Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 231259
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0659 MDT Saturday, March 23, 2024

This forecast is for the Air Force Academy for Saturday, March 23, 2024:

If the trigger temperature of 49.4 F/9.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1284 ft/min (6.5 m/s)
   Maximum height of thermals.................. 22863 ft MSL (15261 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1400 MDT
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................. 17972 ft MSL (10371 ft AGL)
Thermal soaring outlook for Sunday 03/24....... Good

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

Remarks...

Sunrise/Sunset.................... 06:56:37 / 19:14:33 MDT
Total possible sunshine........... 12 hr 17 min 56 sec (737 min 56 sec)
Altitude of sun at 13:05:35 MDT... 52.44 degrees

Upper air data from numerical model forecast valid on 03/23/2024 at 0600 MDT

Freezing level.................. 7644 ft MSL (42 ft AGL)
Additional freezing level....... 10812 ft MSL (3210 ft AGL)
Convective condensation level... 15808 ft MSL (8206 ft AGL)
Lifted condensation level....... 18007 ft MSL (10406 ft AGL)
Lifted index.................... -3.9
K index......................... +17.0

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  -57.8 -72.0   275   73   38   1.2   0.7      M     M       M      M    M
 45000  -56.0 -68.8   280   84   43   1.4   0.8      M     M       M      M    M
 40000  -58.0 -72.4   280   81   42  -1.5  -0.8      M     M       M      M    M
 38000  -58.4 -73.1   275   76   39   1.1   0.6      M     M       M      M    M
 36000  -57.6 -71.7   275   62   32   1.2   0.6      M     M       M      M    M
 34000  -56.6 -69.9   270   51   26   6.6   3.6      M     M       M      M    M
 32000  -52.6 -62.7   270   48   24   6.7   3.6      M     M       M      M    M
 30000  -48.4 -55.1   270   44   23   9.3   5.1   19.3  66.8     1.6      M    M
 29000  -45.7 -50.3   265   42   22   9.0   5.0   18.9  66.1     1.3      M    M
 28000  -43.0 -45.4   260   40   21   9.0   5.0   18.7  65.6     1.1      M    M
 27000  -40.3 -40.5   255   39   20   9.1   5.0   18.5  65.4     1.0      M    M
 26000  -37.5 -35.5   260   38   20   9.3   5.1   18.3  64.9     0.8      M    M
 25000  -34.7 -30.5   260   38   20   9.3   5.1   18.1  64.5     0.7      M    M
 24000  -31.9 -25.4   265   38   20   9.4   5.2   18.0  64.4     0.6      M    M
 23000  -29.4 -20.9   265   38   20   8.1   4.4   17.4  63.4     0.1      M    M
 22000  -27.0 -16.6   270   38   20   8.1   4.5   16.8  62.3    -0.4   1406  7.1
 21000  -24.0 -11.2   275   38   20   7.7   4.2   16.2  61.1    -1.0   1279  6.5
 20000  -21.7  -7.1   275   38   20   7.7   4.2   15.4  59.7    -1.7   1181  6.0
 19500  -20.6  -5.1   275   38   19   7.7   4.2   15.1  59.1    -2.0   1132  5.8
 19000  -19.5  -3.1   275   38   19   7.7   4.2   14.7  58.5    -2.3   1083  5.5
 18500  -18.3  -0.9   275   37   19   7.6   4.1   14.4  58.0    -2.6   1035  5.3
 18000  -17.2   1.0   270   36   19   7.5   4.1   14.0  57.3    -3.0    987  5.0
 17500  -16.1   3.0   270   35   18   7.4   4.0   13.7  56.6    -3.4    939  4.8
 17000  -15.1   4.8   265   35   18   6.7   3.7   13.2  55.7    -3.9    893  4.5
 16500  -14.1   6.6   265   35   18   6.7   3.7   12.7  54.8    -4.3    849  4.3
 16000  -13.1   8.4   260   35   18   7.3   4.0   12.2  54.0    -4.8    803  4.1
 15500  -12.0  10.4   255   35   18   7.3   4.0   11.8  53.3    -5.2    756  3.8
 15000  -10.9  12.4   255   35   18   7.8   4.3   11.5  52.6    -5.6    708  3.6
 14500   -9.7  14.5   255   33   17   8.0   4.4   11.2  52.1    -5.9    658  3.3
 14000   -8.5  16.7   250   31   16   8.1   4.5   10.9  51.6    -6.2    608  3.1
 13500   -7.3  18.9   250   28   15   8.4   4.6   10.6  51.2    -6.5    557  2.8
 13000   -6.1  21.0   250   25   13  10.5   5.7   10.4  50.7    -6.8    506  2.6
 12500   -4.6  23.7   250   24   13   7.9   4.3   10.5  51.0    -6.8    444  2.3
 12000   -3.4  25.9   245   23   12   8.1   4.5   10.2  50.4    -7.1    395  2.0
 11750   -2.8  27.0   245   23   12   8.8   4.8   10.1  50.2    -7.2    368  1.9
 11500   -2.1  28.2   245   22   11   9.4   5.2   10.1  50.2    -7.3    341  1.7
 11250   -1.4  29.5   250   22   11   9.9   5.5   10.1  50.1    -7.3    312  1.6
 11000   -0.6  30.9   250   21   11   9.4   5.2   10.1  50.2    -7.3    282  1.4
 10750    0.0  32.0   250   21   11   8.5   4.6   10.0  50.0    -7.4    255  1.3
 10500    0.6  33.1   250   21   11   7.9   4.3    9.9  49.8    -7.5    229  1.2
 10250    1.3  34.3   250   21   11  10.8   5.9    9.8  49.7    -7.6    202  1.0
 10000    2.2  36.0   250   21   11  11.2   6.1   10.0  50.0    -7.5    168  0.9
  9750    2.9  37.2   250   20   11   8.0   4.4   10.0  49.9    -7.5    140  0.7
  9500    3.5  38.3   250   20   10   7.0   3.9    9.8  49.6    -7.7    115  0.6
  9250    4.0  39.2   250   20   10   9.5   5.2    9.6  49.3    -7.9     91  0.5
  9000    4.8  40.6   255   19   10   7.5   4.1    9.6  49.3    -7.9     61  0.3
  8750    5.0  41.0   250   18    9   1.6   0.9    9.2  48.5    -8.4     45  0.2
  8500    5.2  41.4   250   17    9   4.7   2.6    8.6  47.5    -9.0     34  0.2
  8250    5.3  41.5   250   16    8  -6.2  -3.4    8.1  46.5    -9.6     22  0.1
  8000    4.0  39.2   245   15    8 -26.5 -14.5    6.0  42.8   -11.7     55  0.3
  7750    1.8  35.2   235   10    5 -27.4 -15.0    3.1  37.6   -14.7    113  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 * * * * * *

