Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 140144
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1944 MDT Sunday, April 13, 2014

This forecast is for Monday, April 14, 2014:

If the trigger temperature of 25.2 F/-3.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 456 ft/min (2.3 m/s)
   Maximum height of thermals.................. 14630 ft MSL (9343 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 0800 MDT
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................. 13048 ft MSL (7761 ft AGL)
Thermal soaring outlook for Tuesday 04/15...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13390 ft MSL (8103 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 20510 ft MSL (15223 ft AGL)
Wave soaring outlook for Tuesday 04/15......... Poor

Remarks... None

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... 8667 ft MSL (3380 ft AGL)
Lifted condensation level....... 12662 ft MSL (7375 ft AGL)
Lifted index.................... +6.9
K index......................... +0.1

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  -55.2 -67.4   270   35   18   2.2   1.2      M     M       M      M    M
 45000  -52.0 -61.6   270   34   17   2.2   1.2      M     M       M      M    M
 40000  -47.5 -53.5   295   38   20   2.9   1.6      M     M       M      M    M
 38000  -46.3 -51.3   305   40   21  -0.3  -0.2      M     M       M      M    M
 36000  -46.5 -51.7   315   37   19  -0.4  -0.2      M     M       M      M    M
 34000  -46.7 -52.1   325   35   18  -0.4  -0.2      M     M       M      M    M
 32000  -46.9 -52.4   325   34   17  -0.4  -0.2      M     M       M      M    M
 30000  -47.1 -52.8   330   33   17  -0.3  -0.1      M     M       M      M    M
 29000  -46.8 -52.2   325   31   16   2.5   1.4   28.8  83.9    17.5      M    M
 28000  -46.0 -50.8   320   29   15   2.6   1.4   25.9  78.6    15.4      M    M
 27000  -45.0 -49.0   310   27   14   2.6   1.4   22.5  72.4    13.0      M    M
 26000  -43.8 -46.8   305   27   14   8.2   4.5   20.4  68.7    11.6      M    M
 25000  -41.5 -42.7   300   26   14   7.7   4.2   19.6  67.2    11.1      M    M
 24000  -39.2 -38.6   300   26   13   7.7   4.2   18.8  65.9    10.6      M    M
 23000  -37.0 -34.6   300   26   13   6.5   3.6   18.0  64.4    10.1      M    M
 22000  -35.0 -31.0   305   26   14   6.7   3.7   16.8  62.3     9.2      M    M
 21000  -33.0 -27.4   310   27   14   6.7   3.7   15.8  60.4     8.4      M    M
 20000  -31.1 -24.0   315   27   14   6.1   3.3   14.5  58.2     7.5      M    M
 19500  -30.2 -22.4   320   27   14   6.1   3.3   13.9  57.0     7.0      M    M
 19000  -29.3 -20.7   320   26   14   6.1   3.3   13.2  55.8     6.4      M    M
 18500  -28.4 -19.1   325   26   14   6.1   3.3   12.6  54.7     6.0      M    M
 18000  -27.5 -17.5   330   27   14   5.3   2.9   12.0  53.6     5.5      M    M
 17500  -26.8 -16.2   330   26   13   4.7   2.6   11.1  52.0     4.7      M    M
 17000  -26.1 -15.0   335   26   13   4.6   2.5   10.3  50.5     4.0      M    M
 16500  -25.5 -13.9   340   25   13   3.8   2.1    9.3  48.7     3.2      M    M
 16000  -24.9 -12.8   340   24   12   3.8   2.1    8.3  46.9     2.3      M    M
 15500  -24.3 -11.7   340   23   12   4.9   2.7    7.4  45.3     1.5      M    M
 15000  -23.6 -10.5   340   21   11   4.9   2.7    6.5  43.8     0.8      M    M
 14500  -22.9  -9.2   340   20   10   4.1   2.2    5.7  42.2    -0.0    656  3.3
 14000  -22.0  -7.6   340   19   10   3.9   2.1    4.2  39.6    -1.3    607  3.1
 13500  -21.5  -6.7   340   18    9   3.1   1.7    3.2  37.7    -2.3    577  2.9
 13000  -21.0  -5.8   345   18    9   3.3   1.8    2.1  35.8    -3.3    548  2.8
 12500  -20.4  -4.7   345   17    9   4.2   2.3    1.1  34.1    -4.2    516  2.6
 12000  -19.8  -3.6   350   18    9   4.1   2.2    0.2  32.4    -5.1    483  2.5
 11500  -19.3  -2.7   355   18    9   3.7   2.0   -0.7  30.7    -6.0    452  2.3
 11000  -18.7  -1.7   355   18    9   4.6   2.5   -1.7  29.0    -7.0    420  2.1
 10500  -17.8  -0.0   360   18    9   6.3   3.5   -2.3  27.9    -7.6    379  1.9
 10250  -17.3   0.9   360   18    9   6.8   3.8   -2.5  27.4    -7.8    357  1.8
 10000  -16.9   1.6   360   18    9   3.0   1.7   -2.8  26.9    -8.2    337  1.7
  9750  -16.8   1.8   360   18    9   4.8   2.6   -3.4  25.8    -8.7    325  1.6
  9500  -16.1   3.0   005   19   10  10.2   5.6   -3.5  25.7    -8.9    298  1.5
  9250  -15.4   4.3   005   19   10   7.8   4.3   -3.6  25.6    -8.9    271  1.4
  9000  -15.0   5.0   005   20   10   4.9   2.7   -3.8  25.1    -9.2    249  1.3
  8750  -14.6   5.7   010   20   10   5.9   3.2   -4.2  24.4    -9.6    231  1.2
  8500  -14.1   6.6   010   20   10   8.6   4.7   -4.4  24.1    -9.8    207  1.1
  8250  -13.5   7.7   010   20   10   7.2   4.0   -4.5  23.9   -10.0    182  0.9
  8000  -13.0   8.6   005   20   10   6.1   3.4   -4.8  23.4   -10.3    160  0.8
  7750  -12.5   9.5   005   19   10   6.4   3.5   -5.0  23.0   -10.6    139  0.7
  7500  -12.0  10.4   360   19   10   7.0   3.8   -5.3  22.5   -10.8    117  0.6
  7250  -11.5  11.3   355   18    9   7.6   4.2   -5.5  22.2   -11.1     93  0.5
  7000  -10.9  12.4   350   16    8   7.4   4.0   -5.6  21.9   -11.3     69  0.4
  6750  -10.4  13.3   345   15    8   8.2   4.5   -5.8  21.6   -11.5     46  0.2
  6500   -9.7  14.5   340   14    7   9.3   5.1   -5.9  21.5   -11.6     19  0.1
  6250   -9.1  15.6   340   13    7   9.4   5.2   -5.9  21.4   -11.7      M    M
  6000   -8.4  16.9   335   12    6   9.3   5.1   -5.9  21.4   -11.7      M    M
  5750   -7.6  18.3   330   11    5  11.2   6.2   -5.9  21.4   -11.8      M    M
  5500   -6.7  19.9   330    9    5  14.8   8.1   -5.6  21.9   -11.5      M    M

