Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281307
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
707 AM MDT Thursday, March 28, 2024

This forecast is for Thursday, March 28, 2024:

If the trigger temperature of 52.3 F/11.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 523 ft/min (2.7 m/s)
   Maximum height of thermals.................. 14072 ft MSL (9233 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1300 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................. 12687 ft MSL (7848 ft AGL)
Thermal soaring outlook for Friday 03/29....... Good

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

Remarks...

Sunrise/Sunset.................... 07:03:32 / 19:34:20 MDT
Total possible sunshine........... 12 hr 30 min 48 sec (750 min 48 sec)
Altitude of sun at 13:18:56 MDT... 54.03 degrees

Upper air data from rawinsonde observation taken on 03/28/2024 at 0600 MDT

Freezing level.................. 8440 ft MSL (3601 ft AGL)
Convective condensation level... 18803 ft MSL (13964 ft AGL)
Lifted condensation level....... 16915 ft MSL (12076 ft AGL)
Lifted index.................... +4.6
K index......................... -7.3

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  -57.9 -72.2   250   56   29   1.6   0.9  107.8 226.0    51.2      M    M
 45000  -60.6 -77.1   265   61   31  -6.1  -3.4   78.2 172.8    36.9      M    M
 40000  -60.8 -77.4   265   81   42 -14.1  -7.7   54.5 130.1    24.2      M    M
 38000  -64.7 -84.5   270   80   41   4.6   2.5   38.4 101.1    14.2      M    M
 36000  -60.8 -77.4   265   87   45   6.4   3.5   35.5  95.9    12.6      M    M
 34000  -55.8 -68.4   265   85   44   8.5   4.6   34.3  93.7    12.1      M    M
 32000  -50.9 -59.6   265   76   39   8.8   4.8   32.9  91.3    11.4      M    M
 30000  -45.9 -50.6   265   71   37   8.5   4.7   31.9  89.3    10.9      M    M
 29000  -43.3 -45.9   265   73   37   8.6   4.7   31.4  88.5    10.7      M    M
 28000  -40.9 -41.6   265   67   35   7.8   4.3   30.7  87.2    10.3      M    M
 27000  -38.6 -37.5   270   62   32   7.7   4.2   29.9  85.8     9.8      M    M
 26000  -36.1 -33.0   265   54   28   7.8   4.3   29.4  84.9     9.5      M    M
 25000  -33.7 -28.7   270   53   27   8.1   4.4   28.7  83.7     9.1      M    M
 24000  -31.7 -25.1   265   52   27   8.6   4.7   27.6  81.6     8.2      M    M
 23000  -29.7 -21.5   260   51   26   6.4   3.5   26.4  79.5     7.4      M    M
 22000  -27.6 -17.7   265   48   25   7.4   4.1   25.5  77.9     6.7      M    M
 21000  -25.3 -13.5   265   49   25   7.3   4.0   24.6  76.3     6.1      M    M
 20000  -22.3  -8.1   265   41   21   8.3   4.5   23.9  75.0     5.5      M    M
 19500  -21.1  -6.0   260   39   20   8.2   4.5   23.6  74.5     5.3      M    M
 19000  -19.9  -3.8   260   42   22   8.1   4.4   23.3  74.0     5.1      M    M
 18500  -18.6  -1.5   260   39   20   7.5   4.1   23.1  73.6     4.9      M    M
 18000  -17.7   0.1   255   37   19   5.7   3.1   22.4  72.4     4.3      M    M
 17500  -16.7   1.9   255   37   19   8.8   4.8   22.0  71.5     3.9      M    M
 17000  -15.6   3.9   255   33   17   6.1   3.4   21.6  70.8     3.6      M    M
 16500  -14.7   5.5   255   31   16   6.3   3.5   21.0  69.7     3.0      M    M
 16000  -13.5   7.7   255   27   14   7.3   4.0   20.4  68.8     2.8      M    M
 15500  -12.6   9.3   245   24   12   4.7   2.6   19.9  67.8     2.3      M    M
 15000  -11.9  10.6   225   28   14   4.4   2.4   19.0  66.1     1.5      M    M
 14500  -11.3  11.7   235   26   13   4.4   2.4   18.1  64.5     0.7      M    M
 14000  -10.7  12.7   230   26   13   4.4   2.4   17.2  62.9    -0.2    715  3.6
 13500  -10.0  14.0   225   28   14   3.5   1.9   16.3  61.3    -1.1    682  3.5
 13000  -10.1  13.8   235   31   16   0.9   0.5   14.7  58.5    -2.6    668  3.4
 12500   -9.1  15.6   240   30   15   8.4   4.6   14.1  57.4    -3.1    625  3.2
 12000   -7.9  17.8   240   29   15   8.2   4.5   13.9  57.0    -3.4    574  2.9
 11500   -6.7  19.9   240   26   13   8.2   4.5   13.6  56.5    -3.6    522  2.7
 11000   -5.5  22.1   245   23   12   8.2   4.5   13.4  56.1    -3.9    471  2.4
 10500   -4.2  24.4   240   20   10   8.2   4.5   13.1  55.6    -4.2    419  2.1
 10250   -3.6  25.5   235   18    9   8.3   4.5   13.0  55.4    -4.3    393  2.0
 10000   -3.0  26.6   235   18    9   7.0   3.9   12.8  55.1    -4.4    368  1.9
  9750   -2.6  27.3   245   18    9   6.0   3.3   12.6  54.6    -4.7    347  1.8
  9500   -2.1  28.2   235   18    9   6.3   3.5   12.3  54.1    -5.0    325  1.7
  9250   -1.6  29.1   235   18   10   6.2   3.4   12.0  53.7    -5.2    304  1.5
  9000   -1.1  30.0   235   19   10   6.2   3.4   11.8  53.2    -5.5    282  1.4
  8750   -0.7  30.7   240   17    9   6.2   3.4   11.5  52.7    -5.8    260  1.3
  8500   -0.2  31.6   235   18    9   6.2   3.4   11.2  52.2    -6.1    239  1.2
  8250    0.3  32.5   230   21   11   6.2   3.4   10.9  51.7    -6.3    217  1.1
  8000    0.8  33.4   220   20   10   6.2   3.4   10.7  51.2    -6.6    196  1.0
  7750    1.2  34.2   210   19   10   6.2   3.4   10.4  50.7    -6.9    174  0.9
  7500    1.7  35.1   195   18    9   6.3   3.4   10.1  50.2    -7.2    152  0.8
  7250    2.2  36.0   175   19   10   6.2   3.4    9.8  49.7    -7.4    131  0.7
  7000    2.7  36.9   165   21   11   6.3   3.4    9.6  49.2    -7.7    109  0.6
  6750    3.1  37.6   160   22   12   6.8   3.8    9.3  48.8    -8.0     87  0.4
  6500    3.7  38.7   155   24   12   7.3   4.0    9.1  48.4    -8.2     64  0.3
  6250    4.2  39.6   155   25   13   7.1   3.9    8.9  48.1    -8.4     41  0.2
  6000    4.7  40.5   145   24   12   7.6   4.2    8.7  47.7    -8.7     18  0.1
  5750    5.2  41.4   145   24   12   5.8   3.2    8.5  47.4    -8.9      M    M
  5500    5.2  41.4   145   22   12 -10.8  -5.9    7.8  46.0    -9.7      M    M
  5250    4.0  39.2   145   24   12  -9.6  -5.2    5.9  42.6   -11.6     16  0.1
  5000    4.4  39.9   140   27   14  18.0   9.9    5.5  41.9   -12.0      M    M

