Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Thursday, March 26, 2015

This forecast is for Thursday, March 26, 2015:

If the trigger temperature of 50.9 F/10.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 553 ft/min (2.8 m/s)
   Maximum height of thermals.................. 12590 ft MSL (7751 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1245 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10790 ft MSL (5951 ft AGL)
Thermal soaring outlook for Friday 03/27....... Good

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

Remarks...

Sunrise/Sunset.................... 07:08:22 / 19:30:51 MDT
Total possible sunshine........... 12 hr 22 min 29 sec (742 min 29 sec)
Altitude of sun at 13:19:46 MDT... 53.20 degrees

Upper air data from rawinsonde observation taken on 03/26/2015 at 0600 MDT

Freezing level.................. 8263 ft MSL (3424 ft AGL)
Convective condensation level... 19436 ft MSL (14597 ft AGL)
Lifted condensation level....... 15938 ft MSL (11099 ft AGL)
Lifted index.................... +7.0
K index......................... -5.5

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  -57.2 -71.0   350   45   23  -2.0  -1.1  107.6 225.7    51.9      M    M
 45000  -58.9 -74.0   005   72   37   4.2   2.3   79.6 175.3    38.6      M    M
 40000  -54.7 -66.5   355   67   34  -7.8  -4.3   62.0 143.6    29.9      M    M
 38000  -57.4 -71.3   355   70   36  -0.3  -0.1   49.0 120.3    22.1      M    M
 36000  -59.1 -74.4   360   81   42   6.8   3.7   37.9 100.2    15.0      M    M
 34000  -54.9 -66.8   355   59   30   8.2   4.5   35.5  95.9    13.7      M    M
 32000  -50.0 -58.0   010   67   35   8.2   4.5   34.2  93.6    13.1      M    M
 30000  -45.3 -49.5   020   77   40   7.0   3.9   31.7  89.1    11.7      M    M
 29000  -43.2 -45.8   015   72   37   8.3   4.5   30.6  87.2    11.0      M    M
 28000  -40.5 -40.9   015   67   34   9.2   5.0   30.3  86.5    10.8      M    M
 27000  -37.7 -35.9   010   62   32   9.2   5.0   30.0  86.0    10.8      M    M
 26000  -35.0 -31.0   005   57   29   9.2   5.0   29.9  85.8    10.8      M    M
 25000  -32.2 -26.0   360   53   27   9.2   5.0   29.9  85.7    10.9      M    M
 24000  -29.5 -21.1   350   56   29   8.0   4.4   29.5  85.2    10.8      M    M
 23000  -27.3 -17.1   350   61   31   7.2   3.9   28.6  83.5    10.2      M    M
 22000  -25.2 -13.4   350   55   28   7.3   4.0   27.6  81.8     9.5      M    M
 21000  -22.8  -9.0   350   49   25   8.8   4.9   27.0  80.6     9.1      M    M
 20000  -20.1  -4.2   350   42   22   9.0   4.9   26.7  80.1     8.9      M    M
 19500  -18.9  -2.0   350   42   22   7.7   4.2   26.5  79.7     8.8      M    M
 19000  -17.7   0.1   350   42   22   7.7   4.2   26.1  79.0     8.5      M    M
 18500  -16.6   2.1   350   42   21   7.3   4.0   25.7  78.3     8.2      M    M
 18000  -15.5   4.1   350   41   21   8.2   4.5   25.4  77.7     7.9      M    M
 17500  -14.2   6.4   350   40   21   8.6   4.7   25.1  77.2     7.7      M    M
 17000  -12.9   8.8   350   40   20   8.6   4.7   24.9  76.9     7.6      M    M
 16500  -11.6  11.1   350   39   20   8.6   4.7   24.7  76.5     7.5      M    M
 16000   -9.7  14.5   350   38   20   5.8   3.2   24.5  76.1     7.3      M    M
 15500   -9.3  15.3   345   39   20   3.2   1.7   23.3  74.0     6.3      M    M
 15000   -8.9  16.0   345   39   20   3.3   1.8   22.2  72.0     5.3      M    M
 14500   -8.9  16.0   350   36   19  -2.2  -1.2   20.6  69.2     3.9      M    M
 14000   -9.2  15.4   355   34   17  -1.1  -0.6   18.8  65.8     2.1      M    M
 13500   -8.8  16.2   355   31   16   5.9   3.2   17.6  63.7     1.1      M    M
 13000   -8.0  17.6   350   29   15   5.6   3.1   16.9  62.4     0.5      M    M
 12500   -7.1  19.2   350   27   14   7.9   4.4   16.2  61.2    -0.2    542  2.8
 12000   -7.5  18.5   345   25   13  -5.8  -3.2   14.2  57.6    -2.0    538  2.7
 11500   -6.6  20.1   345   23   12   8.3   4.6   13.7  56.6    -2.5    495  2.5
 11000   -5.3  22.5   345   22   11   7.3   4.0   13.5  56.3    -2.7    441  2.2
 10500   -5.1  22.8   340   15    8   0.0   0.0   12.2  53.9    -3.9    420  2.1
 10250   -4.8  23.4   335   11    6   5.2   2.9   11.6  53.0    -4.5    406  2.1
 10000   -4.4  24.1   345    6    3   5.7   3.1   11.3  52.4    -4.8    387  2.0
  9750   -4.0  24.8   350    6    3   7.6   4.2   11.0  51.9    -5.1    365  1.9
  9500   -3.3  26.1   360    6    3   9.1   5.0   11.0  51.7    -5.2    338  1.7
  9250   -2.7  27.1   005    7    3   8.7   4.8   10.9  51.6    -5.2    311  1.6
  9000   -2.0  28.4   010    7    4   8.8   4.8   10.8  51.5    -5.3    284  1.4
  8750   -1.3  29.7   010    6    3   8.8   4.8   10.7  51.3    -5.4    257  1.3
  8500   -0.7  30.7   010    5    3   8.7   4.8   10.7  51.2    -5.5    230  1.2
  8250   -0.0  32.0   005    4    2   9.1   5.0   10.6  51.1    -5.6    203  1.0
  8000    0.6  33.1   005    3    2   7.6   4.2   10.5  51.0    -5.7    176  0.9
  7750    1.1  34.0   055    2    1   5.1   2.8   10.2  50.4    -6.0    155  0.8
  7500    1.4  34.5   100    4    2   5.0   2.7    9.9  49.8    -6.4    137  0.7
  7250    1.8  35.2   120    6    3   5.0   2.7    9.5  49.1    -6.7    118  0.6
  7000    2.2  36.0   125    8    4   5.0   2.7    9.2  48.5    -7.1    100  0.5
  6750    2.5  36.5   125    9    5   5.0   2.7    8.8  47.8    -7.5     82  0.4
  6500    2.9  37.2   125    9    4   5.0   2.8    8.4  47.1    -7.9     63  0.3
  6250    3.3  37.9   120    8    4   4.9   2.7    8.1  46.5    -8.3     45  0.2
  6000    3.7  38.7   120    8    4   5.3   2.9    7.7  45.9    -8.6     26  0.1
  5750    4.0  39.2   115    9    5   3.9   2.1    7.3  45.2    -9.0      8  0.0
  5500    4.2  39.6   115   11    5   1.6   0.9    6.8  44.2    -9.6      M    M
  5250    4.2  39.6   110   12    6  -2.0  -1.1    6.1  42.9   -10.4      M    M
  5000    3.6  38.5   105   11    6 -17.2  -9.4    4.7  40.5   -11.7      M    M

