Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 131204
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0604 MDT Wednesday, March 13, 2024

This forecast is for the Air Force Academy for Wednesday, March 13, 2024:

If the trigger temperature of 42.5 F/5.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 349 ft/min (1.8 m/s)
   Maximum height of thermals.................. 15960 ft MSL (8351 ft AGL)

Forecast maximum temperature................... 50.0 F/10.5 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12443 ft MSL (4834 ft AGL)
Thermal soaring outlook for Thursday 03/14..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:12:20 / 19:04:41 MDT
Total possible sunshine........... 11 hr 52 min 21 sec (712 min 21 sec)
Altitude of sun at 13:08:30 MDT... 48.47 degrees

Upper air data from numerical model forecast valid on 03/13/2024 at 0600 MDT

Freezing level.................. 7801 ft MSL (192 ft AGL)
Additional freezing level....... 8154 ft MSL (545 ft AGL)
Convective condensation level... 13345 ft MSL (5736 ft AGL)
Lifted condensation level....... 14247 ft MSL (6638 ft AGL)
Lifted index.................... -1.2
K index......................... +16.0

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -55.2 -67.4   255   28   14   1.6   0.9      M     M       M      M    M
 45000  -52.7 -62.9   240   26   13   1.6   0.9      M     M       M      M    M
 40000  -52.8 -63.0   225   50   26  -0.2  -0.1      M     M       M      M    M
 38000  -53.1 -63.6   220   58   30  -2.0  -1.1      M     M       M      M    M
 36000  -54.2 -65.6   220   52   27  -1.9  -1.0      M     M       M      M    M
 34000  -55.3 -67.5   220   47   24  -2.2  -1.2      M     M       M      M    M
 32000  -52.9 -63.2   220   43   22   4.7   2.6      M     M       M      M    M
 30000  -50.1 -58.2   220   40   20   6.5   3.6      M     M       M      M    M
 29000  -47.5 -53.5   220   37   19   9.0   5.0   17.3  63.1     5.7      M    M
 28000  -44.8 -48.6   220   34   17   9.0   5.0   17.0  62.6     5.5      M    M
 27000  -42.1 -43.8   220   31   16   9.0   5.0   16.8  62.3     5.4      M    M
 26000  -39.5 -39.1   220   29   15   8.3   4.6   16.4  61.5     5.2      M    M
 25000  -37.0 -34.6   225   28   14   8.3   4.6   15.8  60.5     4.7      M    M
 24000  -34.5 -30.1   230   27   14   8.3   4.6   15.3  59.6     4.4      M    M
 23000  -32.0 -25.6   240   27   14   8.4   4.6   14.8  58.7     4.0      M    M
 22000  -29.5 -21.1   245   27   14   8.4   4.6   14.3  57.8     3.6      M    M
 21000  -27.0 -16.6   250   27   14   8.4   4.6   13.9  57.0     3.3      M    M
 20000  -24.0 -11.2   255   25   13   8.1   4.5   13.2  55.7     2.7      M    M
 19500  -22.8  -9.0   255   25   13   8.1   4.5   12.9  55.2     2.4      M    M
 19000  -21.6  -6.9   255   24   12   8.2   4.5   12.6  54.8     2.2      M    M
 18500  -20.4  -4.7   260   23   12   8.2   4.5   12.4  54.4     2.0      M    M
