Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251325
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0625 MST Thursday, December 25, 2014

This forecast is for Thursday, December 25, 2014:

If the trigger temperature of 45.2 F/7.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5589 ft MSL (750 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Friday 12/26....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:31:28 / 16:57:16 MST
Total possible sunshine........... 9 hr 25 min 48 sec (565 min 48 sec)
Altitude of sun at 12:14:20 MST... 27.57 degrees

Upper air data from rawinsonde observation taken on 12/25/2014 at 0500 MST

Freezing level.................. 5850 ft MSL (1011 ft AGL)
Additional freezing level....... 6993 ft MSL (2154 ft AGL)
Convective condensation level... 14796 ft MSL (9957 ft AGL)
Lifted condensation level....... 9397 ft MSL (4558 ft AGL)
Lifted index.................... +11.2
K index......................... +15.6

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  -54.7 -66.5   245   39   20   0.7   0.4  111.6 232.8    62.4      M    M
 45000  -53.2 -63.8   230   45   23  -4.2  -2.3   89.2 192.6    53.1      M    M
 40000  -51.2 -60.2   250   48   25   2.3   1.3   68.9 156.1    43.6      M    M
 38000  -49.8 -57.6   250   62   32   2.8   1.5   61.1 142.0    39.7      M    M
 36000  -50.2 -58.4   245   68   35   2.7   1.5   51.8 125.2    34.4      M    M
 34000  -48.9 -56.0   240   75   38   8.2   4.5   45.3 113.5    30.7      M    M
 32000  -47.6 -53.7   235   76   39  -1.1  -0.6   38.9 102.0    26.9      M    M
 30000  -47.8 -54.0   230   74   38   4.9   2.7   30.6  87.2    21.5      M    M
 29000  -46.7 -52.1   225   76   39  -4.8  -2.6   28.1  82.6    19.9      M    M
 28000  -45.7 -50.3   230   63   32   4.3   2.4   25.5  78.0    18.2      M    M
 27000  -45.0 -49.0   235   50   26   1.7   0.9   22.7  72.9    16.2      M    M
 26000  -43.1 -45.6   230   48   25  10.2   5.6   21.4  70.5    15.4      M    M
 25000  -40.1 -40.2   225   47   24  10.1   5.5   21.6  70.9    15.7      M    M
 24000  -37.1 -34.8   225   46   24   9.0   5.0   21.7  71.0    16.0      M    M
 23000  -34.5 -30.1   225   42   22   8.9   4.9   21.3  70.3    15.8      M    M
 22000  -31.7 -25.1   225   40   21   9.7   5.3   21.1  70.0    15.9      M    M
 21000  -29.2 -20.6   230   42   22   8.1   4.5   20.6  69.1    15.7      M    M
 20000  -26.1 -15.0   230   45   23   8.2   4.5   20.0  68.0    15.3      M    M
 19500  -24.9 -12.8   235   48   25   8.2   4.5   19.7  67.4    15.1      M    M
 19000  -23.7 -10.7   235   50   26   8.2   4.5   19.4  66.9    15.0      M    M
 18500  -22.5  -8.5   240   49   25   8.2   4.5   19.1  66.3    14.8      M    M
 18000  -21.3  -6.3   240   48   25   7.9   4.4   18.8  65.8    14.6      M    M
 17500  -20.1  -4.2   245   45   23   7.7   4.2   18.4  65.1    14.3      M    M
 17000  -19.0  -2.2   245   41   21   7.7   4.2   18.0  64.5    14.1      M    M
 16500  -17.9  -0.2   250   38   20   7.7   4.2   17.7  63.9    13.9      M    M
 16000  -16.7   1.9   255   36   18   7.7   4.2   17.4  63.3    13.6      M    M