           03/23/2024 at 0900 MDT          |       03/23/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +0.6        | CAPE...  +385.2    LI...       -0.6
CINH...     0.0    K Index... +16.6        | CINH...    -5.7    K Index... +12.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.4 -73.1  275  74 38   0.6   0.3 | -58.5 -73.3  270  74 38   0.9   0.5
 45000 -57.5 -71.5  280  87 45   0.6   0.3 | -57.1 -70.8  270  96 50   1.2   0.6
 40000 -57.0 -70.6  275  90 47   0.3   0.2 | -58.2 -72.8  270  98 50  -0.8  -0.5
 38000 -56.6 -69.9  275  86 44   1.2   0.7 | -57.9 -72.2  270  94 48   3.2   1.7
 36000 -55.8 -68.4  270  69 36   1.3   0.7 | -55.8 -68.4  270  80 41   3.2   1.7
 34000 -54.7 -66.5  270  55 29   5.9   3.2 | -53.7 -64.7  265  69 35   5.9   3.2
 32000 -51.3 -60.3  265  50 26   5.7   3.1 | -50.3 -58.5  265  62 32   5.6   3.1
 30000 -47.7 -53.9  265  44 23   8.7   4.8 | -46.7 -52.1  260  55 28   8.0   4.4
 29000 -45.2 -49.4  265  41 21   8.4   4.6 | -44.4 -47.9  260  54 28   7.8   4.3
 28000 -42.6 -44.7  260  38 20   8.4   4.6 | -42.1 -43.8  260  52 27   7.8   4.3
 27000 -40.1 -40.2  260  35 18   8.5   4.6 | -39.8 -39.6  260  51 26   7.8   4.3
 26000 -37.5 -35.5  260  34 17   8.9   4.9 | -37.2 -35.0  265  47 24   8.6   4.7
 25000 -34.8 -30.6  255  33 17   8.9   4.9 | -34.7 -30.5  270  43 22   8.6   4.7
 24000 -32.2 -26.0  255  32 16   8.9   4.9 | -32.1 -25.8  275  40 20   8.6   4.7
 23000 -29.6 -21.3  255  31 16   8.6   4.7 | -29.6 -21.3  275  37 19   8.4   4.6
 22000 -27.0 -16.6  260  32 16   8.6   4.7 | -27.0 -16.6  270  36 18   8.4   4.6
 21000 -23.9 -11.0  265  32 16   8.0   4.4 | -23.8 -10.8  265  33 17   8.9   4.9
 20000 -21.5  -6.7  270  32 16   8.0   4.4 | -21.2  -6.2  260  27 14   8.9   4.9
 19500 -20.3  -4.5  270  32 16   8.0   4.4 | -19.8  -3.6  250  24 12   8.9   4.9
 19000 -19.1  -2.4  275  32 16   8.0   4.4 | -18.5  -1.3  245  22 11   9.0   4.9
 18500 -17.9  -0.2  275  32 17   7.4   4.0 | -17.2   1.0  235  20 11   8.3   4.6
 18000 -16.9   1.6  275  33 17   7.2   3.9 | -16.0   3.2  245  21 11   8.1   4.4
 17500 -15.8   3.6  275  34 17   7.2   3.9 | -14.8   5.4  250  23 12   7.9   4.4
 17000 -14.8   5.4  275  34 18   7.3   4.0 | -13.7   7.3  250  23 12   7.0   3.9
