Troy Kimmel Weather

Forecasting Austin and South Central Texas Weather Since 1984

TK’s Special Briefing… (1155am CT-Mon/15Jun2015)

Austin / Travis County and South Central Texas Weather Statement #5
Prepared by UT University/Incident Meteorologist Troy Kimmel
1155am CT – Monday / 15 June 2015

.. NWS/National Hurricane Center Issues an Update .. Other than an
Increase of Probability of Development.. No Major Changes as
Disturbed Area of Weather Races Toward the Texas Coast ..

.. Flash Flood Watch Issued for Austin Metropolitan Area and the IH35
Corridor Counties Until 7am Thursday Morning ..

.. All Interests on the Texas and Southwest Louisiana Coasts Should Remain in
Close Touch with Latest NWS Information on this Developing System in Case
Tropical Cyclone Watches or Warnings Are Issued Later Today and Tonight ..


According to the forecasters at the National Hurricane Center (NHC) in their SPECIAL
updated at 1155am CDT…

Special tropical weather outlook issued to report on results of the
aircraft reconnaissance mission.

An Air Force Reserve Unit Hurricane Hunter aircraft has been
investigating the area of low pressure in the Gulf of Mexico all
morning.  Data from the mission indicate that the circulation
is highly elongated and lacks a well-defined center.  Therefore the
system is not a tropical cyclone and advisories are not being
initiated at this time.  However, the low still has the potential to
become a tropical storm at any time before it reaches the Texas
coast sometime tomorrow.

The aircraft data do indicate that the system is producing winds of
45 mph or so to the east of the elongated trough axis, and interests
in and along the northwestern Gulf of Mexico should continue to
monitor the progress of this system.  Regardless of tropical cyclone
formation, tropical storm conditions are likely along portions of
the middle and upper Texas coast, and possible in extreme
southwestern Louisiana, Monday night and Tuesday. The system is also
likely to bring heavy rainfall with possible flooding across
portions of eastern Texas and western Louisiana.  For additional
information, please see High Seas Forecasts and products issued by
your local National Weather Service forecast office.
* Formation chance through 48 hours...high...90 percent
* Formation chance through 5 days...high...90 percent

A couple things to continue to remember as we watch this system…
(1) With this system.. in whatever form it takes..  expected to make landfall on the Texas coast
by late tonight into early Tuesday,  we will have little if any lead time should watches and
warnings become necessary.
(2) The NHC’s chance of future development for this system increased to 90%.

(3) Climatologically, we must watch the Gulf of Mexico for early hurricane season systems.. we
are in that early part of the season.
(4) The Gulf of Mexico waters are quite warm with lots of potential latent heat to contribute for any
tropical development (if it occurs)
(5) Remember that there are two things that largely determine what effect a tropical cyclone has on
a given location… first, how well developed or strong the system becomes, of course, and, secondly,
it’s exact track across the given area. There are limitless potential scenarios for this system but one
thing to remember is that if the track stays east of our area (say into southeast Texas), we will be
on what is normally the drier side of the system (especially if it becomes better developed). If it tracks
more overhead or to west and southwest of our area, we end up in what is normally the wetter part of
the system. At this moment, it appears that the first scenario (track staying east of our local IH35
corridor area) appears most likely, but we must all continue to watch this system carefully since parts
of Texas may be making preparations for a possible tropical cyclone, if this system develops over the
Gulf of Mexico, by later tonight into tomorrow.

As mentioned above, all interests along and inland along the Texas coast should be monitoring the
latest information from the NWS/National Hurricane Center as well as local NWS offices. Everyone
should be ready in case the system becomes better organized and NWS issued tropical cyclone
watches and warnings are required later tonight or tomorrow.

It is also important to remember that even if it doesn’t become better developed, the system is still
expected cause widespread rain showers and thunderstorms over the eastern half the state for the
first through middle part of the new week (depending upon exact track).

Finally, it’s important to note that the ground across the area from the IH35 corridor counties eastward
through southeast Texas (Houston area) is saturated or nearly saturated so additional rainfall that might
be associated with this approaching system will cause problems quickly.
Those problems could grow to be
quite serious in a quick period of time!!

The latest NWS/Weather Prediction Center Quantitative Precipitation Forecast (QPF)
from now through the next five days indicates forecast precipitation amounts of 6 to 7 inches or more
from Matagorda Bay northward to College Station and eastward into the Houston/Galveston areas of
southeast Texas… with averages around 2 to 3 inches across the IH35 corridor area with amounts
picking up quickly as you move eastward into the maximum rainfall area to our immediate east.

Continuing to monitor… tk