 15500  -15.6   3.9   255   33   17   6.9   3.8   17.0  62.7    13.4      M    M
 15000  -14.7   5.5   250   31   16   5.6   3.1   16.4  61.5    12.8      M    M
 14500  -13.9   7.0   250   28   15   4.4   2.4   15.7  60.3    12.3      M    M
 14000  -13.7   7.3   245   27   14  -0.7  -0.4   14.3  57.7    11.1      M    M
 13500  -13.4   7.9   240   34   17   6.0   3.3   13.0  55.4    10.0      M    M
 13000  -12.4   9.7   240   41   21   6.6   3.6   12.5  54.6     9.6      M    M
 12500  -11.4  11.5   240   35   18   5.0   2.8   12.0  53.7     9.2      M    M
 12000  -11.0  12.2   240   30   15   2.0   1.1   10.9  51.6     8.1      M    M
 11500  -10.7  12.7   240   23   12   1.7   0.9    9.6  49.3     7.0      M    M
 11000  -10.2  13.6   235   16    8   7.1   3.9    8.6  47.5     6.1      M    M
 10500   -9.0  15.8   245   15    8   8.0   4.4    8.4  47.0     5.9      M    M
 10250   -8.3  17.1   255   14    7   8.1   4.4    8.2  46.8     5.8      M    M
 10000   -7.7  18.1   260   14    7   8.1   4.5    8.1  46.6     5.7      M    M
  9750   -7.1  19.2   260   14    7   8.0   4.4    8.0  46.4     5.6      M    M
  9500   -6.5  20.3   260   14    7   8.6   4.7    7.8  46.1     5.5      M    M
  9250   -5.8  21.6   255   12    6   9.2   5.0    7.8  46.0     5.5      M    M
  9000   -5.2  22.6   240    9    5   9.0   5.0    7.7  45.9     5.4      M    M
  8750   -4.5  23.9   225    9    5   9.1   5.0    7.7  45.8     5.4      M    M
  8500   -3.8  25.2   215   10    5   9.0   4.9    7.6  45.7     5.4      M    M
  8250   -3.1  26.4   205   12    6   8.3   4.6    7.6  45.6     5.3      M    M
  8000   -2.5  27.5   195   14    7   7.9   4.3    7.4  45.4     5.2      M    M
  7750   -1.9  28.6   190   15    8   8.0   4.4    7.3  45.1     5.1      M    M
  7500   -1.3  29.7   180   16    8   8.0   4.4    7.2  44.9     4.9      M    M
  7250   -0.8  30.6   175   17    9   8.0   4.4    7.0  44.6     4.8      M    M
  7000   -0.2  31.6   170   19   10   7.9   4.3    6.9  44.4     4.7      M    M
  6750    0.4  32.7   170   20   10   8.4   4.6    6.8  44.2     4.6      M    M
  6500    1.0  33.8   165   22   11   6.5   3.6    6.6  43.9     4.5      M    M
  6250    1.4  34.5   165   23   12   4.1   2.3    6.3  43.3     4.1      M    M
  6000    1.3  34.3   165   25   13 -12.9  -7.1    5.4  41.7     3.3      M    M
  5750   -0.1  31.8   165   22   11 -15.0  -8.2    3.2  37.8     1.1      M    M
  5500   -0.6  30.9   160   17    9  -2.6  -1.4    2.0  35.6    -0.0     46  0.2
  5250   -0.9  30.4   160   12    6  -4.2  -2.3    1.0  33.7    -1.1     48  0.2
  5000   -1.0  30.2   150    7    4   4.0   2.2    0.2  32.3    -1.9     43  0.2

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

           12/25/2014 at 0800 MST          |       12/25/2014 at 1100 MST
                                           |
K index... +15.4  LI... +3.3               | K index... +16.2  LI... +4.4
CAPE... 0.0  CIN... -0.8                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -55.0 -67.0  255  19 10   2.4   1.3 | -55.6 -68.1  240  25 13   2.7   1.5
 45000 -51.4 -60.5  235  36 19   2.4   1.3 | -51.4 -60.5  235  45 23   2.7   1.5
