Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 241213
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0612 MDT Sunday, March 24, 2024

This forecast is for the Air Force Academy for Sunday, March 24, 2024:

If the trigger temperature of 44.0 F/6.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1102 ft/min (5.6 m/s)
   Maximum height of thermals.................. 20074 ft MSL (12445 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 0915 MDT
Time of overdevelopment........................ 1100 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14253 ft MSL (6624 ft AGL)
Thermal soaring outlook for Monday 03/25....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:55:02 / 19:15:32 MDT
Total possible sunshine........... 12 hr 20 min 30 sec (740 min 30 sec)
Altitude of sun at 13:05:17 MDT... 52.84 degrees

Upper air data from numerical model forecast valid on 03/24/2024 at 0600 MDT

Freezing level.................. 7750 ft MSL (121 ft AGL)
Additional freezing level....... 9384 ft MSL (1755 ft AGL)
Convective condensation level... 14843 ft MSL (7214 ft AGL)
Lifted condensation level....... 15991 ft MSL (8362 ft AGL)
Lifted index.................... -2.9
K index......................... +8.1

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  -54.8 -66.6   245   45   23   0.9   0.5      M     M       M      M    M
 45000  -53.4 -64.1   240   58   30   0.9   0.5      M     M       M      M    M
 40000  -53.7 -64.7   245   67   34  -0.4  -0.2      M     M       M      M    M
 38000  -54.0 -65.2   245   70   36  -0.9  -0.5      M     M       M      M    M
 36000  -54.7 -66.5   240   64   33  -1.2  -0.6      M     M       M      M    M
 34000  -55.4 -67.7   235   59   30  -1.3  -0.7      M     M       M      M    M
 32000  -53.4 -64.1   230   53   27   4.6   2.5      M     M       M      M    M
 30000  -50.6 -59.1   225   48   25   4.3   2.3      M     M       M      M    M
 29000  -48.3 -54.9   225   48   25   8.9   4.9   16.3  61.3     3.1      M    M
 28000  -45.7 -50.3   220   48   25   8.9   4.9   15.8  60.5     2.8      M    M
 27000  -43.0 -45.4   220   49   25   8.9   4.9   15.6  60.0     2.7      M    M
 26000  -40.4 -40.7   220   48   25   8.5   4.7   15.3  59.5     2.5      M    M
 25000  -37.9 -36.2   220   43   22   8.5   4.7   14.7  58.5     2.0      M    M
 24000  -35.3 -31.5   220   38   20   8.5   4.7   14.3  57.8     1.7      M    M
 23000  -32.8 -27.0   225   33   17   8.2   4.5   13.9  57.1     1.4      M    M
 22000  -30.3 -22.5   225   31   16   8.2   4.5   13.3  56.0     0.9      M    M
 21000  -27.2 -17.0   225   28   14   8.2   4.5   12.7  54.9     0.4      M    M
 20000  -24.8 -12.6   225   26   13   8.2   4.5   12.2  53.9    -0.1   1184  6.0
 19500  -23.6 -10.5   225   25   13   8.3   4.5   11.9  53.4    -0.4   1132  5.8
 19000  -22.3  -8.1   225   24   12   8.3   4.5   11.6  52.9    -0.6   1081  5.5
