Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 041335
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0635 MST Wednesday, March 4, 2015

This forecast is for Wednesday, March 4, 2015:

If the trigger temperature of 33.0 F/0.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 474 ft/min (2.4 m/s)
   Maximum height of thermals.................. 11377 ft MSL (6544 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... 1015 MST
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................. 8984 ft MSL (4151 ft AGL)
Thermal soaring outlook for Thursday 03/05..... Poor

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

Remarks...

Sunrise/Sunset.................... 06:42:27 / 18:08:35 MST
Total possible sunshine........... 11 hr 26 min 8 sec (686 min 8 sec)
Altitude of sun at 12:25:44 MST... 44.57 degrees

Upper air data from rawinsonde observation taken on 03/04/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9673 ft MSL (4840 ft AGL)
Lifted condensation level....... 10626 ft MSL (5793 ft AGL)
Lifted index.................... +7.7
K index......................... +0.8

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  -56.3 -69.3   265   55   28  -2.7  -1.5  110.4 230.8    60.2      M    M
 45000  -53.7 -64.7   245   60   31  10.0   5.5   89.9 193.8    52.0      M    M
 40000  -50.1 -58.2   245   58   30   6.6   3.6   72.1 161.9    44.1      M    M
 38000  -49.1 -56.4   265   54   28 -11.9  -6.5   64.8 148.6    40.4      M    M
 36000  -50.3 -58.5   260   58   30  -0.1  -0.1   53.2 127.8    33.7      M    M
 34000  -48.4 -55.1   255   62   32  -4.5  -2.5   47.5 117.5    30.6      M    M
 32000  -47.1 -52.8   260   48   25  -0.0  -0.0   41.1 106.0    26.8      M    M
 30000  -45.7 -50.3   260   55   28  -2.6  -1.4   34.9  94.8    22.9      M    M
 29000  -45.3 -49.5   265   46   24   4.7   2.6   31.4  88.6    20.6      M    M
 28000  -44.3 -47.7   280   34   17  -2.8  -1.5   29.0  84.2    19.0      M    M
 27000  -43.3 -45.9   305   34   17   4.0   2.2   26.4  79.5    17.3      M    M
 26000  -43.0 -45.4   330   40   20   6.3   3.4   23.0  73.5    14.9      M    M
 25000  -40.8 -41.4   340   49   25   7.4   4.1   22.1  71.7    14.3      M    M
 24000  -39.1 -38.4   335   49   25   5.0   2.8   20.5  68.9    13.2      M    M
 23000  -37.6 -35.7   340   41   21   5.3   2.9   18.7  65.7    12.0      M    M
 22000  -36.0 -32.8   330   34   18   5.4   3.0   17.1  62.7    10.8      M    M
 21000  -34.1 -29.4   315   29   15   7.9   4.4   15.8  60.5     9.9      M    M
 20000  -31.8 -25.2   325   32   16   7.7   4.2   15.2  59.3     9.4      M    M
 19500  -30.6 -23.1   325   33   17   7.7   4.2   14.8  58.6     9.2      M    M