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

           03/28/2024 at 0900 MDT          |       03/28/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.9        | CAPE...     0.0    LI...       +4.0
CINH...     0.0    K Index...  +9.7        | CINH...     0.0    K Index... +14.6
                                           |
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 -59.8 -75.6  255  56 29  -0.2  -0.1 | -59.6 -75.3  255  56 29  -0.4  -0.2
 45000 -60.1 -76.2  260  68 35  -0.3  -0.2 | -60.2 -76.4  260  72 37  -0.5  -0.3
 40000 -62.5 -80.5  265  85 44  -1.7  -0.9 | -62.0 -79.6  260  90 46  -1.3  -0.7
 38000 -62.0 -79.6  265  87 45   4.7   2.6 | -61.5 -78.7  260  93 48   4.3   2.3
 36000 -59.3 -74.7  265  82 42   4.6   2.5 | -59.0 -74.2  255  88 46   4.2   2.3
 34000 -56.2 -69.2  260  78 40   8.9   4.9 | -56.2 -69.2  255  84 43   8.7   4.8
 32000 -51.0 -59.8  260  75 39   8.7   4.8 | -50.9 -59.6  255  80 41   8.8   4.8
 30000 -45.8 -50.4  260  73 37   7.7   4.2 | -45.7 -50.3  255  76 39   8.0   4.4
 29000 -43.5 -46.3  260  70 36   7.8   4.3 | -43.3 -45.9  255  74 38   8.0   4.4
 28000 -41.1 -42.0  260  67 35   7.8   4.3 | -40.9 -41.6  255  72 37   8.0   4.4
 27000 -38.8 -37.8  260  65 33   7.9   4.3 | -38.6 -37.5  250  71 36   8.0   4.4
 26000 -36.6 -33.9  260  61 32   7.1   3.9 | -36.3 -33.3  250  68 35   7.3   4.0
 25000 -34.5 -30.1  260  58 30   7.2   3.9 | -34.1 -29.4  250  65 34   7.3   4.0
 24000 -32.3 -26.1  260  55 28   7.1   3.9 | -31.9 -25.4  250  63 32   7.3   4.0
 23000 -29.4 -20.9  260  53 27   8.0   4.4 | -29.2 -20.6  250  60 31   7.4   4.1
 22000 -27.1 -16.8  255  51 26   8.0   4.4 | -27.0 -16.6  250  57 29   7.4   4.1
 21000 -24.7 -12.5  255  49 25   7.7   4.2 | -24.8 -12.6  250  55 28   7.3   4.0
 20000 -22.4  -8.3  255  46 24   7.6   4.2 | -22.7  -8.9  245  52 27   7.2   4.0
 19500 -21.3  -6.3  255  45 23   7.6   4.2 | -21.6  -6.9  245  50 26   7.2   4.0
 19000 -20.2  -4.4  255  44 23   7.7   4.2 | -20.5  -4.9  245  49 25   7.2   4.0
 18500 -19.1  -2.4  255  43 22   7.3   4.0 | -19.5  -3.1  245  47 24   7.0   3.8
 18000 -18.0  -0.4  250  42 22   7.1   3.9 | -18.5  -1.3  245  46 24   6.8   3.8
 17500 -17.0   1.4  250  41 21   7.1   3.9 | -17.5   0.5  245  45 23   6.9   3.8
 17000 -15.9   3.4  250  40 20   6.7   3.6 | -16.5   2.3  245  44 22   6.3   3.5
 16500 -14.9   5.2  250  39 20   6.7   3.7 | -15.6   3.9  245  42 22   6.4   3.5
 16000 -14.0   6.8  245  38 19   5.9   3.2 | -14.6   5.7  245  41 21   6.3   3.5