 40000 -48.9 -56.0  250  39 20   1.4   0.8 | -48.2 -54.8  230  32 17   1.9   1.0
 38000 -48.0 -54.4  255  42 21   1.8   1.0 | -47.2 -53.0  230  29 15   1.2   0.7
 36000 -46.9 -52.4  245  50 26   1.8   1.0 | -46.4 -51.5  230  41 21   1.3   0.7
 34000 -45.8 -50.4  240  60 31   1.7   1.0 | -45.6 -50.1  230  53 27   1.3   0.7
 32000 -46.2 -51.2  235  63 32  -1.6  -0.9 | -45.8 -50.4  230  57 29  -1.0  -0.6
 30000 -47.2 -53.0  230  63 32  -1.5  -0.8 | -46.4 -51.5  230  57 29  -1.0  -0.5
 29000 -46.8 -52.2  230  61 32   5.3   2.9 | -46.2 -51.2  230  57 29   4.4   2.4
 28000 -45.3 -49.5  230  58 30   5.1   2.8 | -44.9 -48.8  230  57 29   4.1   2.3
 27000 -43.8 -46.8  230  54 28   5.1   2.8 | -43.7 -46.7  230  57 30   4.1   2.3
 26000 -42.3 -44.1  230  51 26   6.1   3.4 | -42.5 -44.5  230  57 30   4.6   2.5
 25000 -40.1 -40.2  230  48 25   7.4   4.1 | -40.8 -41.4  230  49 25   5.6   3.1
 24000 -37.8 -36.0  235  45 23   7.4   4.1 | -39.1 -38.4  225  41 21   5.7   3.1
 23000 -35.6 -32.1  235  42 22   7.4   4.1 | -37.4 -35.3  215  33 17   6.6   3.6
 22000 -32.8 -27.0  230  40 21   7.5   4.1 | -34.0 -29.2  215  35 18   9.6   5.3
 21000 -30.6 -23.1  220  39 20   7.5   4.1 | -31.1 -24.0  215  38 19   9.6   5.3
 20000 -28.2 -18.8  220  39 20   8.1   4.4 | -28.4 -19.1  220  39 20   7.6   4.2
 19500 -27.0 -16.6  220  39 20   8.1   4.4 | -27.3 -17.1  220  38 20   7.7   4.2
 19000 -25.8 -14.4  215  40 20   8.1   4.4 | -26.2 -15.2  220  38 19   7.7   4.2
 18500 -24.6 -12.3  215  40 21   8.1   4.5 | -25.0 -13.0  225  37 19   7.7   4.2
 18000 -23.4 -10.1  215  41 21   8.3   4.6 | -23.9 -11.0  225  36 19   7.6   4.2
 17500 -22.1  -7.8  215  41 21   8.9   4.9 | -22.8  -9.0  225  35 18   7.1   3.9
 17000 -20.8  -5.4  215  41 21   9.0   4.9 | -21.8  -7.2  225  34 17   7.1   3.9
 16500 -19.5  -3.1  215  41 21   8.5   4.7 | -20.7  -5.3  220  33 17   7.4   4.1
 16000 -18.2  -0.8  215  40 21   8.5   4.7 | -19.6  -3.3  220  31 16   7.4   4.1
 15500 -17.0   1.4  220  39 20   7.5   4.1 | -18.5  -1.3  215  30 16   6.3   3.5
 15000 -16.0   3.2  225  40 20   6.9   3.8 | -17.7   0.1  215  28 14   5.4   3.0
 14500 -15.0   5.0  225  40 21   6.6   3.6 | -16.9   1.6  210  25 13   5.0   2.7
 14000 -14.1   6.6  230  38 20   6.0   3.3 | -16.3   2.7  205  24 12   4.0   2.2
 13500 -13.2   8.2  235  37 19   5.6   3.0 | -15.7   3.7  205  22 11   4.1   2.2
 13000 -12.7   9.1  235  34 18   2.4   1.3 | -15.0   5.0  205  20 10   4.9   2.7
 12500 -12.3   9.9  240  31 16   2.6   1.4 | -14.3   6.3  215  19 10   4.9   2.7
 12000 -11.8  10.8  240  28 15   3.5   1.9 | -13.4   7.9  215  18  9   6.3   3.5
 11500 -11.3  11.7  245  26 13   3.5   1.9 | -12.5   9.5  220  18  9   6.2   3.4
 11000 -10.7  12.7  245  25 13   4.6   2.5 | -11.6  11.1  220  19 10   5.9   3.2
 10500 -10.1  13.8  245  24 12   4.8   2.7 | -10.8  12.6  225  21 11   6.1   3.3
 10250  -9.7  14.5  245  24 12   6.6   3.6 | -10.3  13.5  225  22 11   6.7   3.7
 10000  -9.1  15.6  240  24 13   7.1   3.9 |  -9.8  14.4  220  22 11   6.6   3.6
  9750  -8.6  16.5  240  25 13   6.6   3.6 |  -9.3  15.3  220  23 12   6.0   3.3
  9500  -8.2  17.2  235  25 13   6.5   3.5 |  -8.9  16.0  220  23 12   6.4   3.5