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

           04/14/2014 at 0900 MDT          |       04/14/2014 at 1200 MDT
                                           |
K index... -9.9  LI... +9.4                | K index... -20.6  LI... +10.6
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -4.1
                                           |
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 -55.0 -67.0  280  34 18   1.7   0.9 | -55.2 -67.4  290  34 18   1.9   1.0
 45000 -52.4 -62.3  280  38 20   1.7   0.9 | -52.3 -62.1  305  39 20   1.9   1.1
 40000 -49.9 -57.8  305  41 21   1.7   0.9 | -52.0 -61.6  315  43 22   0.1   0.0
 38000 -49.2 -56.6  315  43 22  -1.2  -0.7 | -51.9 -61.4  320  45 23   0.4   0.2
 36000 -49.8 -57.6  330  43 22  -1.0  -0.5 | -51.7 -61.1  330  48 25   0.4   0.2
 34000 -50.4 -58.7  345  46 23  -0.9  -0.5 | -51.4 -60.5  335  51 26   0.4   0.2
 32000 -49.0 -56.2  350  50 26   2.9   1.6 | -50.0 -58.0  345  54 28   2.5   1.4
 30000 -47.2 -53.0  355  54 28   2.7   1.5 | -48.5 -55.3  345  56 29   3.2   1.7
 29000 -45.8 -50.4  355  54 28   5.6   3.0 | -46.7 -52.1  350  55 28   6.3   3.5
 28000 -44.1 -47.4  360  54 28   5.5   3.0 | -44.8 -48.6  350  55 28   6.3   3.5
 27000 -42.4 -44.3  360  55 28   5.5   3.0 | -42.9 -45.2  350  54 28   6.3   3.5
 26000 -40.7 -41.3  005  54 28   6.2   3.4 | -41.1 -42.0  350  53 27   5.9   3.3
 25000 -38.9 -38.0  360  52 27   6.1   3.4 | -39.3 -38.7  355  52 27   5.9   3.3
 24000 -37.0 -34.6  360  50 26   6.2   3.4 | -37.5 -35.5  355  50 26   6.0   3.3
 23000 -35.3 -31.5  360  47 24   4.0   2.2 | -35.4 -31.7  355  49 25   8.5   4.6
 22000 -34.1 -29.4  355  43 22   4.2   2.3 | -32.9 -27.2  355  49 25   8.4   4.6
 21000 -32.8 -27.0  350  39 20   4.2   2.3 | -30.4 -22.7  355  48 25   8.6   4.7
 20000 -31.4 -24.5  345  37 19   5.0   2.7 | -28.5 -19.3  355  46 24   5.0   2.8
 19500 -30.7 -23.3  345  36 18   5.0   2.7 | -27.8 -18.0  355  45 23   5.0   2.7
 19000 -29.9 -21.8  340  35 18   5.0   2.8 | -27.0 -16.6  355  45 23   5.0   2.7
 18500 -29.2 -20.6  340  34 17   5.0   2.8 | -26.3 -15.3  355  44 22   5.0   2.8
 18000 -28.4 -19.1  340  33 17   5.5   3.0 | -25.6 -14.1  355  43 22   4.3   2.4
 17500 -27.5 -17.5  340  33 17   5.8   3.2 | -24.9 -12.8  350  41 21   4.2   2.3
 17000 -26.7 -16.1  340  32 17   5.8   3.2 | -24.3 -11.7  350  40 21   4.1   2.2
 16500 -25.8 -14.4  340  32 16   5.3   2.9 | -23.7 -10.7  350  39 20   3.9   2.1
 16000 -24.7 -12.5  340  31 16   5.1   2.8 | -22.8  -9.0  345  38 19   4.2   2.3