 18500  -21.1  -6.0   225   23   12   8.3   4.5   11.4  52.5    -0.8   1030  5.2
 18000  -19.9  -3.8   220   22   11   8.6   4.7   11.2  52.2    -1.0    978  5.0
 17500  -18.6  -1.5   220   21   11   8.8   4.8   11.0  51.9    -1.2    924  4.7
 17000  -17.3   0.9   215   20   10   8.8   4.8   10.9  51.6    -1.3    870  4.4
 16500  -16.0   3.2   210   19   10   8.5   4.7   10.7  51.3    -1.5    817  4.1
 16000  -14.7   5.5   210   17    9   8.6   4.7   10.5  50.9    -1.7    764  3.9
 15500  -13.5   7.7   210   16    8   7.4   4.1   10.2  50.4    -2.0    713  3.6
 15000  -12.5   9.5   210   14    7   7.3   4.0    9.8  49.7    -2.4    666  3.4
 14500  -11.4  11.5   210   12    6   7.1   3.9    9.4  49.0    -2.8    619  3.1
 14000  -10.3  13.5   230   12    6   7.0   3.8    9.0  48.2    -3.2    574  2.9
 13500   -9.3  15.3   250   13    7   6.7   3.7    8.6  47.4    -3.7    528  2.7
 13000   -8.4  16.9   255   13    7   5.6   3.1    8.0  46.4    -4.2    487  2.5
 12500   -7.3  18.9   270   12    6   9.2   5.1    7.7  45.8    -4.6    439  2.2
 12000   -6.2  20.8   280   13    7   7.3   4.0    7.3  45.2    -5.0    390  2.0
 11750   -5.6  21.9   280   14    7   7.0   3.9    7.1  44.9    -5.2    366  1.9
 11500   -5.1  22.8   285   15    7   9.3   5.1    7.0  44.6    -5.3    342  1.7
 11250   -4.3  24.3   280   17    9   8.9   4.9    7.0  44.6    -5.3    312  1.6
 11000   -3.8  25.2   285   18    9   6.7   3.7    6.8  44.2    -5.6    289  1.5
 10750   -3.3  26.1   290   19   10   7.0   3.9    6.6  43.9    -5.8    266  1.4
 10500   -2.8  27.0   290   20   10   7.9   4.3    6.4  43.5    -6.0    244  1.2
 10250   -2.2  28.0   295   20   10   8.2   4.5    6.3  43.3    -6.2    218  1.1
 10000   -1.6  29.1   295   19   10   7.5   4.1    6.1  43.0    -6.4    194  1.0
  9750   -1.1  30.0   300   18    9   7.6   4.2    6.0  42.7    -6.6    170  0.9
  9500   -0.5  31.1   300   18    9   8.2   4.5    5.8  42.5    -6.8    147  0.7
  9250    0.1  32.2   305   17    9   8.4   4.6    5.7  42.3    -6.9    121  0.6
  9000    0.6  33.1   305   17    9   6.9   3.8    5.6  42.0    -7.1     97  0.5
  8750    1.1  34.0   300   17    9   7.0   3.9    5.3  41.6    -7.4     75  0.4
  8500    1.6  34.9   300   17    9   5.1   2.8    5.1  41.2    -7.6     53  0.3
  8250    1.8  35.2   300   17    9   1.2   0.7    4.6  40.3    -8.2     40  0.2
  8000    1.8  35.2   295   17    9   0.4   0.2    3.9  39.0    -8.9     32  0.2
  7750   -1.5  29.3   280    7    3 -81.8 -44.9   -0.8  30.5   -13.7    116  0.6
  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 * * * * * *

           03/24/2024 at 0900 MDT          |       03/24/2024 at 1200 MDT
                                           |
CAPE...   +43.8    LI...       +0.2        | CAPE...  +558.5    LI...       -2.1
CINH...   -67.2    K Index... +13.2        | CINH...     0.0    K Index... +19.3
                                           |