 16500 -13.7   7.3  275  35 18   7.3   4.0 | -12.6   9.3  250  23 12   7.1   3.9
 16000 -12.6   9.3  275  36 19   7.6   4.2 | -11.6  11.1  250  24 12   6.8   3.8
 15500 -11.5  11.3  270  37 19   7.6   4.2 | -10.6  12.9  255  26 13   6.8   3.7
 15000 -10.4  13.3  270  38 20   8.0   4.4 |  -9.6  14.7  255  28 14   6.4   3.5
 14500  -9.2  15.4  270  39 20   8.2   4.5 |  -8.7  16.3  255  30 16   6.1   3.3
 14000  -7.9  17.8  270  40 21   8.5   4.7 |  -7.8  18.0  255  33 17   6.2   3.4
 13500  -6.6  20.1  270  41 21   9.0   4.9 |  -7.0  19.4  255  33 17   6.7   3.7
 13000  -5.3  22.5  270  41 21   9.7   5.3 |  -6.1  21.0  255  33 17   9.6   5.3
 12500  -4.0  24.8  265  40 20   7.3   4.0 |  -4.7  23.5  255  31 16   7.7   4.2
 12000  -3.0  26.6  265  38 20   7.3   4.0 |  -3.5  25.7  255  26 13   8.0   4.4
 11750  -2.4  27.7  265  37 19   7.6   4.2 |  -2.9  26.8  255  24 12   9.3   5.1
 11500  -1.9  28.6  265  35 18   6.7   3.7 |  -2.2  28.0  255  23 12   9.7   5.3
 11250  -1.4  29.5  260  33 17   5.6   3.1 |  -1.5  29.3  255  22 11   9.2   5.0
 11000  -1.0  30.2  260  31 16   6.0   3.3 |  -0.8  30.6  255  21 11   9.2   5.0
 10750  -0.6  30.9  260  29 15   6.5   3.6 |  -0.2  31.6  255  20 10   8.2   4.5
 10500  -0.1  31.8  255  27 14   6.7   3.7 |   0.4  32.7  255  19 10   7.8   4.3
 10250   0.4  32.7  255  25 13   7.5   4.1 |   1.0  33.8  250  18  9   9.7   5.3
 10000   1.0  33.8  255  26 13   7.8   4.3 |   1.8  35.2  250  17  9  10.3   5.7
  9750   1.5  34.7  250  26 13   7.0   3.8 |   2.5  36.5  250  16  8   8.5   4.7
  9500   2.0  35.6  250  25 13   6.7   3.7 |   3.1  37.6  245  15  8   7.3   4.0
  9250   2.5  36.5  250  25 13   7.2   4.0 |   3.6  38.5  240  14  7   9.4   5.1
  9000   3.0  37.4  250  24 12   5.6   3.1 |   4.4  39.9  240  13  6  11.0   6.1
  8750   3.4  38.1  250  23 12   4.0   2.2 |   5.2  41.4  235  12  6   9.4   5.2
  8500   3.6  38.5  250  21 11   2.6   1.4 |   5.9  42.6  230  11  6   9.0   4.9
  8250   3.9  39.0  250  19 10   7.9   4.3 |   6.5  43.7  225  10  5   8.6   4.7
  8000   4.6  40.3  245  16  8   7.3   4.0 |   7.2  45.0  220   9  5  12.5   6.8
  7750   4.5  40.1  240  11  6  -9.4  -5.1 |   8.4  47.1  215   9  4  20.5  11.3
  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

