Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251234
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0534 MST Wednesday, February 25, 2015

This forecast is for Wednesday, February 25, 2015:

If the trigger temperature of 42.1 F/5.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7883 ft MSL (714 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... None
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................. 7507 ft MSL (337 ft AGL)
Thermal soaring outlook for Thursday 02/26..... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:37:15 / 17:46:06 MST
Total possible sunshine........... 11 hr 8 min 52 sec (668 min 52 sec)
Altitude of sun at 12:11:56 MST... 42.08 degrees

Upper air data from numerical model forecast valid on 02/25/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 16331 ft MSL (9162 ft AGL)
Lifted condensation level....... 12339 ft MSL (5170 ft AGL)
Lifted index.................... +9.1
K index......................... +9.1

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  -56.2 -69.2   295   25   13   1.3   0.7      M     M       M      M    M
 45000  -54.1 -65.4   300   35   18   1.3   0.7      M     M       M      M    M
 40000  -52.3 -62.1   300   44   23   1.2   0.7      M     M       M      M    M
 38000  -52.3 -62.1   300   48   24  -3.8  -2.1      M     M       M      M    M
 36000  -54.6 -66.3   300   49   25  -3.9  -2.1      M     M       M      M    M
 34000  -56.9 -70.4   300   51   26  -5.0  -2.8      M     M       M      M    M
 32000  -53.5 -64.3   300   45   23   7.0   3.8      M     M       M      M    M
 30000  -49.3 -56.7   300   38   20   7.4   4.0      M     M       M      M    M
 29000  -46.8 -52.2   300   38   20   8.7   4.8   20.1  68.1    14.2      M    M
 28000  -43.5 -46.3   305   39   20   8.7   4.8   19.6  67.2    14.0      M    M
 27000  -40.9 -41.6   305   40   21   8.8   4.8   19.3  66.7    14.0      M    M
 26000  -38.4 -37.1   305   41   21   8.2   4.5   18.7  65.7    13.7      M    M
 25000  -35.9 -32.6   310   42   21   8.2   4.5   18.1  64.6    13.4      M    M
 24000  -33.5 -28.3   310   42   22   8.2   4.5   17.6  63.7    13.1      M    M
 23000  -31.1 -24.0   310   42   22   7.9   4.3   16.9  62.5    12.7      M    M
 22000  -28.7 -19.7   310   41   21   7.9   4.3   16.2  61.2    12.3      M    M
 21000  -26.3 -15.3   310   40   20   7.9   4.3   15.6  60.2    11.9      M    M
 20000  -24.1 -11.4   315   39   20   7.6   4.2   14.9  58.7    11.3      M    M
 19500  -22.9  -9.2   315   38   20   7.6   4.2   14.5  58.1    11.1      M    M
 19000  -21.8  -7.2   315   38   20   7.6   4.2   14.1  57.4    10.8      M    M
 18500  -20.7  -5.3   315   38   19   7.7   4.2   13.8  56.9    10.6      M    M
 18000  -19.5  -3.1   315   37   19   7.4   4.0   13.4  56.2    10.3      M    M
 17500  -18.4  -1.1   315   36   18   7.4   4.1   13.0  55.5    10.0      M    M
 17000  -17.3   0.9   315   35   18   7.9   4.4   12.7  54.8     9.7      M    M