 15500 -23.9 -11.0  340  29 15   4.9   2.7 | -22.2  -8.0  345  37 19   4.4   2.4
 15000 -23.2  -9.8  340  28 15   4.4   2.4 | -21.5  -6.7  345  35 18   3.9   2.1
 14500 -22.7  -8.9  335  27 14   3.2   1.7 | -21.0  -5.8  345  35 18   3.2   1.7
 14000 -22.2  -8.0  335  25 13   3.3   1.8 | -20.6  -5.1  340  34 17   3.3   1.8
 13500 -21.7  -7.1  335  24 12   3.7   2.0 | -20.1  -4.2  340  33 17   3.5   1.9
 13000 -21.1  -6.0  340  23 12   3.8   2.1 | -19.5  -3.1  340  32 17   3.8   2.1
 12500 -20.5  -4.9  340  24 12   4.5   2.5 | -18.9  -2.0  340  32 16   4.5   2.5
 12000 -19.8  -3.6  345  24 12   4.5   2.5 | -18.3  -0.9  335  31 16   5.1   2.8
 11500 -19.1  -2.4  345  25 13   4.9   2.7 | -17.4   0.7  335  29 15   6.1   3.3
 11000 -18.4  -1.1  350  27 14   6.1   3.3 | -16.5   2.3  330  26 14   6.5   3.6
 10500 -17.3   0.9  350  25 13   7.7   4.2 | -15.5   4.1  330  24 12   7.0   3.9
 10250 -16.7   1.9  350  25 13   7.8   4.3 | -15.0   5.0  330  23 12   6.8   3.7
 10000 -16.2   2.8  350  24 12   5.8   3.2 | -14.6   5.7  330  22 11   3.4   1.9
  9750 -15.8   3.6  350  23 12   6.1   3.3 | -14.3   6.3  330  21 11   6.3   3.4
  9500 -15.3   4.5  350  22 11   7.8   4.3 | -13.6   7.5  330  20 10  11.2   6.1
  9250 -14.7   5.5  355  20 10   7.3   4.0 | -12.9   8.8  335  18  9   8.0   4.4
  9000 -14.2   6.4  355  19 10   7.0   3.8 | -12.4   9.7  335  17  9   5.0   2.8
  8750 -13.7   7.3  355  18  9   7.7   4.2 | -12.0  10.4  335  15  8   6.7   3.7
  8500 -13.1   8.4  355  17  9   8.7   4.8 | -11.4  11.5  335  12  6   8.5   4.7
  8250 -12.4   9.7  355  16  8   8.4   4.6 | -10.8  12.6  340  10  5   7.6   4.2
  8000 -11.8  10.8  355  15  8   7.7   4.2 | -10.3  13.5  340   8  4   6.9   3.8
  7750 -11.2  11.8  350  15  8   9.2   5.1 |  -9.8  14.4  340   7  4   8.3   4.5
  7500 -10.5  13.1  350  14  7   8.9   4.9 |  -9.1  15.6  340   6  3   9.5   5.2
  7250 -10.0  14.0  345  12  6   7.1   3.9 |  -8.4  16.9  340   6  3   9.1   5.0
  7000  -9.4  15.1  340  11  6   7.5   4.1 |  -7.7  18.1  340   5  3   8.9   4.9
  6750  -8.9  16.0  335   9  5   7.3   4.0 |  -7.0  19.4  345   5  3   9.9   5.4
  6500  -8.3  17.1  325   8  4   8.6   4.7 |  -6.2  20.8  340   5  3  10.7   5.9
  6250  -7.6  18.3  320   7  4   9.8   5.4 |  -5.5  22.1  340   5  2  10.4   5.7
  6000  -6.9  19.6  315   6  3   9.3   5.1 |  -4.7  23.5  340   4  2  10.0   5.5
  5750  -6.1  21.0  310   6  3  12.2   6.7 |  -3.8  25.2  340   4  2  14.4   7.9
  5500  -5.0  23.0  310   6  3  17.6   9.7 |  -2.4  27.7  340   4  2  23.1  12.7

