Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231306
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
706 AM MDT Saturday, March 23, 2024

This forecast is for Saturday, March 23, 2024:

If the trigger temperature of 61.1 F/16.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 841 ft/min (4.3 m/s)
   Maximum height of thermals.................. 16132 ft MSL (11293 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9305 ft MSL (4466 ft AGL)
Thermal soaring outlook for Sunday 03/24....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:11:26 / 19:29:26 MDT
Total possible sunshine........... 12 hr 18 min 0 sec (738 min 0 sec)
Altitude of sun at 13:20:26 MDT... 52.04 degrees

Upper air data from rawinsonde observation taken on 03/23/2024 at 0600 MDT

Freezing level.................. 10427 ft MSL (5588 ft AGL)
Convective condensation level... 14945 ft MSL (10106 ft AGL)
Lifted condensation level....... 15334 ft MSL (10495 ft AGL)
Lifted index.................... -0.7
K index......................... +18.3

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  -57.0 -70.6   265   71   37   1.6   0.9  107.5 225.5    50.0      M    M
 45000  -56.2 -69.2   280   89   46  -2.3  -1.2   83.9 183.0    39.2      M    M
 40000  -58.0 -72.4   275   93   48  -6.1  -3.3   57.7 135.9    24.9      M    M
 38000  -56.7 -70.1   270   78   40   4.9   2.7   50.8 123.5    21.0      M    M
 36000  -57.9 -72.2   270   67   35   4.0   2.2   40.4 104.7    14.4      M    M
 34000  -54.7 -66.5   265   56   29   7.0   3.8   35.5  95.9    11.4      M    M
 32000  -50.6 -59.1   270   48   25   6.5   3.6   33.1  91.6     9.9      M    M
 30000  -47.5 -53.5   260   52   27   7.7   4.2   29.3  84.8     7.4      M    M
 29000  -45.3 -49.5   265   50   26   7.3   4.0   28.4  83.1     6.8      M    M
 28000  -43.1 -45.6   265   52   27   7.3   4.0   27.5  81.5     6.1      M    M
 27000  -40.9 -41.6   265   53   27   7.3   4.0   26.5  79.7     5.5      M    M
 26000  -38.7 -37.7   260   47   24   7.4   4.0   25.5  77.9     4.7      M    M
 25000  -36.3 -33.3   255   42   22   9.8   5.4   24.9  76.9     4.3      M    M
 24000  -33.4 -28.1   250   39   20   9.0   5.0   24.9  76.7     4.3      M    M
 23000  -30.8 -23.4   250   38   20   8.7   4.8   24.5  76.1     4.1      M    M
 22000  -28.2 -18.8   245   34   18   8.0   4.4   24.1  75.3     3.7      M    M
 21000  -25.8 -14.4   245   35   18   8.0   4.4   23.4  74.2     3.2      M    M
 20000  -23.4 -10.1   240   36   18   8.9   4.9   22.9  73.2     2.8      M    M
 19500  -22.0  -7.6   245   37   19   8.5   4.7   22.7  72.9     2.7      M    M
 19000  -20.6  -5.1   245   33   17   4.2   2.3   21.9  71.4     1.9      M    M
 18500  -19.8  -3.6   245   33   17   7.3   4.0   21.1  70.0     1.2      M    M
 18000  -18.7  -1.7   250   32   16   7.0   3.8   20.7  69.3     0.9      M    M
 17500  -17.6   0.3   245   31   16   6.9   3.8   20.2  68.4     0.5      M    M
 17000  -16.4   2.5   240   29   15   9.7   5.3   19.9  67.9     0.3      M    M
 16500  -15.1   4.8   235   32   17   7.9   4.4   19.8  67.6     0.1      M    M
 16000  -13.9   7.0   235   35   18   8.0   4.4   19.5  67.2    -0.1   1019  5.2