           03/23/2024 at 1500 MDT          |       03/23/2024 at 1800 MDT
                                           |
CAPE...  +646.7    LI...       -2.2        | CAPE...  +319.2    LI...       -1.0
CINH...   -12.3    K Index... +24.5        | CINH...   -27.5    K Index... +20.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.2 -74.6  265  71 37   0.7   0.4 | -59.1 -74.4  265  75 39   0.2   0.1
 45000 -58.0 -72.4  265  95 49   0.8   0.4 | -58.8 -73.8  260  96 49   0.2   0.1
 40000 -57.7 -71.9  265 113 58   0.2   0.1 | -57.9 -72.2  260 120 62   0.6   0.3
 38000 -56.9 -70.4  265 114 58   3.6   2.0 | -56.9 -70.4  255 122 63   3.4   1.9
 36000 -54.7 -66.5  265 104 54   3.6   2.0 | -54.9 -66.8  255 109 56   3.4   1.9
 34000 -52.2 -62.0  265  93 48   5.5   3.0 | -52.8 -63.0  255  96 50   4.2   2.3
 32000 -48.9 -56.0  260  78 40   5.4   2.9 | -49.2 -56.6  255  76 39   5.4   3.0
 30000 -45.6 -50.1  260  64 33   6.5   3.6 | -45.9 -50.6  250  60 31   8.1   4.4
 29000 -43.7 -46.7  255  61 32   6.4   3.5 | -43.5 -46.3  245  59 30   7.8   4.3
 28000 -41.8 -43.2  255  59 31   6.4   3.5 | -41.2 -42.2  240  59 30   7.8   4.3
 27000 -39.9 -39.8  250  57 30   6.2   3.4 | -38.9 -38.0  240  59 30   7.8   4.3
 26000 -37.4 -35.3  250  53 27   9.2   5.0 | -36.4 -33.5  240  53 28   8.3   4.5
 25000 -34.7 -30.5  255  47 24   9.2   5.0 | -34.0 -29.2  245  46 24   8.3   4.5
 24000 -31.9 -25.4  255  42 22   9.2   5.1 | -31.5 -24.7  250  39 20   8.3   4.5
 23000 -29.3 -20.7  255  40 21   8.6   4.7 | -29.0 -20.2  245  35 18   8.5   4.7
 22000 -26.7 -16.1  255  39 20   8.6   4.7 | -26.5 -15.7  235  32 16   8.5   4.7
 21000 -24.2 -11.6  250  39 20   8.5   4.7 | -23.9 -11.0  225  29 15   8.6   4.7
 20000 -21.2  -6.2  245  34 17   7.8   4.3 | -21.8  -7.2  230  31 16   7.0   3.9
 19500 -20.1  -4.2  240  32 16   7.8   4.3 | -20.7  -5.3  230  31 16   7.0   3.9
 19000 -18.9  -2.0  235  30 16   7.8   4.3 | -19.2  -2.6  235  33 17   7.1   3.9
 18500 -17.8  -0.0  230  29 15   7.4   4.1 | -18.1  -0.6  240  34 18   7.1   3.9
 18000 -16.7   1.9  230  27 14   7.1   3.9 | -17.0   1.4  245  33 17   7.3   4.0
 17500 -15.7   3.7  230  26 13   7.0   3.9 | -16.0   3.2  250  32 16   7.2   3.9
 17000 -14.6   5.7  235  27 14   7.3   4.0 | -14.8   5.4  255  29 15   8.4   4.6
 16500 -13.6   7.5  245  29 15   7.2   4.0 | -13.6   7.5  250  25 13   8.4   4.6