           04/14/2014 at 1500 MDT          |       04/14/2014 at 1800 MDT
                                           |
K index... -16.0  LI... +8.5               | K index... -10.2  LI... +7.9
CAPE... 0.0  CIN... -3.4                   | CAPE... 0.0  CIN... -0.5
                                           |
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  290  36 18   1.4   0.8 | -56.0 -68.8  295  40 21   0.7   0.4
 45000 -53.0 -63.4  310  44 23   1.4   0.8 | -54.9 -66.8  320  52 27   0.7   0.4
 40000 -52.6 -62.7  325  46 24   0.2   0.1 | -54.6 -66.3  335  61 31   0.2   0.1
 38000 -52.5 -62.5  330  49 25  -0.3  -0.2 | -54.7 -66.5  340  67 34  -1.0  -0.6
 36000 -52.7 -62.9  340  58 30  -0.3  -0.2 | -55.3 -67.5  345  75 39  -1.1  -0.6
 34000 -52.9 -63.2  345  68 35  -0.6  -0.3 | -55.9 -68.6  350  85 44  -1.0  -0.5
 32000 -50.7 -59.3  350  76 39   3.9   2.1 | -51.5 -60.7  355  87 45   7.3   4.0
 30000 -48.4 -55.1  355  82 42   4.9   2.7 | -47.1 -52.8  355  88 45   7.7   4.3
 29000 -46.5 -51.7  355  79 41   6.4   3.5 | -44.8 -48.6  355  86 44   7.7   4.2
 28000 -44.6 -48.3  355  75 39   6.4   3.5 | -42.5 -44.5  355  84 43   7.7   4.2
 27000 -42.7 -44.9  355  71 37   6.4   3.5 | -40.2 -40.4  355  82 42   7.8   4.3
 26000 -40.6 -41.1  355  68 35   7.2   3.9 | -38.0 -36.4  355  79 41   6.9   3.8
 25000 -38.5 -37.3  350  65 34   7.2   3.9 | -35.9 -32.6  350  75 39   6.9   3.8
 24000 -36.3 -33.3  350  62 32   7.2   3.9 | -33.9 -29.0  350  71 37   7.0   3.8
 23000 -34.2 -29.6  350  59 31   6.7   3.7 | -31.9 -25.4  350  68 35   6.4   3.5
 22000 -32.2 -26.0  350  56 29   6.7   3.7 | -30.0 -22.0  350  64 33   6.3   3.5
 21000 -30.2 -22.4  350  53 27   6.7   3.7 | -28.1 -18.6  350  61 31   6.3   3.5
 20000 -28.3 -18.9  345  51 26   6.6   3.6 | -26.3 -15.3  345  58 30   6.0   3.3
 19500 -27.3 -17.1  345  49 25   6.6   3.6 | -25.4 -13.7  345  56 29   6.0   3.3
 19000 -26.3 -15.3  345  48 25   6.6   3.6 | -24.5 -12.1  345  55 28   6.0   3.3
 18500 -25.3 -13.5  345  47 24   6.7   3.7 | -23.6 -10.5  345  53 27   6.1   3.3
 18000 -24.4 -11.9  345  46 24   5.8   3.2 | -22.8  -9.0  345  51 26   5.2   2.9
 17500 -23.5 -10.3  345  45 23   5.8   3.2 | -22.0  -7.6  345  49 25   5.3   2.9
 17000 -22.6  -8.7  345  44 23   5.5   3.0 | -21.2  -6.2  345  47 24   4.9   2.7
 16500 -21.8  -7.2  345  43 22   5.3   2.9 | -20.5  -4.9  340  45 23   4.7   2.6
 16000 -20.7  -5.3  345  42 22   4.9   2.7 | -19.8  -3.6  340  43 22   4.6   2.5
 15500 -19.9  -3.8  345  41 21   4.8   2.6 | -18.8  -1.8  340  40 21   4.4   2.4
 15000 -19.2  -2.6  340  40 20   4.1   2.2 | -18.1  -0.6  340  39 20   4.7   2.6
