ZCZC MIATCDAT3 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM COLIN DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032016
1000 AM CDT MON JUN 06 2016

The satellite presentation of Colin does not resemble that of a
classical tropical cyclone, with the thunderstorm activity and
strong winds well to the east of the center.  Satellite, buoy, and
the earlier aircraft data indicate that the center, such as it is,
is within a large area of light and variable winds. In fact, several
small swirls are seen rotating within a larger cyclonic gyre.  The
initial wind speed is maintained at 45 kt, based on the overnight
aircraft observations.  The next reconnaissance aircraft will be in
the system around 18z.

The strong southwesterly shear and very poor organization of the
system suggest that significant strengthening is not likely before
Colin reaches the coast of Florida later today.  The global models
unanimously show some deepening when the cyclone moves near the
coast of the southeastern United States, likely due to
interaction with a mid- to upper-level trough over the eastern
United States.  Colin is forecast to complete extratropical
transition in about 48 hours.

The somewhat uncertain initial motion estimate is 010/14 kt. Colin
is expected to accelerate northeastward later today.  On Tuesday,
Colin is expected to move northeastward at an even faster forward
speed as it becomes embedded in strong southwesterly flow ahead of
a large deep-layer trough over the northeastern United States.  The
NHC track forecast has been nudged slightly northward from the
previous advisory to be closer to the middle of the tightly
clustered track guidance.

Due to the displacement of the strong winds and heavy rainfall from
the center of Colin, it is important to not focus on the exact
forecast track, or on the time or location of landfall.  Heavy
rainfall, strong winds, and coastal flooding will begin affecting
portions of the Florida Peninsula this afternoon well in advance of
the center's nearing the coast.

It should be noted that Colin could lose its status as a tropical
cyclone while impacts are still occurring along the coast.  In this
case, NHC would anticipate continuing advisories and warnings on
the post-tropical cyclone.

FORECAST POSITIONS AND MAX WINDS

INIT  06/1500Z 27.0N  87.0W   45 KT  50 MPH
 12H  07/0000Z 29.6N  84.6W   45 KT  50 MPH
 24H  07/1200Z 32.8N  79.5W   45 KT  50 MPH
 36H  08/0000Z 36.3N  72.0W   50 KT  60 MPH
 48H  08/1200Z 40.2N  62.1W   50 KT  60 MPH...POST-TROP/EXTRATROP
 72H  09/1200Z 45.5N  43.9W   45 KT  50 MPH...POST-TROP/EXTRATROP
 96H  10/1200Z 50.0N  33.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
120H  11/1200Z 55.0N  27.5W   35 KT  40 MPH...POST-TROP/EXTRATROP

$$
Forecaster Brown

NNNN