 19000  -28.9 -20.0   330   35   18   7.7   4.2   14.2  57.6     8.8      M    M
 18500  -27.7 -17.9   330   37   19   7.7   4.2   13.9  57.0     8.5      M    M
 18000  -26.6 -15.9   325   36   18   6.7   3.7   13.6  56.4     8.3      M    M
 17500  -26.0 -14.8   325   33   17   3.1   1.7   12.6  54.6     7.5      M    M
 17000  -25.6 -14.1   320   29   15   1.1   0.6   11.3  52.3     6.4      M    M
 16500  -25.5 -13.9   320   26   14   3.6   1.9    9.8  49.6     5.1      M    M
 16000  -24.5 -12.1   315   24   12   6.9   3.8    9.2  48.6     4.7      M    M
 15500  -23.5 -10.3   305   23   12   7.0   3.8    8.7  47.7     4.3      M    M
 15000  -22.5  -8.5   300   22   11   7.0   3.9    8.3  46.9     3.9      M    M
 14500  -21.4  -6.5   305   22   11   8.0   4.4    7.8  46.0     3.4      M    M
 14000  -20.9  -5.6   310   22   11   0.4   0.2    6.7  44.1     2.5      M    M
 13500  -20.2  -4.4   305   19   10   2.7   1.5    5.9  42.6     1.8      M    M
 13000  -19.5  -3.1   305   16    8   9.7   5.3    5.2  41.4     1.0      M    M
 12500  -18.3  -0.9   300   13    7   7.9   4.3    4.9  40.8     0.7      M    M
 12000  -17.2   1.0   290   11    6   7.7   4.2    4.6  40.2     0.4      M    M
 11500  -16.0   3.2   295   10    5   7.7   4.2    4.2  39.6     0.1      M    M
 11000  -14.9   5.2   305    8    4   6.8   3.7    3.9  39.0    -0.2    436  2.2
 10500  -14.1   6.6   320    8    4   4.7   2.6    3.1  37.6    -1.0    398  2.0
 10250  -13.8   7.2   325    7    4   4.8   2.6    2.7  36.9    -1.3    380  1.9
 10000  -13.4   7.9   335    7    4   4.6   2.5    2.3  36.2    -1.7    362  1.8
  9750  -13.0   8.6   340    7    4   5.5   3.0    2.0  35.5    -2.1    344  1.7
  9500  -12.6   9.3   340    8    4   6.3   3.4    1.7  35.0    -2.4    323  1.6
  9250  -12.1  10.2   345    9    5   6.1   3.3    1.4  34.5    -2.7    302  1.5
  9000  -11.7  10.9   345   10    5   6.1   3.4    1.1  34.0    -3.0    281  1.4
  8750  -11.2  11.8   345    9    5   6.2   3.4    0.8  33.5    -3.3    260  1.3
  8500  -10.8  12.6   345    9    4   5.9   3.2    0.5  33.0    -3.5    239  1.2
  8250  -10.3  13.5   345    8    4   7.2   3.9    0.3  32.5    -3.8    218  1.1
  8000   -9.7  14.5   345    7    4   8.7   4.8    0.1  32.3    -3.9    192  1.0
  7750   -9.1  15.6   345    7    4   8.5   4.7    0.1  32.1    -4.1    166  0.8
  7500   -8.5  16.7   345    7    4   8.5   4.7   -0.0  31.9    -4.2    139  0.7
  7250   -7.8  18.0   340    8    4   8.5   4.7   -0.1  31.8    -4.3    113  0.6
  7000   -7.2  19.0   340    8    4   8.5   4.7   -0.2  31.6    -4.4     86  0.4
  6750   -6.5  20.3   355    8    4   8.5   4.7   -0.3  31.4    -4.5     60  0.3
