Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241213
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0613 MDT Tuesday, March 24, 2015

This forecast is for Tuesday, March 24, 2015:

If the trigger temperature of 48.8 F/9.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 1522 ft/min (7.7 m/s)
   Maximum height of thermals.................. 21622 ft MSL (16337 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 0900 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 17615 ft MSL (12330 ft AGL)
Thermal soaring outlook for Wednesday 03/25.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14374 ft MSL (9089 ft AGL)
Wave soaring outlook for Wednesday 03/25....... Poor

Remarks...

Sunrise/Sunset.................... 06:56:44 / 19:14:21 MDT
Total possible sunshine........... 12 hr 17 min 37 sec (737 min 37 sec)
Altitude of sun at 13:05:43 MDT... 51.76 degrees

Upper air data from rawinsonde observation taken on 03/24/2015 at 0600 MDT

Freezing level.................. 8149 ft MSL (2864 ft AGL)
Convective condensation level... 13752 ft MSL (8467 ft AGL)
Lifted condensation level....... 16019 ft MSL (10734 ft AGL)
Lifted index.................... -1.9
K index......................... +5.2

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  -54.0 -65.2   250   26   13   4.9   2.7  111.4 232.5    53.3      M    M
 45000  -52.1 -61.8   250   54   28   1.5   0.8   89.7 193.4    43.8      M    M
 40000  -52.9 -63.2   260   49   25   5.7   3.1   64.0 147.1    30.2      M    M
 38000  -50.7 -59.3   275   49   25  -2.3  -1.2   58.5 137.4    27.3      M    M
 36000  -53.9 -65.0   270   51   26   7.9   4.3   45.2 113.3    18.9      M    M
 34000  -50.8 -59.4   265   36   19  -2.5  -1.4   41.4 106.4    16.7      M    M
 32000  -48.4 -55.1   275   31   16   0.6   0.3   36.6  97.8    13.6      M    M
 30000  -46.9 -52.4   265   40   21  -2.8  -1.5   30.7  87.2     9.6      M    M
 29000  -47.6 -53.7   260   33   17   1.3   0.7   25.9  78.6     6.1      M    M
 28000  -45.6 -50.1   235   24   13   6.0   3.3   23.6  74.5     4.5      M    M
 27000  -43.5 -46.3   215   29   15   8.6   4.7   22.6  72.7     3.8      M    M
 26000  -40.9 -41.6   205   34   17   8.7   4.7   22.2  71.9     3.4      M    M
 25000  -38.4 -37.1   200   37   19   8.1   4.4   21.6  71.0     3.1      M    M
 24000  -36.0 -32.8   215   30   15   8.4   4.6   21.0  69.8     2.6      M    M
 23000  -33.9 -29.0   230   26   13   6.5   3.5   20.0  67.9     1.8      M    M
 22000  -32.0 -25.6   260   21   11   6.1   3.3   18.8  65.8     0.8      M    M
 21000  -31.4 -24.5   295   23   12   6.3   3.4   16.1  60.9    -1.5   1493  7.6
 20000  -29.2 -20.6   290   27   14   7.6   4.2   15.2  59.3    -2.3   1398  7.1
 19500  -27.9 -18.2   290   27   14   9.0   4.9   14.9  58.9    -2.5   1345  6.8
 19000  -26.6 -15.9   290   28   14   9.0   4.9   14.8  58.6    -2.6   1290  6.6
 18500  -25.2 -13.4   290   28   14   8.6   4.7   14.6  58.4    -2.8   1236  6.3
