403 
 WTPZ42 KNHC 212034
 TCDEP2
 
 TROPICAL STORM FRANK DISCUSSION NUMBER   1
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP072016
 400 PM CDT THU JUL 21 2016
 
 A 1600 UTC ASCAT-B scatterometer pass indicated that the weather
 system located off the coast of Mexico has developed a well-defined
 center of circulation, and maximum winds were around 40 kt.  Based
 on these data, advisories are being initiated on Tropical Storm
 Frank, the sixth tropical storm to form in the eastern Pacific this
 month.  Frank currently has broken convective outer banding, but a
 burst of convection is developing near the estimated center.
 
 With the recent formation, the initial motion is somewhat uncertain
 but is estimated to be northwestward, or 305/12 kt.  Frank is
 located to the south of a large and strong mid-level anticyclone
 which is centered over the Southern Plains of the United States.
 Although ridging will remain across the southern U.S. and northern
 Mexico, the main center of the anticyclone is expected to migrate
 westward over the Pacific Ocean during the next 48 hours, leaving a
 minor break in the ridge near the Baja California peninsula.  As a
 result, Frank is expected to maintain a northwestward heading for
 the entire forecast period but with a gradual decrease in forward
 speed.  There is a normal amount of spread in the track guidance,
 and the initial NHC forecast is very near the various multi-model
 consensus aids.  Although the track is currently off the coast of
 Mexico, there is still enough uncertainty that interests in the
 southern portion of the Baja California peninsula should monitor
 the progress of Frank.  In fact, based on the wind speed
 probabilities, there is currently a 1-in-4 chance of tropical storm
 force winds affecting locations in extreme southern Baja California
 Sur during the next 5 days.
 
 Frank is currently over warm SSTs over 29C, and waters are expected
 to remain warm for the next four days or so.  Although some
 vertical shear could persist for much of the forecast period, the
 statistical-dynamical guidance and the HWRF show fairly quick
 strengthening over the next few days.  The NHC intensity forecast
 follows suit and is near the higher end of the guidance, making
 Frank a hurricane in about 36 hours.  Some weakening is anticipated
 after day 3 due to cooler waters and the possible continued shear.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  21/2100Z 14.9N 104.0W   40 KT  45 MPH
  12H  22/0600Z 16.0N 105.4W   50 KT  60 MPH
  24H  22/1800Z 17.2N 107.1W   60 KT  70 MPH
  36H  23/0600Z 18.2N 108.6W   65 KT  75 MPH
  48H  23/1800Z 19.1N 110.0W   70 KT  80 MPH
  72H  24/1800Z 20.8N 112.2W   70 KT  80 MPH
  96H  25/1800Z 22.3N 113.7W   65 KT  75 MPH
 120H  26/1800Z 23.5N 115.2W   55 KT  65 MPH
 
 $$
 Forecaster Berg