  9250  -7.7  18.1  235  25 13   6.2   3.4 |  -8.4  16.9  215  23 12   7.0   3.8
  9000  -7.2  19.0  230  24 13   6.1   3.4 |  -7.9  17.8  215  23 12   7.0   3.8
  8750  -6.8  19.8  225  24 12   5.6   3.1 |  -7.4  18.7  210  23 12   6.5   3.6
  8500  -6.4  20.5  220  24 12   6.0   3.3 |  -6.9  19.6  210  23 12   6.8   3.7
  8250  -5.9  21.4  220  23 12   6.6   3.6 |  -6.4  20.5  205  21 11   7.3   4.0
  8000  -5.4  22.3  215  22 11   6.5   3.6 |  -5.9  21.4  205  20 10   7.3   4.0
  7750  -5.0  23.0  210  21 11   5.0   2.7 |  -5.4  22.3  205  19 10   6.3   3.5
  7500  -4.7  23.5  205  20 10   5.1   2.8 |  -4.9  23.2  200  18  9   6.1   3.3
  7250  -4.2  24.4  200  19 10   6.4   3.5 |  -4.4  24.1  200  17  9   6.8   3.7
  7000  -3.8  25.2  195  18  9   6.1   3.4 |  -4.0  24.8  195  16  8   6.6   3.6
  6750  -3.3  26.1  190  17  9   6.6   3.6 |  -3.5  25.7  195  15  8   7.0   3.9
  6500  -2.8  27.0  185  15  8   6.7   3.7 |  -2.9  26.8  195  13  7   7.3   4.0
  6250  -2.3  27.9  180  14  7   7.0   3.8 |  -2.4  27.7  190  12  6   7.4   4.1
  6000  -1.8  28.8  175  12  6   5.5   3.0 |  -1.9  28.6  190  10  5   6.8   3.7
  5750  -1.5  29.3  170  11  6   4.0   2.2 |  -1.4  29.5  190   9  5   8.4   4.6
  5500  -1.1  30.0  165   9  5   6.0   3.3 |  -0.6  30.9  190   8  4  13.1   7.2
  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

           12/25/2014 at 1400 MST          |       12/25/2014 at 1700 MST
                                           |
K index... +17.3  LI... +1.3               | K index... +16.7  LI... +1.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -54.3 -65.7  245  20 10   3.1   1.7 | -54.1 -65.4  245  15  8   2.7   1.5
 45000 -49.7 -57.5  250  35 18   3.1   1.7 | -50.0 -58.0  260  27 14   2.7   1.5
 40000 -48.1 -54.6  225  36 19   0.7   0.4 | -47.3 -53.1  220  36 18   1.7   0.9
 38000 -47.6 -53.7  215  38 20   1.6   0.9 | -46.3 -51.3  210  43 22   1.7   0.9
 36000 -46.7 -52.1  220  46 24   1.5   0.8 | -45.2 -49.4  215  43 22   1.6   0.9
 34000 -45.8 -50.4  225  53 27   1.5   0.8 | -44.2 -47.6  220  43 22   1.7   0.9
 32000 -45.7 -50.3  225  58 30  -0.6  -0.3 | -44.3 -47.7  220  47 24  -1.4  -0.8
 30000 -46.0 -50.8  225  60 31  -0.6  -0.3 | -45.2 -49.4  220  53 27  -1.4  -0.8
 29000 -45.8 -50.4  225  62 32   4.5   2.5 | -45.4 -49.7  220  56 29   2.5   1.4
 28000 -44.6 -48.3  225  65 33   4.0   2.2 | -44.6 -48.3  220  58 30   2.4   1.3
 27000 -43.4 -46.1  230  67 35   4.0   2.2 | -43.9 -47.0  220  60 31   2.4   1.3
 26000 -42.2 -44.0  230  70 36   4.2   2.3 | -43.2 -45.8  225  62 32   2.3   1.2
 25000 -40.5 -40.9  230  68 35   5.9   3.2 | -41.9 -43.4  220  58 30   4.7   2.6
 24000 -38.8 -37.8  230  65 33   5.9   3.2 | -40.5 -40.9  220  51 26   4.7   2.6
 23000 -37.0 -34.6  230  61 31   5.9   3.2 | -39.1 -38.4  220  45 23   4.6   2.5
 22000 -35.0 -31.0  230  50 26   5.2   2.8 | -37.5 -35.5  220  39 20   5.4   3.0
 21000 -33.5 -28.3  225  40 21   5.2   2.9 | -35.5 -31.9  210  33 17   5.4   3.0
 20000 -31.7 -25.1  215  34 17   8.0   4.4 | -33.7 -28.7  210  29 15   8.5   4.7
 19500 -30.5 -22.9  220  33 17   7.8   4.3 | -32.5 -26.5  210  28 14   8.2   4.5
