    -9.1    248  1.3
  8750  -14.3   6.3   360   17    9   7.9   4.3   -3.9  24.9    -9.4    226  1.1
  8500  -13.6   7.5   360   17    9  10.4   5.7   -4.0  24.9    -9.4    197  1.0
  8250  -12.9   8.8   360   17    9   8.9   4.9   -3.9  24.9    -9.4    168  0.9
  8000  -12.3   9.9   360   17    9   7.8   4.3   -4.1  24.7    -9.6    143  0.7
  7750  -11.7  10.9   360   17    9   8.2   4.5   -4.2  24.4    -9.8    118  0.6
  7500  -11.1  12.0   360   17    9   8.4   4.6   -4.3  24.2    -9.9     92  0.5
  7250  -10.4  13.3   355   17    9   8.7   4.7   -4.4  24.1   -10.0     65  0.3
  7000   -9.8  14.4   355   16    8   8.7   4.8   -4.5  23.9   -10.1     39  0.2
  6750   -9.2  15.4   350   16    8   8.4   4.6   -4.6  23.8   -10.2     12  0.1
  6500   -8.6  16.5   345   15    8   6.4   3.5   -4.7  23.5   -10.4      M    M
  6250   -8.2  17.2   335   13    7   5.2   2.9   -5.1  22.9   -10.8      M    M
  6000   -7.8  18.0   325   12    6   5.9   3.2   -5.4  22.3   -11.2      M    M
  5750   -7.4  18.7   315   10    5   6.1   3.4   -5.6  21.8   -11.5      M    M
  5500   -6.9  19.6   305    7    4   5.7   3.1   -5.9  21.4   -11.8      M    M

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

           04/14/2014 at 0900 MDT          |       04/14/2014 at 1200 MDT
                                           |
K index... -17.3  LI... +9.6               | K index... -26.8  LI... +11.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -54.9 -66.8  285  36 19   2.2   1.2 | -55.3 -67.5  290  38 20   1.9   1.0
 45000 -51.5 -60.7  290  40 20   2.2   1.2 | -52.4 -62.3  310  45 23   1.9   1.1
 40000 -49.0 -56.2  300  39 20   1.7   0.9 | -51.4 -60.5  320  42 21   0.6   0.3
 38000 -48.3 -54.9  310  38 20  -1.8  -1.0 | -51.2 -60.2  330  42 22  -0.8  -0.5
 36000 -49.2 -56.6  325  40 21  -1.6  -0.9 | -51.7 -61.1  335  49 25  -0.8  -0.4
 34000 -50.3 -58.5  345  46 24  -1.9  -1.1 | -52.2 -62.0  340  56 29  -0.8  -0.5
 32000 -49.4 -56.9  350  50 26   1.8   1.0 | -50.9 -59.6  345  61 31   2.4   1.3
 30000 -48.3 -54.9  355  54 28   1.3   0.7 | -49.5 -57.1  350  64 33   3.5   1.9
 29000 -46.8 -52.2  360  56 29   6.1   3.3 | -47.5 -53.5  350  64 33   7.2   4.0
 28000 -45.0 -49.0  360  57 29   6.0   3.3 | -45.3 -49.5  350  63 32   7.2   4.0
 27000 -43.2 -45.8  005  58 30   6.0   3.3 | -43.1 -45.6  350  61 32   7.2   4.0
 26000 -41.4 -42.5  005  59 30   6.7   3.7 | -41.0 -41.8  355  60 31   7.0   3.9
 25000 -39.4 -38.9  005  58 30   6.6   3.6 | -38.9 -38.0  355  58 30   7.0   3.9
 24000 -37.4 -35.3  005  57 29   6.6   3.6 | -36.8 -34.2  355  56 29   7.0   3.9
 23000 -35.5 -31.9  005  54 28   5.2   2.9 | -34.6 -30.3  355  54 28   7.4   4.1
 22000 -33.9 -29.0  360  50 25   5.4   2.9 | -32.4 -26.3  355  53 27   7.4   4.1
