Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260127
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1926 MDT Wednesday, March 25, 2015

This forecast is for Thursday, March 26, 2015:

If the trigger temperature of 48.1 F/8.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 736 ft/min (3.7 m/s)
   Maximum height of thermals.................. 15255 ft MSL (9948 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12616 ft MSL (7309 ft AGL)
Thermal soaring outlook for Friday 03/27....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 33854 ft MSL (28547 ft AGL)
Wave soaring outlook for Friday 03/27.......... Good

Remarks...

Sunrise/Sunset.................... 06:53:31 / 19:16:23 MDT
Total possible sunshine........... 12 hr 22 min 52 sec (742 min 52 sec)
Altitude of sun at 13:05:07 MDT... 52.55 degrees

Upper air data from numerical model forecast valid on 03/26/2015 at 0600 MDT

Freezing level.................. 7800 ft MSL (2493 ft AGL)
Convective condensation level... 13487 ft MSL (8180 ft AGL)
Lifted condensation level....... 14606 ft MSL (9299 ft AGL)
Lifted index.................... +2.2
K index......................... +7.2

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  -56.8 -70.2   340   40   21   1.5   0.8      M     M       M      M    M
 45000  -54.4 -65.9   350   52   27   1.1   0.6      M     M       M      M    M
 40000  -54.1 -65.4   345   58   30   0.2   0.1      M     M       M      M    M
 38000  -53.9 -65.0   345   60   31   0.3   0.2      M     M       M      M    M
 36000  -53.7 -64.7   350   63   32   0.3   0.2      M     M       M      M    M
 34000  -53.5 -64.3   355   66   34   3.0   1.6      M     M       M      M    M
 32000  -50.0 -58.0   355   68   35   5.2   2.8      M     M       M      M    M
 30000  -46.8 -52.2   355   69   36   6.2   3.4   29.4  84.9    11.2      M    M
 29000  -45.0 -49.0   355   69   35   6.1   3.3   27.8  82.1    10.1      M    M
 28000  -43.2 -45.8   355   68   35   6.1   3.3   26.4  79.5     9.2      M    M
 27000  -41.3 -42.3   355   67   35   6.4   3.5   25.1  77.2     8.3      M    M
 26000  -39.0 -38.2   355   66   34   8.0   4.4   24.3  75.7     7.7      M    M
 25000  -36.6 -33.9   355   65   33   8.0   4.4   23.6  74.5     7.3      M    M
 24000  -34.2 -29.6   355   63   33   8.0   4.4   23.1  73.5     6.9      M    M
 23000  -31.9 -25.4   350   60   31   7.6   4.2   22.2  72.0     6.3      M    M
 22000  -29.6 -21.3   350   57   30   7.6   4.2   21.4  70.6     5.7      M    M
 21000  -27.4 -17.3   345   54   28   8.0   4.4   20.8  69.4     5.2      M    M
 20000  -24.9 -12.8   345   53   27   8.3   4.6   20.2  68.3     4.8      M    M
 19500  -23.6 -10.5   340   52   27   8.3   4.6   19.9  67.9     4.6      M    M
 19000  -22.4  -8.3   340   51   26   8.3   4.6   19.7  67.5     4.4      M    M
 18500  -21.2  -6.2   340   51   26   8.0   4.4   19.5  67.1     4.3      M    M
 18000  -20.0  -4.0   335   49   25   7.5   4.1   19.1  66.4     3.9      M    M
 17500  -18.9  -2.0   335   47   24   7.9   4.3   18.7  65.7     3.6      M    M
 17000  -18.1  -0.6   330   43   22   3.7   2.0   18.0  64.5     3.0      M    M
 16500  -17.2   1.0   325   37   19   4.2   2.3   16.6  61.9     1.8      M    M
 16000  -16.5   2.3   325   35   18   4.7   2.6   15.7  60.3     1.0      M    M
 15500  -15.8   3.6   325   32   17   4.7   2.6   14.9  58.8     0.2      M    M
 15000  -15.1   4.8   330   30   16   4.7   2.6   14.0  57.3    -0.6    810  4.1
 14500  -14.4   6.1   330   29   15   4.5   2.5   13.2  55.7    -1.3    775  3.9
 14000  -13.6   7.5   335   27   14   6.6   3.6   12.5  54.4    -2.0    736  3.7
 13500  -12.6   9.3   335   27   14   6.8   3.7   12.0  53.6    -2.5    691  3.5
 13000  -11.5  11.3   340   27   14   8.1   4.5   11.6  52.8    -2.9    644  3.3
 12500  -10.2  13.6   340   27   14   8.5   4.6   11.4  52.4    -3.1    591  3.0
 12000   -9.0  15.8   340   26   14   7.9   4.4   11.1  52.0    -3.3    539  2.7
 11500   -7.8  18.0   340   25   13   7.8   4.3   10.8  51.5    -3.6    490  2.5
 11000   -6.7  19.9   340   25   13   8.1   4.4   10.5  50.9    -3.9    440  2.2
 10500   -5.5  22.1   335   25   13   8.8   4.8   10.2  50.4    -4.2    389  2.0
 10250   -4.9  23.2   335   25   13   5.1   2.8   10.1  50.2    -4.4    364  1.8
 10000   -4.7  23.5   335   25   13   4.0   2.2    9.6  49.3    -4.9    350  1.8
  9750   -4.2  24.4   330   25   13   8.6   4.7    9.4  48.9    -5.1    327  1.7
  9500   -3.5  25.7   330   25   13   9.8   5.4    9.3  48.8    -5.2    300  1.5
  9250   -2.8  27.0   325   25   13   7.0   3.8    9.3  48.7    -5.3    272  1.4
  9000   -2.4  27.7   325   25   13   4.9   2.7    8.9  48.0    -5.6    253  1.3
  8750   -2.0  28.4   325   25   13   7.2   3.9    8.6  47.5    -6.0    233  1.2
  8500   -1.4  29.5   320   25   13   7.7   4.3    8.5  47.2    -6.1    208  1.1
  8250   -0.9  30.4   320   25   13   6.7   3.7    8.3  46.9    -6.3    185  0.9
  8000   -0.4  31.3   315   25   13   6.4   3.5    8.0  46.4    -6.6    163  0.8
  7750    0.1  32.2   315   25   13   6.9   3.8    7.8  46.0    -6.9    142  0.7
  7500    0.6  33.1   310   24   13   7.3   4.0    7.6  45.6    -7.1    119  0.6
  7250    1.1  34.0   310   23   12   7.3   4.0    7.4  45.3    -7.3     95  0.5
  7000    1.7  35.1   310   22   11   7.2   4.0    7.2  45.0    -7.5     72  0.4
  6750    2.2  36.0   310   21   11   7.5   4.1    7.0  44.6    -7.8     48  0.2
  6500    2.8  37.0   305   20   10   7.2   3.9    6.8  44.3    -7.9     24  0.1
  6250    3.3  37.9   305   18    9   8.4   4.6    6.7  44.0    -8.1      M    M
  6000    3.9  39.0   300   16    8   3.2   1.8    6.5  43.7    -8.3      M    M
  5750    3.5  38.3   290   13    7 -13.1  -7.2    5.4  41.7    -9.5      M    M
  5500    1.9  35.4   275    8    4 -23.7 -13.0    3.2  37.8   -11.8     19  0.1