 18000  -19.3  -2.7   260   22   11   7.2   4.0   12.1  53.7     1.7      M    M
 17500  -18.2  -0.8   265   20   11   7.3   4.0   11.7  53.0     1.3      M    M
 17000  -17.1   1.2   265   19   10   6.8   3.7   11.2  52.2     0.9      M    M
 16500  -16.1   3.0   275   18   10   6.7   3.7   10.7  51.3     0.5      M    M
 16000  -15.2   4.6   280   18    9   6.9   3.8   10.2  50.4    -0.0    749  3.8
 15500  -14.1   6.6   290   18    9   7.6   4.2    9.8  49.7    -0.4    702  3.6
 15000  -13.0   8.6   300   18    9   7.6   4.2    9.5  49.1    -0.7    654  3.3
 14500  -11.9  10.6   305   17    9   7.3   4.0    9.1  48.4    -1.1    606  3.1
 14000  -10.8  12.6   310   16    8   7.3   4.0    8.7  47.7    -1.5    559  2.8
 13500   -9.7  14.5   310   16    8   8.1   4.4    8.4  47.1    -1.9    511  2.6
 13000   -8.5  16.7   310   16    8   9.0   4.9    8.1  46.6    -2.2    462  2.3
 12500   -7.8  18.0   310   16    8   3.3   1.8    7.4  45.3    -2.9    425  2.2
 12000   -6.9  19.6   310   16    8   5.8   3.2    6.8  44.2    -3.5    384  1.9
 11750   -6.5  20.3   310   15    8   6.4   3.5    6.5  43.7    -3.8    363  1.8
 11500   -6.0  21.2   315   16    8   5.9   3.3    6.3  43.3    -4.1    342  1.7
 11250   -5.6  21.9   320   15    8   5.1   2.8    5.9  42.6    -4.4    323  1.6
 11000   -5.2  22.6   325   15    8   5.0   2.7    5.5  42.0    -4.8    304  1.5
 10750   -4.9  23.2   330   15    8   5.1   2.8    5.2  41.3    -5.2    286  1.5
 10500   -4.5  23.9   335   16    8   5.1   2.8    4.8  40.7    -5.5    267  1.4
 10250   -4.1  24.6   340   17    9   5.5   3.0    4.5  40.1    -5.9    248  1.3
 10000   -3.7  25.3   345   17    9   5.8   3.2    4.2  39.5    -6.2    228  1.2
  9750   -3.3  26.1   350   18    9   5.9   3.2    3.9  38.9    -6.5    208  1.1
  9500   -2.8  27.0   350   19   10   6.3   3.5    3.6  38.5    -6.8    187  1.0
  9250   -2.4  27.7   350   19   10   6.4   3.5    3.3  38.0    -7.1    166  0.8
  9000   -1.9  28.6   350   20   10   6.4   3.5    3.1  37.5    -7.4    145  0.7
  8750   -1.4  29.5   350   20   11   6.7   3.7    2.8  37.1    -7.7    123  0.6
  8500   -0.9  30.4   350   20   10   6.7   3.7    2.6  36.7    -7.9    101  0.5
  8250   -0.4  31.3   350   20   10   7.4   4.1    2.4  36.3    -8.2     78  0.4
  8000    0.1  32.2   350   20   10   5.4   3.0    2.2  35.9    -8.4     55  0.3
  7750    0.2  32.4   345   16    8  -4.7  -2.6    1.5  34.8    -9.1     46  0.2
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  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 * * * * * *

           03/13/2024 at 0900 MDT          |       03/13/2024 at 1200 MDT
                                           |
CAPE...    +0.8    LI...       +1.0        | CAPE...   +65.4    LI...       +0.1
CINH...     0.0    K Index... +16.1        | CINH...   -32.1    K Index... +17.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -54.3 -65.7  250  27 14   1.3   0.7 | -54.0 -65.2  245  24 13   1.5   0.8
