Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 231014
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0413 MDT Monday, March 23, 2015

This forecast is for Monday, March 23, 2015:

If the trigger temperature of 51.4 F/10.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 913 ft/min (4.6 m/s)
   Maximum height of thermals.................. 16843 ft MSL (10085 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1115 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................. 11742 ft MSL (4985 ft AGL)
Thermal soaring outlook for Tuesday 03/24...... Good

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

Remarks...

Sunrise/Sunset.................... 06:58:01 / 19:12:44 MDT
Total possible sunshine........... 12 hr 14 min 43 sec (734 min 43 sec)
Altitude of sun at 13:05:32 MDT... 52.19 degrees

Upper air data from numerical model forecast valid on 03/23/2015 at 0600 MDT

Freezing level.................. 10761 ft MSL (4003 ft AGL)
Convective condensation level... 14989 ft MSL (8231 ft AGL)
Lifted condensation level....... 15015 ft MSL (8258 ft AGL)
Lifted index.................... +0.3
K index......................... +14.5

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  -59.5 -75.1   270   40   20   1.6   0.9      M     M       M      M    M
 45000  -57.0 -70.6   265   42   22  -1.4  -0.8      M     M       M      M    M
 40000  -61.6 -78.9   265   74   38  -3.1  -1.7      M     M       M      M    M
 38000  -60.6 -77.1   265   76   39   6.0   3.3      M     M       M      M    M
 36000  -57.0 -70.6   265   69   35   6.0   3.3      M     M       M      M    M
 34000  -53.1 -63.6   260   62   32   7.7   4.2      M     M       M      M    M
 32000  -48.0 -54.4   260   57   29   7.6   4.2      M     M       M      M    M
 30000  -43.3 -45.9   260   53   27   8.0   4.4   26.3  79.3     8.2      M    M
 29000  -40.9 -41.6   265   52   27   8.0   4.4   25.5  77.9     7.7      M    M
 28000  -38.6 -37.5   265   50   26   8.0   4.4   24.9  76.8     7.3      M    M
 27000  -36.1 -33.0   270   49   25   8.9   4.9   24.4  75.8     7.0      M    M
 26000  -33.4 -28.1   270   48   25   8.9   4.9   23.9  75.1     6.7      M    M
 25000  -30.8 -23.4   270   47   24   8.9   4.9   23.7  74.6     6.6      M    M
 24000  -28.2 -18.8   275   46   24   7.4   4.1   23.4  74.1     6.4      M    M
 23000  -26.2 -15.2   270   44   22   6.7   3.7   22.2  72.0     5.5      M    M
 22000  -24.2 -11.6   270   41   21   6.7   3.7   21.1  70.1     4.6      M    M
 21000  -22.2  -8.0   265   38   20   6.6   3.6   20.1  68.2     3.8      M    M
 20000  -20.2  -4.4   265   36   18   6.6   3.6   19.0  66.1     2.8      M    M
 19500  -19.2  -2.6   265   34   18   6.6   3.6   18.4  65.2     2.4      M    M
 19000  -18.2  -0.8   265   33   17   6.6   3.6   17.9  64.2     1.9      M    M
 18500  -17.2   1.0   265   32   16   6.8   3.8   17.4  63.4     1.5      M    M
 18000  -16.2   2.8   260   31   16   6.9   3.8   16.9  62.5     1.1      M    M