 16000 -12.5   9.5  250  30 16   8.5   4.6 | -12.4   9.7  250  21 11   8.3   4.5
 15500 -11.2  11.8  250  28 15   8.8   4.8 | -11.2  11.8  250  20 10   8.2   4.5
 15000 -10.0  14.0  255  26 14   8.7   4.8 | -10.0  14.0  250  19 10   8.3   4.6
 14500  -8.7  16.3  250  24 12   8.6   4.7 |  -8.8  16.2  245  20 10   8.6   4.7
 14000  -7.5  18.5  250  21 11   8.6   4.7 |  -7.5  18.5  245  21 11   8.6   4.7
 13500  -6.2  20.8  245  20 10   8.8   4.8 |  -6.0  21.2  240  22 11  10.9   6.0
 13000  -5.0  23.0  245  20 10  11.8   6.5 |  -4.4  24.1  240  22 11   8.1   4.5
 12500  -3.3  26.1  240  19 10   7.5   4.1 |  -3.3  26.1  240  22 11   9.4   5.1
 12000  -2.1  28.2  240  18  9   8.2   4.5 |  -1.9  28.6  235  22 11   9.1   5.0
 11750  -1.4  29.5  240  18  9   9.3   5.1 |  -1.2  29.8  235  22 11  10.4   5.7
 11500  -0.7  30.7  235  18  9   9.6   5.2 |  -0.4  31.3  235  22 11  10.5   5.8
 11250  -0.0  32.0  235  17  9   8.8   4.8 |   0.3  32.5  230  22 11   9.1   5.0
 11000   0.6  33.1  230  17  9   9.4   5.1 |   1.0  33.8  230  22 11   9.7   5.3
 10750   1.3  34.3  230  16  8   7.7   4.2 |   1.7  35.1  230  22 11   8.9   4.9
 10500   1.8  35.2  225  16  8   6.6   3.6 |   2.4  36.3  230  22 11   8.4   4.6
 10250   2.4  36.3  220  16  8   9.4   5.2 |   3.0  37.4  225  22 11   9.5   5.2
 10000   3.1  37.6  215  15  8  10.9   6.0 |   3.8  38.8  225  22 11  10.4   5.7
  9750   3.9  39.0  210  15  8   9.0   5.0 |   4.5  40.1  225  22 11   9.2   5.1
  9500   4.5  40.1  210  15  8   7.5   4.1 |   5.1  41.2  220  21 11   7.8   4.3
  9250   5.1  41.2  205  15  8   8.7   4.8 |   5.7  42.3  220  21 11   8.6   4.7
  9000   5.8  42.4  200  15  8   9.8   5.4 |   6.4  43.5  215  21 11  10.6   5.8
  8750   6.5  43.7  200  15  8   9.0   4.9 |   7.2  45.0  215  20 10   8.7   4.8
  8500   7.1  44.8  195  14  7   8.1   4.4 |   7.7  45.9  210  20 10   6.6   3.6
  8250   7.7  45.9  195  14  7   8.9   4.9 |   8.2  46.8  205  19 10   7.5   4.1
  8000   8.3  46.9  190  14  7   8.8   4.8 |   8.7  47.7  205  18  9   6.7   3.7
  7750   8.8  47.8  185  12  6   6.0   3.3 |   9.0  48.2  200  15  8   1.5   0.8
  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
________________________________________________________________________________

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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