 15500  -12.7   9.1   235   38   19   7.9   4.3   19.2  66.6    -0.4    969  4.9
 15000  -11.6  11.1   235   38   20   7.9   4.3   18.9  66.1    -0.7    920  4.7
 14500  -10.4  13.3   230   33   17   8.1   4.4   18.6  65.5    -1.0    871  4.4
 14000   -9.2  15.4   230   27   14   8.3   4.6   18.4  65.1    -1.3    820  4.2
 13500   -8.0  17.6   225   26   13   8.3   4.6   18.1  64.6    -1.6    769  3.9
 13000   -6.7  19.9   220   24   12   8.8   4.8   18.0  64.3    -1.7    716  3.6
 12500   -5.4  22.3   220   21   11   8.8   4.8   17.8  64.1    -1.9    662  3.4
 12000   -4.1  24.6   230   18    9   8.8   4.8   17.7  63.8    -2.0    608  3.1
 11500   -2.8  27.0   235   19   10   8.8   4.8   17.5  63.5    -2.2    554  2.8
 11000   -1.5  29.3   240   20   10   8.8   4.8   17.4  63.3    -2.4    500  2.5
 10500   -0.2  31.6   245   18   10   8.8   4.8   17.2  63.0    -2.6    446  2.3
 10250    0.4  32.7   245   18    9   8.8   4.8   17.1  62.8    -2.7    419  2.1
 10000    1.1  34.0   245   18    9   8.7   4.8   17.0  62.7    -2.7    392  2.0
  9750    1.7  35.1   245   20   10   8.6   4.7   17.0  62.5    -2.8    365  1.9
  9500    2.4  36.3   240   19   10   8.6   4.7   16.9  62.4    -2.9    339  1.7
  9250    3.0  37.4   235   19   10   8.6   4.7   16.8  62.2    -3.0    312  1.6
  9000    3.7  38.7   230   18    9   8.6   4.7   16.7  62.1    -3.1    285  1.5
  8750    4.3  39.7   230   18    9   8.6   4.7   16.6  61.9    -3.2    259  1.3
  8500    5.0  41.0   225   16    8   8.6   4.7   16.5  61.8    -3.3    232  1.2
  8250    5.6  42.1   225   14    7   8.6   4.7   16.5  61.6    -3.4    205  1.0
  8000    6.2  43.2   215   12    6   8.6   4.7   16.4  61.5    -3.5    179  0.9
  7750    6.9  44.4   210   12    6   8.6   4.7   16.3  61.3    -3.6    152  0.8
  7500    7.5  45.5   200   13    7   8.6   4.7   16.2  61.1    -3.7    125  0.6
  7250    8.2  46.8   195   14    7   8.6   4.7   16.1  61.0    -3.8     99  0.5
  7000    8.8  47.8   185   15    8   8.6   4.7   16.0  60.8    -3.9     72  0.4
  6750    9.5  49.1   185   15    8   8.5   4.7   15.9  60.6    -4.0     45  0.2
  6500   10.1  50.2   175   16    8   8.8   4.8   15.8  60.4    -4.1     19  0.1
  6250   10.7  51.3   170   18    9   7.9   4.3   15.7  60.3    -4.2      M    M
  6000   11.4  52.5   165   20   10  11.3   6.2   15.6  60.1    -4.3      M    M
  5750   12.0  53.6   170   18    9  -1.6  -0.9   15.5  59.9    -4.4      M    M
  5500   11.3  52.3   165   14    7 -11.2  -6.2   14.0  57.1    -5.9      M    M
  5250   11.0  51.8   160   10    5   3.2   1.7   12.9  55.3    -7.0      M    M
  5000   11.3  52.3   140    6    3  -0.4  -0.2   12.5  54.5    -7.4      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...       +1.6        | CAPE...   +40.5    LI...       +0.9
CINH...     0.0    K Index... +13.4        | CINH...   -14.0    K Index... +19.7
                                           |
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 -58.5 -73.3  270  65 33   0.5   0.3 | -57.8 -72.0  265  63 32   1.2   0.6
 45000 -57.7 -71.9  265  87 45   0.5   0.3 | -56.1 -69.0  260  84 43   1.3   0.7
 40000 -57.0 -70.6  265  93 48   0.5   0.3 | -56.3 -69.3  260  98 50  -0.2  -0.1