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

           03/26/2015 at 0900 MDT          |       03/26/2015 at 1200 MDT
                                           |
K index... +6.5  LI... +278.8              | K index... +8.7  LI... +277.8
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.6
                                           |
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  350  48 25   1.3   0.7 | -56.3 -69.3  350  46 24   1.2   0.7
 45000 -54.1 -65.4  350  63 32   1.1   0.6 | -54.4 -65.9  355  65 33   1.1   0.6
 40000 -53.0 -63.4  350  63 32   0.7   0.4 | -53.3 -63.9  355  73 37   0.7   0.4
 38000 -53.2 -63.8  350  67 34  -1.8  -1.0 | -53.8 -64.8  360  77 40  -2.7  -1.5
 36000 -54.2 -65.6  355  76 39  -1.8  -1.0 | -55.4 -67.7  360  84 43  -2.7  -1.5
 34000 -54.8 -66.6  360  87 45   6.6   3.6 | -56.5 -69.7  360  89 46   6.8   3.7
 32000 -51.4 -60.5  010  93 48   5.7   3.1 | -52.5 -62.5  005  87 45   6.5   3.6
 30000 -47.7 -53.9  015  99 51   8.5   4.6 | -48.4 -55.1  010  86 44   9.4   5.1
 29000 -45.2 -49.4  010  97 50   8.3   4.6 | -45.7 -50.3  010  89 46   9.1   5.0
 28000 -42.7 -44.9  005  96 49   8.3   4.6 | -42.3 -44.1  010  93 48   9.1   5.0
 27000 -40.2 -40.4  005  94 49   8.1   4.4 | -39.5 -39.1  010  95 49   8.9   4.9
 26000 -37.9 -36.2  360  90 46   7.5   4.1 | -36.9 -34.4  005  92 47   8.9   4.9
 25000 -35.7 -32.3  360  85 44   7.5   4.1 | -34.2 -29.6  005  88 45   8.9   4.9
 24000 -33.4 -28.1  360  80 41   7.5   4.1 | -31.6 -24.9  360  85 44   8.1   4.5
 23000 -31.2 -24.2  360  73 37   7.2   3.9 | -29.4 -20.9  360  76 39   7.3   4.0
 22000 -29.1 -20.4  360  65 33   7.2   4.0 | -27.2 -17.0  355  68 35   7.3   4.0
 21000 -26.9 -16.4  355  57 29   7.9   4.3 | -25.1 -13.2  350  60 31   6.3   3.5
 20000 -24.4 -11.9  350  54 28   8.3   4.6 | -23.2  -9.8  345  54 28   6.3   3.5
 19500 -23.2  -9.8  350  52 27   8.3   4.6 | -22.3  -8.1  345  51 26   6.3   3.5
 19000 -21.9  -7.4  345  51 26   8.3   4.6 | -21.3  -6.3  345  48 24   6.2   3.4
 18500 -20.7  -5.3  345  49 25   8.0   4.4 | -20.4  -4.7  345  45 23   7.7   4.2
 18000 -19.5  -3.1  345  50 26   7.6   4.2 | -19.1  -2.4  340  43 22   8.0   4.4
 17500 -17.9  -0.2  340  51 26   7.4   4.0 | -17.9  -0.2  340  42 21   7.7   4.2
 17000 -16.8   1.8  340  48 25   7.1   3.9 | -16.9   1.6  340  41 21   6.4   3.5
 16500 -15.7   3.7  340  45 23   6.6   3.6 | -16.0   3.2  340  40 21   6.7   3.7
 16000 -15.0   5.0  340  42 22   4.0   2.2 | -15.2   4.6  340  40 20   4.8   2.6