 16500  -16.1   3.0   310   33   17   8.3   4.5   12.4  54.3     9.5      M    M
 16000  -14.9   5.2   310   31   16   8.2   4.5   12.2  53.9     9.3      M    M
 15500  -13.7   7.3   305   29   15   7.5   4.1   11.8  53.3     9.1      M    M
 15000  -12.6   9.3   305   27   14   8.0   4.4   11.5  52.7     8.8      M    M
 14500  -11.8  10.8   310   25   13   3.6   2.0   10.8  51.5     8.2      M    M
 14000  -11.2  11.8   315   23   12   4.0   2.2    9.9  49.8     7.4      M    M
 13500  -10.6  12.9   320   22   11   3.8   2.1    9.0  48.2     6.5      M    M
 13000  -10.1  13.8   330   21   11   3.7   2.0    8.0  46.4     5.6      M    M
 12500   -9.4  15.1   335   21   11   5.8   3.2    7.2  44.9     4.8      M    M
 12000   -8.5  16.7   345   23   12   6.2   3.4    6.6  43.9     4.4      M    M
 11750   -8.0  17.6   345   23   12   6.4   3.5    6.4  43.4     4.1      M    M
 11500   -7.5  18.5   350   24   12   7.9   4.3    6.1  43.1     3.9      M    M
 11250   -6.8  19.8   350   25   13   8.5   4.7    6.0  42.9     3.8      M    M
 11000   -6.2  20.8   350   26   13   8.6   4.7    5.9  42.7     3.7      M    M
 10750   -5.5  22.1   350   26   13   9.4   5.2    5.9  42.6     3.7      M    M
 10500   -4.8  23.4   350   27   14   9.4   5.2    5.9  42.6     3.7      M    M
 10250   -3.4  25.9   350   27   14   9.4   5.2    5.8  42.4     3.6      M    M
 10000   -2.7  27.1   350   28   14   8.4   4.6    5.7  42.3     3.6      M    M
  9750   -2.2  28.0   345   28   15   5.9   3.2    5.5  41.9     3.4      M    M
  9500   -1.8  28.8   340   29   15   5.2   2.8    5.2  41.3     3.1      M    M
  9250   -1.4  29.5   335   30   15   5.1   2.8    4.8  40.7     2.7      M    M
  9000   -1.0  30.2   335   31   16   6.0   3.3    4.5  40.1     2.4      M    M
  8750   -0.6  30.9   330   30   15   3.6   2.0    4.2  39.5     2.1      M    M
  8500   -0.5  31.1   325   29   15   1.2   0.6    3.5  38.4     1.5      M    M
  8250   -0.4  31.3   325   28   14   0.9   0.5    2.9  37.3     0.9      M    M
  8000   -0.4  31.3   320   27   14  -0.1  -0.0    2.2  36.0     0.1      M    M
  7750   -0.8  30.6   320   24   12 -16.6  -9.1    1.1  33.9    -1.0     64  0.3
  7500   -3.2  26.2   315   17    9 -45.0 -24.7   -2.1  28.3    -4.2    129  0.7
  7250   -5.6  21.9   310   10    5   5.8   3.2   -5.2  22.7    -7.3    193  1.0
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           02/25/2015 at 0800 MST          |       02/25/2015 at 1100 MST
                                           |
K index... +9.8  LI... +2.2                | K index... +8.5  LI... +3.4
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... -0.4
                                           |
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 -55.7 -68.3  305  28 14   2.0   1.1 | -55.4 -67.7  290  42 21   2.4   1.3
 45000 -52.5 -62.5  310  31 16   2.0   1.1 | -51.8 -61.2  300  46 23   2.4   1.3
 40000 -50.1 -58.2  305  41 21   1.6   0.9 | -48.6 -55.5  300  49 25   2.0   1.1