 17500  -15.2   4.6   260   29   15   7.0   3.9   16.5  61.6     0.6      M    M
 17000  -14.1   6.6   260   28   14   7.2   4.0   16.0  60.8     0.2      M    M
 16500  -13.1   8.4   260   26   13   7.1   3.9   15.6  60.1    -0.2    890  4.5
 16000  -11.9  10.6   260   25   13   9.2   5.0   15.3  59.6    -0.5    840  4.3
 15500   -9.9  14.2   255   23   12   9.1   5.0   15.2  59.3    -0.7    758  3.8
 15000   -8.5  16.7   255   22   11   9.1   5.0   15.0  59.1    -0.8    703  3.6
 14500   -7.2  19.0   250   20   10   9.2   5.1   14.9  58.9    -0.9    648  3.3
 14000   -6.0  21.2   245   19   10   7.9   4.4   14.7  58.5    -1.1    596  3.0
 13500   -4.8  23.4   240   19   10   8.1   4.5   14.5  58.1    -1.4    545  2.8
 13000   -3.6  25.5   235   19   10   7.0   3.9   14.1  57.5    -1.8    497  2.5
 12500   -2.6  27.3   230   18    9   7.1   3.9   13.7  56.7    -2.2    451  2.3
 12000   -1.7  28.9   220   18    9   5.4   3.0   13.2  55.7    -2.7    408  2.1
 11750   -1.3  29.7   220   18    9   5.5   3.0   12.8  55.1    -3.1    389  2.0
 11500   -0.9  30.4   215   18    9   5.8   3.2   12.5  54.5    -3.4    369  1.9
 11250   -0.5  31.1   210   18    9   4.5   2.5   12.2  53.9    -3.7    350  1.8
 11000   -0.2  31.6   205   18    9   3.4   1.9   11.7  53.0    -4.2    335  1.7
 10750    0.1  32.2   200   19   10   3.8   2.1   11.2  52.2    -4.7    319  1.6
 10500    0.3  32.5   195   19   10   3.9   2.2   10.7  51.3    -5.2    303  1.5
 10250    0.6  33.1   190   20   10   3.1   1.7   10.3  50.5    -5.6    288  1.5
 10000    0.8  33.4   190   21   11   1.4   0.8    9.7  49.4    -6.2    276  1.4
  9750    0.8  33.4   185   21   11   1.2   0.6    9.0  48.2    -6.9    266  1.4
  9500    0.9  33.6   185   22   11   1.1   0.6    8.4  47.1    -7.6    256  1.3
  9250    1.0  33.8   180   23   12   1.4   0.8    7.7  45.9    -8.2    246  1.3
  9000    1.1  34.0   180   23   12   1.5   0.8    7.1  44.7    -8.9    236  1.2
  8750    1.3  34.3   180   23   12   2.6   1.4    6.5  43.6    -9.5    224  1.1
  8500    1.5  34.7   180   23   12   3.8   2.1    6.0  42.8   -10.0    209  1.1
  8250    1.8  35.2   185   22   12   4.1   2.2    5.5  42.0   -10.5    194  1.0
  8000    2.1  35.8   185   21   11   3.6   2.0    5.1  41.2   -11.0    178  0.9
  7750    2.3  36.1   190   20   10   6.6   3.6    4.7  40.5   -11.4    162  0.8
  7500    2.8  37.0   190   18    9   2.2   1.2    4.5  40.0   -11.7    141  0.7
  7250    2.5  36.5   195   15    8  -8.2  -4.5    3.7  38.7   -12.5    144  0.7
  7000    1.8  35.2   195   12    6  -6.2  -3.4    2.8  37.1   -13.4    156  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           03/23/2015 at 0900 MDT          |       03/23/2015 at 1200 MDT
                                           |
K index... +13.3  LI... +275.1             | K index... -1.9  LI... +275.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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 -58.6 -73.5  270  36 19   1.7   1.0 | -57.7 -71.9  265  34 17   2.3   1.3
 45000 -56.0 -68.8  260  49 25  -1.3  -0.7 | -54.2 -65.6  255  54 28  -0.7  -0.4