 21000 -32.3 -26.1  355  45 23   5.4   2.9 | -30.2 -22.4  355  52 27   7.5   4.1
 20000 -30.8 -23.4  350  41 21   4.6   2.5 | -28.3 -18.9  355  50 26   6.0   3.3
 19500 -30.1 -22.2  350  39 20   4.6   2.5 | -27.4 -17.3  355  49 25   6.0   3.3
 19000 -29.4 -20.9  345  38 19   4.6   2.5 | -26.5 -15.7  355  48 25   6.0   3.3
 18500 -28.7 -19.7  345  36 19   4.6   2.5 | -25.5 -13.9  355  48 24   6.1   3.3
 18000 -28.0 -18.4  340  35 18   4.7   2.6 | -24.7 -12.5  355  47 24   4.5   2.4
 17500 -27.3 -17.1  345  34 17   4.7   2.6 | -24.1 -11.4  355  45 23   4.2   2.3
 17000 -26.6 -15.9  345  33 17   4.8   2.6 | -23.5 -10.3  355  44 23   4.0   2.2
 16500 -25.5 -13.9  345  32 16   5.3   2.9 | -22.6  -8.7  350  42 22   3.7   2.0
 16000 -24.7 -12.5  345  31 16   5.9   3.2 | -22.0  -7.6  350  41 21   4.4   2.4
 15500 -23.7 -10.7  345  30 16   6.4   3.5 | -21.3  -6.3  350  39 20   4.6   2.5
 15000 -22.7  -8.9  350  29 15   5.8   3.2 | -20.6  -5.1  345  37 19   4.5   2.5
 14500 -22.1  -7.8  350  28 14   4.1   2.3 | -20.0  -4.0  345  36 18   4.2   2.3
 14000 -21.4  -6.5  350  27 14   4.2   2.3 | -19.3  -2.7  345  35 18   3.8   2.1
 13500 -20.8  -5.4  350  25 13   4.4   2.4 | -18.9  -2.0  345  34 17   2.7   1.5
 13000 -20.1  -4.2  350  25 13   4.1   2.3 | -18.5  -1.3  340  33 17   2.8   1.6
 12500 -19.6  -3.3  350  24 12   3.2   1.7 | -18.1  -0.6  340  32 16   3.1   1.7
 12000 -19.2  -2.6  350  24 12   3.5   1.9 | -17.6   0.3  340  31 16   4.1   2.2
 11500 -18.5  -1.3  355  24 12   4.5   2.5 | -16.8   1.8  340  29 15   5.8   3.2
 11000 -17.9  -0.2  355  23 12   5.7   3.1 | -16.0   3.2  335  27 14   6.5   3.5
 10500 -16.8   1.8  355  23 12   7.2   4.0 | -14.9   5.2  335  24 12   7.1   3.9
 10250 -16.3   2.7  360  22 12   7.4   4.0 | -14.4   6.1  335  22 11   6.7   3.7
 10000 -15.8   3.6  360  22 11   5.3   2.9 | -14.0   6.8  335  21 11   3.1   1.7
  9750 -15.4   4.3  360  22 11   7.2   4.0 | -13.8   7.2  335  20 10   6.0   3.3
  9500 -14.7   5.5  360  20 10  10.7   5.9 | -13.0   8.6  335  18  9  10.9   6.0
  9250 -13.9   7.0  355  18 10   8.6   4.7 | -12.3   9.9  335  16  8   8.0   4.4
  9000 -13.4   7.9  355  18  9   6.5   3.6 | -11.9  10.6  340  15  8   5.3   2.9
  8750 -12.9   8.8  355  17  9   7.7   4.2 | -11.4  11.5  340  14  7   7.3   4.0
  8500 -12.2  10.0  355  16  8   9.3   5.1 | -10.8  12.6  340  12  6   9.3   5.1
  8250 -11.6  11.1  350  15  8   8.1   4.5 | -10.1  13.8  345  11  6   7.4   4.0
  8000 -11.0  12.2  350  14  7   7.1   3.9 |  -9.6  14.7  345  10  5   6.1   3.3
  7750 -10.4  13.3  350  14  7   8.3   4.6 |  -9.2  15.4  350  10  5   7.7   4.2
  7500  -9.8  14.4  350  13  7   8.5   4.7 |  -8.5  16.7  350   9  5   8.1   4.4
  7250  -9.2  15.4  345  12  6   7.6   4.2 |  -8.0  17.6  350   7  4   7.1   3.9
  7000  -8.6  16.5  345  12  6   7.7   4.2 |  -7.5  18.5  350   6  3   7.1   3.9