  6500   -5.9  21.4   015   10    5   8.5   4.7   -0.4  31.2    -4.6     33  0.2
  6250   -5.3  22.5   025   12    6   8.5   4.7   -0.5  31.1    -4.7      7  0.0
  6000   -4.6  23.7   035   14    7   8.5   4.7   -0.6  30.9    -4.8      M    M
  5750   -4.0  24.8   035   14    7   8.4   4.6   -0.7  30.7    -4.9      M    M
  5500   -3.4  25.9   040   12    6   8.3   4.6   -0.8  30.5    -5.0      M    M
  5250   -2.8  27.0   040   11    6   8.3   4.5   -0.9  30.3    -5.2      M    M
  5000   -2.1  28.2   045    9    5   8.6   4.7   -1.0  30.2    -5.3      M    M

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

           03/04/2015 at 0800 MST          |       03/04/2015 at 1100 MST
                                           |
K index... -6.6  LI... +6.9                | K index... -9.0  LI... +6.5
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -55.9 -68.6  275  44 23   2.2   1.2 | -55.9 -68.6  280  41 21   2.7   1.5
 45000 -52.5 -62.5  270  49 25   2.2   1.2 | -51.8 -61.2  275  45 23   2.7   1.5
 40000 -49.5 -57.1  270  49 25   2.0   1.1 | -49.7 -57.5  280  45 23   1.2   0.6
 38000 -48.4 -55.1  270  49 25  -0.7  -0.4 | -49.1 -56.4  285  44 23  -0.2  -0.1
 36000 -48.7 -55.7  270  47 24  -0.5  -0.3 | -49.2 -56.6  290  42 22  -0.1  -0.1
 34000 -49.0 -56.2  275  47 24  -0.4  -0.2 | -49.3 -56.7  295  40 21  -0.1  -0.1
 32000 -48.6 -55.5  295  40 21   1.0   0.5 | -48.7 -55.7  320  41 21   1.5   0.8
 30000 -48.0 -54.4  325  38 20   1.1   0.6 | -47.8 -54.0  340  51 26   1.5   0.8
 29000 -47.4 -53.3  335  42 22   3.5   1.9 | -47.1 -52.8  345  56 29   3.6   2.0
 28000 -46.4 -51.5  335  48 25   3.4   1.9 | -46.0 -50.8  350  59 30   3.6   2.0
 27000 -45.4 -49.7  340  54 28   3.4   1.9 | -44.7 -48.5  350  63 33   3.6   1.9
 26000 -43.9 -47.0  345  60 31   6.5   3.5 | -43.5 -46.3  350  65 34   5.5   3.0
 25000 -42.1 -43.8  345  60 31   6.1   3.3 | -41.9 -43.4  350  64 33   5.3   2.9
 24000 -40.3 -40.5  345  60 31   6.1   3.3 | -40.3 -40.5  350  62 32   5.3   2.9
 23000 -38.4 -37.1  345  59 30   7.3   4.0 | -38.5 -37.3  350  60 31   7.7   4.2
 22000 -36.2 -33.2  340  56 29   7.3   4.0 | -36.3 -33.3  345  59 30   7.4   4.1
 21000 -34.0 -29.2  340  52 27   7.3   4.0 | -34.1 -29.4  345  58 30   7.4   4.1
 20000 -31.8 -25.2  340  49 25   7.8   4.3 | -31.9 -25.4  345  55 28   7.2   4.0
 19500 -30.6 -23.1  340  48 25   7.8   4.3 | -30.8 -23.4  340  53 27   7.2   4.0
 19000 -29.4 -20.9  335  46 24   7.8   4.3 | -29.8 -21.6  340  51 26   7.2   4.0
 18500 -28.3 -18.9  335  45 23   7.7   4.2 | -28.7 -19.7  340  49 25   7.2   3.9
 18000 -27.1 -16.8  335  43 22   7.2   3.9 | -27.6 -17.7  340  47 24   6.9   3.8
 17500 -26.1 -15.0  335  41 21   6.6   3.6 | -26.6 -15.9  335  44 23   6.6   3.6
