Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 270035
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1835 MDT Thursday, March 26, 2015

This forecast is for Friday, March 27, 2015:

If the trigger temperature of 57.8 F/14.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 716 ft/min (3.6 m/s)
   Maximum height of thermals.................. 14308 ft MSL (9001 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1045 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................. 12516 ft MSL (7209 ft AGL)
Thermal soaring outlook for Saturday 03/28..... Excellent

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)................ Weak NVA
Potential height of wave....................... 27729 ft MSL (22422 ft AGL)
Wave soaring outlook for Saturday 03/28........ Poor

Remarks...

Sunrise/Sunset.................... 06:51:55 / 19:17:23 MDT
Total possible sunshine........... 12 hr 25 min 29 sec (745 min 29 sec)
Altitude of sun at 13:04:49 MDT... 52.94 degrees

Upper air data from numerical model forecast valid on 03/27/2015 at 0600 MDT

Freezing level.................. 10271 ft MSL (4964 ft AGL)
Convective condensation level... 14128 ft MSL (8821 ft AGL)
Lifted condensation level....... 14383 ft MSL (9076 ft AGL)
Lifted index.................... -0.5
K index......................... +14.6

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  -58.1 -72.6   360   59   30   3.1   1.7      M     M       M      M    M
 45000  -53.7 -64.7   360   65   34  -1.9  -1.0      M     M       M      M    M
 40000  -55.6 -68.1   350   66   34  -1.3  -0.7      M     M       M      M    M
 38000  -55.9 -68.6   350   65   33   0.2   0.1      M     M       M      M    M
 36000  -55.8 -68.4   350   62   32   0.2   0.1      M     M       M      M    M
 34000  -54.0 -65.2   350   58   30   8.2   4.5      M     M       M      M    M
 32000  -49.0 -56.2   340   52   27   8.3   4.5      M     M       M      M    M
 30000  -44.1 -47.4   340   49   25   8.2   4.5   31.3  88.3     8.5      M    M
 29000  -41.6 -42.9   340   51   26   8.2   4.5   30.6  87.0     8.1      M    M
 28000  -39.2 -38.6   345   53   27   8.2   4.5   30.0  86.0     7.7      M    M
 27000  -36.7 -34.1   345   53   28   8.4   4.6   29.5  85.1     7.4      M    M
 26000  -34.2 -29.6   345   52   27   8.4   4.6   28.9  84.0     7.0      M    M
 25000  -31.7 -25.1   345   50   26   8.4   4.6   28.4  83.1     6.7      M    M
 24000  -29.2 -20.6   340   48   25   8.2   4.5   28.0  82.4     6.4      M    M
 23000  -26.8 -16.2   340   47   24   8.2   4.5   27.3  81.2     5.9      M    M
 22000  -24.3 -11.7   340   46   24   8.2   4.5   26.8  80.2     5.5      M    M
 21000  -21.9  -7.4   340   45   23   8.2   4.5   26.3  79.3     5.2      M    M
 20000  -19.4  -2.9   340   44   23   8.2   4.5   25.7  78.2     4.7      M    M
 19500  -18.2  -0.8   340   43   22   8.2   4.5   25.4  77.7     4.5      M    M
 19000  -17.0   1.4   340   43   22   8.3   4.6   25.2  77.3     4.3      M    M
 18500  -15.8   3.6   340   42   22   7.0   3.9   24.9  76.7     4.0      M    M
 18000  -14.8   5.4   340   42   21   7.1   3.9   24.4  75.9     3.6      M    M
 17500  -13.2   8.2   340   41   21   7.7   4.2   23.7  74.7     3.1      M    M
 17000  -12.0  10.4   340   40   21   7.7   4.2   23.4  74.0     2.7      M    M
 16500  -10.9  12.4   340   40   20   7.0   3.9   23.0  73.4     2.4      M    M
 16000  -10.0  14.0   335   38   20   6.6   3.6   22.5  72.4     1.9      M    M
 15500   -9.0  15.8   335   37   19   6.3   3.5   21.9  71.5     1.4      M    M
 15000   -8.2  17.2   335   36   19   5.4   3.0   21.2  70.2     0.8      M    M
 14500   -7.4  18.7   340   36   18   5.5   3.0   20.5  68.9     0.2      M    M
 14000   -6.6  20.1   340   35   18   4.5   2.5   19.7  67.5    -0.6    689  3.5
 13500   -6.0  21.2   340   33   17   4.7   2.6   18.9  66.0    -1.4    654  3.3
 13000   -5.3  22.5   340   32   16   4.2   2.3   18.0  64.4    -2.2    621  3.2
 12500   -4.7  23.5   340   30   15   3.9   2.2   17.1  62.8    -3.1    588  3.0
 12000   -4.0  24.8   345   29   15   7.2   4.0   16.4  61.6    -3.8    549  2.8
 11500   -2.9  26.8   345   29   15   7.1   3.9   16.0  60.8    -4.2    503  2.6
 11000   -1.8  28.8   350   29   15   8.6   4.7   15.7  60.2    -4.6    454  2.3
 10500   -0.5  31.1   350   30   15   9.6   5.3   15.5  59.9    -4.8    402  2.0
 10250    0.1  32.2   350   30   15   4.2   2.3   15.4  59.7    -5.0    376  1.9
 10000    0.3  32.5   350   30   15   5.6   3.1   14.8  58.6    -5.5    364  1.8
  9750    1.0  33.8   350   29   15  12.0   6.6   14.9  58.7    -5.5    333  1.7
  9500    1.8  35.2   350   28   14  10.3   5.7   14.9  58.9    -5.4    302  1.5
  9250    2.6  36.7   350   27   14   8.0   4.4   14.9  58.9    -5.5    272  1.4
  9000    3.1  37.6   345   26   13   6.6   3.6   14.7  58.4    -5.7    250  1.3
  8750    3.6  38.5   345   25   13   8.6   4.7   14.5  58.2    -5.9    226  1.1
  8500    4.3  39.7   340   24   12   8.2   4.5   14.4  58.0    -6.0    199  1.0
  8250    4.8  40.6   335   23   12   6.6   3.6   14.3  57.7    -6.2    175  0.9
  8000    5.3  41.5   330   23   12   6.2   3.4   14.0  57.2    -6.5    154  0.8
  7750    5.7  42.3   320   24   12   5.4   2.9   13.7  56.7    -6.8    134  0.7
  7500    6.1  43.0   315   25   13   5.7   3.1   13.3  56.0    -7.2    116  0.6
  7250    6.5  43.7   315   25   13   6.7   3.7   13.1  55.6    -7.5     94  0.5
  7000    7.0  44.6   310   24   12   6.5   3.5   12.8  55.1    -7.7     72  0.4
  6750    7.5  45.5   310   24   12   6.6   3.6   12.6  54.7    -8.0     50  0.3
  6500    8.0  46.4   310   23   12   5.7   3.1   12.3  54.2    -8.3     29  0.1
  6250    8.4  47.1   305   20   11   6.9   3.8   12.0  53.7    -8.6      9  0.0
  6000    8.8  47.8   305   18    9   1.2   0.7   11.7  53.1    -8.9      M    M
  5750    8.3  46.9   300   15    8 -13.6  -7.4   10.5  50.9   -10.2      M    M
  5500    6.9  44.4   285    9    4 -20.4 -11.2    8.4  47.2   -12.3     31  0.2