 14500 -18.7  -1.7  340  39 20   3.6   2.0 | -17.4   0.7  335  38 19   4.9   2.7
 14000 -18.2  -0.8  340  38 19   3.6   2.0 | -16.6   2.1  335  36 19   5.4   3.0
 13500 -17.6   0.3  340  37 19   3.8   2.1 | -15.8   3.6  330  35 18   5.9   3.3
 13000 -17.1   1.2  335  36 19   4.5   2.5 | -14.9   5.2  330  34 17   6.3   3.5
 12500 -16.3   2.7  335  34 18   6.1   3.3 | -13.9   7.0  325  31 16   6.8   3.7
 12000 -15.4   4.3  330  32 17   6.4   3.5 | -12.9   8.8  320  28 14   6.8   3.7
 11500 -14.4   6.1  330  29 15   6.9   3.8 | -11.9  10.6  315  24 12   6.8   3.7
 11000 -13.4   7.9  330  25 13   6.6   3.6 | -10.9  12.4  315  20 11   6.0   3.3
 10500 -12.4   9.7  330  22 11   6.5   3.5 | -10.1  13.8  315  18  9   5.7   3.1
 10250 -12.0  10.4  330  20 10   5.7   3.1 |  -9.7  14.5  315  17  9   4.7   2.6
 10000 -11.6  11.1  330  19 10   2.6   1.4 |  -9.4  15.1  315  16  8   2.9   1.6
  9750 -11.4  11.5  330  18  9   5.1   2.8 |  -9.2  15.4  320  15  8   5.1   2.8
  9500 -10.9  12.4  330  16  8   9.0   4.9 |  -8.7  16.3  320  13  7   7.5   4.1
  9250 -10.3  13.5  330  13  7   6.3   3.4 |  -8.2  17.2  325  11  6   5.3   2.9
  9000  -9.9  14.2  335  11  6   3.2   1.8 |  -7.9  17.8  325   9  5   3.0   1.6
  8750  -9.7  14.5  340   9  5   5.3   2.9 |  -7.7  18.1  325   7  4   4.1   2.3
  8500  -9.2  15.4  340   7  4   7.5   4.1 |  -7.3  18.9  330   5  3   5.2   2.9
  8250  -8.6  16.5  350   6  3   7.7   4.2 |  -6.9  19.6  335   3  1   6.6   3.6
  8000  -8.0  17.6  350   5  3   7.9   4.3 |  -6.4  20.5  335   2  1   7.2   4.0
  7750  -7.4  18.7  350   5  3   9.1   5.0 |  -5.8  21.6  345   1  1   8.6   4.7
  7500  -6.7  19.9  350   5  2  10.4   5.7 |  -5.1  22.8  355   1  0  10.3   5.7
  7250  -5.9  21.4  350   5  2  10.0   5.5 |  -4.3  24.3  360   1  0   9.9   5.4
  7000  -5.2  22.6  350   5  2  10.0   5.5 |  -3.6  25.5  360   1  0  10.1   5.5
  6750  -4.4  24.1  350   4  2  10.3   5.7 |  -2.8  27.0  005   1  0   9.9   5.4
  6500  -3.6  25.5  350   4  2  10.6   5.8 |  -2.1  28.2  005   1  0   9.9   5.4
  6250  -2.8  27.0  350   4  2  10.6   5.8 |  -1.3  29.7  360   1  0  10.1   5.5
  6000  -2.0  28.4  350   4  2  10.3   5.6 |  -0.6  30.9  350   1  0  10.0   5.5
  5750  -1.2  29.8  350   4  2  15.1   8.3 |   0.2  32.4  000   0  0  12.9   7.1
  5500   0.3  32.5  350   4  2  24.1  13.2 |   1.4  34.5  350   1  0  17.8   9.8
________________________________________________________________________________

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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