 15500 -13.1   8.4  245  37 19   5.8   3.2 | -13.7   7.3  245  40 20   6.3   3.5
 15000 -12.2  10.0  245  36 18   5.3   2.9 | -12.7   9.1  245  38 20   6.0   3.3
 14500 -11.5  11.3  240  35 18   4.9   2.7 | -11.9  10.6  245  37 19   5.6   3.1
 14000 -10.8  12.6  240  34 18   5.0   2.8 | -11.1  12.0  240  35 18   5.6   3.1
 13500 -10.0  14.0  240  33 17   5.3   2.9 | -10.2  13.6  240  34 17   5.6   3.1
 13000  -9.3  15.3  235  33 17   5.6   3.1 |  -9.4  15.1  240  33 17   5.8   3.2
 12500  -8.3  17.1  235  32 16   6.9   3.8 |  -8.5  16.7  235  31 16   6.9   3.8
 12000  -7.3  18.9  235  31 16   6.9   3.8 |  -7.5  18.5  235  30 16   6.9   3.8
 11500  -6.3  20.7  230  30 15   7.1   3.9 |  -6.3  20.7  230  28 15   7.9   4.3
 11000  -5.2  22.6  230  28 14   7.0   3.9 |  -5.2  22.6  225  27 14   7.7   4.2
 10500  -4.2  24.4  230  26 14   7.1   3.9 |  -4.1  24.6  225  24 13   7.0   3.8
 10250  -3.6  25.5  230  25 13   6.7   3.7 |  -3.6  25.5  225  23 12   7.3   4.0
 10000  -3.1  26.4  230  24 13   8.2   4.5 |  -3.0  26.6  220  22 12  10.0   5.5
  9750  -2.4  27.7  225  24 13   8.1   4.5 |  -2.2  28.0  220  22 11  10.1   5.5
  9500  -1.9  28.6  220  24 12   6.8   3.7 |  -1.5  29.3  215  22 11   8.4   4.6
  9250  -1.4  29.5  220  23 12   6.6   3.6 |  -0.9  30.4  215  21 11   8.9   4.9
  9000  -0.9  30.4  215  23 12   8.7   4.8 |  -0.2  31.6  210  20 10   8.5   4.7
  8750  -0.1  31.8  220  22 11   8.3   4.6 |   0.4  32.7  215  18  9   9.0   4.9
  8500   0.3  32.5  215  21 11   5.7   3.1 |   1.8  35.2  210  18  9   9.4   5.1
  8250   1.3  34.3  210  20 11   7.4   4.0 |   2.5  36.5  205  17  9   9.7   5.3
  8000   1.9  35.4  210  21 11   6.4   3.5 |   3.3  37.9  210  16  8   9.7   5.3
  7750   2.3  36.1  205  19 10   5.3   2.9 |   4.0  39.2  205  16  8   9.6   5.3
  7500   2.7  36.9  200  18  9   5.3   2.9 |   4.7  40.5  205  16  8   9.5   5.2
  7250   3.0  37.4  195  19 10   4.7   2.6 |   5.4  41.7  205  15  8   9.2   5.0
  7000   3.4  38.1  190  19 10   4.8   2.6 |   6.1  43.0  205  14  7   9.9   5.4
  6750   3.7  38.7  180  17  9   4.5   2.5 |   6.9  44.4  205  14  7  10.7   5.8
  6500   4.0  39.2  175  15  8   3.8   2.1 |   7.7  45.9  200  14  7  10.7   5.8
  6250   4.3  39.7  170  14  7   3.0   1.7 |   8.5  47.3  200  13  7  12.0   6.6
  6000   4.6  40.3  160  14  7   4.7   2.6 |   9.3  48.7  200  12  6   8.1   4.4
  5750   5.1  41.2  160  10  5   9.3   5.1 |   9.8  49.6  200  12  6   9.7   5.3
  5500   5.7  42.3  150   8  4   6.7   3.7 |  12.4  54.3  200  10  5  78.0  42.8
  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