 18000  -23.9 -11.0   290   28   15   9.2   5.0   14.5  58.1    -2.9   1181  6.0
 17500  -22.5  -8.5   290   29   15   9.5   5.2   14.4  57.9    -3.0   1125  5.7
 17000  -21.1  -6.0   290   30   16   9.5   5.2   14.4  57.8    -3.1   1067  5.4
 16500  -19.7  -3.5   290   31   16   9.5   5.2   14.3  57.8    -3.1   1010  5.1
 16000  -18.3  -0.9   290   32   16   9.7   5.3   14.3  57.7    -3.2    953  4.8
 15500  -17.0   1.4   290   34   17   7.1   3.9   14.1  57.4    -3.4    899  4.6
 15000  -15.9   3.4   295   36   19   7.0   3.8   13.6  56.5    -3.8    854  4.3
 14500  -14.9   5.2   295   39   20   7.0   3.8   13.2  55.7    -4.3    808  4.1
 14000  -13.4   7.9   295   41   21   7.0   3.8   12.5  54.5    -4.9    740  3.8
 13500  -12.3   9.9   310   37   19   8.5   4.7   12.1  53.8    -5.4    693  3.5
 13000  -11.7  10.9   320   34   18   9.2   5.0   12.0  53.7    -5.5    638  3.2
 12500   -9.6  14.7   315   31   16   9.2   5.1   12.0  53.5    -5.6    582  3.0
 12000   -8.2  17.2   315   28   14   9.2   5.1   11.9  53.4    -5.7    526  2.7
 11500   -6.8  19.8   315   27   14   9.2   5.1   11.8  53.2    -5.8    470  2.4
 11000   -5.5  22.1   320   26   14   9.4   5.2   11.7  53.0    -6.0    415  2.1
 10500   -4.5  23.9   320   26   13   4.0   2.2   11.2  52.1    -6.5    372  1.9
 10250   -4.2  24.4   320   25   13   4.3   2.3   10.8  51.4    -6.9    355  1.8
 10000   -3.9  25.0   315   25   13   5.4   3.0   10.3  50.6    -7.4    338  1.7
  9750   -3.4  25.9   310   24   13   6.9   3.8   10.1  50.1    -7.7    317  1.6
  9500   -2.9  26.8   310   24   12   6.6   3.6    9.8  49.7    -7.9    294  1.5
  9250   -2.5  27.5   305   23   12   6.8   3.7    9.6  49.3    -8.2    272  1.4
  9000   -2.0  28.4   300   23   12   6.6   3.6    9.4  48.9    -8.4    250  1.3
  8750   -1.5  29.3   295   24   12   7.6   4.2    9.1  48.5    -8.7    228  1.2
  8500   -0.8  30.6   295   25   13   8.6   4.7    9.0  48.3    -8.8    202  1.0
  8250   -0.2  31.6   290   26   13   8.3   4.6    8.9  48.1    -8.9    176  0.9
  8000    0.4  32.7   290   27   14   8.4   4.6    8.9  47.9    -9.0    150  0.8
  7750    1.0  33.8   285   26   14   8.4   4.6    8.7  47.7    -9.2    124  0.6
  7500    1.7  35.1   280   26   13   8.4   4.6    8.6  47.5    -9.3     98  0.5
  7250    2.3  36.1   275   26   13   8.4   4.6    8.5  47.4    -9.5     71  0.4
  7000    2.9  37.2   270   26   13   8.4   4.6    8.4  47.2    -9.6     45  0.2
  6750    3.5  38.3   270   26   13   8.4   4.6    8.3  47.0    -9.7     19  0.1
  6500    4.1  39.4   270   25   13   8.4   4.6    8.2  46.8    -9.9      M    M
  6250    4.7  40.5   265   25   13   7.7   4.2    8.1  46.6   -10.0      M    M
  6000    5.3  41.5   265   25   13   7.2   4.0    7.9  46.2   -10.3      M    M
  5750    5.8  42.4   265   19   10   7.5   4.1    7.7  45.9   -10.5      M    M
  5500    6.3  43.3   265   13    7   7.0   3.8    7.6  45.6   -10.7      M    M