 38000 -50.1 -58.2  300  46 24  -6.8  -3.7 | -48.2 -54.8  295  51 26  -6.2  -3.4
 36000 -54.0 -65.2  295  52 27  -6.5  -3.5 | -51.6 -60.9  290  59 30  -5.6  -3.1
 34000 -57.9 -72.2  290  59 30  -7.5  -4.1 | -55.0 -67.0  285  67 34  -5.4  -3.0
 32000 -54.6 -66.3  290  59 31   8.0   4.4 | -53.9 -65.0  285  66 34   4.1   2.2
 30000 -49.8 -57.6  285  59 30   8.1   4.4 | -51.5 -60.7  285  63 32   3.8   2.1
 29000 -47.1 -52.8  285  59 30   9.1   5.0 | -48.7 -55.7  285  61 32   8.7   4.8
 28000 -43.7 -46.7  285  58 30   9.1   5.0 | -46.1 -51.0  290  60 31   8.7   4.8
 27000 -41.0 -41.8  290  58 30   9.2   5.0 | -43.5 -46.3  290  60 31   8.6   4.7
 26000 -38.7 -37.7  295  56 29   6.5   3.6 | -41.2 -42.2  290  57 29   7.1   3.9
 25000 -36.8 -34.2  300  54 28   6.5   3.6 | -39.1 -38.4  290  52 27   7.0   3.9
 24000 -34.8 -30.6  305  53 27   6.5   3.6 | -37.0 -34.6  290  47 24   7.1   3.9
 23000 -32.7 -26.9  305  50 26   7.3   4.0 | -34.8 -30.6  290  42 21   7.6   4.2
 22000 -30.5 -22.9  305  46 24   7.3   4.0 | -32.5 -26.5  285  36 19   7.6   4.2
 21000 -28.3 -18.9  305  42 22   7.4   4.0 | -30.2 -22.4  280  32 16   7.6   4.2
 20000 -26.2 -15.2  305  38 19   7.3   4.0 | -27.9 -18.2  275  29 15   7.9   4.4
 19500 -25.1 -13.2  305  35 18   7.3   4.0 | -26.7 -16.1  275  29 15   7.9   4.4
 19000 -24.0 -11.2  305  33 17   7.3   4.0 | -25.6 -14.1  275  28 14   8.0   4.4
 18500 -22.9  -9.2  300  31 16   7.2   4.0 | -24.4 -11.9  275  27 14   8.0   4.4
 18000 -21.8  -7.2  300  29 15   8.2   4.5 | -23.2  -9.8  275  27 14   7.1   3.9
 17500 -20.6  -5.1  295  27 14   8.2   4.5 | -22.2  -8.0  280  25 13   6.9   3.8
 17000 -19.4  -2.9  295  25 13   7.8   4.3 | -21.2  -6.2  290  24 12   6.7   3.7
 16500 -18.2  -0.8  295  24 12   7.5   4.1 | -20.2  -4.4  300  24 12   6.4   3.5
 16000 -17.1   1.2  295  23 12   7.3   4.0 | -19.2  -2.6  305  25 13   6.3   3.5
 15500 -16.2   2.8  300  23 12   6.1   3.3 | -18.2  -0.8  315  27 14   7.2   3.9
 15000 -15.3   4.5  305  22 11   6.1   3.3 | -17.2   1.0  325  29 15   7.1   3.9
 14500 -14.3   6.3  315  22 11   6.5   3.6 | -15.6   3.9  330  32 17   7.4   4.0
 14000 -13.4   7.9  325  23 12   6.3   3.5 | -14.5   5.9  335  35 18   7.3   4.0
 13500 -12.3   9.9  330  24 12   8.0   4.4 | -13.4   7.9  335  37 19   6.5   3.6
 13000 -11.1  12.0  340  27 14   8.1   4.5 | -12.5   9.5  335  37 19   6.6   3.6
 12500  -9.8  14.4  345  29 15   8.8   4.8 | -11.5  11.3  340  37 19   7.0   3.9
 12000  -8.5  16.7  345  33 17   8.3   4.5 | -10.6  12.9  340  37 19   5.1   2.8
 11750  -7.9  17.8  345  34 18   7.6   4.2 | -10.2  13.6  340  37 19   5.8   3.2
 11500  -7.3  18.9  345  36 18   7.9   4.3 |  -9.7  14.5  340  36 18   6.6   3.6
 11250  -6.7  19.9  345  37 19   7.9   4.3 |  -9.3  15.3  345  35 18   6.4   3.5
 11000  -6.2  20.8  345  39 20   7.9   4.3 |  -8.8  16.2  345  34 18   6.4   3.5
 10750  -5.6  21.9  340  40 21   6.4   3.5 |  -8.3  17.1  345  33 17   6.7   3.7
 10500  -5.2  22.6  340  40 21   4.4   2.4 |  -7.8  18.0  345  32 16   6.9   3.8
