First Warning: Update on the likelihood we’ll see snow this week

Weather Blog

As we get closer to the finale of 2020, Mother Nature has one more curve ball in store for Central Texas – a potential winter storm.

The set-up

A strong storm system currently over Southern California looks to strengthen on its approach to Texas. As it nears today, increasing clouds and a few spot showers are possible. By tomorrow, a strong cold front attached to the storm will swing through helping to further increase rain chances. Wednesday and Thursday look most active with the best dynamics of lift and moisture. Widespread showers and thunderstorms, plummeting temps and breezy to windy conditions are likely area-wide heading into New Year’s Eve.

The tricky part? The very cold air packed in behind the front. As the system starts to lift away, wrap-around and lingering moisture, in combination with the cold air mass, could allow snow and wintry mix showers to develop. And that’s where the “forecasting fun” comes in.

The update

As more and more computer models have crunched the data, the likelihood for snow and wintry mix is still there, but has moved farther to the west and away from the Austin Metro. While temperatures will plummet throughout the day on New Year’s Eve, it’s looking like much of Central Texas will stay just above freezing while precipitation is falling. Meaning a very cold rain throughout the day. At this time, it is looking like temperatures won’t fall below freezing until the rain has moved out of the area right around when we’re counting down the final seconds of 2020.

Here’s a look at some of our forecast models reflecting this shift.

Model #1 – NAM

As the timing of the event is getting closer, we now have access to some of our high resolution models. Until now, we’ve been using our long range models, which do a very good job at forecasting the potential for precipitation events 3 to 7 days out, but are less reliable 1 to 2 days out. That’s when our high resolution models take over, and do an amazing job at pinpointing time, location, and precipitation type a lot better than long range models.

Take a look at the NAM model, or the North American Mesoscale Forecast System. New Year’s Eve afternoon is looking like the best time frame for wintry precipitation for Central Texas, and as you can tell, it’s not very good. We have a better chance at heavy rain and thunderstorms than of wintry weather (at this time, things can STILL change!).

FORECAST: As rain exits the Austin metro, some light wintry precip is possible for the Hill Country

Model #2: RPM

Another favored high resolution model is the RPM, or the Rapid Precision Mesoscale model. Below is the latest update from the RPM for the same time frame as the NAM above:

FORECAST: ECMWF showing wintry mix/snow possible along and west of I-35 on Thursday (12/31)

Looking forward

So what to make of it all?

If New Year’s Eve takes you out to West Texas towards El Paso, you’ll want to try and get there by tomorrow as the National Weather Service has Winter Weather Watches in effect from the Big Bend to the Permian Basin through Friday at 12:00 AM in preparation for this storm. Snowfall totals on the range from 2 to 10 inches are possible within the watch region. Travel on I-10 and I-20 will be difficult as the region digs out of the snow.

Winter Weather Watches issued for the potential of 2 to 10 inches of snow

For those wishing for a wintry end to 2020, you may have to travel a little farther west (preferably before the snow falls). Confidence is continuing to decrease for frozen precipitation in Central Texas, while confidence is remaining high for some very heavy rain. While we absolutely need the rain, this storm has the potential for some minor flooding in our low lying areas. Be advised and remember to turn around, don’t drown!

The Texas Department of Transportation is also preparing for potentially icy roadways in the Austin area this week, and began pretreating bridges and overpasses in case the wet roads freeze. Those areas in particular are the first to freeze, so TxDOT suggests as the weather move in, people drive cautiously and slow down. It also will have crews on standby to respond to icy spots.

Now would be a great time to download the KXAN Weather app for notifications on the upcoming storm (free download on Google Play or iTunes)

Stay up-to-date

Stay updated with the KXAN Weather team on social media (click links):

– Chief Forecaster Jim Spencer (Facebook & Twitter)
– Meteorologist David Yeomans (Facebook & Twitter)
– Meteorologist Kristen Currie (Facebook & Twitter)
– Meteorologist Sean Kelly (Facebook & Twitter)
– Meteorologist Mark Peña (Facebook & Twitter)

Copyright 2021 Nexstar Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Tracking the Coronavirus

Coronavirus Cases Tracker

Latest Central Texas COVID-19 Cases

More Coronavirus Live Blogs

Trending Stories

Don't Miss