           03/28/2024 at 1500 MDT          |       03/28/2024 at 1800 MDT
                                           |
CAPE...    +9.9    LI...       +1.4        | CAPE...   +38.1    LI...       -0.2
CINH...    -1.5    K Index... +19.5        | CINH...    -4.5    K Index... +20.5
                                           |
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 -59.5 -75.1  255  56 29  -0.6  -0.3 | -59.6 -75.3  255  57 29  -0.9  -0.5
 45000 -60.4 -76.7  255  75 39  -0.6  -0.3 | -60.9 -77.6  255  76 39  -0.9  -0.5
 40000 -62.2 -80.0  260  99 51  -1.3  -0.7 | -62.7 -80.9  260 103 53  -1.2  -0.6
 38000 -61.8 -79.2  260 106 54   5.1   2.8 | -62.0 -79.6  260 111 57   5.8   3.2
 36000 -58.3 -72.9  260 102 53   5.2   2.9 | -58.5 -73.3  260 111 57   5.8   3.2
 34000 -55.0 -67.0  255  99 51   7.2   3.9 | -54.9 -66.8  265 112 58   6.8   3.7
 32000 -50.6 -59.1  255  93 48   7.3   4.0 | -50.4 -58.7  260 105 54   7.5   4.1
 30000 -46.2 -51.2  255  86 44   8.5   4.7 | -45.9 -50.6  260  99 51   7.7   4.2
 29000 -43.7 -46.7  255  83 43   8.3   4.6 | -43.7 -46.7  255  94 48   7.5   4.1
 28000 -41.2 -42.2  255  79 41   8.3   4.6 | -41.4 -42.5  255  88 46   7.5   4.1
 27000 -38.7 -37.7  255  76 39   8.5   4.6 | -38.6 -37.5  255  82 42   7.5   4.1
 26000 -36.5 -33.7  255  74 38   7.3   4.0 | -36.4 -33.5  255  77 40   7.2   3.9
 25000 -34.3 -29.7  255  71 37   7.3   4.0 | -34.3 -29.7  255  73 37   7.2   3.9
 24000 -32.1 -25.8  250  69 36   7.4   4.0 | -32.1 -25.8  255  68 35   7.2   4.0
 23000 -30.0 -22.0  250  66 34   6.9   3.8 | -30.1 -22.2  255  64 33   6.8   3.7
 22000 -27.4 -17.3  250  62 32   6.9   3.8 | -28.1 -18.6  255  61 31   6.8   3.7
 21000 -25.4 -13.7  250  59 30   7.1   3.9 | -26.0 -14.8  255  57 29   6.9   3.8
 20000 -23.2  -9.8  250  55 28   7.2   3.9 | -23.9 -11.0  255  53 27   7.1   3.9
 19500 -22.2  -8.0  250  54 28   7.2   3.9 | -22.9  -9.2  255  51 26   7.1   3.9
 19000 -21.1  -6.0  245  52 27   7.2   3.9 | -21.8  -7.2  255  49 25   7.1   3.9
 18500 -20.1  -4.2  245  50 26   6.9   3.8 | -20.8  -5.4  255  47 24   7.1   3.9
 18000 -19.1  -2.4  245  49 25   6.7   3.7 | -19.7  -3.5  250  45 23   7.3   4.0
 17500 -18.1  -0.6  245  47 24   6.7   3.7 | -18.6  -1.5  250  43 22   7.2   4.0
 17000 -17.1   1.2  245  45 23   6.4   3.5 | -17.5   0.5  245  42 21   7.4   4.1
 16500 -16.2   2.8  245  43 22   6.4   3.5 | -16.5   2.3  245  40 21   7.4   4.1
 16000 -15.3   4.5  240  40 21   6.5   3.6 | -15.4   4.3  240  39 20   7.7   4.2
 15500 -14.3   6.3  240  38 20   6.6   3.6 | -14.2   6.4  240  38 19   7.9   4.3
