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Record low Friday morning at ABIA

March 6th, 2015 at 7:34 am by under Weather

3-6 rec low

Clear skies, calm winds and very dry Arctic air allowed for a new record low temperature this morning at Austin-Bergstrom International Airport. Some creek bottoms in the Hill Country were as cold as 15 degrees.

The Austin metro area also dipped into the 20s this morning — our coldest start since January 8!


Elusive El Nino finally arrives

March 5th, 2015 at 9:45 am by under Weather

sst blog

NOAA - March 5, 2015

The long-anticipated El Niño has finally arrived, according to forecasters with NOAA’s Climate Prediction Center. In their updated monthly outlook released today, forecasters issued an El Niño Advisory to declare the arrival of the ocean-atmospheric phenomenon marked by warmer-than-average sea surface temperatures in the central Pacific Ocean near the equator.

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Latest probabilities of ice Thursday morning

March 4th, 2015 at 9:36 am by under Weather
Courtesy: NOAA/NWS

Courtesy: NOAA/NWS

The latest forecast from the National Weather Service winter weather models indicate a 50-60% chance of bridge/overpass icing Thursday morning throughout much of the Austin metro area.

Though a widespread icing event is not currently anticipated in Austin early Thursday, we will likely see some slick overpasses and bridges — especially north and west of town. More widespread problems will likely materialize in the Hill Country and on rural roads.

Use caution on area roads Thursday morning and stay on top of this developing winter storm on-air, online and with our free KXAN Weather app.


Risk of icy roads in some areas early Thursday

March 3rd, 2015 at 7:38 am by under Weather

3-3 snow ice fcast

Following a brief warm-up today and early Wednesday afternoon, we are tracking our next blast of Arctic air set to bring yet another threat of ice and snow.

The cold air is forecast to arrive late Wednesday afternoon. As a storm system approaches Texas from the west, moisture overriding the cold air will increase cold rain Wednesday evening–eventually turning to freezing rain and sleet in many communities along and west of I-35.

wpc bllog

Current National Weather Service forecasts indicate a 40-50% chance of accumulating ice on elevated roads in the Austin metro area early Thursday.

Here’s what our partners at the National Weather Service in New Braunfels have to say:

Headline:

…Another round of frozen precipitation is possible Wednesday evening through Thursday morning…

Area of Concern:

Cold Arctic Air - All of South Central Texas

Frozen Precipitation - Mainly the Hill Country, areas northwest of San Antonio,  and northern parts of I-35 corridor including the greater Austin metro area (Travis and Williamson Counties).

Threats & Impacts:

Ice Accumulations: There is a high likelihood that areas of the Hill Country will see ice accumulations.  It is too early to tell exactly how much.  As in the previous winter events the past several weeks, areas farther east including the I-35 corridor will have a threat for icing but temperatures may not be cold enough to support widespread ice development outside of bridges and overpasses. Stay tuned, that could change.

Impacts:  Mainly travel impacts expected at this time.  Bridge/overpasses closures, some ice on less traveled roads. Numerous traffic accidents.  At this time we are not expecting widespread power outages.

Timing and Overview:

6 PM Wednesday through Noon Thursday.

The next front will arrive in South Central Texas Wednesday Afternoon with an arctic airmass behind it. Temperatures will fall behind the front with the Hill Country reaching freezing around 9 pm Wednesday. Northern Portions of the I-35 corridor will fall below freezing shortly after midnight…this includes the Austin metro area. An upper level storm system will create high precipitation chances Wednesday morning through Thursday morning. Due to the upper level winds we will get more lift with this weather system than previous systems, so some scattered thunderstorms will be possible during the day Wednesday before the front arrives.

Based on our current forecast a Sleet and Freezing Rain mix will begin across the Hill Country Wednesday night stretching from a Del Rio to San Antonio to Giddings line by midnight. This will then transition over to a sleet and snow mix by Thursday morning for areas north of Highway 90. As in past events the best chance for ice accumulation and impacts will be in the Hill Country and along the northern I-35 corridor where temperatures will be coldest. Temperatures are expected to warm above freezing by noon on Thursday and rain chances begin to taper off Thursday afternoon.

The question of just how much precipitation will fall, the exact type of precipitation, and just how far south the freezing line will get, are all still questions that are being fine tuned with each forecast package. As in past events this year, far southern and eastern areas will likely just see cold rain, western and northern areas (higher terrain) will probably get some ice, and areas in the middle (I-35 from San Antonio to Austin) will be stuck in the middle and could go either way.  In cases like this, many times I-35 is literally a dividing line…colder air and ice chances in the hills, and cold rain east of I-35.  Where it is forecast to be cold enough…such as the Hill Country, we can expect some ice formation especially on exposed surfaces like bridges and overpasses.