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

           03/26/2015 at 0900 MDT          |       03/26/2015 at 1200 MDT
                                           |
K index... -2.3  LI... +8.3                | K index... -4.5  LI... +8.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.0
                                           |
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 -58.7 -73.7  015  41 21   1.8   1.0 | -57.7 -71.9  015  47 24   1.4   0.8
 45000 -56.1 -69.0  010  67 35   0.0   0.0 | -55.7 -68.3  005  63 32  -0.1  -0.0
 40000 -55.8 -68.4  355  67 35   0.2   0.1 | -55.6 -68.1  355  70 36   0.1   0.0
 38000 -56.0 -68.8  360  67 35  -0.7  -0.4 | -56.0 -68.8  355  70 36  -1.3  -0.7
 36000 -56.4 -69.5  360  68 35  -0.7  -0.4 | -56.8 -70.2  360  66 34  -1.3  -0.7
 34000 -55.7 -68.3  005  68 35   7.7   4.2 | -55.7 -68.3  005  62 32   8.3   4.6
 32000 -50.6 -59.1  015  69 35   7.6   4.2 | -50.7 -59.3  010  57 29   8.4   4.6
 30000 -45.7 -50.3  020  68 35   9.1   5.0 | -45.6 -50.1  010  54 28   8.7   4.8
 29000 -43.0 -45.4  015  66 34   9.1   5.0 | -43.0 -45.4  010  55 29   8.7   4.8
 28000 -40.3 -40.5  015  63 33   9.1   5.0 | -40.3 -40.5  010  57 29   8.7   4.8
 27000 -37.7 -35.9  010  62 32   7.9   4.3 | -37.7 -35.9  010  57 29   9.0   5.0
 26000 -35.3 -31.5  010  61 31   8.0   4.4 | -35.0 -31.0  005  56 29   9.0   4.9
 25000 -32.8 -27.0  010  60 31   8.0   4.4 | -32.3 -26.1  005  54 28   9.0   4.9
 24000 -30.4 -22.7  010  59 31   8.3   4.6 | -29.6 -21.3  360  53 27   9.3   5.1
 23000 -27.9 -18.2  010  57 29   8.4   4.6 | -26.8 -16.2  360  51 26   9.3   5.1
 22000 -25.4 -13.7  010  54 28   8.4   4.6 | -24.0 -11.2  355  49 25   9.3   5.1
 21000 -22.8  -9.0  005  51 26   9.6   5.3 | -21.3  -6.3  355  47 24   8.5   4.6
 20000 -20.0  -4.0  005  48 25   9.6   5.2 | -18.1  -0.6  355  44 23   8.5   4.7
 19500 -18.5  -1.3  005  47 24   9.6   5.3 | -16.8   1.8  355  43 22   8.5   4.7
 19000 -17.1   1.2  360  46 23   9.8   5.4 | -15.5   4.1  355  42 21   8.2   4.5
 18500 -15.8   3.6  360  44 23   7.5   4.1 | -14.4   6.1  355  41 21   7.9   4.4
 18000 -14.1   6.6  355  41 21   7.6   4.1 | -13.2   8.2  360  40 21   7.9   4.3
 17500 -13.0   8.6  350  39 20   8.1   4.5 | -12.0  10.4  360  38 20   8.2   4.5
 17000 -11.8  10.8  350  38 19   8.1   4.4 | -10.7  12.7  355  35 18   8.2   4.5
 16500 -10.6  12.9  345  37 19   8.2   4.5 |  -9.5  14.9  355  32 17   7.8   4.3
 16000  -9.3  15.3  345  36 19   8.3   4.5 |  -8.4  16.9  350  30 16   7.6   4.2