 17000 -25.1 -13.2  330  38 19   6.5   3.6 | -25.6 -14.1  335  41 21   6.6   3.6
 16500 -24.2 -11.6  330  35 18   5.9   3.2 | -24.7 -12.5  335  39 20   6.3   3.5
 16000 -23.3  -9.9  330  33 17   6.0   3.3 | -23.7 -10.7  335  36 19   6.3   3.5
 15500 -22.5  -8.5  325  31 16   5.6   3.1 | -22.8  -9.0  330  34 17   6.2   3.4
 15000 -21.6  -6.9  325  29 15   5.6   3.1 | -21.9  -7.4  330  31 16   6.3   3.4
 14500 -20.8  -5.4  325  27 14   5.4   2.9 | -21.0  -5.8  330  29 15   5.1   2.8
 14000 -20.1  -4.2  325  26 13   5.2   2.9 | -20.3  -4.5  330  26 13   4.9   2.7
 13500 -19.3  -2.7  320  24 12   3.7   2.0 | -19.6  -3.3  330  23 12   4.5   2.5
 13000 -18.8  -1.8  320  20 10   2.3   1.3 | -18.6  -1.5  330  19 10   4.4   2.4
 12500 -18.2  -0.8  320  17  9   5.5   3.0 | -18.0  -0.4  330  16  8   4.9   2.7
 12000 -17.5   0.5  320  14  7   5.2   2.9 | -17.3   0.9  335  13  6   4.9   2.7
 11500 -16.7   1.9  320  11  6   5.8   3.2 | -16.5   2.3  335  10  5   5.4   2.9
 11000 -15.8   3.6  325   9  5   5.8   3.2 | -15.7   3.7  340   8  4   5.6   3.1
 10500 -14.9   5.2  335   8  4   6.6   3.6 | -14.8   5.4  340   7  4   6.7   3.7
 10250 -14.4   6.1  345   8  4   7.1   3.9 | -14.3   6.3  345   6  3   7.2   4.0
 10000 -13.9   7.0  350   7  4   4.9   2.7 | -13.8   7.2  345   6  3   5.1   2.8
  9750 -13.6   7.5  005   8  4   5.4   3.0 | -13.4   7.9  350   6  3   6.4   3.5
  9500 -13.1   8.4  015   9  4   7.9   4.3 | -12.8   9.0  360   6  3   9.6   5.3
  9250 -12.5   9.5  025  10  5   7.3   4.0 | -12.1  10.2  010   6  3   8.4   4.6
  9000 -12.0  10.4  030  11  6   6.4   3.5 | -11.5  11.3  015   5  3   6.8   3.7
  8750 -11.5  11.3  040  12  6   6.2   3.4 | -11.1  12.0  025   5  3   7.0   3.8
  8500 -11.0  12.2  045  12  6   7.1   3.9 | -10.5  13.1  040   5  2   8.5   4.7
  8250 -10.5  13.1  050  13  7   6.6   3.6 |  -9.9  14.2  050   5  2   7.3   4.0
  8000 -10.0  14.0  055  13  7   6.0   3.3 |  -9.4  15.1  055   4  2   6.3   3.5
  7750  -9.5  14.9  060  12  6   6.5   3.6 |  -8.9  16.0  050   4  2   7.2   4.0
  7500  -9.0  15.8  065  12  6   7.1   3.9 |  -8.3  17.1  045   3  2   8.0   4.4
  7250  -8.5  16.7  070  11  6   7.3   4.0 |  -7.7  18.1  040   3  2   8.3   4.6
  7000  -8.0  17.6  075  10  5   7.5   4.1 |  -7.1  19.2  040   3  1   8.6   4.7
  6750  -7.4  18.7  075   9  5   7.5   4.1 |  -6.5  20.3  035   2  1   8.9   4.9
  6500  -6.9  19.6  075   8  4   7.5   4.1 |  -5.8  21.6  030   2  1  10.3   5.7
  6250  -6.3  20.7  070   7  4   7.8   4.3 |  -4.9  23.2  030   2  1  11.3   6.2
  6000  -5.8  21.6  070   6  3   7.3   4.0 |  -4.1  24.6  030   2  1  10.4   5.7
  5750  -5.3  22.5  070   5  3   6.4   3.5 |  -3.4  25.9  025   2  1  10.2   5.6