 45000 -52.2 -62.0  245  37 19   1.3   0.7 | -51.7 -61.1  235  36 18   1.4   0.8
 40000 -52.1 -61.8  235  46 24  -0.0  -0.0 | -51.3 -60.3  235  39 20   0.2   0.1
 38000 -52.3 -62.1  230  49 25  -2.4  -1.3 | -51.3 -60.3  235  39 20  -2.0  -1.1
 36000 -53.6 -64.5  225  44 23  -2.2  -1.2 | -52.4 -62.3  235  38 19  -1.8  -1.0
 34000 -54.9 -66.8  220  41 21  -2.0  -1.1 | -53.6 -64.5  235  36 18  -2.1  -1.1
 32000 -53.5 -64.3  215  35 18   3.2   1.7 | -53.1 -63.6  225  32 16   1.2   0.6
 30000 -51.7 -61.1  210  30 15   4.3   2.3 | -52.4 -62.3  215  28 14   1.4   0.8
 29000 -49.1 -56.4  215  29 15   9.2   5.1 | -50.2 -58.4  215  27 14   9.1   5.0
 28000 -46.4 -51.5  215  29 15   9.2   5.0 | -47.5 -53.5  215  27 14   9.1   5.0
 27000 -43.6 -46.5  220  30 15   9.2   5.0 | -44.7 -48.5  215  26 14   9.1   5.0
 26000 -41.0 -41.8  225  29 15   8.3   4.6 | -42.1 -43.8  220  25 13   9.0   4.9
 25000 -38.5 -37.3  230  28 14   8.3   4.6 | -39.4 -38.9  225  23 12   9.0   4.9
 24000 -36.1 -33.0  235  27 14   8.3   4.6 | -36.7 -34.1  230  21 11   9.0   4.9
 23000 -33.6 -28.5  240  25 13   8.7   4.7 | -34.0 -29.2  240  19 10   8.9   4.9
 22000 -31.0 -23.8  245  23 12   8.6   4.7 | -31.4 -24.5  240  17  9   8.9   4.9
 21000 -28.4 -19.1  250  20 11   8.6   4.7 | -28.7 -19.7  245  15  8   9.0   4.9
 20000 -25.2 -13.4  255  18  9   8.7   4.8 | -25.7 -14.3  255  13  7   8.0   4.4
 19500 -23.9 -11.0  255  17  9   8.7   4.8 | -24.5 -12.1  260  12  6   8.0   4.4
 19000 -22.6  -8.7  260  16  8   8.7   4.8 | -23.3  -9.9  265  12  6   8.0   4.4
 18500 -21.3  -6.3  260  15  8   8.8   4.8 | -22.1  -7.8  270  11  6   8.0   4.4
 18000 -20.1  -4.2  260  13  7   7.5   4.1 | -20.9  -5.6  270  10  5   8.5   4.7
 17500 -19.0  -2.2  255  11  6   7.6   4.2 | -19.6  -3.3  265   8  4   8.5   4.7
 17000 -17.9  -0.2  255  10  5   7.8   4.3 | -18.4  -1.1  260   7  3   7.5   4.1
 16500 -16.7   1.9  255   9  5   7.9   4.3 | -17.4   0.7  255   6  3   7.0   3.8
 16000 -15.5   4.1  255   8  4   7.6   4.1 | -16.4   2.5  245   5  3   7.2   3.9
 15500 -14.5   5.9  265   7  3   6.6   3.6 | -15.2   4.6  245   4  2   8.0   4.4
 15000 -13.5   7.7  285   6  3   6.6   3.6 | -14.0   6.8  255   3  1   8.0   4.4
 14500 -12.5   9.5  305   6  3   7.3   4.0 | -12.8   9.0  280   2  1   8.4   4.6
 14000 -11.4  11.5  315   8  4   7.2   4.0 | -11.6  11.1  310   3  1   8.3   4.6
 13500 -10.3  13.5  320   9  5   8.1   4.5 | -10.3  13.5  325   4  2   8.8   4.8
 13000  -9.2  15.4  325  11  5   9.2   5.0 |  -9.0  15.8  330   5  3   9.6   5.3
 12500  -8.5  16.7  325  12  6   2.5   1.4 |  -8.1  17.4  330   7  4   4.7   2.6
 12000  -7.7  18.1  325  13  7   5.3   2.9 |  -7.0  19.4  330   8  4   7.0   3.8
 11750  -7.3  18.9  325  14  7   6.1   3.4 |  -6.5  20.3  330   9  5   7.9   4.3
 11500  -6.8  19.8  325  14  7   6.0   3.3 |  -5.9  21.4  330  10  5   7.2   4.0
 11250  -6.4  20.5  325  15  8   4.8   2.6 |  -5.5  22.1  325  10  5   5.5   3.0
 11000  -6.1  21.0  330  15  8   4.6   2.5 |  -5.1  22.8  325  10  5   5.4   3.0