Watch the forecast closely over the next few days…there will likely be adjustments to the above forecast information.  There is a high likelihood that portions of the area will be under some sort of winter weather advisory/watch/warning during this Wed Evening - NoonThu time frame.

Confidence:

Arctic Air – High

Frozen Precipitation Amounts/Area - Moderate

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Currently, forecast low temperatures in Austin will support patchy, but not widespread, icing during the Thursday morning commute. Stay tuned for updates on KXAN, KXAN.com, and our free KXAN Weather app on your smartphone.


Latest wintry weather update

February 28th, 2015 at 9:16 am by under Weather

A Winter Storm Warning is in effect until noon for Travis and Williamson counties, where 1/10″ ice accumulation is possible on heavily-traveled metro roadways. A Winter Weather Advisory is highlighted elsewhere in pink: Hays and Blanco counties will expire at 10 AM on Saturday, and all other counties are set to expire at noon. With temperatures rising into the 40s everywhere this afternoon, the First Warning Weather Team does not anticipate that any watches, warnings or advisories will be issued after that time.

2-28 WWA

 

Here is the latest from the National Weather Service:

Stay off the roadways before noon if possible. Even though temperatures should rise above freezing in the metro and Hill Country between 10 AM and noon, early morning ice will still take some time to melt off the streets. Exposed and elevated areas will bear the brunt of the icy impacts: bridges, toll roads, overpasses, patios and walkways.


Latest wintry weather update

February 27th, 2015 at 9:30 am by under Weather

Though the Austin metro area has been pulled out of the threat for wintry precipitation for today and tomorrow, the Hill Country may still have some slick spots by Saturday morning. Here’s the latest breakdown from our friends at the National Weather Service:

Headline:

Another round of wintry mixed precipitation on the way from this morning through 10 am Saturday for higher elevations in the Hill Country, and the far western portion of Williamson County.

Area of Concern:

The primary area will be the Hill Country, roughly from Burnet to Fredericksburg to Kerrville to Rocksprings. Another area of concern is is the far western end of Williamson County, from Florence down to Liberty Hill. Metro Austin, the I-35 corridor, and Metro San Antonio are now completely out of the winter weather threat.

Threats & Impacts:

Expected Accumulations: We expect very light amounts — 1/4 inch or less of snow in the Hill Country, accompanied by only a few hundredths of sleet or freezing rain/drizzle in that area, and in far western Williamson County.

Impacts:  The primary impacts are expected to be patchy slippery spots, primarily on bridges, overpasses, and other elevated surfaces (e.g., picnic tables).

Timing and Overview:

Moist Gulf air will continue to lift over cold air near the ground to produce the wintry mix of precipitation. As with the other events this winter, we expect precipitation amounts to be light, and generally be more of a travel nuisance than any threat to safety. All of the precipitation should end by 10 am on Saturday, and temperatures will warm above freezing then. Please see the graphics below.

Confidence:

High for the temperatures being cold, High for the precipitation mix and amounts.

Stay in touch with the latest weather forecasts on KXAN.com.


Weather balloon downed in Dallas due to icing

February 25th, 2015 at 9:41 am by under Weather
dfw sounding

Plot of the second, more successful upper-air sounding (weather balloon) launch attempt from Dallas-Ft. Worth this morning. Small warm layer aloft explains why Dallas saw lots of rain before the snow transition.

Twice a day at National Weather Service offices nationwide (and around the world), meteorologists release weather balloons that rise through the depth of the atmosphere and transmit data back to the ground that helps us forecast the weather.

This morning at the Dallas NWS office, however, the balloon was not successful in doing so.

Weather balloon (Courtesy: US Navy)

Before the balloon could rise to the top of the atmosphere, where it traditionally pops since air pressures are so low that high, it actually stopped rising. Here’s what the office had to say:

“…it’s not too uncommon during conditions like this. As the 1st balloon was being released—we got a very brief, but intense downpour of sleet here at the office. ” - DFW NWS

The second weather balloon they released was successful in its climb to the top of the atmosphere.


Join KXAN at the ABC Zilker Kite Festival Sunday, March 1

February 24th, 2015 at 3:56 am by under Weather

zilker kite

Let’s Go Fly a Kite!

Join us for the 86th annual ABC Zilker Kite Festival.

MARCH 1st, 2015 Kick off spring in beautiful Zilker park in central Austin. The ABC Zilker Kite festival is FREE for everyone and benefits Communities In Schools of Central Texas.

  • FORECAST: After being rained out twice last year, the weather looks much better this year.  Expect a mostly cloudy, breezy day on Sunday with south winds of 10-20 mph and just a slight chance of a shower. Enjoy!

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Sleet or freezing rain: what’s the difference?