  5500  -4.8  23.4  070   4  2   6.7   3.7 |  -2.6  27.3  020   2  1  10.9   6.0
  5250  -4.3  24.3  075   4  2   7.6   4.1 |  -1.8  28.8  015   2  1  10.8   5.9
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/04/2015 at 1400 MST          |       03/04/2015 at 1700 MST
                                           |
K index... -14.3  LI... +6.4               | K index... -19.5  LI... +8.1
CAPE... 0.0  CIN... M                      | CAPE... +7.3  CIN... -13.9
                                           |
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 -56.0 -68.8  275  41 21   2.9   1.6 | -56.4 -69.5  280  41 21   2.8   1.5
 45000 -51.6 -60.9  280  41 21   2.9   1.6 | -52.3 -62.1  280  41 21   2.7   1.5
 40000 -50.1 -58.2  290  39 20   0.7   0.4 | -51.8 -61.2  295  38 19  -0.0  -0.0
 38000 -49.8 -57.6  300  39 20  -0.4  -0.2 | -52.0 -61.6  305  36 19  -1.9  -1.1
 36000 -50.0 -58.0  310  36 19  -0.4  -0.2 | -53.2 -63.8  325  34 18  -1.9  -1.0
 34000 -50.2 -58.4  320  35 18  -0.3  -0.2 | -54.3 -65.7  350  38 19  -2.1  -1.2
 32000 -49.6 -57.3  345  45 23   1.4   0.8 | -52.4 -62.3  360  48 25   4.4   2.4
 30000 -48.8 -55.8  360  62 32   1.5   0.8 | -49.7 -57.5  005  60 31   4.1   2.3
 29000 -47.3 -53.1  005  70 36   5.4   3.0 | -47.7 -53.9  010  64 33   7.9   4.3
 28000 -45.7 -50.3  005  74 38   5.4   2.9 | -44.7 -48.5  010  66 34   7.9   4.3
 27000 -44.1 -47.4  005  79 40   5.4   3.0 | -42.4 -44.3  010  68 35   7.8   4.3
 26000 -42.3 -44.1  010  81 42   7.1   3.9 | -40.3 -40.5  010  68 35   6.0   3.3
 25000 -40.2 -40.4  010  81 42   7.0   3.9 | -38.6 -37.5  010  66 34   5.9   3.2
 24000 -38.1 -36.6  005  81 42   7.0   3.9 | -36.8 -34.2  010  65 33   5.9   3.2
 23000 -36.1 -33.0  005  79 41   5.3   2.9 | -34.9 -30.8  010  63 33   6.8   3.7
 22000 -34.5 -30.1  005  74 38   5.5   3.0 | -32.9 -27.2  010  62 32   6.8   3.7
 21000 -32.9 -27.2  360  69 36   5.5   3.0 | -30.9 -23.6  005  62 32   6.7   3.7
 20000 -31.0 -23.8  360  65 33   6.9   3.8 | -28.7 -19.7  005  62 32   7.6   4.2
 19500 -29.9 -21.8  360  63 32   6.9   3.8 | -27.5 -17.5  005  62 32   7.6   4.2
 19000 -28.9 -20.0  355  60 31   6.9   3.8 | -26.4 -15.5  005  62 32   7.6   4.2
 18500 -27.9 -18.2  355  58 30   6.9   3.8 | -25.2 -13.4  005  62 32   7.7   4.2
 18000 -26.8 -16.2  355  56 29   7.0   3.8 | -24.2 -11.6  005  62 32   6.4   3.5
 17500 -25.8 -14.4  355  54 28   7.0   3.8 | -23.2  -9.8  005  60 31   6.2   3.4
 17000 -24.7 -12.5  355  51 26   6.7   3.7 | -22.3  -8.1  005  59 31   5.7   3.1
 16500 -23.8 -10.8  355  48 25   5.7   3.1 | -21.5  -6.7  005  57 29   4.9   2.7
 16000 -23.0  -9.4  350  45 23   5.8   3.2 | -20.8  -5.4  005  55 28   4.9   2.7