 10750  -5.8  21.6  330  15  8   4.7   2.6 |  -4.7  23.5  325  11  6   5.2   2.9
 10500  -5.4  22.3  335  15  8   4.5   2.4 |  -4.4  24.1  325  11  6   4.4   2.4
 10250  -5.1  22.8  335  16  8   5.3   2.9 |  -4.1  24.6  325  12  6   4.4   2.4
 10000  -4.7  23.5  340  16  8   6.3   3.4 |  -3.8  25.2  320  12  6   4.7   2.6
  9750  -4.2  24.4  340  16  8   5.7   3.1 |  -3.4  25.9  320  13  7   4.9   2.7
  9500  -3.8  25.2  345  17  9   5.1   2.8 |  -3.1  26.4  325  13  7   5.0   2.7
  9250  -3.5  25.7  345  18  9   5.5   3.0 |  -2.7  27.1  325  13  7   5.9   3.2
  9000  -3.0  26.6  350  19 10   6.6   3.6 |  -2.3  27.9  330  13  7   7.4   4.0
  8750  -2.5  27.5  350  20 10   7.4   4.0 |  -1.7  28.9  335  14  7   9.4   5.2
  8500  -2.0  28.4  350  19 10   7.8   4.3 |  -0.9  30.4  340  13  7  11.0   6.0
  8250  -1.4  29.5  350  19 10   7.2   4.0 |  -0.1  31.8  340  13  7  10.2   5.6
  8000  -0.9  30.4  345  18  9  10.1   5.6 |   0.6  33.1  340  13  7  12.1   6.6
  7750   0.2  32.4  345  15  8  17.8   9.8 |   1.8  35.2  340  12  6  21.6  11.8
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    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     M     M

           03/13/2024 at 1500 MDT          |       03/13/2024 at 1800 MDT
                                           |
CAPE...  +148.8    LI...       -0.3        | CAPE...   +32.9    LI...       -0.1
CINH...    -0.5    K Index... +18.9        | CINH...    -8.6    K Index... +21.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -53.9 -65.0  240  26 13   1.9   1.0 | -52.9 -63.2  255  24 12   0.9   0.5
 45000 -50.9 -59.6  235  34 18   1.9   1.0 | -51.5 -60.7  245  29 15   0.9   0.5
 40000 -51.0 -59.8  240  33 17  -0.3  -0.2 | -50.8 -59.4  245  30 16   0.4   0.2
 38000 -51.3 -60.3  245  33 17  -2.6  -1.4 | -50.9 -59.6  240  30 16  -3.8  -2.1
 36000 -52.8 -63.0  240  33 17  -2.3  -1.3 | -53.0 -63.4  240  28 14  -3.5  -1.9
 34000 -54.3 -65.7  240  34 17  -2.8  -1.6 | -55.1 -67.2  235  26 13  -3.5  -1.9
 32000 -53.2 -63.8  235  30 15   2.6   1.4 | -54.3 -65.7  235  18  9   2.8   1.5
 30000 -51.7 -61.1  230  24 13   2.8   1.6 | -52.6 -62.7  250   9  5   2.1   1.2
 29000 -49.4 -56.9  230  23 12   9.0   4.9 | -50.3 -58.5  250   9  4   9.7   5.3
 28000 -46.7 -52.1  235  22 11   9.0   4.9 | -47.4 -53.3  250  10  5   9.7   5.3
 27000 -44.0 -47.2  240  21 11   9.0   4.9 | -43.7 -46.7  250  11  6   9.7   5.3
 26000 -41.3 -42.3  245  20 10   9.0   4.9 | -40.9 -41.6  250  11  6   9.1   5.0
 25000 -38.6 -37.5  250  19 10   9.0   4.9 | -38.2 -36.8  250  10  5   9.1   5.0
 24000 -36.0 -32.8  255  18  9   9.0   4.9 | -35.5 -31.9  250  10  5   9.1   5.0
 23000 -33.3 -27.9  260  17  9   8.9   4.9 | -32.8 -27.0  250   9  5   8.6   4.7
 22000 -30.6 -23.1  260  16  8   8.9   4.9 | -30.2 -22.4  250   8  4   8.6   4.7
 21000 -28.0 -18.4  260  15  8   8.9   4.9 | -27.7 -17.9  250   8  4   8.7   4.8
 20000 -24.9 -12.8  260  13  7   7.9   4.3 | -25.2 -13.4  250   7  3   8.3   4.5