February 22nd, 2015 at 11:02 am by under Weather

With a Winter Weather Advisory in effect for the Hill Country and Austin metro area in the next 36 hours, you may be wondering about the sleet and freezing rain in the forecast. Are the terms not interchangeable? Do the two types of winter precipitation create any difference, once on the surface?

Here’s a scientific breakdown from our friends at the National Weather Service in Amarillo:

1 2

Boiled down, both sleet and freezing rain have droplets that go through a cold-warm-cold pattern when falling through the atmosphere.

Sleet has a large enough cold layer before the surface that it refreezes, and it hits the ground as ice pellets.

Freezing rain remains liquid until it hits a surface. It instantly freezes on the first thing it comes in contact with, be it grass or cars or roadways. That makes freezing rain the greater danger of the two types of precipitation. Even a few hundredths of an inch of ice can make hazardous driving conditions.

A Winter Weather Advisory begins in the Hill Country at midnight on February 23, 2015. That same advisory extends to the Austin metro area, including Travis, Williamson and Hays counties, at 3 AM on February 23, 2015. The advisory expires for everyone at 6 PM on Monday night. Sleet is more likely for the Hill Country with this system, though Monday night/Tuesday morning, everyone through the metro may see a bit of freezing rain. Be safe!

2-22 WWA

 


NWS update for Sunday – Monday – Tuesday

February 21st, 2015 at 10:39 am by under Weather

Thanks to a cold mass of arctic air, at KXAN we’re forecasting small ice accumulations in the Hill Country by Monday morning, with San Saba and Lampasas counties under a Winter Storm Watch starting Sunday night. Ice is most likely on elevated surfaces, like bridges and overpasses: something to keep in mind if you have to be out on the roadways Monday morning!

Here’s what the National Weather Service office has to say on the chilly intrusion:

HEADLINE…Arctic Airmass moves in Sunday…Winter Precipitation possible Monday Morning through Tuesday Morning…

AREA OF CONCERN
  • Cold Arctic Air - All of South Central Texas.
  • Chances of Frozen Precipitation Monday/Tuesday -  Mainly along and north of a line from Rocksprings-Kerrville-Burnet on Monday. The line could shift south along a Del Rio-Uvalde-New Braunfels-Giddings line by Monday night. Rest of South Central Texas needs to monitor the forecast closely as this forecast impact area could change.                                     .
 …IMPACTS
  • Cold Arctic Air - Temperatures will be well below normal with high temperatures only in the 30s and 40s on Monday.  Lows Tuesday Morning will be in the 20s and 30s.
  • Frozen Precipitation - Light icing on elevated surfaces.  Travel may be impacted especially out in the Hill Country and northern areas where temperatures will likely be coldest.
TIMING
  • Arctic air will arrive Sunday and remain in South Central Texas through Tuesday.
  • Chance of precipitation will begin shortly after the front moves through the area. Temperatures could drop below freezing for the northern Hill Country as early as Monday Morning. The freezing line will shift southeast Monday evening into Tuesday Night. Precipitation should shut off from west to east by Tuesday Morning.
CONFIDENCE… Arctic Air (High)…Frozen Precipitation amounts and area (Low)
DISCUSSION
A strong upper level ridge of high pressure is strengthening off the coast of the Western US. A strong low will develop to the east and this pattern will send a strong arctic front into South Central Texas by Sunday morning. This front will bring much colder temperatures with 30s/40s across the area Monday Morning continuing into the day Monday. At the same time, strong winds aloft will allow for lift to aid in the development of light precipitation beginning Sunday and lasting into Tuesday. The main focus will then shift to the temperature forecast. As of today, locations north of a Rocksprings to Kerrville to Burnet line will have the best chances to see freezing rain or perhaps sleet Monday morning and then again Monday night. There should be a warmup into the middle 30s for these locations in the afternoon hours. However, even colder temperatures are expected by Monday evening and Tuesday morning and locations north of a Del Rio to Uvalde to New Braunfels to Giddings line could see freezing precipitation.
We are still a few days out from this possible winter event so trying to nail down the specific times and area of greatest impact is very difficult. If temperatures are warmer or colder by even two degrees, a significant shift in the forecast will be needed. All residents need to monitor the forecast closely this weekend for possible winter weather advisories/watches/warnings.  There may be travel impacts, especially in the northern Hill Country on Monday – Tuesday.
The NWS has provided this image to go along with the discussion:
Untitled
Though Austin is in the “low probability” area for ice, it’s still something our weather team is watching. Here is our current prediction for frozen precipitation through Tuesday:
2-21 2
The metro area is right on the cusp of the line between cold rain and ice. With temperatures that will hover in the 30s all day Monday, we’re monitoring the potential for slick roads.
Ideally, the air will dry out before the coldest push of air comes through Monday night. This system still has time to shift and change, though, so keep checking back with us and the current forecast at KXAN.com.