Troy Kimmel Weather

Forecasting Austin and South Central Texas Weather Since 1984

TK’s Special Weather Briefing….

Austin / Travis County and South Central Texas Weather Update #2
Prepared by Incident Meteorologist Troy Kimmel (
1045pm CDT – Thursday / 21 November 2013

.. Cold Front Update ..

Late this Thursday night.. the arctic cold front is moving faster south southeastward
that my early statement indicated. At 1045pm.. the cold front is along a line from about
30 miles east of Dallas southwestward to just west of Waco to just north of Lampasas
into northwest Llano county /just northwest of Llano/ to Mason then southwestward to
just south of Junction.

Temperatures in Austin at 10pm are still holding in the low and middle 70s… the
temperature in Brownwood about 50 miles northwest of the front is 45 degrees with
temperatures in the 30s as far south as Abilene and the northwest part of the Dallas
Fort Worth metroplex.

Update before retiring for the night…
… the front will pass through the Austin and IH35 corridor counties by about 2am with
scattered to numerous rain showers and thunderstorms. The Friday calendar day
high temperature will happen right around 2am just before the cold frontal passage.
Temperatures will rapidly fall into the 40s within an hour or two after cold frontal
passage with temperatures falling into and holding in the upper 30s to near 40 for all
areas during the day tomorrow. Light rain will continue through the day with gusty
north winds and wind chills in the 20s and 30s.

I’ll continue to keep you informed… tk

Austin / Travis County and South Central Texas Weather Update
Prepared by Incident Meteorologist Troy Kimmel (
505pm CDT – Thursday / 21 November 2013

.. Much Colder Modified Arctic Air Headed South into the Area with a Possibility of Some Winter Precipitation ..

Late afternoon on this Thursday.. a strong cold front is moving southward along a line from just northwest
of Denton, just south of the Red River in north Texas, southwestward and westward to about 25 miles north
of Abilene to about halfway between Midland and Lubbock. Temperatures are in the upper 70s to near 80
at San Angelo and Abilene and quickly fall into the 20s over the Texas panhandle behind the front. The center
of the modified arctic air mass is a high pressure area.. with surface pressures just over at 1040 millibars..
located over North Dakota and Montana. Temperatures are slightly below zero to single digits under this
high pressure area over North Dakota.

The front should continue southward to move through the Austin and south central Texas area in the
3 to 4 a.m. time period on Friday morning.. a little earlier than I earlier expected. Temperatures will fall
from the upper 60s to near 70 just ahead of the front and then fall quickly into the low and mid 40s by the morning
rush hour Friday and then settle to near 40 degrees for the remainder of the day Friday with gusty north
winds and wind chills in the 30s. Air temperatures will fall into the 30s Friday night and then barely rise into the 40s
on Saturday. The much colder than normal air mass will continue to dominate our weather through the remainder of
the weekend and even into early next week.

This is complicated by the fact that as the first in a series of an upper level disturbance, over the western USA,
moves eastward over on top of this southward moving shallow wedge of modified arctic air tomorrow into tomorrow
night and Saturday, an overrunning  pattern persists as moisture overruns  the colder air at the surface.
Once this system moves eastward, we’ll see a little bit of a lull in precipitation later Saturday night into early
Sunday before another strong upper air low pressure moves overhead and enhances precipitation in the Sunday
into Sunday night and early Monday morning time period.  How cold this air mass will be when it settles into the
area is increasingly becoming a concern with there being some risk late Friday night into Saturday morning that
sleet could mix with light rain in areas north through west of the Austin area. The biggest concern, however, may be
with the secondary system later Sunday into Sunday night and early Monday as temperatures may be closer to critical
levels and there may be a better chance of some frozen precipitation in north and western parts of our area.

A couple of things for everyone to note… numerical computer models are notoriously bad in forecasting the intensity
of the shallow arctic cold air masses when they reach as far south as 30 degrees latitude (the Austin Area) and they are
also bad in timing the actual cold frontal passage. In this case, I think the cold front will be a little earlier than we were
earlier thinking and, I’m also concerned that temperatures may indeed be a bit colder than we’re thinking. Therefore my
increasing concern over the weekend into early next week as these precipitation producing upper air disturbances glide
along above the much colder surface air.

As of this evening…
NWS/San Angelo has issued a WINTER STORM WATCH for central and northwestern parts of their area…
Details/maps here…
NWS/Fort Worth has issued a WINTER WEATHER ADVISORY for the western parts of their forecast area…
Details/maps here…
There are no other watches/advisories/warnings in effect…
NWS/Austin-San Antonio has mentioned a sleet/rain mix possibility for our Hill Country counties.. including Burnet..
Blanco.. Llano and Gillespie Counties over the weekend.

Bottom line… I would urge all local interests to closely monitor the latest forecasts and possible new watches/advisories
and warnings that may be necessary over the next few days as we get a better handle on the intensity of the cold air
intrusion that’s headed this way and the upper air disturbances that could make our lives interesting over the next few days.

Once the last upper air disturbance departs to the east of the area by late Monday into Tuesday of next weekend,
we’ll see clouds break and rain chances diminish by Tuesday with increased sunshine and slightly warmer temperatures
– highs in the 50s to near 60 degrees – into Wednesday and Thursday /Thanksgiving Day/ of next week.

I’ll continue to monitor…  tk