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 -54.7 -66.5  245  46 24   1.5   0.8 | -53.7 -64.7  240  46 24   1.9   1.1
 45000 -52.4 -62.3  240  58 30   1.5   0.8 | -50.8 -59.4  240  52 27   1.9   1.1
 40000 -52.6 -62.7  235  56 29  -0.5  -0.3 | -51.1 -60.0  235  48 25  -0.7  -0.4
 38000 -52.9 -63.2  235  54 28  -1.0  -0.5 | -51.5 -60.7  230  46 24  -1.2  -0.7
 36000 -53.6 -64.5  235  47 24  -1.1  -0.6 | -52.5 -62.5  225  39 20  -1.7  -0.9
 34000 -54.3 -65.7  230  40 21  -1.1  -0.6 | -53.5 -64.3  220  32 16  -1.7  -0.9
 32000 -53.4 -64.1  220  35 18   2.9   1.6 | -52.7 -62.9  215  27 14   3.0   1.6
 30000 -51.6 -60.9  210  33 17   3.1   1.7 | -50.9 -59.6  205  25 13   3.0   1.7
 29000 -49.9 -57.8  205  32 17   8.8   4.9 | -49.7 -57.5  200  23 12   6.9   3.8
 28000 -47.3 -53.1  210  32 16   8.9   4.9 | -47.7 -53.9  210  20 10   6.6   3.6
 27000 -44.6 -48.3  215  32 16   8.9   4.9 | -45.2 -49.4  225  16  8   6.6   3.6
 26000 -41.3 -42.3  220  30 16   8.4   4.6 | -43.0 -45.4  235  15  8   9.4   5.2
 25000 -38.8 -37.8  220  27 14   8.4   4.6 | -40.2 -40.4  235  16  8   9.4   5.2
 24000 -36.2 -33.2  220  23 12   8.4   4.6 | -37.4 -35.3  235  18  9   9.4   5.2
 23000 -33.7 -28.7  220  20 10   8.6   4.7 | -34.6 -30.3  230  19 10   8.9   4.9
 22000 -31.1 -24.0  220  19 10   8.6   4.7 | -31.9 -25.4  230  20 10   8.9   4.9
 21000 -28.6 -19.5  220  19 10   8.6   4.7 | -29.3 -20.7  230  20 10   8.8   4.9
 20000 -26.1 -15.0  220  19 10   8.4   4.6 | -26.7 -16.1  225  20 10   8.2   4.5
 19500 -24.8 -12.6  220  19 10   8.4   4.6 | -25.5 -13.9  225  20 10   8.2   4.5
 19000 -23.5 -10.3  220  19 10   8.4   4.6 | -24.3 -11.7  225  19 10   8.2   4.5
 18500 -22.3  -8.1  220  19 10   8.4   4.6 | -23.1  -9.6  225  19 10   8.2   4.5
 18000 -21.0  -5.8  220  19 10   8.5   4.7 | -21.8  -7.2  225  19 10   8.2   4.5
 17500 -19.7  -3.5  220  19 10   8.9   4.9 | -20.6  -5.1  225  18 10   8.3   4.5
 17000 -18.4  -1.1  220  20 10   8.9   4.9 | -19.4  -2.9  225  18  9   8.3   4.6
 16500 -17.2   1.0  225  20 10   8.0   4.4 | -18.2  -0.8  230  18  9   8.0   4.4
 16000 -16.0   3.2  225  19 10   8.1   4.4 | -17.0   1.4  230  16  8   8.0   4.4
 15500 -14.8   5.4  225  19 10   8.0   4.4 | -15.8   3.6  230  14  7   8.0   4.4
 15000 -13.6   7.5  225  17  9   7.9   4.3 | -14.6   5.7  225  12  6   8.1   4.4
 14500 -12.4   9.7  230  15  8   7.7   4.2 | -13.5   7.7  220   9  5   8.1   4.4
 14000 -11.4  11.5  225  12  6   7.0   3.9 | -12.3   9.9  200   6  3   7.6   4.2
 13500 -10.4  13.3  225   8  4   6.9   3.8 | -11.2  11.8  160   6  3   7.7   4.2
 13000  -9.5  14.9  215   5  3   5.0   2.7 | -10.1  13.8  130   8  4   6.8   3.8
 12500  -8.4  16.9  175   2  1   9.3   5.1 |  -9.0  15.8  115  11  5   8.6   4.7
 12000  -7.2  19.0  080   2  1   7.9   4.4 |  -7.8  18.0  105  11  6   8.4   4.6
 11750  -6.6  20.1  050   2  1   7.9   4.3 |  -7.2  19.0  100  11  6   8.4   4.6
 11500  -6.0  21.2  035   4  2   8.7   4.8 |  -6.6  20.1  095  10  5   8.6   4.7