 10250  -4.6  23.7  335  39 20   4.6   2.5 |  -7.3  18.9  345  31 16   7.0   3.8
 10000  -4.3  24.3  335  39 20   2.5   1.4 |  -6.8  19.8  345  30 15   6.6   3.6
  9750  -4.2  24.4  335  38 19   1.7   0.9 |  -6.3  20.7  345  29 15   6.6   3.6
  9500  -4.0  24.8  335  36 18   3.3   1.8 |  -5.8  21.6  345  28 15   6.9   3.8
  9250  -3.8  25.2  330  34 17   2.5   1.4 |  -5.3  22.5  345  27 14   7.1   3.9
  9000  -3.6  25.5  330  32 17   4.4   2.4 |  -4.8  23.4  350  27 14   6.0   3.3
  8750  -3.2  26.2  330  30 16   5.9   3.2 |  -4.4  24.1  350  25 13   6.7   3.7
  8500  -2.8  27.0  335  29 15   5.7   3.1 |  -3.8  25.2  350  23 12   8.4   4.6
  8250  -2.3  27.9  335  27 14   4.4   2.4 |  -3.2  26.2  350  21 11   8.0   4.4
  8000  -2.2  28.0  335  25 13   1.4   0.8 |  -2.6  27.3  350  19 10   8.0   4.4
  7750  -2.3  27.9  335  23 12  -5.3  -2.9 |  -2.1  28.2  350  16  8   7.9   4.4
  7500  -3.1  26.4  335  17  9 -14.3  -7.8 |  -1.5  29.3  350  14  7   8.8   4.8
  7250  -3.9  25.0  335  10  5   1.3   0.7 |  -0.9  30.4  350  12  6   7.1   3.9
  7000     M     M    M   M  M     M     M |  -0.6  30.9  350  10  5   2.6   1.4
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/25/2015 at 1400 MST          |       02/25/2015 at 1700 MST
                                           |
K index... +13.8  LI... +1.4               | K index... +16.4  LI... +0.2
CAPE... 0.0  CIN... -1.5                   | CAPE... +7.3  CIN... -2.8
                                           |
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  300  47 24   2.6   1.4 | -53.8 -64.8  305  39 20   1.9   1.1
 45000 -52.2 -62.0  300  58 30   2.6   1.4 | -51.0 -59.8  300  57 29   1.9   1.1
 40000 -49.1 -56.4  295  55 28   1.9   1.0 | -49.5 -57.1  300  58 30   0.8   0.4
 38000 -48.3 -54.9  295  54 28  -2.7  -1.5 | -49.1 -56.4  300  57 30  -0.7  -0.4
 36000 -49.7 -57.5  290  57 30  -2.3  -1.3 | -49.5 -57.1  300  55 28  -0.7  -0.4
 34000 -51.1 -60.0  290  61 31  -2.3  -1.2 | -49.9 -57.8  295  53 27  -0.7  -0.4
 32000 -51.5 -60.7  285  62 32  -0.1  -0.0 | -50.7 -59.3  295  51 26  -1.8  -1.0
 30000 -51.6 -60.9  280  62 32   0.1   0.0 | -51.8 -61.2  290  50 26  -1.7  -0.9
 29000 -49.8 -57.6  280  60 31   8.0   4.4 | -51.1 -60.0  285  48 25   5.6   3.1
 28000 -47.4 -53.3  280  57 29   7.9   4.4 | -49.4 -56.9  290  46 24   5.7   3.1
 27000 -45.0 -49.0  280  54 28   7.9   4.3 | -47.6 -53.7  290  45 23   5.7   3.1
 26000 -42.7 -44.9  280  51 26   7.2   3.9 | -45.7 -50.3  290  43 22   9.1   5.0
 25000 -40.6 -41.1  280  48 25   7.2   3.9 | -43.1 -45.6  290  42 22   8.7   4.8
 24000 -38.4 -37.1  285  45 23   7.2   4.0 | -40.5 -40.9  290  42 22   8.7   4.8
 23000 -36.1 -33.0  285  42 21   8.8   4.8 | -37.9 -36.2  295  41 21   7.6   4.2
 22000 -33.5 -28.3  285  39 20   8.7   4.8 | -35.6 -32.1  295  41 21   7.8   4.3
 21000 -30.9 -23.6  290  36 18   8.7   4.8 | -33.3 -27.9  300  41 21   7.8   4.3
 20000 -28.7 -19.7  290  33 17   6.4   3.5 | -31.0 -23.8  300  40 21   7.9   4.3