 15500  -8.1  17.4  345  36 18   7.7   4.2 |  -7.3  18.9  345  29 15   7.5   4.1
 15000  -7.1  19.2  345  36 18   6.0   3.3 |  -6.2  20.8  345  29 15   7.2   4.0
 14500  -6.3  20.7  350  36 18   6.1   3.4 |  -5.2  22.6  350  31 16   7.2   3.9
 14000  -5.7  21.7  350  35 18   1.8   1.0 |  -4.4  24.1  350  31 16   3.4   1.9
 13500  -5.4  22.3  350  34 17   2.4   1.3 |  -3.9  25.0  350  31 16   4.2   2.3
 13000  -5.3  22.5  350  32 17   0.3   0.1 |  -3.7  25.3  350  30 15  -0.9  -0.5
 12500  -5.3  22.5  350  30 15   0.5   0.3 |  -3.8  25.2  355  28 15  -0.3  -0.2
 12000  -5.3  22.5  350  27 14  -1.0  -0.6 |  -4.0  24.8  355  26 14  -1.6  -0.9
 11500  -5.5  22.1  355  23 12  -1.3  -0.7 |  -4.2  24.4  355  24 12  -1.8  -1.0
 11000  -5.5  22.1  355  19 10   1.9   1.0 |  -4.3  24.3  360  21 11   1.1   0.6
 10500  -5.2  22.6  355  13  7   1.6   0.9 |  -4.2  24.4  360  17  9   1.0   0.5
 10250  -5.1  22.8  360  11  6   2.7   1.5 |  -4.1  24.6  360  15  8   1.4   0.7
 10000  -4.8  23.4  005  10  5   4.9   2.7 |  -3.9  25.0  005  13  7   3.4   1.9
  9750  -4.4  24.1  010   8  4   6.0   3.3 |  -3.6  25.5  010  11  6   5.4   3.0
  9500  -3.9  25.0  020   7  4   6.4   3.5 |  -3.2  26.2  015   8  4   5.8   3.2
  9250  -3.5  25.7  035   7  3   6.3   3.5 |  -2.8  27.0  025   6  3   5.5   3.0
  9000  -3.0  26.6  040   7  4   6.4   3.5 |  -2.4  27.7  040   5  2   5.7   3.1
  8750  -2.5  27.5  045   8  4   7.1   3.9 |  -1.9  28.6  055   4  2   6.9   3.8
  8500  -2.0  28.4  055   9  4   7.5   4.1 |  -1.4  29.5  075   3  2   7.7   4.2
  8250  -1.4  29.5  055   9  5   7.2   4.0 |  -0.8  30.6  085   3  2   7.6   4.2
  8000  -0.9  30.4  060  10  5   7.0   3.9 |  -0.2  31.6  090   3  2   7.4   4.1
  7750  -0.4  31.3  065  11  6   8.0   4.4 |   0.3  32.5  100   3  1   8.8   4.8
  7500   0.2  32.4  070  11  6   8.2   4.5 |   1.0  33.8  105   3  1   9.8   5.4
  7250   0.8  33.4  075  11  5   7.2   4.0 |   1.7  35.1  105   3  1   9.4   5.1
  7000   1.3  34.3  080  10  5   7.7   4.2 |   2.4  36.3  110   2  1   9.3   5.1
  6750   1.9  35.4  085  10  5   6.9   3.8 |   3.1  37.6  115   2  1  10.1   5.5
  6500   2.4  36.3  090   9  4   5.3   2.9 |   3.9  39.0  115   2  1  10.7   5.9
  6250   2.8  37.0  100   7  4   5.3   2.9 |   4.7  40.5  120   2  1  10.5   5.7
  6000   3.2  37.8  110   6  3   4.0   2.2 |   5.5  41.9  125   2  1  10.2   5.6
  5750   3.5  38.3  115   5  3   5.1   2.8 |   6.4  43.5  125   2  1  15.9   8.7
  5500   4.1  39.4  120   5  2  11.3   6.2 |   8.0  46.4  125   2  1  26.4  14.5
  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