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

           03/27/2015 at 0900 MDT          |       03/27/2015 at 1200 MDT
                                           |
K index... +14.4  LI... +276.2             | K index... +15.3  LI... +275.2
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 -58.5 -73.3  005  60 31   3.6   2.0 | -59.8 -75.6  360  55 28   3.2   1.8
 45000 -53.4 -64.1  360  69 35  -1.2  -0.7 | -55.0 -67.0  355  64 33   1.6   0.9
 40000 -54.4 -65.9  355  64 33  -0.7  -0.4 | -52.7 -62.9  350  65 34   1.5   0.8
 38000 -54.9 -66.8  350  63 33  -0.8  -0.5 | -53.1 -63.6  345  62 32  -1.8  -1.0
 36000 -55.3 -67.5  345  63 32  -0.8  -0.5 | -54.2 -65.6  345  56 29  -1.8  -1.0
 34000 -54.2 -65.6  345  62 32   8.4   4.6 | -53.5 -64.3  340  51 26   8.1   4.4
 32000 -49.0 -56.2  345  58 30   8.6   4.7 | -48.5 -55.3  340  49 25   8.3   4.5
 30000 -43.9 -47.0  345  55 28   8.6   4.7 | -43.0 -45.4  335  47 24   8.1   4.5
 29000 -40.7 -41.3  345  53 27   8.6   4.7 | -40.6 -41.1  335  47 24   8.2   4.5
 28000 -38.1 -36.6  345  52 27   8.6   4.7 | -38.1 -36.6  335  47 24   8.2   4.5
 27000 -35.6 -32.1  345  50 26   7.9   4.3 | -35.7 -32.3  335  46 24   7.8   4.3
 26000 -33.2 -27.8  340  49 25   7.9   4.3 | -33.4 -28.1  335  44 23   7.9   4.3
 25000 -30.9 -23.6  340  47 24   7.9   4.3 | -31.0 -23.8  330  42 22   7.9   4.3
 24000 -28.5 -19.3  340  46 23   7.8   4.3 | -28.7 -19.7  330  41 21   8.0   4.4
 23000 -26.2 -15.2  335  45 23   7.8   4.3 | -26.3 -15.3  335  42 22   8.0   4.4
 22000 -23.9 -11.0  330  44 23   7.8   4.3 | -23.9 -11.0  335  43 22   8.0   4.4
 21000 -21.6  -6.9  330  43 22   6.9   3.8 | -21.6  -6.9  335  42 22   7.8   4.3
 20000 -19.6  -3.3  325  40 21   7.0   3.8 | -19.3  -2.7  330  41 21   7.8   4.3
 19500 -18.5  -1.3  325  39 20   7.0   3.8 | -18.1  -0.6  325  40 20   7.9   4.3
 19000 -17.5   0.5  325  38 20   6.9   3.8 | -17.0   1.4  325  39 20   7.9   4.3
 18500 -16.4   2.5  325  38 19   8.1   4.4 | -15.9   3.4  320  38 19   7.0   3.8
 18000 -15.2   4.6  325  37 19   8.0   4.4 | -14.8   5.4  320  36 19   7.1   3.9
 17500 -14.0   6.8  325  37 19   7.6   4.2 | -13.8   7.2  315  35 18   6.9   3.8
 17000 -12.9   8.8  330  36 18   7.4   4.1 | -12.8   9.0  320  33 17   6.8   3.7
 16500 -11.9  10.6  330  35 18   7.3   4.0 | -11.8  10.8  320  31 16   6.9   3.8
 16000 -10.8  12.6  330  35 18   7.0   3.9 | -10.2  13.6  320  29 15   7.2   4.0
 15500  -9.8  14.4  335  35 18   7.1   3.9 |  -9.1  15.6  325  28 14   7.1   3.9