 38000 -56.3 -69.3  265  89 46   2.0   1.1 | -56.2 -69.2  260  98 50   1.5   0.8
 36000 -55.1 -67.2  265  75 39   1.9   1.1 | -55.1 -67.2  260  83 43   1.5   0.8
 34000 -53.8 -64.8  260  62 32   5.1   2.8 | -54.1 -65.4  255  71 36   5.1   2.8
 32000 -50.4 -58.7  255  57 29   5.6   3.1 | -50.4 -58.7  250  62 32   6.1   3.4
 30000 -46.9 -52.4  250  52 27   7.1   3.9 | -46.7 -52.1  240  56 29   6.8   3.7
 29000 -44.8 -48.6  250  51 26   7.1   3.9 | -44.7 -48.5  240  53 27   6.8   3.7
 28000 -42.7 -44.9  250  51 26   7.1   3.9 | -42.7 -44.9  235  51 26   6.8   3.7
 27000 -40.5 -40.9  250  50 26   7.0   3.8 | -40.7 -41.3  235  48 25   6.6   3.6
 26000 -38.1 -36.6  250  48 25   8.5   4.7 | -38.2 -36.8  235  47 24   9.0   4.9
 25000 -35.6 -32.1  250  45 23   8.5   4.7 | -35.5 -31.9  235  47 24   9.0   5.0
 24000 -33.1 -27.6  250  42 22   8.5   4.7 | -32.8 -27.0  235  46 24   9.1   5.0
 23000 -30.0 -22.0  250  40 20   8.1   4.4 | -30.3 -22.5  235  46 23   8.0   4.4
 22000 -27.6 -17.7  250  38 20   8.1   4.4 | -27.3 -17.1  235  44 23   8.0   4.4
 21000 -25.2 -13.4  250  36 19   8.0   4.4 | -25.0 -13.0  235  43 22   7.7   4.2
 20000 -22.8  -9.0  245  34 18   8.0   4.4 | -22.7  -8.9  230  41 21   7.5   4.1
 19500 -21.6  -6.9  245  33 17   8.0   4.4 | -21.6  -6.9  230  40 21   7.5   4.1
 19000 -20.4  -4.7  240  32 17   8.0   4.4 | -20.5  -4.9  230  40 20   7.5   4.1
 18500 -19.2  -2.6  240  32 16   7.8   4.3 | -19.4  -2.9  230  39 20   7.0   3.9
 18000 -18.1  -0.6  240  31 16   7.5   4.1 | -18.5  -1.3  230  38 19   6.2   3.4
 17500 -17.0   1.4  235  31 16   7.5   4.1 | -17.6   0.3  230  37 19   6.3   3.5
 17000 -15.9   3.4  235  30 16   6.6   3.6 | -16.7   1.9  230  36 19   5.4   2.9
 16500 -14.9   5.2  235  30 16   6.7   3.7 | -15.9   3.4  230  35 18   5.4   3.0
 16000 -13.9   7.0  235  31 16   6.3   3.5 | -15.1   4.8  230  34 18   6.2   3.4
 15500 -13.0   8.6  235  31 16   6.2   3.4 | -14.1   6.6  230  33 17   6.5   3.6
 15000 -12.1  10.2  230  31 16   6.4   3.5 | -13.1   8.4  230  32 16   7.0   3.8
 14500 -11.1  12.0  230  31 16   6.7   3.7 | -12.0  10.4  230  30 16   8.0   4.4
 14000 -10.2  13.6  230  31 16   6.9   3.8 | -10.8  12.6  230  29 15   8.0   4.4
 13500  -9.1  15.6  225  31 16   7.8   4.3 |  -9.5  14.9  230  28 14   8.6   4.7
 13000  -8.0  17.6  225  31 16   7.8   4.3 |  -8.3  17.1  230  27 14   8.6   4.7
 12500  -6.8  19.8  225  30 15   8.2   4.5 |  -7.0  19.4  230  26 13   8.8   4.8
 12000  -5.6  21.9  225  29 15   8.2   4.5 |  -5.7  21.7  225  25 13   8.8   4.8
 11500  -4.4  24.1  225  28 15   7.9   4.3 |  -4.4  24.1  225  24 12   9.0   5.0
 11000  -3.3  26.1  220  27 14   7.9   4.3 |  -3.1  26.4  225  23 12   9.0   5.0
 10500  -2.2  28.0  225  26 13   7.1   3.9 |  -1.8  28.8  225  22 11   7.5   4.1
 10250  -1.6  29.1  225  26 13   7.8   4.3 |  -1.3  29.7  225  21 11   8.5   4.7
 10000  -1.0  30.2  225  25 13  10.5   5.7 |  -0.6  30.9  220  21 11  11.0   6.0
  9750  -0.2  31.6  220  24 12   9.9   5.4 |   0.3  32.5  220  21 11  10.2   5.6
  9500   0.5  32.9  220  23 12   8.2   4.5 |   0.9  33.6  220  20 10   8.7   4.8
  9250   1.1  34.0  225  23 12   8.6   4.7 |   1.6  34.9  220  20 10   9.2   5.0
