Image Department Meteorology
Meteorology_Home Weather_Server News/Seminars
Academics Application Contact_Us

Links Disclaimer

 WTPZ42 KNHC 060250
 Tropical Storm John Discussion Number   2
 NWS National Hurricane Center Miami FL       EP122018
 900 PM MDT Sun Aug 05 2018
 Convection associated with Tropical Depression Twelve-E has
 continued to become better organized, although recent microwave
 satellite data suggest the low-level center is elongated from
 northwest to southeast.  Satellite intensity estimates from TAFB and
 SAB have increased to 35 kt, and based on these the depression is
 upgraded to Tropical Storm John.
 The initial motion is 315/7.  A westward-moving mid- to upper-level
 trough over northern Mexico has weakened the subtropical ridge over
 the northeastern Pacific, and the large-scale models are in good
 agreement that John will move northwestward at an increasing
 forward speed toward this weakness.  A complicating factor is that
 John may interact with Tropical Storm Ileana to the east.  However,
 John is much larger than Ileana, and the most likely impact of this
 interaction is that John could move a little slower than currently
 forecast.  The new forecast track is a little to the north of the
 previous track after 48 h, but is otherwise similar to the previous
 forecast.  The new track also lies just south of the cluster of
 consensus models.
 John is expected to be in an environment of very warm SSTs, low
 shear, and a moist atmosphere through about 60 h.  This environment
 is quite favorable for rapid intensification (RI), as indicated by
 high probabilities in the SHIPS RI index, and it is likely that RI
 will begin as soon as the inner core of the storm becomes better
 organized.  The NHC forecast calls for the storm to become a
 hurricane in 24-36 h and to reach a peak intensity of 95 kt in about
 three days.  After that, the forecast track takes John over rapidly
 cooling sea surface temperatures, which should cause at least a
 steady weakening.  The intensity forecast is in best agreement with
 the intensity consensus.  It should be noted, however, that the
 SHIPS and LGEM models both show more intensification than the
 official forecast and make John a major hurricane in about three
 INIT  06/0300Z 14.9N 106.2W   35 KT  40 MPH
  12H  06/1200Z 15.6N 107.0W   45 KT  50 MPH
  24H  07/0000Z 16.3N 107.9W   60 KT  70 MPH
  36H  07/1200Z 17.3N 108.9W   75 KT  85 MPH
  48H  08/0000Z 18.5N 110.3W   90 KT 105 MPH
  72H  09/0000Z 21.5N 113.5W   95 KT 110 MPH
  96H  10/0000Z 24.0N 118.0W   65 KT  75 MPH
 120H  11/0000Z 26.0N 122.0W   40 KT  45 MPH
 Forecaster Beven
Return to the Tropical Systems Page for JOHN

Back to main Tropical Weather page

This page is maintained voluntarily by the MKWC and the UHMET faculty, staff, and students.
It was last modified on: Thu, Jul 23 2020 - 2003 UTC
Send comments to: Ryan Lyman