 15500 -22.2  -8.0  350  42 22   4.7   2.6 | -20.1  -4.2  005  51 26   4.2   2.3
 15000 -21.5  -6.7  350  39 20   4.9   2.7 | -19.5  -3.1  005  47 24   4.5   2.5
 14500 -20.8  -5.4  345  36 18   3.6   2.0 | -19.0  -2.2  005  43 22   2.4   1.3
 14000 -20.1  -4.2  345  32 17   3.8   2.1 | -18.6  -1.5  360  38 20   2.6   1.4
 13500 -19.4  -2.9  345  30 15   5.3   2.9 | -18.3  -0.9  360  32 16   0.5   0.3
 13000 -18.6  -1.5  345  28 14   5.3   2.9 | -18.3  -0.9  360  27 14   1.6   0.9
 12500 -17.8  -0.0  345  24 12   5.8   3.2 | -17.7   0.1  355  25 13   5.0   2.7
 12000 -17.0   1.4  345  20 10   6.1   3.4 | -17.1   1.2  355  23 12   6.2   3.4
 11500 -15.9   3.4  345  17  9   7.8   4.3 | -15.8   3.6  355  20 10   9.6   5.3
 11000 -14.8   5.4  345  14  7   7.9   4.3 | -14.4   6.1  350  17  9   9.4   5.2
 10500 -13.6   7.5  340  11  6   8.0   4.4 | -13.0   8.6  350  14  7   9.4   5.1
 10250 -13.0   8.6  340  10  5   8.7   4.8 | -12.4   9.7  350  13  7   8.1   4.4
 10000 -12.4   9.7  340   9  4   5.5   3.0 | -11.9  10.6  350  12  6   5.5   3.0
  9750 -12.0  10.4  335   8  4   6.3   3.5 | -11.4  11.5  350  11  6   8.1   4.5
  9500 -11.4  11.5  335   7  4  10.2   5.6 | -10.7  12.7  345  10  5  11.2   6.1
  9250 -10.7  12.7  330   6  3   8.6   4.7 |  -9.9  14.2  345   9  4   9.1   5.0
  9000 -10.1  13.8  325   5  3   7.1   3.9 |  -9.3  15.3  345   8  4   7.0   3.9
  8750  -9.6  14.7  320   4  2   7.3   4.0 |  -8.8  16.2  340   7  3   7.9   4.4
  8500  -9.0  15.8  315   4  2   8.4   4.6 |  -8.2  17.2  340   6  3   9.2   5.0
  8250  -8.4  16.9  300   3  2   7.4   4.1 |  -7.5  18.5  335   5  2   7.7   4.2
  8000  -7.9  17.8  290   3  1   6.8   3.7 |  -7.0  19.4  330   4  2   6.7   3.7
  7750  -7.3  18.9  280   3  1   7.2   3.9 |  -6.5  20.3  320   3  2   7.0   3.8
  7500  -6.8  19.8  275   2  1   7.9   4.3 |  -6.0  21.2  310   2  1   7.4   4.1
  7250  -6.2  20.8  270   2  1   9.0   4.9 |  -5.4  22.3  295   2  1   8.1   4.4
  7000  -5.5  22.1  265   2  1   9.4   5.1 |  -4.8  23.4  285   2  1   8.1   4.4
  6750  -4.8  23.4  265   2  1   9.8   5.4 |  -4.2  24.4  275   2  1   7.8   4.3
  6500  -4.1  24.6  260   3  1  10.4   5.7 |  -3.6  25.5  260   2  1   9.3   5.1
  6250  -3.3  26.1  260   2  1  10.7   5.9 |  -2.8  27.0  255   2  1  10.8   5.9
  6000  -2.5  27.5  260   2  1   9.6   5.3 |  -2.1  28.2  250   2  1   9.8   5.4
  5750  -1.8  28.8  255   3  1  10.2   5.6 |  -1.4  29.5  245   2  1   8.0   4.4
  5500  -1.0  30.2  260   3  1  12.3   6.8 |  -0.9  30.4  255   2  1   7.0   3.9
  5250  -0.1  31.8  265   3  1  11.0   6.0 |  -0.3  31.5  260   2  1   7.8   4.3
  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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