 40000 -60.7 -77.3  260  67 34  -3.1  -1.7 | -59.9 -75.8  255  70 36  -3.8  -2.1
 38000 -60.2 -76.4  260  70 36   4.6   2.5 | -59.9 -75.8  255  72 37   4.4   2.4
 36000 -57.4 -71.3  260  69 36   4.7   2.6 | -57.2 -71.0  255  68 35   4.4   2.4
 34000 -54.2 -65.6  255  68 35   7.8   4.3 | -54.3 -65.7  255  64 33   7.9   4.3
 32000 -49.6 -57.3  255  62 32   7.7   4.2 | -49.2 -56.6  255  60 31   7.5   4.1
 30000 -44.2 -47.6  255  57 29   9.2   5.0 | -44.6 -48.3  255  56 29   8.3   4.5
 29000 -41.4 -42.5  255  55 28   9.2   5.0 | -42.1 -43.8  255  54 28   8.3   4.5
 28000 -38.7 -37.7  255  53 28   9.2   5.0 | -39.6 -39.3  255  53 27   8.3   4.5
 27000 -36.0 -32.8  255  52 27   8.4   4.6 | -37.1 -34.8  255  51 26   8.1   4.5
 26000 -33.5 -28.3  255  50 26   8.4   4.6 | -34.7 -30.5  255  49 25   8.1   4.4
 25000 -31.0 -23.8  250  48 25   8.4   4.6 | -32.3 -26.1  255  46 24   8.1   4.4
 24000 -28.5 -19.3  250  46 24   7.4   4.0 | -29.8 -21.6  250  44 23   8.4   4.6
 23000 -26.5 -15.7  245  42 22   6.7   3.7 | -27.2 -17.0  255  41 21   8.8   4.8
 22000 -24.5 -12.1  240  39 20   6.7   3.7 | -24.5 -12.1  260  38 19   8.8   4.9
 21000 -22.4  -8.3  240  36 18   7.7   4.2 | -22.0  -7.6  260  35 18   7.4   4.0
 20000 -20.1  -4.2  245  35 18   7.7   4.2 | -19.8  -3.6  260  37 19   7.2   4.0
 19500 -18.9  -2.0  245  34 18   7.7   4.2 | -18.7  -1.7  260  38 20   7.2   4.0
 19000 -17.8  -0.0  250  34 17   7.8   4.3 | -17.7   0.1  260  39 20   7.2   4.0
 18500 -16.7   1.9  250  33 17   5.4   2.9 | -16.6   2.1  260  40 20   7.0   3.8
 18000 -16.1   3.0  250  31 16   4.7   2.6 | -15.6   3.9  260  38 20   6.8   3.7
 17500 -15.4   4.3  250  30 15   5.1   2.8 | -14.5   5.9  260  37 19   6.8   3.7
 17000 -14.5   5.9  250  29 15   6.9   3.8 | -13.5   7.7  260  37 19   6.6   3.6
 16500 -13.5   7.7  250  28 15   6.7   3.7 | -12.5   9.5  260  37 19   6.6   3.6
 16000 -12.5   9.5  250  27 14   8.6   4.7 | -11.5  11.3  255  36 19   6.6   3.6
 15500 -11.2  11.8  250  26 13   8.6   4.7 | -10.1  13.8  255  35 18   6.6   3.6
 15000  -9.3  15.3  250  24 12   9.2   5.0 |  -9.1  15.6  255  34 17   7.1   3.9
 14500  -7.9  17.8  255  23 12   9.1   5.0 |  -8.0  17.6  255  33 17   7.1   3.9
 14000  -6.5  20.3  255  23 12   9.9   5.5 |  -7.0  19.4  255  31 16   7.8   4.3
 13500  -5.0  23.0  255  22 11  10.0   5.5 |  -5.9  21.4  250  30 15   7.8   4.3
 13000  -3.5  25.7  250  22 11   9.2   5.0 |  -4.7  23.5  250  28 14   9.1   5.0
 12500  -2.2  28.0  250  22 11   9.2   5.1 |  -3.3  26.1  250  27 14   9.9   5.4
 12000  -0.9  30.4  250  22 12   7.1   3.9 |  -2.3  27.9  250  25 13   6.4   3.5
 11750  -0.4  31.3  245  22 12   6.4   3.5 |  -1.6  29.1  250  24 13   9.0   4.9
 11500   0.1  32.2  245  22 11   7.3   4.0 |  -1.0  30.2  250  24 12   8.2   4.5
 11250   0.6  33.1  240  22 11   4.3   2.4 |  -0.4  31.3  250  23 12   8.7   4.8
 11000   0.7  33.3  240  22 11   1.7   0.9 |   0.2  32.4  250  22 11   8.1   4.5
 10750   0.9  33.6  235  21 11   2.5   1.4 |   0.8  33.4  250  22 11   7.4   4.1