  9000   1.7  35.1  225  22 11   8.6   4.7 |   2.3  36.1  220  19 10   8.8   4.8
  8750   3.0  37.4  220  20 10   8.4   4.6 |   2.9  37.2  215  20 10   8.9   4.9
  8500   3.6  38.5  220  18  9   8.5   4.7 |   3.6  38.5  215  19 10   9.3   5.1
  8250   4.3  39.7  215  17  9   8.3   4.5 |   4.3  39.7  215  19 10   8.9   4.9
  8000   4.9  40.8  215  16  8   7.7   4.2 |   5.8  42.4  215  17  9  10.2   5.6
  7750   5.4  41.7  210  15  8   7.5   4.1 |   6.5  43.7  215  17  9   9.1   5.0
  7500   6.0  42.8  205  14  7   7.4   4.1 |   7.1  44.8  210  17  9   9.3   5.1
  7250   6.5  43.7  200  13  7   6.6   3.6 |   7.8  46.0  210  17  9   8.2   4.5
  7000   7.0  44.6  195  12  6   6.4   3.5 |   8.4  47.1  210  17  9   9.4   5.2
  6750   7.4  45.3  190  12  6   6.8   3.7 |   9.2  48.6  210  17  9  11.0   6.0
  6500   7.9  46.2  180  11  6   6.3   3.4 |  10.0  50.0  210  16  8  10.6   5.8
  6250   8.4  47.1  170  10  5   6.2   3.4 |  10.8  51.4  210  16  8  11.6   6.4
  6000   8.8  47.8  160  10  5   5.0   2.7 |  11.7  53.1  210  15  8   9.2   5.1
  5750   9.1  48.4  165   8  4   4.1   2.2 |  12.3  54.1  210  14  7  11.5   6.3
  5500   9.8  49.6  150   6  3  20.7  11.3 |  14.5  58.1  210  12  6  59.3  32.5
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     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...   +60.1    LI...       -0.5        | CAPE...   +80.8    LI...       -0.2
CINH...    -3.8    K Index... +23.1        | CINH...   -34.1    K Index... +25.2
                                           |
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 -57.5 -71.5  260  61 32   1.0   0.5 | -57.0 -70.6  255  58 30   1.2   0.6
 45000 -55.9 -68.6  255  82 42   1.1   0.6 | -55.2 -67.4  255  76 39   1.2   0.6
 40000 -55.8 -68.4  255 101 52   0.0   0.0 | -55.0 -67.0  250  98 51  -0.0  -0.0
 38000 -55.5 -67.9  255 103 53   1.6   0.9 | -54.8 -66.6  250 101 52   1.1   0.6
 36000 -54.5 -66.1  250  92 47   1.7   0.9 | -54.1 -65.4  250  88 45   1.1   0.6
 34000 -53.4 -64.1  250  79 41   3.8   2.1 | -53.5 -64.3  250  76 39   1.2   0.7
 32000 -50.3 -58.5  245  69 35   5.0   2.8 | -51.4 -60.5  245  63 32   3.7   2.0
 30000 -47.3 -53.1  240  59 31   6.6   3.6 | -49.1 -56.4  235  51 26   4.7   2.6
 29000 -45.2 -49.4  240  58 30   7.0   3.9 | -46.9 -52.4  235  49 25   8.2   4.5
 28000 -43.1 -45.6  240  56 29   7.0   3.9 | -44.4 -47.9  235  48 25   8.1   4.5
 27000 -41.0 -41.8  235  55 28   6.9   3.8 | -42.0 -43.6  235  47 24   8.2   4.5
 26000 -38.5 -37.3  235  53 27   8.9   4.9 | -38.8 -37.8  235  45 23   8.6   4.7
 25000 -35.9 -32.6  235  51 26   8.9   4.9 | -36.2 -33.2  235  43 22   8.6   4.7
 24000 -33.2 -27.8  235  48 25   8.9   4.9 | -33.6 -28.5  235  41 21   8.7   4.8
 23000 -30.7 -23.3  235  47 24   8.2   4.5 | -31.1 -24.0  235  40 20   8.5   4.7
 22000 -27.7 -17.9  235  47 24   8.1   4.5 | -28.6 -19.5  235  38 20   8.5   4.7
 21000 -25.3 -13.5  230  47 24   7.5   4.1 | -26.0 -14.8  235  37 19   8.5   4.7
 20000 -23.3  -9.9  230  45 23   6.8   3.7 | -23.6 -10.5  230  36 19   8.2   4.5
 19500 -22.2  -8.0  230  44 23   6.8   3.7 | -22.4  -8.3  230  36 19   8.2   4.5
 19000 -21.2  -6.2  230  43 22   6.8   3.7 | -21.1  -6.0  230  36 18   8.2   4.5