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

           03/24/2015 at 0900 MDT          |       03/24/2015 at 1200 MDT
                                           |
K index... -21.2  LI... +275.9             | K index... -3.2  LI... +278.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.0
                                           |
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 -55.8 -68.4  245  30 15   0.6   0.3 | -55.6 -68.1  250  31 16   0.0   0.0
 45000 -54.8 -66.6  260  44 23   0.6   0.4 | -55.6 -68.1  265  49 25   0.0   0.0
 40000 -54.1 -65.4  270  48 25   0.5   0.3 | -56.2 -69.2  285  56 29  -0.5  -0.3
 38000 -54.0 -65.2  275  52 27  -0.8  -0.5 | -56.7 -70.1  290  61 31  -1.8  -1.0
 36000 -54.5 -66.1  280  62 32  -0.8  -0.5 | -57.8 -72.0  290  67 34  -1.8  -1.0
 34000 -55.0 -67.0  290  74 38   1.2   0.6 | -58.6 -73.5  295  73 38   6.9   3.8
 32000 -52.5 -62.5  295  67 35   4.4   2.4 | -53.1 -63.6  290  71 37   9.3   5.1
 30000 -49.8 -57.6  310  63 32   6.1   3.3 | -47.6 -53.7  290  70 36   8.5   4.7
 29000 -47.7 -53.9  310  65 33   7.1   3.9 | -45.0 -49.0  290  71 36   8.6   4.7
 28000 -45.5 -49.9  315  67 35   7.1   3.9 | -42.4 -44.3  295  71 37   8.6   4.7
 27000 -43.4 -46.1  315  70 36   7.1   3.9 | -39.9 -39.8  295  72 37   8.6   4.7
 26000 -41.1 -42.0  315  71 37   8.0   4.4 | -37.5 -35.5  300  72 37   7.9   4.3
 25000 -38.7 -37.7  315  71 37   8.0   4.4 | -35.1 -31.2  300  71 37   7.9   4.3
 24000 -36.2 -33.2  315  71 37   8.1   4.4 | -32.7 -26.9  305  71 36   7.9   4.3
 23000 -33.9 -29.0  315  70 36   7.8   4.3 | -30.5 -22.9  305  69 35   7.4   4.1
 22000 -31.5 -24.7  315  68 35   7.8   4.3 | -28.2 -18.8  305  65 34   7.4   4.1
 21000 -29.2 -20.6  315  66 34   7.8   4.3 | -26.0 -14.8  305  62 32   7.3   4.0
 20000 -26.8 -16.2  315  63 32   7.9   4.3 | -24.0 -11.2  305  57 30   6.7   3.7
 19500 -25.7 -14.3  315  61 32   7.9   4.3 | -23.0  -9.4  305  55 28   6.7   3.7
 19000 -24.5 -12.1  315  60 31   7.9   4.3 | -22.0  -7.6  305  53 27   6.8   3.7
 18500 -23.3  -9.9  315  58 30   7.9   4.3 | -21.0  -5.8  300  50 26   6.8   3.7
 18000 -22.1  -7.8  315  56 29   7.7   4.2 | -19.9  -3.8  300  49 25   7.0   3.8
 17500 -20.4  -4.7  315  53 27   7.7   4.2 | -18.4  -1.1  295  48 24   7.1   3.9
 17000 -19.2  -2.6  315  51 26   7.7   4.2 | -17.2   1.0  295  45 23   7.8   4.3
 16500 -18.1  -0.6  315  51 26   7.7   4.2 | -16.1   3.0  290  43 22   7.8   4.3
 16000 -16.9   1.6  310  49 25   7.9   4.3 | -14.9   5.2  290  41 21   7.4   4.1