 10500   1.0  33.8  230  21 11   2.9   1.6 |   1.3  34.3  245  21 11   8.1   4.4
 10250   1.2  34.2  230  21 11   0.8   0.4 |   1.9  35.4  245  20 10   6.2   3.4
 10000   1.1  34.0  220  20 10  -3.2  -1.8 |   2.2  36.0  245  20 10   1.1   0.6
  9750   0.8  33.4  215  20 10  -2.4  -1.3 |   2.2  36.0  240  18  9   1.1   0.6
  9500   0.7  33.3  210  20 10  -1.3  -0.7 |   2.3  36.1  235  17  9   3.5   1.9
  9250   0.5  32.9  200  21 11  -1.0  -0.5 |   2.5  36.5  225  16  8   1.5   0.8
  9000   0.5  32.9  200  21 11  -0.0  -0.0 |   2.4  36.3  220  15  8  -3.2  -1.7
  8750   0.5  32.9  195  21 11   0.3   0.1 |   2.3  36.1  210  15  8   3.4   1.9
  8500   0.5  32.9  190  22 11   0.2   0.1 |   2.9  37.2  200  15  8   9.9   5.4
  8250   0.6  33.1  190  22 11   4.1   2.3 |   3.5  38.3  190  15  8   8.9   4.9
  8000   1.1  34.0  190  21 11   7.4   4.1 |   4.3  39.7  190  14  7  10.6   5.8
  7750   1.6  34.9  190  19 10   6.5   3.6 |   5.0  41.0  190  14  7   9.2   5.0
  7500   2.1  35.8  190  17  9   7.2   3.9 |   5.7  42.3  185  14  7   8.8   4.8
  7250   2.6  36.7  190  16  8   7.7   4.2 |   6.4  43.5  185  14  7  12.2   6.7
  7000   3.2  37.8  190  15  8   7.9   4.3 |   7.5  45.5  185  13  7  15.2   8.4
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/23/2015 at 1500 MDT          |       03/23/2015 at 1800 MDT
                                           |
K index... +6.7  LI... +273.7              | K index... +1.5  LI... +274.3
CAPE... +7.3  CIN... -4.0                  | CAPE... +4.2  CIN... -32.8
                                           |
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 -57.8 -72.0  265  35 18   2.4   1.3 | -57.9 -72.2  265  32 16   2.6   1.4
 45000 -54.0 -65.2  265  59 30   0.3   0.2 | -53.9 -65.0  265  52 27   0.9   0.5
 40000 -57.8 -72.0  255  69 35  -2.5  -1.4 | -56.8 -70.2  260  63 32  -1.9  -1.1
 38000 -57.9 -72.2  255  71 36   2.5   1.4 | -57.1 -70.8  260  67 34   1.4   0.7
 36000 -56.5 -69.7  255  69 36   2.5   1.4 | -56.3 -69.3  260  70 36   1.3   0.7
 34000 -54.7 -66.5  260  68 35   7.1   3.9 | -55.2 -67.4  260  73 37   6.3   3.4
 32000 -49.9 -57.8  260  69 36   7.1   3.9 | -51.1 -60.0  265  71 37   6.9   3.8
 30000 -45.5 -49.9  260  69 36   8.4   4.6 | -46.3 -51.3  265  69 36   7.7   4.2
 29000 -43.0 -45.4  260  68 35   8.4   4.6 | -44.0 -47.2  265  67 34   7.7   4.2
 28000 -40.4 -40.7  265  66 34   8.4   4.6 | -41.7 -43.1  265  64 33   7.7   4.2
 27000 -37.9 -36.2  265  65 33   8.1   4.4 | -39.3 -38.7  270  62 32   8.0   4.4
 26000 -35.6 -32.1  265  61 31   7.8   4.3 | -36.9 -34.4  270  58 30   8.3   4.6
 25000 -33.2 -27.8  270  57 29   7.8   4.3 | -34.4 -29.9  270  55 28   8.3   4.6
 24000 -30.9 -23.6  275  53 27   8.1   4.5 | -31.9 -25.4  270  52 27   8.5   4.6
 23000 -28.3 -18.9  275  50 26   8.6   4.7 | -29.3 -20.7  270  49 25   8.8   4.8
 22000 -25.7 -14.3  275  48 25   8.6   4.7 | -26.6 -15.9  270  47 24   8.8   4.8
 21000 -23.1  -9.6  270  46 24   8.1   4.5 | -24.0 -11.2  270  44 23   8.8   4.8
 20000 -20.7  -5.3  270  44 23   8.0   4.4 | -21.3  -6.3  270  41 21   8.8   4.9