 19500 -23.8 -10.8  260  12  6   7.9   4.3 | -23.9 -11.0  250   6  3   8.3   4.5
 19000 -22.6  -8.7  265  11  6   7.9   4.3 | -22.7  -8.9  250   6  3   8.3   4.6
 18500 -21.4  -6.5  265  10  5   8.0   4.4 | -21.5  -6.7  245   5  3   8.3   4.6
 18000 -20.3  -4.5  265  10  5   7.2   3.9 | -20.3  -4.5  245   5  2   7.9   4.3
 17500 -19.3  -2.7  265   9  4   7.2   4.0 | -19.1  -2.4  235   4  2   7.9   4.3
 17000 -18.2  -0.8  270   8  4   7.1   3.9 | -17.9  -0.2  225   4  2   7.8   4.3
 16500 -17.2   1.0  270   7  3   7.1   3.9 | -16.8   1.8  210   3  2   7.6   4.2
 16000 -16.1   3.0  270   5  3   7.0   3.9 | -15.7   3.7  190   4  2   7.6   4.2
 15500 -15.1   4.8  275   5  2   6.6   3.6 | -14.6   5.7  175   4  2   6.7   3.7
 15000 -14.2   6.4  280   4  2   6.6   3.6 | -13.6   7.5  160   5  3   6.8   3.7
 14500 -13.2   8.2  290   3  2   6.8   3.7 | -12.6   9.3  155   6  3   6.7   3.7
 14000 -12.2  10.0  305   3  1   6.7   3.7 | -11.7  10.9  145   7  4   6.7   3.7
 13500 -11.1  12.0  325   3  1   7.9   4.3 | -10.6  12.9  140   8  4   8.2   4.5
 13000 -10.0  14.0  340   3  2   9.0   4.9 |  -9.4  15.1  130   8  4   9.8   5.4
 12500  -9.2  15.4  355   4  2   4.1   2.2 |  -8.7  16.3  125   9  5   2.7   1.5
 12000  -8.1  17.4  010   5  3   6.9   3.8 |  -7.7  18.1  115   9  5   6.3   3.4
 11750  -7.6  18.3  015   5  3   7.5   4.1 |  -7.2  19.0  115   9  5   7.4   4.1
 11500  -7.1  19.2  020   6  3   7.7   4.2 |  -6.6  20.1  110   9  5   9.4   5.1
 11250  -6.5  20.3  025   7  4   7.3   4.0 |  -6.0  21.2  105  10  5   7.4   4.1
 11000  -6.0  21.2  035   8  4   7.2   3.9 |  -5.6  21.9  100  10  5   5.2   2.8
 10750  -5.5  22.1  035   9  5   7.4   4.0 |  -5.2  22.6  100  10  5   5.7   3.1
 10500  -5.0  23.0  040  10  5   7.9   4.3 |  -4.7  23.5  095  10  5   7.1   3.9
 10250  -4.4  24.1  040  11  6   8.7   4.8 |  -4.2  24.4  090  10  5   7.4   4.0
 10000  -3.7  25.3  040  11  6   9.0   4.9 |  -3.7  25.3  085  10  5   6.3   3.4
  9750  -3.1  26.4  040  12  6   9.1   5.0 |  -3.2  26.2  085  10  5   6.5   3.6
  9500  -2.4  27.7  040  12  6   9.7   5.3 |  -2.8  27.0  085  10  5   6.4   3.5
  9250  -1.7  28.9  040  12  6   9.6   5.3 |  -2.3  27.9  080   9  5   6.1   3.3
  9000  -1.0  30.2  040  12  6   8.6   4.7 |  -1.9  28.6  080   9  5   5.5   3.0
  8750  -0.4  31.3  040  12  6   9.1   5.0 |  -1.1  30.0  075   8  4   5.3   2.9
  8500   0.3  32.5  040  12  6  10.0   5.5 |  -0.7  30.7  075   7  4   5.3   2.9
  8250   1.1  34.0  040  11  6   9.9   5.4 |  -0.4  31.3  075   7  3   5.9   3.2
  8000   1.8  35.2  040  11  6   9.3   5.1 |   0.1  32.2  075   5  3   6.7   3.7
  7750   2.5  36.5  040  10  5  11.8   6.5 |   0.5  32.9  060   4  2   4.0   2.2
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    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     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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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