 11250  -5.4  22.3  020   5  2   9.3   5.1 |  -5.9  21.4  090  10  5   9.5   5.2
 11000  -4.7  23.5  015   4  2   9.0   4.9 |  -5.2  22.6  090   9  5  10.2   5.6
 10750  -4.0  24.8  015   4  2   9.2   5.1 |  -4.4  24.1  090   9  5  10.5   5.8
 10500  -3.3  26.1  010   4  2   8.7   4.7 |  -3.7  25.3  085   9  5   9.4   5.2
 10250  -2.7  27.1  005   5  2   8.2   4.5 |  -3.0  26.6  085   9  5   8.3   4.5
 10000  -2.1  28.2  005   4  2   8.5   4.6 |  -1.7  28.9  080   9  5  10.1   5.5
  9750  -1.5  29.3  005   4  2   8.3   4.6 |  -0.9  30.4  080   9  4   9.4   5.2
  9500  -0.9  30.4  005   3  2   8.7   4.8 |  -0.2  31.6  080   9  4  11.4   6.3
  9250  -0.2  31.6  005   3  2   8.9   4.9 |   0.7  33.3  080   8  4  10.9   6.0
  9000   0.4  32.7  350   3  1   7.9   4.3 |   1.4  34.5  080   8  4   8.7   4.8
  8750   1.5  34.7  315   3  1   7.1   3.9 |   2.1  35.8  080   8  4   9.1   5.0
  8500   2.0  35.6  300   3  2   5.8   3.2 |   2.8  37.0  080   8  4  12.0   6.6
  8250   2.4  36.3  285   4  2   5.1   2.8 |   3.9  39.0  075   8  4  16.5   9.1
  8000   2.7  36.9  275   4  2   5.1   2.8 |   5.1  41.2  075   8  4  16.9   9.3
  7750   3.0  37.4  270   4  2   5.1   2.8 |   6.4  43.5  075   7  4  18.4  10.1
  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

           03/24/2024 at 1500 MDT          |       03/24/2024 at 1800 MDT
                                           |
CAPE...  +457.6    LI...       -1.7        | CAPE...    +4.1    LI...       -0.0
CINH...   -15.8    K Index... +22.9        | CINH...    -2.4    K Index... +22.5
                                           |
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 -53.5 -64.3  230  45 23   2.0   1.1 | -52.9 -63.2  235  46 24   2.0   1.1
 45000 -50.4 -58.7  250  44 23   2.0   1.1 | -50.0 -58.0  240  37 19   2.0   1.1
 40000 -50.7 -59.3  240  43 22  -0.7  -0.4 | -51.0 -59.8  230  40 20  -1.2  -0.7
 38000 -51.2 -60.2  230  43 22  -1.9  -1.0 | -51.7 -61.1  230  42 22  -3.3  -1.8
 36000 -53.0 -63.4  230  36 18  -3.0  -1.7 | -54.9 -66.8  230  27 14  -5.3  -2.9
 34000 -54.8 -66.6  230  28 15  -3.1  -1.7 | -58.0 -72.4  240  13  7  -5.3  -2.9
 32000 -54.0 -65.2  240  23 12   3.9   2.1 | -56.3 -69.3  260   5  3   7.5   4.1
 30000 -51.7 -61.1  265  20 10   3.9   2.2 | -51.8 -61.2  335   3  1   7.5   4.1
 29000 -50.0 -58.0  270  19 10   8.9   4.9 | -49.3 -56.7  005   3  2   9.7   5.3
 28000 -47.4 -53.3  275  17  9   8.6   4.7 | -46.4 -51.5  020   3  2   9.7   5.3
 27000 -44.8 -48.6  275  15  8   8.6   4.7 | -43.5 -46.3  035   4  2   9.7   5.3
 26000 -42.2 -44.0  280  13  7   8.8   4.8 | -40.6 -41.1  045   4  2   9.4   5.2
 25000 -38.9 -38.0  265  12  6   9.1   5.0 | -37.1 -34.8  050   5  3   9.2   5.1
 24000 -36.1 -33.0  250  12  6   9.1   5.0 | -34.4 -29.9  050   6  3   9.2   5.1
 23000 -33.5 -28.3  235  13  6   8.7   4.8 | -31.7 -25.1  055   7  3   8.7   4.8
 22000 -30.9 -23.6  225  12  6   8.7   4.8 | -29.1 -20.4  055   7  4   8.7   4.8