 19500 -19.5  -3.1  270  44 22   8.0   4.4 | -20.0  -4.0  270  39 20   8.9   4.9
 19000 -18.3  -0.9  270  43 22   8.0   4.4 | -18.6  -1.5  265  37 19   8.8   4.8
 18500 -17.1   1.2  270  42 22   7.4   4.1 | -17.3   0.9  265  36 18   8.4   4.6
 18000 -16.1   3.0  270  44 23   7.0   3.8 | -16.1   3.0  265  37 19   8.1   4.4
 17500 -15.1   4.8  270  45 23   7.0   3.8 | -14.9   5.2  265  38 19   8.1   4.4
 17000 -14.1   6.6  275  45 23   7.0   3.8 | -13.8   7.2  270  38 20   6.5   3.5
 16500 -13.0   8.6  275  45 23   7.0   3.8 | -12.9   8.8  270  38 20   6.6   3.6
 16000 -12.0  10.4  275  43 22   7.1   3.9 | -11.9  10.6  270  38 20   7.1   3.9
 15500 -10.5  13.1  275  39 20   7.0   3.9 | -10.8  12.6  270  36 19   7.4   4.0
 15000  -9.3  15.3  270  36 18   9.0   4.9 |  -9.1  15.6  270  33 17   9.3   5.1
 14500  -8.0  17.6  270  33 17   8.9   4.9 |  -7.8  18.0  265  31 16   9.1   5.0
 14000  -6.7  19.9  270  30 16   9.2   5.0 |  -6.4  20.5  265  30 15   9.7   5.3
 13500  -5.4  22.3  270  29 15   9.2   5.1 |  -4.9  23.2  265  28 15   9.8   5.4
 13000  -4.0  24.8  270  28 14   9.6   5.2 |  -3.5  25.7  265  27 14   9.9   5.4
 12500  -2.5  27.5  265  27 14   9.7   5.3 |  -2.0  28.4  265  26 14   9.8   5.4
 12000  -1.1  30.0  265  27 14   8.9   4.9 |  -0.6  30.9  265  26 13   9.4   5.1
 11750  -0.5  31.1  265  26 13   8.2   4.5 |   0.1  32.2  265  25 13   9.5   5.2
 11500   0.2  32.4  265  25 13   7.7   4.2 |   0.8  33.4  265  25 13   9.4   5.2
 11250   0.8  33.4  265  25 13  10.4   5.7 |   1.5  34.7  265  25 13   9.7   5.3
 11000   1.6  34.9  265  24 12  10.4   5.7 |   2.3  36.1  265  25 13   9.9   5.4
 10750   2.2  36.0  260  23 12   7.6   4.2 |   3.0  37.4  265  24 12   9.6   5.3
 10500   2.8  37.0  260  22 11   8.7   4.8 |   3.7  38.7  265  23 12   9.8   5.4
 10250   3.4  38.1  255  21 11   7.2   4.0 |   4.4  39.9  265  23 12   9.2   5.0
 10000   3.9  39.0  250  19 10   6.7   3.7 |   5.1  41.2  260  22 11   8.6   4.7
  9750   4.5  40.1  245  18  9   9.1   5.0 |   5.8  42.4  260  21 11   9.6   5.3
  9500   5.2  41.4  245  17  9  10.1   5.6 |   6.5  43.7  260  20 10  10.2   5.6
  9250   6.0  42.8  240  16  8   9.7   5.3 |   7.2  45.0  260  19 10   9.9   5.4
  9000   6.7  44.1  235  15  8   9.2   5.0 |   8.0  46.4  255  19 10   9.0   4.9
  8750   7.3  45.1  235  15  8   9.9   5.4 |   8.6  47.5  255  18  9   9.2   5.1
  8500   8.1  46.6  230  15  7  10.8   5.9 |   9.3  48.7  255  17  9  10.0   5.5
  8250   8.9  48.0  230  14  7  10.5   5.7 |  10.1  50.2  250  17  9   9.6   5.3
  8000   9.7  49.5  230  14  7  10.6   5.8 |  10.8  51.4  250  16  8   9.5   5.2
  7750  10.5  50.9  225  14  7   9.9   5.4 |  11.4  52.5  250  15  8   8.8   4.8
  7500  11.2  52.2  225  13  7   8.4   4.6 |  12.1  53.8  245  14  7   9.0   5.0
  7250  11.8  53.2  220  12  6  10.9   6.0 |  12.7  54.9  245  12  6   6.7   3.7
  7000  12.8  55.0  220  12  6  16.0   8.8 |  13.0  55.4  245  11  6   1.0   0.5
  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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