 19000 -29.4 -20.9  220  33 17   7.8   4.3 | -31.2 -24.2  210  27 14   8.2   4.5
 18500 -28.2 -18.8  220  32 17   7.8   4.3 | -30.0 -22.0  210  26 13   8.2   4.5
 18000 -27.0 -16.6  220  32 16   7.8   4.3 | -28.8 -19.8  210  25 13   8.2   4.5
 17500 -25.9 -14.6  220  31 16   7.3   4.0 | -27.7 -17.9  215  23 12   7.2   3.9
 17000 -24.8 -12.6  220  31 16   7.3   4.0 | -26.6 -15.9  215  21 11   7.2   4.0
 16500 -23.7 -10.7  220  30 15   8.0   4.4 | -25.5 -13.9  220  19 10   8.1   4.5
 16000 -22.5  -8.5  220  29 15   8.1   4.4 | -24.2 -11.6  220  18  9   8.3   4.5
 15500 -21.3  -6.3  220  28 14   7.8   4.3 | -23.0  -9.4  220  16  8   8.2   4.5
 15000 -20.2  -4.4  220  27 14   7.7   4.2 | -21.8  -7.2  220  16  8   8.2   4.5
 14500 -19.1  -2.4  220  27 14   7.5   4.1 | -20.6  -5.1  220  15  8   8.1   4.4
 14000 -18.0  -0.4  220  25 13   7.0   3.8 | -19.4  -2.9  220  15  8   7.7   4.2
 13500 -17.0   1.4  220  23 12   7.0   3.9 | -18.3  -0.9  220  15  8   7.7   4.2
 13000 -15.9   3.4  215  21 11   7.1   3.9 | -17.2   1.0  220  14  7   7.6   4.2
 12500 -14.9   5.2  215  18  9   7.1   3.9 | -16.0   3.2  220  14  7   7.6   4.1
 12000 -13.8   7.2  220  17  9   7.2   3.9 | -15.0   5.0  225  14  7   7.0   3.8
 11500 -12.8   9.0  225  18  9   7.1   3.9 | -13.9   7.0  230  14  7   7.0   3.9
 11000 -11.7  10.9  225  18  9   6.8   3.7 | -12.9   8.8  235  14  7   7.1   3.9
 10500 -10.7  12.7  225  18  9   6.8   3.7 | -11.8  10.8  235  14  7   7.2   3.9
 10250 -10.2  13.6  225  18  9   7.1   3.9 | -11.3  11.7  235  14  7   7.4   4.1
 10000  -9.7  14.5  225  18  9   6.8   3.8 | -10.8  12.6  240  14  7   7.2   4.0
  9750  -9.2  15.4  225  17  9   6.3   3.4 | -10.3  13.5  240  14  7   6.5   3.6
  9500  -8.8  16.2  225  17  9   6.5   3.6 |  -9.8  14.4  240  13  7   7.0   3.8
  9250  -8.3  17.1  225  16  8   7.0   3.8 |  -9.2  15.4  240  13  7   7.7   4.3
  9000  -7.8  18.0  225  16  8   6.8   3.7 |  -8.7  16.3  240  13  7   7.5   4.1
  8750  -7.3  18.9  225  15  8   5.2   2.9 |  -8.2  17.2  245  12  6   5.9   3.2
  8500  -6.9  19.6  225  14  7   5.8   3.2 |  -7.8  18.0  245  12  6   6.1   3.4
  8250  -6.4  20.5  230  13  7   7.2   4.0 |  -7.2  19.0  250  12  6   7.3   4.0
  8000  -5.9  21.4  230  12  6   7.0   3.9 |  -6.7  19.9  250  11  6   7.3   4.0
  7750  -5.5  22.1  235  11  6   4.9   2.7 |  -6.2  20.8  255  11  6   5.1   2.8
  7500  -5.2  22.6  235  10  5   4.7   2.6 |  -5.9  21.4  255  10  5   4.7   2.6
  7250  -4.7  23.5  240   9  5   6.3   3.5 |  -5.5  22.1  265  10  5   6.3   3.5
  7000  -4.3  24.3  245   8  4   6.2   3.4 |  -5.1  22.8  270   9  5   6.2   3.4
  6750  -3.8  25.2  250   7  4   7.4   4.0 |  -4.6  23.7  280   9  5   6.7   3.7
  6500  -3.2  26.2  255   6  3   7.9   4.3 |  -4.1  24.6  285   8  4   6.6   3.6
  6250  -2.7  27.1  265   6  3   7.5   4.1 |  -3.6  25.5  290   8  4   6.5   3.5
  6000  -2.1  28.2  270   6  3   8.3   4.5 |  -3.2  26.2  300   7  4   6.9   3.8
  5750  -1.4  29.5  270   5  3  11.4   6.2 |  -2.6  27.3  305   6  3   8.9   4.9
  5500  -0.5  31.1  270   5  3  14.3   7.9 |  -1.9  28.6  300   6  3  11.1   6.1
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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