 15000 -13.4   7.9  240  36 19   6.8   3.8 | -13.0   8.6  235  37 19   8.0   4.4
 14500 -12.3   9.9  235  34 18   7.2   3.9 | -11.9  10.6  235  36 19   8.2   4.5
 14000 -11.3  11.7  235  33 17   7.4   4.1 | -10.6  12.9  230  36 18   8.2   4.5
 13500 -10.1  13.8  235  31 16   8.1   4.5 |  -9.4  15.1  230  35 18   9.1   5.0
 13000  -8.9  16.0  230  30 16   8.2   4.5 |  -8.0  17.6  230  34 18   9.0   5.0
 12500  -7.6  18.3  230  29 15   8.7   4.8 |  -6.6  20.1  225  34 17   9.4   5.2
 12000  -6.4  20.5  230  28 14   8.7   4.8 |  -5.2  22.6  225  33 17   9.4   5.1
 11500  -5.0  23.0  230  27 14   9.6   5.3 |  -3.8  25.2  225  33 17   9.5   5.2
 11000  -3.5  25.7  225  26 14   9.5   5.2 |  -2.4  27.7  225  32 16   9.6   5.3
 10500  -2.2  28.0  225  25 13   7.9   4.3 |  -1.1  30.0  225  31 16   7.7   4.2
 10250  -1.6  29.1  230  25 13   9.2   5.0 |  -0.5  31.1  225  30 15   8.7   4.8
 10000  -0.8  30.6  225  25 13  11.6   6.4 |   0.2  32.4  225  29 15  11.1   6.1
  9750   0.0  32.0  225  25 13  10.5   5.8 |   1.1  34.0  225  29 15  10.6   5.8
  9500   0.7  33.3  230  24 12   9.1   5.0 |   1.8  35.2  225  29 15   9.2   5.1
  9250   1.4  34.5  230  24 12   9.4   5.2 |   3.2  37.8  225  27 14   9.8   5.4
  9000   2.1  35.8  230  23 12   9.7   5.3 |   4.0  39.2  225  27 14   9.7   5.3
  8750   2.9  37.2  225  23 12   9.9   5.4 |   4.7  40.5  225  27 14   9.4   5.2
  8500   4.3  39.7  225  22 12   9.8   5.4 |   5.4  41.7  225  26 13   9.3   5.1
  8250   5.1  41.2  225  22 11   9.9   5.5 |   6.1  43.0  225  26 13  10.3   5.6
  8000   5.8  42.4  230  21 11   9.9   5.4 |   6.9  44.4  225  25 13  10.2   5.6
  7750   6.5  43.7  230  21 11   9.7   5.3 |   7.6  45.7  225  24 12   9.0   4.9
  7500   7.3  45.1  225  20 11   9.6   5.3 |   8.3  46.9  225  23 12   9.4   5.2
  7250   8.0  46.4  230  20 10   9.1   5.0 |   9.0  48.2  225  23 12   8.6   4.7
  7000   8.6  47.5  230  20 10   9.7   5.3 |   9.6  49.3  225  23 12   9.1   5.0
  6750   9.4  48.9  230  19 10  10.2   5.6 |  10.3  50.5  225  21 11   9.9   5.4
  6500  10.2  50.4  225  18  9  10.5   5.7 |  11.1  52.0  225  20 10  10.1   5.5
  6250  11.0  51.8  230  18  9  11.9   6.5 |  11.9  53.4  225  19 10  11.7   6.4
  6000  11.8  53.2  230  17  9   8.4   4.6 |  12.7  54.9  225  19 10   9.2   5.1
  5750  12.3  54.1  230  15  8   8.2   4.5 |  13.2  55.8  225  17  9   6.5   3.6
  5500  14.3  57.7  230  14  7  59.2  32.5 |  14.4  57.9  225  14  7  34.1  18.7
  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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