Troy Kimmel Weather

Forecasting Austin and South Central Texas Weather Since 1984

TK’s Special Briefing…. (100pm CT-Sun/14Jun2015)

Austin / Travis County and South Central Texas Weather Statement #2
Prepared by UT University/Incident Meteorologist Troy Kimmel
100pm CT – Sunday / 14 June 2015

.. Flash Flood Watch and Heavy Rain Potential Today into Tonight ..
.. Tropical Weather Update … Continuing to Watch the Yucatan System …

Please note that the heavier rain we’ve seen across the area this morning is NOT
directly associated with the tropical weather system over the Yucatan… I’m dealing with
these as separate systems/issues ….

Flash Flood Watch update:

NWS Austin-San Antonio / FLASH FLOOD WATCH until 12 midnight tonight for all
counties in the IH35 corridor.

Rain showers and thunderstorms, that developed in the predawn to sunrise hours this
morning, produced some heavier rainfall totals in Caldwell, Travis and Hays Counties
this morning. Several flash flood warnings were issued by NWS/Austin-San Antonio although,
in general, rainfall in Travis County was two inches of less while somewhat heavier totals
were noted in Hays and Caldwell counties. reports that only 56 low water
crossings were impacted (out of 1016 areawide) with only a couple impacted in Travis

The NWS/Austin-San Antonio has issued a FLASH FLOOD WATCH valid until 12
midnight tonight for all of the area.

As we head into the afternoon hours, focus is drawn to developing rain showers and
thunderstorms to our southwest from San Antonio to Hondo northward to near
Fredericksburg. The  NOAA NESDIS Satellite folks have issued a  Satellite Precipitation
Estimate update concerning this area and areas primarily south of the Austin area..

The discussion is technical in nature but does mention the possibility of additional heavier
rains this afternoon in areas impacted by rain earlier today. If you care to read this
discussion.. here is the link to the SPENES message/graphics… .

Remember… a FLASH FLOOD WATCH remain in effect for the afternoon into tonight
so please remain weather aware. Remember.. “Turn Around, Don’t Drown.”

Tropical weather update:

There has been little change in the disturbed area of weather is located over just off the
northwest coast of the Yucatan Peninsula. The NWS/National Hurricane Center is now advising
all interests in the northwestern Gulf of Mexico to monitor the progress of this system..


According to the forecasters at the National Hurricane Center (NHC) in their latest outlook at
1pm CDT…
A surface trough of low pressure has moved off of the Yucatan peninsula and into the southern
Gulf of Mexico this afternoon. The system is accompanied by an area of thunderstorms and winds
to near gale force well to the east of the trough, but it does not yet have a well-defined closed
circulation. This weather system is expected to move northwestward over the next couple of
days across the western Gulf of Mexico, where upper-level winds are forecast to gradually
become more favorable for tropical cyclone formation. An Air Force Reserve Unit reconnaissance
aircraft will investigate the system late this afternoon, with another mission planned for Monday
morning. Interests in and along the northwestern Gulf of Mexico should monitor the progress of
this system.
* Formation chance through 48 hours…high…70 percent
* Formation chance through 5 days…high…70 percent

A couple things to remember as we watch this system…
(1) The NHC’s chance of future development for this system has increased to 70%.
(2) Typically (in other words, climatologically) we must watch the Gulf of Mexico for early hurricane
season systems.. we are in that early part of the season.
(3) The Gulf of Mexico waters are quite warm with lots of potential latent heat to contribute for any
tropical development (if it occurs)
(4) 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 tonight into Monday.

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 in the next day or two.

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.

The latest NWS/Weather Prediction Center Quantitative Precipitation Forecast (QPF)
from now through the next five days.. please notice forecast precipitation amounts of 5 to 6  inches or more
around the Houston/Galveston areas of southeast Texas… with averages around 1 to 3 inches across the
IH35 corridor area and counties eastward…

Please let this be a “heads up” for everyone as we continue through the latter part of our weekend
and start to think about what appears to be a busy weather work week ahead for central and
eastern Texas.

Continuing to monitor… tk