 15500 -14.4   6.1  340  39 20   4.1   2.2 | -14.4   6.1  345  39 20   4.9   2.7
 15000 -13.8   7.2  340  36 19   4.6   2.5 | -13.3   8.1  345  37 19   5.8   3.2
 14500 -13.1   8.4  340  34 17   4.3   2.4 | -12.5   9.5  340  33 17   5.7   3.1
 14000 -12.3   9.9  340  32 16   6.9   3.8 | -11.6  11.1  340  31 16   6.3   3.5
 13500 -11.2  11.8  340  30 16   7.0   3.8 | -10.6  12.9  345  31 16   6.1   3.3
 13000 -10.2  13.6  340  29 15   6.8   3.7 |  -9.6  14.7  345  32 16   8.0   4.4
 12500  -9.2  15.4  345  28 14   6.7   3.7 |  -8.4  16.9  345  32 17   7.9   4.4
 12000  -8.2  17.2  345  27 14   7.7   4.2 |  -7.3  18.9  345  33 17   7.7   4.2
 11500  -7.0  19.4  350  26 13   7.8   4.3 |  -6.1  21.0  345  32 17   7.8   4.3
 11000  -5.8  21.6  350  25 13   7.7   4.2 |  -5.1  22.8  345  31 16   6.4   3.5
 10500  -4.7  23.5  350  24 12   8.4   4.6 |  -4.1  24.6  345  28 14   7.1   3.9
 10250  -4.1  24.6  345  23 12   4.8   2.7 |  -3.7  25.3  345  27 14   3.0   1.6
 10000  -3.9  25.0  345  23 12   4.6   2.5 |  -3.5  25.7  345  26 13   4.4   2.4
  9750  -3.3  26.1  345  22 11  10.3   5.6 |  -2.9  26.8  340  23 12  10.8   5.9
  9500  -2.4  27.7  340  22 11  11.6   6.4 |  -2.1  28.2  340  21 11   9.9   5.4
  9250  -1.7  28.9  335  22 11   7.5   4.1 |  -1.5  29.3  335  19 10   7.2   4.0
  9000  -1.3  29.7  330  23 12   4.1   2.2 |  -1.0  30.2  330  18  9   5.9   3.2
  8750  -0.9  30.4  330  23 12   5.9   3.2 |  -0.5  31.1  320  18  9   7.9   4.3
  8500  -0.5  31.1  325  25 13   5.0   2.7 |   0.1  32.2  315  19 10   7.0   3.9
  8250  -0.3  31.5  320  25 13   2.1   1.2 |   0.5  32.9  310  18  9   4.9   2.7
  8000  -0.2  31.6  310  25 13   1.0   0.6 |   0.8  33.4  305  16  8   4.8   2.6
  7750  -0.1  31.8  305  25 13   1.9   1.1 |   1.2  34.2  300  15  8   5.0   2.8
  7500   0.1  32.2  300  24 12   5.6   3.1 |   1.6  34.9  295  13  7   7.2   4.0
  7250   0.7  33.3  300  22 11   7.8   4.3 |   2.2  36.0  295  12  6   8.8   4.8
  7000   1.2  34.2  295  20 11   7.1   3.9 |   2.8  37.0  295  11  6   8.0   4.4
  6750   1.8  35.2  295  19 10   7.6   4.2 |   3.4  38.1  295  10  5   9.9   5.4
  6500   2.3  36.1  290  17  9   7.0   3.8 |   4.2  39.6  295  10  5  10.8   5.9
  6250   2.8  37.0  285  15  8   7.2   4.0 |   5.0  41.0  290  10  5   9.8   5.4
  6000   3.3  37.9  280  14  7   4.7   2.6 |   5.7  42.3  290  10  5  10.0   5.5
  5750   3.4  38.1  270  11  6   1.0   0.5 |   6.5  43.7  290   9  5  13.7   7.5
  5500   3.5  38.3  260   8  4   3.1   1.7 |   7.8  46.0  290   9  4  20.3  11.2