  6750  -8.1  17.4  345  11  6   8.0   4.4 |  -6.9  19.6  355   5  2   7.9   4.3
  6500  -7.5  18.5  340  10  5   7.6   4.2 |  -6.3  20.7  350   3  2   9.6   5.3
  6250  -7.0  19.4  330   8  4   6.6   3.6 |  -5.5  22.1  345   2  1   9.9   5.4
  6000  -6.5  20.3  310   6  3   7.7   4.2 |  -4.8  23.4  335   1  1  10.1   5.6
  5750  -5.8  21.6  295   5  2  10.7   5.9 |  -4.0  24.8  320   1  1  13.1   7.2
  5500  -5.0  23.0  275   4  2  13.3   7.3 |  -2.9  26.8  310   1  1  16.9   9.3

           04/14/2014 at 1500 MDT          |       04/14/2014 at 1800 MDT
                                           |
K index... -15.9  LI... +8.5               | K index... -7.6  LI... +7.7
CAPE... 0.0  CIN... M                      | 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 -55.3 -67.5  295  39 20   0.8   0.5 | -56.2 -69.2  305  38 20   0.6   0.3
 45000 -54.0 -65.2  310  49 25   0.9   0.5 | -55.3 -67.5  320  51 26   0.7   0.4
 40000 -53.5 -64.3  330  51 26   0.3   0.2 | -55.4 -67.7  340  57 30  -0.1  -0.1
 38000 -53.4 -64.1  335  55 28  -0.9  -0.5 | -55.5 -67.9  345  63 32  -0.6  -0.3
 36000 -54.0 -65.2  340  64 33  -0.9  -0.5 | -55.9 -68.6  350  75 38  -0.6  -0.3
 34000 -54.6 -66.3  345  75 39   1.2   0.6 | -56.3 -69.3  355  87 45   0.8   0.4
 32000 -51.5 -60.7  350  80 41   5.3   2.9 | -51.0 -59.8  355  88 45   8.3   4.5
 30000 -48.3 -54.9  355  86 44   6.2   3.4 | -46.1 -51.0  355  87 45   7.8   4.3
 29000 -46.3 -51.3  355  82 42   6.9   3.8 | -43.8 -46.8  355  85 44   7.6   4.2
 28000 -44.2 -47.6  355  77 40   6.9   3.8 | -41.5 -42.7  355  82 42   7.6   4.2
 27000 -42.1 -43.8  355  73 38   6.9   3.8 | -39.2 -38.6  355  80 41   7.8   4.3
 26000 -40.0 -40.0  350  70 36   7.5   4.1 | -37.2 -35.0  355  76 39   6.3   3.5
 25000 -37.7 -35.9  350  66 34   7.5   4.1 | -35.3 -31.5  355  71 37   6.3   3.5
 24000 -35.4 -31.7  350  63 33   7.5   4.1 | -33.4 -28.1  350  67 34   6.3   3.5
 23000 -33.3 -27.9  345  61 31   6.9   3.8 | -31.4 -24.5  350  63 32   6.8   3.8
 22000 -31.2 -24.2  345  58 30   6.9   3.8 | -29.3 -20.7  350  60 31   6.8   3.8
 21000 -29.2 -20.6  345  56 29   7.0   3.9 | -27.3 -17.1  345  57 29   6.8   3.7
 20000 -27.3 -17.1  340  54 28   6.1   3.3 | -25.4 -13.7  345  54 28   6.1   3.3
 19500 -26.4 -15.5  340  53 27   6.1   3.4 | -24.5 -12.1  345  53 27   6.1   3.3
 19000 -25.5 -13.9  340  52 27   6.1   3.4 | -23.6 -10.5  345  52 27   6.1   3.4
 18500 -24.6 -12.3  340  51 26   6.2   3.4 | -22.7  -8.9  340  50 26   6.2   3.4
 18000 -23.7 -10.7  340  50 26   5.6   3.1 | -21.9  -7.4  340  49 25   4.4   2.4
 17500 -22.8  -9.0  340  48 25   5.6   3.1 | -21.3  -6.3  340  47 24   4.6   2.5
 17000 -22.0  -7.6  340  47 24   5.7   3.1 | -20.6  -5.1  340  46 24   4.7   2.6