 15000  -8.3  17.1  335  34 17   6.7   3.7 |  -8.1  17.4  325  28 14   6.9   3.8
 14500  -7.3  18.9  340  33 17   6.7   3.7 |  -7.0  19.4  330  27 14   6.9   3.8
 14000  -6.3  20.7  340  33 17   6.8   3.7 |  -6.0  21.2  330  26 14   6.8   3.7
 13500  -5.3  22.5  340  33 17   6.8   3.7 |  -5.0  23.0  335  25 13   6.8   3.7
 13000  -4.4  24.1  340  33 17   5.3   2.9 |  -4.1  24.6  335  25 13   6.3   3.5
 12500  -3.6  25.5  345  32 17   5.2   2.9 |  -3.1  26.4  340  24 12   6.3   3.4
 12000  -2.7  27.1  345  32 16   7.6   4.2 |  -2.1  28.2  340  23 12   8.1   4.5
 11500  -1.6  29.1  345  31 16   7.5   4.1 |  -0.9  30.4  340  22 11   8.0   4.4
 11000  -0.6  30.9  345  30 16   5.8   3.2 |   0.2  32.4  340  20 10   7.4   4.1
 10500   0.2  32.4  350  28 15   6.2   3.4 |   1.3  34.3  345  19 10   7.4   4.1
 10250   0.6  33.1  350  27 14   3.5   1.9 |   1.8  35.2  345  19 10   3.9   2.1
 10000   0.9  33.6  350  27 14   6.3   3.5 |   2.1  35.8  340  18  9   7.3   4.0
  9750   1.6  34.9  350  25 13  10.8   5.9 |   2.9  37.2  340  17  9  12.4   6.8
  9500   2.3  36.1  350  23 12   9.1   5.0 |   3.8  38.8  335  16  8  10.4   5.7
  9250   2.9  37.2  345  22 11   6.6   3.6 |   4.5  40.1  330  15  8   7.9   4.4
  9000   3.3  37.9  345  20 10   6.3   3.5 |   5.0  41.0  325  16  8   7.6   4.2
  8750   3.9  39.0  340  19 10   9.3   5.1 |   5.7  42.3  320  16  8  10.5   5.7
  8500   4.6  40.3  340  17  9   8.6   4.7 |   6.4  43.5  315  17  9   7.8   4.3
  8250   5.2  41.4  330  17  9   6.8   3.8 |   6.8  44.2  310  17  9   3.8   2.1
  8000   5.7  42.3  325  18  9   6.6   3.6 |   7.0  44.6  305  18  9   3.3   1.8
  7750   6.1  43.0  320  19 10   6.2   3.4 |   7.2  45.0  300  18  9   1.8   1.0
  7500   6.6  43.9  315  21 11   4.1   2.3 |   7.3  45.1  295  17  9   4.0   2.2
  7250   6.8  44.2  310  21 11   2.9   1.6 |   7.7  45.9  295  15  8   6.7   3.7
  7000   7.0  44.6  305  21 11   3.0   1.7 |   8.1  46.6  290  13  7   5.7   3.2
  6750   7.2  45.0  300  21 11   3.8   2.1 |   8.6  47.5  290  11  6   7.5   4.1
  6500   7.5  45.5  295  19 10   5.1   2.8 |   9.2  48.6  290  10  5   9.5   5.2
  6250   7.9  46.2  295  17  9   6.6   3.6 |   9.9  49.8  290   9  5   9.5   5.2
  6000   8.3  46.9  295  15  8   2.1   1.2 |  10.6  51.1  290   9  5   9.7   5.3
  5750   8.1  46.6  285  11  6  -6.2  -3.4 |  11.4  52.5  290   8  4  13.3   7.3
  5500   7.5  45.5  270   8  4  -6.9  -3.8 |  12.5  54.5  285   8  4  18.2  10.0