 15500 -15.7   3.7  310  44 23   7.9   4.3 | -13.8   7.2  290  40 21   7.4   4.1
 15000 -14.5   5.9  310  40 21   8.8   4.8 | -12.7   9.1  290  39 20   7.3   4.0
 14500 -13.1   8.4  310  40 21   9.1   5.0 | -11.6  11.1  290  38 20   7.3   4.0
 14000 -11.7  10.9  305  41 21   9.0   4.9 | -10.5  13.1  290  37 19   7.0   3.8
 13500 -10.4  13.3  310  42 22   8.8   4.8 |  -9.5  14.9  290  37 19   6.6   3.6
 13000  -9.1  15.6  310  44 23   8.4   4.6 |  -8.5  16.7  295  37 19   6.4   3.5
 12500  -7.9  17.8  310  45 23   7.6   4.2 |  -7.6  18.3  295  39 20   6.1   3.3
 12000  -6.8  19.8  310  46 24   7.4   4.1 |  -6.7  19.9  295  42 22   5.7   3.1
 11500  -5.7  21.7  310  46 24   6.7   3.7 |  -6.0  21.2  295  39 20   4.9   2.7
 11000  -4.7  23.5  310  45 23   5.7   3.1 |  -5.2  22.6  295  36 19   5.1   2.8
 10500  -4.1  24.6  305  44 22   3.7   2.0 |  -4.5  23.9  295  35 18   5.3   2.9
 10250  -3.8  25.2  305  43 22   4.3   2.3 |  -4.1  24.6  295  34 18   5.7   3.1
 10000  -3.5  25.7  305  42 22   2.3   1.2 |  -3.7  25.3  295  34 17   4.6   2.5
  9750  -3.5  25.7  300  40 21   2.2   1.2 |  -3.4  25.9  295  32 16   5.3   2.9
  9500  -3.2  26.2  300  38 20   4.2   2.3 |  -2.9  26.8  295  28 15   6.9   3.8
  9250  -3.0  26.6  295  36 18   3.9   2.2 |  -2.4  27.7  295  25 13   6.5   3.6
  9000  -2.7  27.1  290  34 17   5.7   3.1 |  -1.9  28.6  295  22 11   7.8   4.3
  8750  -2.2  28.0  290  32 16   7.9   4.3 |  -1.3  29.7  295  20 10   9.3   5.1
  8500  -1.6  29.1  290  30 15   8.2   4.5 |  -0.6  30.9  300  19 10   9.5   5.2
  8250  -1.0  30.2  290  28 14   8.8   4.8 |   0.1  32.2  300  17  9   9.6   5.2
  8000  -0.3  31.5  290  26 14  10.2   5.6 |   0.8  33.4  300  16  8   9.8   5.4
  7750   0.4  32.7  290  25 13   8.9   4.9 |   1.5  34.7  300  16  8   9.7   5.3
  7500   1.0  33.8  290  24 12   7.9   4.3 |   2.3  36.1  305  15  8   9.6   5.2
  7250   1.6  34.9  290  23 12   8.8   4.9 |   3.0  37.4  305  15  8  10.1   5.5
  7000   2.3  36.1  285  21 11   9.6   5.3 |   3.8  38.8  305  15  8  10.6   5.8
  6750   3.0  37.4  285  19 10   8.3   4.6 |   4.5  40.1  305  15  7   9.9   5.4
  6500   3.5  38.3  285  17  9   8.5   4.6 |   5.3  41.5  305  14  7  10.1   5.5
  6250   4.2  39.6  280  15  8  10.0   5.5 |   6.1  43.0  305  14  7  11.2   6.2
  6000   5.0  41.0  280  13  7  10.2   5.6 |   6.9  44.4  305  13  7  11.0   6.1
  5750   5.7  42.3  275  12  6   9.6   5.3 |   7.7  45.9  310  13  7  11.6   6.4
  5500   6.4  43.5  275  10  5  10.1   5.6 |   8.8  47.8  310  12  6  17.9   9.8