 16500 -20.7  -5.3  340  44 22   5.8   3.2 | -19.9  -3.8  340  45 23   4.7   2.6
 16000 -19.8  -3.6  340  42 22   4.7   2.6 | -18.8  -1.8  340  43 22   4.7   2.6
 15500 -19.1  -2.4  340  40 21   4.5   2.5 | -18.1  -0.6  335  42 22   4.7   2.6
 15000 -18.5  -1.3  335  38 20   4.2   2.3 | -17.4   0.7  335  42 21   5.1   2.8
 14500 -17.9  -0.2  335  37 19   4.1   2.2 | -16.6   2.1  330  40 21   5.2   2.9
 14000 -17.2   1.0  335  35 18   4.2   2.3 | -15.8   3.6  330  39 20   5.8   3.2
 13500 -16.6   2.1  335  35 18   4.4   2.4 | -14.9   5.2  325  37 19   6.2   3.4
 13000 -16.0   3.2  330  34 17   4.6   2.5 | -14.0   6.8  320  35 18   6.6   3.6
 12500 -15.3   4.5  325  32 16   5.1   2.8 | -12.9   8.8  315  32 17   7.1   3.9
 12000 -14.5   5.9  325  30 15   5.8   3.2 | -11.9  10.6  310  29 15   7.5   4.1
 11500 -13.6   7.5  320  27 14   6.6   3.6 | -10.7  12.7  305  27 14   7.8   4.3
 11000 -12.6   9.3  320  23 12   6.5   3.6 |  -9.5  14.9  305  25 13   6.7   3.7
 10500 -11.6  11.1  325  21 11   6.6   3.6 |  -8.7  16.3  305  23 12   6.1   3.4
 10250 -11.2  11.8  325  20 10   5.8   3.2 |  -8.2  17.2  300  22 11   5.1   2.8
 10000 -10.8  12.6  325  19 10   2.8   1.5 |  -8.0  17.6  300  21 11   2.7   1.5
  9750 -10.6  12.9  330  18  9   4.9   2.7 |  -7.8  18.0  300  20 10   3.9   2.2
  9500 -10.1  13.8  330  17  9   8.2   4.5 |  -7.4  18.7  300  18  9   6.0   3.3
  9250  -9.5  14.9  335  16  8   6.3   3.5 |  -6.9  19.6  300  15  8   4.5   2.5
  9000  -9.1  15.6  335  15  7   4.7   2.6 |  -6.7  19.9  300  13  7   3.1   1.7
  8750  -8.7  16.3  335  13  7   5.4   3.0 |  -6.4  20.5  305  12  6   3.5   1.9
  8500  -8.3  17.1  340  12  6   6.2   3.4 |  -6.2  20.8  305  10  5   3.9   2.1
  8250  -7.9  17.8  340  10  5   5.0   2.8 |  -5.9  21.4  305   8  4   3.3   1.8
  8000  -7.5  18.5  340   8  4   4.8   2.6 |  -5.7  21.7  300   6  3   3.0   1.7
  7750  -7.2  19.0  340   7  3   3.9   2.2 |  -5.5  22.1  295   4  2   2.8   1.5
  7500  -6.9  19.6  340   5  2   5.7   3.1 |  -5.2  22.6  270   2  1   5.3   2.9
  7250  -6.3  20.7  340   3  1   8.5   4.7 |  -4.7  23.5  230   2  1   8.2   4.5
  7000  -5.7  21.7  330   1  0   7.7   4.2 |  -4.1  24.6  205   3  2   8.0   4.4
  6750  -5.1  22.8  170   1  1   9.4   5.2 |  -3.5  25.7  190   4  2   8.9   4.9
  6500  -4.3  24.3  170   2  1  10.6   5.8 |  -2.8  27.0  185   5  2  10.1   5.5
  6250  -3.6  25.5  170   2  1   9.8   5.4 |  -2.0  28.4  185   5  2   9.6   5.3
  6000  -2.8  27.0  170   2  1  10.2   5.6 |  -1.3  29.7  180   5  2  10.7   5.9
  5750  -2.0  28.4  165   2  1  13.8   7.6 |  -0.4  31.3  175   5  2  12.8   7.0
  5500  -0.8  30.6  170   2  1  19.2  10.5 |   0.5  32.9  170   4  2  13.1   7.2
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613



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