           03/26/2015 at 1500 MDT          |       03/26/2015 at 1800 MDT
                                           |
K index... -1.5  LI... +5.7                | K index... +7.3  LI... +5.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
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 -58.3 -72.9  010  37 19   2.6   1.4 | -58.7 -73.7  360  36 19   3.6   2.0
 45000 -54.6 -66.3  010  52 27  -0.9  -0.5 | -53.7 -64.7  005  54 28  -2.3  -1.2
 40000 -55.4 -67.7  355  65 33  -0.5  -0.3 | -56.3 -69.3  350  65 33  -1.8  -1.0
 38000 -56.1 -69.0  355  67 34  -1.4  -0.8 | -56.7 -70.1  350  63 32   0.1   0.1
 36000 -57.0 -70.6  355  65 34  -1.4  -0.8 | -56.6 -69.9  355  57 29   0.1   0.1
 34000 -55.6 -68.1  355  61 31   8.9   4.9 | -54.7 -66.5  360  51 26   8.6   4.7
 32000 -50.3 -58.5  350  52 27   8.8   4.8 | -49.6 -57.3  360  46 24   8.6   4.7
 30000 -44.9 -48.8  350  45 23   9.6   5.3 | -44.3 -47.7  355  44 23   9.0   4.9
 29000 -42.0 -43.6  355  43 22   9.6   5.3 | -41.6 -42.9  355  46 24   9.0   4.9
 28000 -39.1 -38.4  355  41 21   9.6   5.3 | -38.9 -38.0  350  48 25   9.0   4.9
 27000 -36.3 -33.3  360  40 21   8.4   4.6 | -36.2 -33.2  350  49 25   8.6   4.7
 26000 -33.8 -28.8  360  43 22   8.5   4.7 | -33.7 -28.7  350  48 25   8.6   4.7
 25000 -31.2 -24.2  360  46 24   8.5   4.7 | -31.1 -24.0  355  46 24   8.6   4.7
 24000 -28.6 -19.5  360  48 25   8.5   4.7 | -28.5 -19.3  360  45 23   9.0   5.0
 23000 -26.1 -15.0  360  48 25   8.5   4.7 | -25.8 -14.4  355  45 23   9.0   4.9
 22000 -23.6 -10.5  360  48 25   8.5   4.7 | -23.1  -9.6  355  45 23   9.0   4.9
 21000 -20.6  -5.1  360  47 24   7.6   4.1 | -19.9  -3.8  350  43 22   8.1   4.4
 20000 -18.3  -0.9  360  44 22   7.6   4.2 | -17.5   0.5  350  39 20   8.1   4.4
 19500 -17.2   1.0  360  42 22   7.6   4.2 | -16.3   2.7  350  37 19   8.1   4.4
 19000 -16.1   3.0  360  41 21   8.9   4.9 | -15.1   4.8  350  35 18   8.0   4.4
 18500 -14.6   5.7  360  40 21   9.8   5.4 | -13.9   7.0  345  31 16   7.8   4.3
 18000 -13.1   8.4  355  39 20  10.0   5.5 | -12.7   9.1  340  27 14   7.8   4.3
 17500 -11.8  10.8  355  37 19   8.1   4.4 | -11.5  11.3  340  27 14   8.5   4.7
 17000 -10.5  13.1  350  34 17   8.3   4.5 | -10.3  13.5  350  29 15   8.5   4.6
 16500  -9.3  15.3  345  31 16   7.8   4.3 |  -9.1  15.6  355  32 16   7.2   3.9
 16000  -8.1  17.4  345  29 15   7.7   4.2 |  -8.1  17.4  355  33 17   6.6   3.6
 15500  -7.0  19.4  340  26 14   7.5   4.1 |  -7.1  19.2  355  34 17   6.2   3.4
 15000  -5.9  21.4  345  28 14   7.3   4.0 |  -6.3  20.7  355  33 17   5.2   2.8