           03/24/2015 at 1500 MDT          |       03/24/2015 at 1800 MDT
                                           |
K index... +5.3  LI... +278.1              | K index... +13.8  LI... +276.5
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... M
                                           |
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  265  32 17   0.2   0.1 | -55.2 -67.4  270  33 17   0.4   0.2
 45000 -54.6 -66.3  270  47 24   0.3   0.2 | -54.6 -66.3  270  49 25   0.5   0.3
 40000 -58.9 -74.0  280  62 32  -3.1  -1.7 | -60.5 -76.9  275  62 32  -4.3  -2.4
 38000 -60.1 -76.2  280  67 34   0.8   0.4 | -61.9 -79.4  275  65 33   2.7   1.5
 36000 -59.5 -75.1  280  64 33   0.9   0.5 | -60.2 -76.4  275  61 32   2.9   1.6
 34000 -58.4 -73.1  280  62 32   9.3   5.1 | -57.8 -72.0  275  57 29   9.5   5.2
 32000 -52.6 -62.7  280  63 33   9.7   5.3 | -52.2 -62.0  280  54 28   9.3   5.1
 30000 -46.9 -52.4  280  64 33   7.7   4.2 | -46.8 -52.2  280  51 26   7.8   4.3
 29000 -44.5 -48.1  280  65 34   7.9   4.3 | -44.4 -47.9  280  54 28   8.0   4.4
 28000 -42.2 -44.0  280  66 34   7.9   4.3 | -42.0 -43.6  280  57 29   8.0   4.4
 27000 -39.8 -39.6  280  68 35   7.9   4.3 | -39.6 -39.3  280  60 31   8.1   4.4
 26000 -37.4 -35.3  285  65 34   8.1   4.5 | -37.1 -34.8  280  59 30   8.4   4.6
 25000 -34.9 -30.8  285  62 32   8.1   4.5 | -34.5 -30.1  280  57 29   8.4   4.6
 24000 -32.5 -26.5  285  59 30   8.1   4.5 | -32.0 -25.6  280  56 29   8.4   4.6
 23000 -30.1 -22.2  290  57 29   8.2   4.5 | -29.5 -21.1  280  55 28   8.5   4.7
 22000 -27.6 -17.7  290  56 29   8.2   4.5 | -26.9 -16.4  280  54 28   8.5   4.7
 21000 -25.2 -13.4  290  55 28   8.1   4.4 | -24.3 -11.7  280  53 27   8.0   4.4
 20000 -22.8  -9.0  290  54 28   8.0   4.4 | -22.2  -8.0  285  52 27   7.0   3.8
 19500 -21.6  -6.9  290  53 27   8.0   4.4 | -21.2  -6.2  285  52 27   7.0   3.9
 19000 -20.4  -4.7  290  53 27   8.0   4.4 | -20.1  -4.2  285  52 27   7.0   3.9
 18500 -19.2  -2.6  290  52 27   7.9   4.3 | -19.1  -2.4  285  51 26   6.9   3.8
 18000 -17.6   0.3  290  50 26   6.9   3.8 | -18.2  -0.8  285  51 26   5.2   2.8
 17500 -16.6   2.1  290  49 25   6.8   3.7 | -17.1   1.2  285  50 26   5.4   2.9
 17000 -15.6   3.9  290  48 24   6.4   3.5 | -16.3   2.7  285  49 25   5.6   3.1
 16500 -14.7   5.5  290  46 24   6.5   3.5 | -15.4   4.3  285  49 25   5.5   3.0
 16000 -13.7   7.3  290  45 23   6.2   3.4 | -14.5   5.9  285  48 25   6.9   3.8
 15500 -12.8   9.0  290  43 22   6.2   3.4 | -13.5   7.7  285  47 24   6.8   3.8
 15000 -11.8  10.8  290  42 22   6.4   3.5 | -12.5   9.5  285  46 24   7.2   3.9
 14500 -10.9  12.4  290  41 21   6.4   3.5 | -11.4  11.5  285  44 23   7.3   4.0
 14000  -9.9  14.2  290  40 21   6.2   3.4 | -10.3  13.5  285  42 22   7.5   4.1
 13500  -9.0  15.8  290  39 20   6.1   3.3 |  -9.2  15.4  280  40 20   7.6   4.2
 13000  -8.1  17.4  285  39 20   6.1   3.3 |  -8.1  17.4  280  37 19   7.7   4.2
 12500  -7.2  19.0  285  37 19   6.1   3.3 |  -6.9  19.6  275  34 18   7.7   4.2
 12000  -6.3  20.7  285  35 18   6.0   3.3 |  -5.8  21.6  270  31 16   7.8   4.3
 11500  -5.5  22.1  285  30 15   5.8   3.2 |  -4.6  23.7  270  28 14   8.1   4.4
 11000  -4.6  23.7  280  24 12   6.0   3.3 |  -3.4  25.9  265  24 13   7.8   4.3
 10500  -3.7  25.3  280  19 10   5.9   3.2 |  -2.3  27.9  265  21 11   6.7   3.7
 10250  -3.2  26.2  280  17  9   8.2   4.5 |  -1.8  28.8  265  19 10   9.4   5.2
 10000  -2.5  27.5  280  14  7  10.1   5.5 |  -0.9  30.4  260  17  9  10.6   5.8
  9750  -1.8  28.8  280  13  7   8.8   4.8 |  -0.3  31.5  260  16  8   8.0   4.4
  9500  -1.2  29.8  285  11  6   8.7   4.8 |   0.3  32.5  255  14  7   8.1   4.4
  9250  -0.5  31.1  285  10  5   8.7   4.8 |   0.9  33.6  255  12  6   7.9   4.3
  9000   0.2  32.4  285   9  5   9.4   5.2 |   1.5  34.7  250  10  5   7.8   4.3
  8750   0.9  33.6  285   9  4  10.1   5.5 |   2.1  35.8  245   9  5   8.2   4.5
  8500   1.6  34.9  285   8  4  10.0   5.5 |   2.7  36.9  245   8  4   8.2   4.5
  8250   2.4  36.3  290   8  4  10.2   5.6 |   3.4  38.1  240   6  3   9.0   4.9
  8000   3.2  37.8  290   8  4  10.4   5.7 |   4.1  39.4  235   5  3  10.3   5.6
  7750   3.9  39.0  290   8  4   9.7   5.3 |   4.8  40.6  235   5  3   9.7   5.3
  7500   4.6  40.3  290   8  4   9.1   5.0 |   5.5  41.9  235   5  2   8.6   4.7
  7250   5.3  41.5  290   7  4  10.1   5.6 |   6.2  43.2  235   4  2  10.0   5.5
  7000   6.1  43.0  290   7  4  11.1   6.1 |   7.0  44.6  235   4  2  11.4   6.3
  6750   6.9  44.4  290   7  4   9.7   5.3 |   7.8  46.0  235   4  2   9.3   5.1
  6500   7.6  45.7  295   7  4   9.4   5.2 |   8.4  47.1  235   4  2   8.6   4.7
  6250   8.4  47.1  295   7  3  10.7   5.9 |   9.1  48.4  235   4  2  10.2   5.6
  6000   9.2  48.6  295   7  3  10.7   5.8 |   9.9  49.8  230   4  2  10.6   5.8
  5750  10.0  50.0  295   6  3  11.5   6.3 |  10.7  51.3  230   4  2  10.0   5.5
  5500  11.0  51.8  295   6  3  18.1   9.9 |  11.4  52.5  230   3  2  10.3   5.6
________________________________________________________________________________

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 near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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