 21000 -28.3 -18.9  215  13  7   8.7   4.8 | -26.5 -15.7  060   8  4   8.7   4.8
 20000 -25.7 -14.3  200  14  7   8.2   4.5 | -24.0 -11.2  060   9  5   7.8   4.3
 19500 -24.5 -12.1  195  13  7   8.2   4.5 | -22.8  -9.0  060  10  5   7.8   4.3
 19000 -23.3  -9.9  185  14  7   8.2   4.5 | -21.7  -7.1  060  10  5   7.8   4.3
 18500 -22.1  -7.8  180  14  7   8.2   4.5 | -20.5  -4.9  060  11  5   7.9   4.3
 18000 -20.9  -5.6  170  15  8   8.3   4.5 | -19.3  -2.7  060  11  6   7.9   4.3
 17500 -19.7  -3.5  165  15  8   7.2   4.0 | -18.2  -0.8  060  12  6   7.6   4.1
 17000 -18.6  -1.5  155  15  8   7.3   4.0 | -17.1   1.2  060  13  6   7.6   4.2
 16500 -17.6   0.3  150  15  8   7.3   4.0 | -16.0   3.2  060  13  7   7.4   4.1
 16000 -16.5   2.3  140  16  8   7.4   4.0 | -14.9   5.2  060  14  7   7.3   4.0
 15500 -15.4   4.3  135  16  8   7.6   4.2 | -13.8   7.2  055  15  8   7.3   4.0
 15000 -14.2   6.4  125  16  8   8.4   4.6 | -12.8   9.0  055  16  8   7.2   3.9
 14500 -13.0   8.6  120  16  8   8.4   4.6 | -11.7  10.9  055  17  9   7.2   4.0
 14000 -11.8  10.8  115  16  8   8.4   4.6 | -10.7  12.7  055  18  9   6.7   3.7
 13500 -10.5  13.1  105  16  8   8.5   4.7 |  -9.7  14.5  055  19 10   6.7   3.7
 13000  -9.4  15.1  100  16  8   7.4   4.0 |  -8.7  16.3  055  20 10   7.6   4.2
 12500  -8.3  17.1  095  15  8   7.7   4.2 |  -7.7  18.1  055  21 11   6.4   3.5
 12000  -7.1  19.2  095  15  8   9.2   5.1 |  -6.7  19.9  050  21 11   6.8   3.7
 11750  -6.4  20.5  090  14  7   9.7   5.3 |  -6.2  20.8  050  22 11   7.0   3.8
 11500  -5.7  21.7  090  14  7   8.1   4.4 |  -5.8  21.6  050  22 11   6.4   3.5
 11250  -5.2  22.6  090  14  7   7.6   4.1 |  -5.3  22.5  050  22 11   5.9   3.2
 11000  -4.5  23.9  085  14  7   9.2   5.1 |  -4.9  23.2  050  22 11   6.5   3.6
 10750  -3.8  25.2  085  13  7  10.0   5.5 |  -3.9  25.0  050  22 11   6.6   3.6
 10500  -3.1  26.4  080  13  7   8.7   4.8 |  -3.5  25.7  050  22 11   4.8   2.6
 10250  -2.6  27.3  080  13  7   6.2   3.4 |  -3.2  26.2  050  22 11   4.6   2.5
 10000  -2.1  28.2  075  13  6   8.3   4.5 |  -2.8  27.0  045  21 11   5.6   3.1
  9750  -1.3  29.7  070  12  6  10.2   5.6 |  -2.4  27.7  045  21 11   5.5   3.0
  9500  -0.6  30.9  070  12  6  10.5   5.8 |  -2.0  28.4  045  20 11   5.0   2.8
  9250   0.5  32.9  060  12  6   6.4   3.5 |  -1.7  28.9  045  20 10   3.7   2.0
  9000   1.1  34.0  060  11  6   9.4   5.1 |  -1.5  29.3  040  19 10   3.2   1.8
  8750   1.8  35.2  055  11  6   8.0   4.4 |  -1.2  29.8  040  18  9   3.2   1.8
  8500   2.4  36.3  050  11  6  10.5   5.7 |  -1.0  30.2  035  17  9   3.7   2.0
  8250   3.3  37.9  045  10  5  12.7   7.0 |  -0.7  30.7  030  15  7   5.3   2.9
  8000   4.1  39.4  045   9  5  10.0   5.5 |  -0.2  31.6  020  10  5   6.3   3.5
  7750   5.0  41.0  040   7  4  16.8   9.2 |   0.2  32.4  010   7  3   4.9   2.7
  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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