           03/27/2015 at 1500 MDT          |       03/27/2015 at 1800 MDT
                                           |
K index... +15.8  LI... +273.3             | K index... +19.4  LI... +271.6
CAPE... 0.0  CIN... -1.3                   | CAPE... +155.4  CIN... -34.7
                                           |
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 -59.9 -75.8  005  50 26   3.3   1.8 | -59.6 -75.3  360  47 24   3.8   2.1
 45000 -54.9 -66.8  355  56 29   2.2   1.2 | -54.1 -65.4  355  53 27   2.7   1.5
 40000 -51.7 -61.1  350  66 34   2.1   1.2 | -50.0 -58.0  350  69 36   2.7   1.5
 38000 -52.1 -61.8  345  61 31  -2.1  -1.1 | -50.4 -58.7  345  66 34  -2.3  -1.3
 36000 -53.3 -63.9  340  51 26  -2.1  -1.1 | -51.8 -61.2  345  57 29  -2.3  -1.3
 34000 -52.7 -62.9  335  43 22   8.1   4.4 | -51.0 -59.8  345  48 24   7.7   4.2
 32000 -47.1 -52.8  330  40 20   8.3   4.6 | -46.4 -51.5  340  41 21   7.6   4.2
 30000 -42.3 -44.1  330  39 20   7.7   4.2 | -41.9 -43.4  335  37 19   7.2   3.9
 29000 -40.0 -40.0  330  39 20   7.7   4.2 | -39.8 -39.6  335  37 19   7.2   3.9
 28000 -37.7 -35.9  330  39 20   7.7   4.2 | -37.6 -35.7  330  37 19   7.2   3.9
 27000 -35.4 -31.7  330  40 20   7.4   4.1 | -35.4 -31.7  330  37 19   7.8   4.3
 26000 -33.2 -27.8  330  40 20   7.5   4.1 | -33.1 -27.6  330  38 20   7.8   4.3
 25000 -30.9 -23.6  325  40 20   7.5   4.1 | -30.8 -23.4  325  39 20   7.8   4.3
 24000 -28.7 -19.7  325  39 20   7.8   4.3 | -28.5 -19.3  325  39 20   7.0   3.8
 23000 -26.4 -15.5  325  39 20   7.8   4.3 | -26.4 -15.5  325  36 18   7.0   3.8
 22000 -24.0 -11.2  325  38 19   7.9   4.3 | -24.3 -11.7  320  33 17   7.0   3.9
 21000 -21.7  -7.1  325  37 19   7.9   4.3 | -22.2  -8.0  320  31 16   7.9   4.3
 20000 -19.4  -2.9  325  36 18   7.9   4.3 | -19.8  -3.6  325  33 17   7.9   4.3
 19500 -18.2  -0.8  325  35 18   7.9   4.3 | -18.7  -1.7  325  34 17   7.9   4.3
 19000 -17.0   1.4  325  34 18   8.0   4.4 | -17.5   0.5  325  35 18   7.9   4.3
 18500 -15.9   3.4  320  34 17   7.1   3.9 | -16.3   2.7  325  35 18   7.7   4.2
 18000 -14.9   5.2  320  33 17   7.1   3.9 | -14.6   5.7  325  34 18   7.8   4.3
 17500 -13.8   7.2  320  33 17   7.6   4.2 | -13.5   7.7  325  34 17   7.5   4.1
 17000 -12.6   9.3  320  32 16   7.8   4.3 | -12.4   9.7  330  33 17   7.5   4.1
 16500 -10.9  12.4  315  30 15   7.7   4.2 | -11.2  11.8  330  33 17   8.1   4.4
 16000  -9.8  14.4  315  29 15   7.6   4.2 | -10.0  14.0  330  33 17   8.2   4.5
 15500  -8.6  16.5  315  27 14   7.6   4.1 |  -8.8  16.2  335  33 17   8.0   4.4