           03/26/2015 at 1500 MDT          |       03/26/2015 at 1800 MDT
                                           |
K index... +11.5  LI... +276.3             | K index... +12.8  LI... +276.3
CAPE... 0.0  CIN... -0.9                   | 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 -57.3 -71.1  345  46 24   2.0   1.1 | -57.5 -71.5  350  50 26   2.3   1.3
 45000 -54.2 -65.6  355  61 31   1.4   0.8 | -54.0 -65.2  355  59 30  -0.2  -0.1
 40000 -54.2 -65.6  355  74 38  -0.0  -0.0 | -54.1 -65.4  355  74 38  -0.1  -0.1
 38000 -54.8 -66.6  350  77 40  -2.2  -1.2 | -54.7 -66.5  350  76 39  -1.8  -1.0
 36000 -56.1 -69.0  345  78 40  -2.2  -1.2 | -55.8 -68.4  350  73 38  -1.8  -1.0
 34000 -56.7 -70.1  340  79 41   8.6   4.7 | -55.9 -68.6  345  70 36   8.4   4.6
 32000 -52.2 -62.0  350  72 37   7.4   4.1 | -51.4 -60.5  350  67 34   7.6   4.2
 30000 -46.9 -52.4  355  67 35   9.3   5.1 | -46.2 -51.2  350  63 32   8.2   4.5
 29000 -44.1 -47.4  355  67 35   9.3   5.1 | -43.7 -46.7  355  62 32   8.2   4.5
 28000 -41.3 -42.3  360  67 35   9.3   5.1 | -41.2 -42.2  355  60 31   8.2   4.5
 27000 -38.5 -37.3  360  67 35   8.8   4.8 | -38.8 -37.8  360  59 30   8.5   4.7
 26000 -35.9 -32.6  360  68 35   8.7   4.8 | -36.2 -33.2  355  58 30   8.5   4.7
 25000 -33.3 -27.9  005  68 35   8.7   4.8 | -33.7 -28.7  355  56 29   8.5   4.7
 24000 -30.7 -23.3  005  69 35   8.2   4.5 | -31.1 -24.0  355  55 28   8.3   4.5
 23000 -28.4 -19.1  005  68 35   7.8   4.3 | -28.7 -19.7  355  56 29   8.2   4.5
 22000 -26.1 -15.0  005  68 35   7.9   4.3 | -26.3 -15.3  355  57 29   8.2   4.5
 21000 -23.9 -11.0  360  67 34   6.2   3.4 | -23.8 -10.8  355  58 30   8.5   4.7
 20000 -22.0  -7.6  360  62 32   6.3   3.4 | -21.3  -6.3  350  57 29   8.5   4.7
 19500 -21.1  -6.0  355  60 31   6.3   3.4 | -20.0  -4.0  350  56 29   8.5   4.7
 19000 -20.1  -4.2  355  58 30   6.2   3.4 | -18.8  -1.8  350  56 29   8.6   4.7
 18500 -19.2  -2.6  350  57 29   7.0   3.8 | -17.5   0.5  350  55 28   7.5   4.1
 18000 -18.1  -0.6  350  55 28   7.1   3.9 | -16.4   2.5  350  54 28   7.4   4.1
 17500 -17.1   1.2  350  54 28   7.1   3.9 | -15.3   4.5  350  53 27   7.3   4.0
 17000 -16.0   3.2  345  53 27   7.0   3.8 | -14.3   6.3  345  50 26   7.2   4.0
 16500 -15.0   5.0  345  52 27   7.1   3.9 | -13.2   8.2  345  48 25   7.3   4.0
 16000 -14.0   6.8  340  50 26   6.1   3.3 | -12.1  10.2  340  47 24   6.9   3.8
 15500 -12.7   9.1  340  45 23   6.4   3.5 | -10.6  12.9  340  45 23   6.8   3.7
 15000 -11.6  11.1  340  42 22   7.6   4.1 |  -9.7  14.5  340  43 22   6.1   3.3
