ALL / Austin, Travis County and South Central Texas Weather Update #1
Prepared by UT University/Incident Meteorologist Troy Kimmel
330pm CT – Thursday / 09 January 2020
Graphic Courtesy: NWS/Storm Prediction Center
… Strong Upper Level Low Pressure Disturbance Crossing Area
with Severe Thunderstorm Risk Tomorrow Afternoon into Tomorrow Night …
Low level moisture is increasing this afternoon over our area in advance of a very strong/vigorous upper level low pressure disturbance and associated strong surface cold front that will surge eastward over our area in the Friday afternoon into Friday night time period. A risk of severe thunderstorms will accompany the passage of the system locally.. mainly in the 4pm to 12 midnight time period tomorrow.. as strong atmospheric winds, a very unstable air mass and dynamic atmospheric lift overspreads the area.
The main risks for the IH35 corridor appear to be strong/damaging straight line thunderstorm winds (since the thunderstorm system moving through the area will be linear in nature) and a smaller probability of hail and tornadoes. The greatest risk of tornadoes – perhaps a few strong and damaging – will be, in my view, in the SPC enhanced/moderate risk areas to the northeast and east of the Austin metro area over the ArkLaTex area.
Even so, we need to watch locally for any discrete supercell thunderstorms (storms that develop by themselves away from other storms in the line or around breaks/bows in the line).. these thunderstorms, especially in areas along and east of the IH35 corridor, could become tornadic.
Overall, these thunderstorms should be quite progressive and will move east of the area pretty quickly by midnight tomorrow night to daybreak Saturday morning so the threat of flooding should be quite localized especially given the on going drought conditions over the area. Rainfall of 1/4 to 1/2 inch appear to be likely with isolated higher totals of 1 to 2 inches in areas east of the IH35 corridor.
As mentioned above, with the passage of the strong cold front and its associated wind shift after midnight tomorrow night and by daybreak Saturday, the severe weather risk will quickly end west-to-east as skies clear and much cooler/drier air moves into the area.
This is a bit early in the season for severe weather for south central Texas and the IH35 corridor, so encourage you to become more weather aware and PLEASE take a few minutes and look at my notes in reference to terminology and having multiple sources of weather below.
I’m continuing to monitor and will keep you updated.
tk
Reminders…
I encourage everyone to be weather aware. Know, in advance, the difference between a
NWS issued WATCH, ADVISORY and WARNING.
Always have at least two methods of getting current weather information..
.. follow me AND activate notifications on Twitter .. @troykimmelwx ..
.. have your NWS All Hazards Weather Radio properly set so it can receive and activate
when NWS watches and warnings are issued ..
.. make sure the WEA alerts are activated in your settings on your smart phone ..
.. go to the NWS Austin-San Antonio website at weather.gov/ewx ..
.. go to http://mesonet.agron.iastate.edu/cgi-bin/afos/retrieve.py?pil=warewx&limit=20&fmt=html
for a chronological text listing (most current at the top but note the page doesn’t auto-refresh, you must refresh page manually) of NWS Austin-San Antonio watches, advisories and warnings..