 14500  -4.8  23.4  345  30 15   7.0   3.9 |  -5.6  21.9  355  31 16   5.2   2.8
 14000  -4.1  24.6  350  30 15   4.2   2.3 |  -4.8  23.4  350  30 16   4.7   2.6
 13500  -3.4  25.9  355  29 15   4.5   2.5 |  -4.1  24.6  350  30 15   4.8   2.6
 13000  -2.9  26.8  355  28 14   2.9   1.6 |  -3.5  25.7  350  29 15   4.0   2.2
 12500  -2.5  27.5  355  27 14   3.5   1.9 |  -2.9  26.8  350  27 14   4.3   2.3
 12000  -2.3  27.9  355  25 13  -1.1  -0.6 |  -2.4  27.7  350  24 12   2.9   1.6
 11500  -2.5  27.5  355  22 11  -0.6  -0.3 |  -2.0  28.4  345  20 10   2.8   1.5
 11000  -2.7  27.1  355  17  9  -1.0  -0.6 |  -1.5  29.3  340  16  8   4.5   2.5
 10500  -2.9  26.8  355  11  5  -1.1  -0.6 |  -0.9  30.4  335  12  6   4.2   2.3
 10250  -2.9  26.8  360   8  4   1.1   0.6 |  -0.6  30.9  330  11  5   5.5   3.0
 10000  -2.7  27.1  360   7  4   5.1   2.8 |  -0.1  31.8  325  10  5   7.1   3.9
  9750  -2.2  28.0  360   5  3   6.7   3.7 |   0.5  32.9  325   8  4   7.0   3.8
  9500  -1.7  28.9  355   3  2   6.9   3.8 |   1.0  33.8  315   6  3   7.0   3.8
  9250  -1.2  29.8  345   2  1   7.2   4.0 |   1.5  34.7  305   5  2   6.3   3.4
  9000  -0.6  30.9  320   1  1   7.7   4.2 |   1.9  35.4  295   4  2   6.3   3.4
  8750  -0.0  32.0  290   1  1   9.0   4.9 |   2.5  36.5  280   3  2   7.5   4.1
  8500   0.7  33.3  275   2  1   9.0   4.9 |   3.0  37.4  255   3  2   7.4   4.1
  8250   1.3  34.3  270   2  1   8.1   4.5 |   3.5  38.3  240   3  2   6.7   3.7
  8000   1.9  35.4  270   2  1   8.1   4.4 |   4.0  39.2  230   3  2   6.6   3.6
  7750   2.5  36.5  265   2  1   9.0   4.9 |   4.6  40.3  220   4  2   7.4   4.1
  7500   3.3  37.9  265   1  1  10.1   5.5 |   5.2  41.4  220   4  2   7.6   4.1
  7250   4.0  39.2  265   2  1  10.2   5.6 |   5.7  42.3  220   4  2   7.1   3.9
  7000   4.8  40.6  265   2  1  10.1   5.5 |   6.2  43.2  220   4  2   7.0   3.9
  6750   5.5  41.9  265   2  1  10.5   5.8 |   6.7  44.1  220   4  2   7.8   4.3
  6500   6.3  43.3  260   2  1  10.4   5.7 |   7.4  45.3  220   4  2   9.6   5.3
  6250   7.1  44.8  255   2  1  10.3   5.7 |   8.1  46.6  220   3  2   9.8   5.4
  6000   7.8  46.0  255   2  1   9.3   5.1 |   8.9  48.0  220   3  2  10.4   5.7
  5750   8.7  47.7  250   2  1  15.6   8.5 |   9.7  49.5  220   4  2  13.5   7.4
  5500  10.3  50.5  260   2  1  29.3  16.0 |  10.9  51.6  225   3  2  16.6   9.1
  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 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.

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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