 15000  -7.5  18.5  315  26 13   7.5   4.1 |  -7.6  18.3  335  33 17   7.6   4.2
 14500  -6.4  20.5  315  25 13   7.4   4.1 |  -6.5  20.3  335  33 17   7.7   4.2
 14000  -5.3  22.5  320  24 12   7.1   3.9 |  -5.3  22.5  335  33 17   8.3   4.6
 13500  -4.3  24.3  320  22 11   7.2   3.9 |  -4.1  24.6  340  32 16   8.3   4.6
 13000  -3.2  26.2  320  21 11   7.4   4.1 |  -2.9  26.8  340  31 16   7.7   4.2
 12500  -2.1  28.2  320  20 10   7.4   4.1 |  -1.8  28.8  340  30 16   7.7   4.2
 12000  -1.0  30.2  320  18  9   7.7   4.2 |  -0.6  30.9  340  29 15   8.5   4.7
 11500   0.1  32.2  320  16  8   7.6   4.2 |   0.7  33.3  335  27 14   8.6   4.7
 11000   1.4  34.5  315  16  8   9.2   5.0 |   1.8  35.2  335  25 13   7.8   4.3
 10500   2.7  36.9  315  16  8   9.3   5.1 |   2.9  37.2  330  22 11   8.2   4.5
 10250   3.3  37.9  315  16  8   3.7   2.1 |   3.5  38.3  330  21 11   4.4   2.4
 10000   3.4  38.1  315  17  9   5.1   2.8 |   3.7  38.7  325  20 10   6.8   3.7
  9750   4.1  39.4  310  18  9  10.6   5.8 |   4.5  40.1  325  20 10  11.7   6.4
  9500   4.8  40.6  310  19 10   8.7   4.8 |   5.3  41.5  320  19 10  10.3   5.6
  9250   5.3  41.5  305  20 10   5.2   2.8 |   6.0  42.8  320  18  9   8.0   4.4
  9000   5.5  41.9  305  19 10   4.1   2.2 |   6.5  43.7  315  18  9   7.3   4.0
  8750   5.9  42.6  305  18  9   5.8   3.2 |   7.1  44.8  315  17  9   8.9   4.9
  8500   6.3  43.3  300  16  8   6.7   3.7 |   7.7  45.9  315  15  8   8.7   4.8
  8250   6.9  44.4  300  14  7   8.9   4.9 |   8.3  46.9  315  14  7   8.7   4.8
  8000   7.5  45.5  300  14  7   9.5   5.2 |   9.0  48.2  310  13  7   8.8   4.8
  7750   8.2  46.8  300  13  7  10.1   5.5 |   9.6  49.3  310  12  6   9.1   5.0
  7500   9.0  48.2  300  13  7  10.2   5.6 |  10.3  50.5  310  11  6   9.4   5.2
  7250   9.7  49.5  300  13  7   9.9   5.4 |  11.0  51.8  310  11  6   9.6   5.3
  7000  10.5  50.9  300  13  7   9.9   5.5 |  11.7  53.1  310  11  5   9.5   5.2
  6750  11.2  52.2  300  12  6  10.1   5.6 |  12.4  54.3  310  10  5   9.4   5.2
  6500  12.0  53.6  300  12  6  10.3   5.7 |  13.1  55.6  310  10  5   9.8   5.4
  6250  12.8  55.0  300  12  6  10.3   5.7 |  13.9  57.0  310  10  5  10.2   5.6
  6000  13.5  56.3  300  12  6  10.4   5.7 |  14.6  58.3  310   9  5   9.7   5.3
  5750  14.4  57.9  300  11  6  13.5   7.4 |  15.3  59.5  310   9  5   9.4   5.2
  5500  15.5  59.9  300  10  5  18.5  10.2 |  16.0  60.8  310   8  4  10.4   5.7
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613



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