 19500 -27.8 -18.0  290  31 16   6.4   3.5 | -29.8 -21.6  300  40 20   7.9   4.3
 19000 -26.8 -16.2  290  30 15   6.4   3.5 | -28.6 -19.5  300  39 20   7.9   4.3
 18500 -25.9 -14.6  290  28 14   6.5   3.5 | -27.5 -17.5  300  38 20   7.9   4.3
 18000 -24.9 -12.8  295  27 14   7.1   3.9 | -26.3 -15.3  300  37 19   8.0   4.4
 17500 -23.8 -10.8  300  28 14   7.5   4.1 | -25.1 -13.2  300  36 19   8.1   4.5
 17000 -22.7  -8.9  305  29 15   7.3   4.0 | -23.9 -11.0  300  36 18   8.2   4.5
 16500 -21.7  -7.1  310  30 16   5.9   3.3 | -22.6  -8.7  295  34 17   8.8   4.8
 16000 -20.9  -5.6  315  32 17   5.9   3.2 | -21.3  -6.3  295  31 16   8.8   4.8
 15500 -19.9  -3.8  315  34 17   7.7   4.2 | -20.0  -4.0  295  29 15   8.8   4.8
 15000 -18.7  -1.7  315  35 18   7.6   4.2 | -18.7  -1.7  295  28 14   8.9   4.9
 14500 -17.0   1.4  315  35 18   7.8   4.3 | -17.0   1.4  300  26 14   6.8   3.7
 14000 -15.9   3.4  315  35 18   7.8   4.3 | -15.9   3.4  300  26 13   7.1   3.9
 13500 -14.7   5.5  315  34 17   8.0   4.4 | -15.1   4.8  305  24 13   4.8   2.7
 13000 -13.5   7.7  315  32 16   8.1   4.4 | -14.3   6.3  315  23 12   5.1   2.8
 12500 -12.4   9.7  320  30 15   7.5   4.1 | -13.6   7.5  325  21 11   4.4   2.4
 12000 -11.4  11.5  320  28 15   6.3   3.4 | -13.0   8.6  335  21 11   4.4   2.4
 11750 -10.9  12.4  320  27 14   5.5   3.0 | -12.6   9.3  340  21 11   4.7   2.6
 11500 -10.5  13.1  325  27 14   5.1   2.8 | -12.3   9.9  350  21 11   5.1   2.8
 11250 -10.2  13.6  330  26 13   5.3   2.9 | -11.9  10.6  355  22 11   5.1   2.8
 11000  -9.8  14.4  335  25 13   4.9   2.7 | -11.5  11.3  360  23 12   4.8   2.7
 10750  -9.4  15.1  335  26 13   4.5   2.5 | -11.2  11.8  005  25 13   5.2   2.9
 10500  -9.1  15.6  340  25 13   4.6   2.5 | -10.7  12.7  005  25 13   5.8   3.2
 10250  -8.8  16.2  345  25 13   4.5   2.5 | -10.3  13.5  010  26 13   5.6   3.1
 10000  -8.4  16.9  350  25 13   4.8   2.7 |  -9.9  14.2  015  27 14   6.0   3.3
  9750  -8.0  17.6  355  25 13   6.2   3.4 |  -9.4  15.1  015  26 14   6.6   3.6
  9500  -7.5  18.5  360  24 13   6.9   3.8 |  -9.0  15.8  015  26 13   6.7   3.7
  9250  -7.0  19.4  360  24 13   6.8   3.7 |  -8.5  16.7  015  26 13   6.9   3.8
  9000  -6.6  20.1  005  24 13   6.6   3.6 |  -8.0  17.6  015  25 13   6.3   3.4
  8750  -6.1  21.0  005  23 12   8.2   4.5 |  -7.5  18.5  015  23 12   7.7   4.2
  8500  -5.4  22.3  005  21 11   9.8   5.4 |  -6.9  19.6  015  22 11   9.4   5.2
  8250  -4.7  23.5  005  20 10   9.4   5.1 |  -6.2  20.8  010  21 11   9.1   5.0
  8000  -4.0  24.8  010  19 10  10.1   5.5 |  -5.5  22.1  010  20 10   9.1   5.0
  7750  -3.2  26.2  010  18  9   9.5   5.2 |  -4.9  23.2  010  18  9   8.5   4.7
  7500  -2.6  27.3  010  17  9   8.6   4.7 |  -4.3  24.3  010  16  8   8.5   4.6
  7250  -2.0  28.4  010  15  8   7.4   4.0 |  -3.7  25.3  010  14  7   6.6   3.6
  7000  -1.6  29.1  010  14  7   4.0   2.2 |  -3.4  25.9  010  13  7   1.9   1.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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