 18500 -20.2  -4.4  230  42 22   6.9   3.8 | -19.9  -3.8  225  35 18   8.3   4.6
 18000 -19.2  -2.6  230  40 21   7.2   3.9 | -18.7  -1.7  225  35 18   7.8   4.3
 17500 -18.1  -0.6  225  39 20   7.1   3.9 | -17.6   0.3  225  35 18   7.9   4.3
 17000 -17.1   1.2  225  37 19   7.7   4.2 | -16.4   2.5  220  35 18   7.6   4.2
 16500 -15.9   3.4  225  36 18   7.8   4.3 | -15.3   4.5  220  35 18   7.4   4.1
 16000 -14.8   5.4  225  34 18   7.9   4.3 | -14.2   6.4  220  34 18   7.4   4.1
 15500 -13.6   7.5  225  33 17   8.0   4.4 | -13.2   8.2  215  34 18   7.3   4.0
 15000 -12.4   9.7  220  32 16   8.0   4.4 | -12.1  10.2  215  34 17   7.3   4.0
 14500 -11.3  11.7  220  31 16   8.0   4.4 | -11.0  12.2  215  34 17   8.0   4.4
 14000 -10.1  13.8  220  30 15   8.0   4.4 |  -9.8  14.4  215  33 17   7.9   4.3
 13500  -8.9  16.0  220  29 15   8.5   4.6 |  -8.6  16.5  210  33 17   8.4   4.6
 13000  -7.6  18.3  215  28 14   8.3   4.6 |  -7.4  18.7  210  33 17   8.4   4.6
 12500  -6.3  20.7  215  27 14   9.2   5.1 |  -6.1  21.0  210  32 17   8.4   4.6
 12000  -5.0  23.0  215  27 14   9.1   5.0 |  -4.9  23.2  210  32 16   8.4   4.6
 11500  -3.6  25.5  215  26 13   9.3   5.1 |  -3.6  25.5  210  31 16   8.6   4.7
 11000  -2.2  28.0  215  26 13   9.4   5.2 |  -2.3  27.9  210  31 16   8.7   4.8
 10500  -0.9  30.4  215  25 13   8.0   4.4 |  -1.1  30.0  210  30 15   7.6   4.1
 10250  -0.3  31.5  215  24 13   9.2   5.0 |  -0.6  30.9  210  29 15   7.8   4.3
 10000   0.5  32.9  215  25 13  11.5   6.3 |   0.1  32.2  210  29 15   9.8   5.4
  9750   1.4  34.5  215  25 13  10.8   5.9 |   0.8  33.4  210  29 15   9.9   5.4
  9500   2.1  35.8  215  25 13   9.6   5.3 |   1.5  34.7  210  28 15   8.8   4.8
  9250   2.8  37.0  215  24 12   9.8   5.4 |   2.2  36.0  215  27 14   8.4   4.6
  9000   3.6  38.5  215  24 12  10.0   5.5 |   2.8  37.0  215  27 14   8.3   4.5
  8750   4.3  39.7  215  24 13  10.2   5.6 |   4.0  39.2  215  26 13   8.9   4.9
  8500   5.8  42.4  215  24 12  10.2   5.6 |   4.7  40.5  215  25 13   9.3   5.1
  8250   6.6  43.9  215  23 12   9.6   5.3 |   5.4  41.7  215  25 13   8.1   4.5
  8000   7.3  45.1  215  23 12   9.6   5.3 |   5.9  42.6  220  24 12   7.6   4.2
  7750   8.0  46.4  215  23 12  10.1   5.5 |   6.5  43.7  220  23 12   8.4   4.6
  7500   8.8  47.8  215  22 12  10.5   5.7 |   7.1  44.8  220  22 11   8.3   4.6
  7250   9.5  49.1  215  22 11   8.6   4.7 |   7.8  46.0  220  21 11   8.0   4.4
  7000  10.1  50.2  215  22 11   8.9   4.9 |   8.3  46.9  220  21 11   8.5   4.7
  6750  10.9  51.6  215  21 11  11.1   6.1 |   9.0  48.2  220  20 10   9.3   5.1
  6500  11.7  53.1  215  20 10  10.7   5.9 |   9.7  49.5  225  18  9   8.9   4.9
  6250  12.5  54.5  215  20 10  10.7   5.9 |  10.3  50.5  225  17  9   9.7   5.3
  6000  13.4  56.1  215  19 10  14.6   8.0 |  11.1  52.0  225  17  9  11.9   6.5
  5750  14.8  58.6  215  17  9  22.0  12.0 |  12.1  53.8  225  15  8  13.3   7.3
  5500  16.1  61.0  215  15  8   8.6   4.7 |  13.0  55.4  225  13  7  11.6   6.4
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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.

CINH (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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