 14500 -10.5  13.1  335  38 20   7.6   4.2 |  -8.8  16.2  335  40 21   6.2   3.4
 14000  -9.5  14.9  335  36 18   5.6   3.1 |  -8.0  17.6  335  37 19   4.7   2.6
 13500  -8.7  16.3  335  33 17   5.7   3.1 |  -7.3  18.9  335  34 17   4.8   2.6
 13000  -7.8  18.0  335  31 16   6.2   3.4 |  -6.6  20.1  330  30 16   5.6   3.1
 12500  -6.9  19.6  340  29 15   6.2   3.4 |  -5.8  21.6  330  27 14   5.5   3.0
 12000  -5.9  21.4  340  28 14   6.8   3.7 |  -4.9  23.2  325  24 12   6.8   3.7
 11500  -4.9  23.2  335  26 14   6.7   3.7 |  -3.9  25.0  320  21 11   6.6   3.6
 11000  -3.9  25.0  335  24 12   8.0   4.4 |  -2.8  27.0  315  20 10   8.2   4.5
 10500  -2.7  27.1  325  22 11   9.0   4.9 |  -1.6  29.1  310  20 10   9.1   5.0
 10250  -2.1  28.2  325  21 11   3.7   2.0 |  -1.0  30.2  310  21 11   4.6   2.5
 10000  -2.0  28.4  320  21 11   4.8   2.6 |  -0.8  30.6  310  21 11   6.0   3.3
  9750  -1.3  29.7  315  20 10  10.9   6.0 |   0.0  32.0  305  21 11  11.6   6.4
  9500  -0.6  30.9  310  20 10   9.1   5.0 |   0.8  33.4  305  21 11  10.2   5.6
  9250   0.0  32.0  305  19 10   6.7   3.7 |   1.5  34.7  305  20 10   7.2   3.9
  9000   0.4  32.7  305  17  9   5.8   3.2 |   1.9  35.4  305  19 10   6.2   3.4
  8750   0.9  33.6  300  15  8   8.5   4.7 |   2.5  36.5  305  17  9   9.1   5.0
  8500   1.6  34.9  300  13  6   9.1   5.0 |   3.1  37.6  305  15  8   9.2   5.0
  8250   2.2  36.0  295  11  6   9.1   5.0 |   3.8  38.8  305  13  7   8.8   4.8
  8000   2.9  37.2  295  11  6   9.2   5.1 |   4.4  39.9  305  12  6   8.8   4.8
  7750   3.6  38.5  295  11  5   9.8   5.4 |   5.1  41.2  305  11  6   9.4   5.2
  7500   4.4  39.9  295  11  5  10.2   5.6 |   5.8  42.4  305  10  5   9.9   5.4
  7250   5.1  41.2  295  11  5  10.0   5.5 |   6.6  43.9  305  10  5   9.9   5.4
  7000   5.9  42.6  295  10  5  10.1   5.5 |   7.3  45.1  305   9  5   9.9   5.4
  6750   6.6  43.9  295  10  5  10.0   5.5 |   8.0  46.4  305   9  5   9.6   5.3
  6500   7.4  45.3  295  10  5  10.2   5.6 |   8.7  47.7  305   8  4   9.4   5.2
  6250   8.1  46.6  295  10  5  10.2   5.6 |   9.4  48.9  305   8  4   9.4   5.1
  6000   8.9  48.0  295  10  5  10.3   5.7 |  10.1  50.2  305   8  4  10.0   5.5
  5750   9.8  49.6  295   9  5  14.5   8.0 |  10.9  51.6  305   7  4  11.2   6.1
  5500  11.1  52.0  295   9  4  20.8  11.4 |  11.7  53.1  305   7  3  10.9   6.0
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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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