Severe Threat Tonight/Sunday

Weather Alert: The Storm Prediction Center in Norman, Oklahoma has placed a large portion of north and south central Texas under an ENHANCED RISK area for severe weather through Sunday morning. 

Severe Weather Risk Areas through 6 a.m. Sunday Morning:



Severe Weather Risk Areas after 6 a.m. Sunday Morning:



>According to the Storm Prediction Center, an ENHANCED RISK of severe weather means numerous severe storms are possible...the severe storms that are able to develop will be more persistent and/or widespread...a few of those severe storms may become intense potentially producing a few tornadoes, and/or several reports of wind damage, and/or damaging hail of 1-2 inches in diameter.



>The Storm Prediction Center (SPC) has issued a TORNADO WATCH for a large portion of north central and north Texas into southeastern Oklahoma through 8 p.m. this evening. This watch does include Temple/Killeen, Waco, and Dallas/Fort Worth.



Tornado Watch Details:
>The SPC warns that a few tornadoes will be possible within and in the vicinity of the watch box, along with the potential for some isolated large damaging hail and some isolated damaging thunderstorm wind gusts to 70 mph.

>>>No watches/warnings are currently in effect for south central Texas, however, the SPC is monitoring our area closely. As of their latest forecast discussion, the SPC is giving our area a 40% chance of being placed under a weather watch over the next several hours. 

Evening/Overnight Forecast:
Scattered storms will continue to develop and move north across the area through the evening and late night hours...some of the storms that develop will become strong/possibly severe with heavy rainfall, lightning, gusty winds, some small hail, and perhaps a tornado or two. The atmosphere is ripe for severe weather and wind profiles are favorable for rotating storms to develop which may in turn allow for a tornado or two to spin up. Please keep an eye to the sky and have a way of receiving the latest watches/warnings issued by the National Weather Service. If you have turned off the severe weather alerts on your smart phones, now would be a good time to turn those back on...they may end up saving your life!

Southerly winds will remain breezy through the evening and may actually increase overnight tonight as the weather system approaches the area...think of these moist, southerly winds as fuel for the storms this evening and overnight and into Sunday morning.

Warm & moist southerly winds off of the Gulf will keep temperatures warm across the area through the overnight hours in the 70s...big temperature drop arrives behind the front Sunday morning!

Severe Weather Risk:
Our risk of severe weather is developing ahead of a potent upper level Pacific storm system and its associated Canadian Cold Front. As this system approaches and moves through the area late tonight into Sunday morning widespread showers and storms will develop. Some of the storms will have the potential of becoming severe. As the cold front moves through the area early Sunday morning, I'm expecting a line of strong storms to push from west to east across the region. This line of storms will have the potential to bring many locations within south central Texas strong wind gusts and heavy rainfall.

MUCH COLDER AIR moves in behind this weather system and cold front on Sunday with lows dropping into the 30s area wide by Monday morning!

Let's continue to remain weather aware!

Warm and Unsettled Christmas Week

Forecast Discussion:
Good Tuesday afternoon everybody. Abundant sunshine and a warm southwesterly, down-sloping wind above the surface has allowed for another well above average afternoon across south central Texas. We officially topped out at 79°F at Camp Mabry this afternoon (17 degrees above the average high of 62°F for this time of year) and 78°F at the airport (15 degrees above their average high of 63°F for this time of year). In fact, we came very close to tying the record highs at both official weather stations this afternoon...record high for this date at Mabry is 81°F set back in 1941 and 80°F at the airport set back in 1988.

Tonight/Overnight:
>>>Southerly surface wind flow increasing across the area this afternoon in response to an approaching upper air disturbance from the west. The tail end of the upper level energy with this system will skirt the area overnight and allow a weak Pacific frontal boundary (dry line) to move through the area overnight.

>>>Widespread low clouds with embedded areas of mist and/or drizzle likely across the area late tonight into early Wednesday morning ahead of this approaching weather system. A few scattered light rain showers will be possible here across south central Texas with the potential for some heavier downpours and brief thunderstorms north of our area. An isolated heavy downpour or thunderstorm cannot be completely ruled out late tonight/early Wednesday morning for areas along and east of the I-35 corridor as the Pacific Front/Dry Line crosses the area.

>>>Lows tonight will be significantly warmer across the area thanks to the southerly wind flow off of the Gulf across the area. Lows tonight will actually be warmer than our average highs for this time of year in the mid to upper 60s.

Forecast Clouds/Radar at 1 a.m. (HRRR Model)



Image above courtesy of Penn State Department of Meteorology 

Wednesday's Forecast:
>>>Widespread morning low clouds, drizzle, and scattered rain showers will give way to a mainly sunny, drier, and warmer Wednesday with highs easily expected to climb into the upper 70s to near, if not exceeding, the 80°F mark in a few locations. The west southwesterly wind and dry air behind the dry line will allow for temperatures to warm up nicely. Wednesday night/Christmas Eve morning will be cooler thanks to the drier air in place with lows expected to dip into the upper 40s to lower 50s across the area...some patchy areas of fog may develop by Christmas Eve morning (especially for areas south and east of Austin).

Enhanced risk of severe weather across the southeastern United States (hail, damaging winds, and tornadoes all possible, especially in areas shaded in orange on Wednesday)...just a head's up if you or anyone you know is traveling in that direction tomorrow



Christmas Eve (Thursday) Forecast:
Gulf moisture quickly returns to the area as a deep trough, or dip in the jet stream begins to set up across the western United States...return flow off of the Gulf will allow for moisture to come surging back up into the area and keep highs well above average for this time of year. Highs will easily manage the mid to upper 70s. A few light rain showers will be possible across the area, especially during the evening hours as southerly surface wind flow increases in response to dropping surface pressure across the plains.

>>>Highs: Mid to Upper 70s
>>>Lows: Upper 50s to lower 60s

Christmas Day (Friday) Forecast:
Cloudy and mild start to the day with temperatures near 60°F gives way to a mostly cloudy, warm, humid, and breezy afternoon with highs once again climbing well above average into the mid to upper 70s...some light rain showers will be possible during the daytime and evening hours as southerly flow continues to strengthen ahead of a deepening trough of low pressure across the western United States.

Christmas Weekend: Potentially Stormy & Finally Turning Cooler!
A large and potent upper level low pressure system and deep trough, or valley, of lower atmospheric pressure approaches the area late Christmas Day into Saturday...ahead of this approaching storm system and its associated cold front, southerly flow will persist and keep us in a mostly cloudy, humid, showery, and well above average temperature trend. As the upper level energy and its associated surface cold front cross the area late Saturday into early Sunday I'm expecting widespread showers and storms to develop across the area (moving from west to east across the area). A few of the storms will approach the strong side with heavy rainfall, lightning, gusty winds, and perhaps some small to medium sized hail. Too soon to say just how much rain we are going to receive, but upwards of 0.5 to 1.5 inches would not be out of the question. There is the potential for some drier air to move into the area and mid levels of the atmosphere ahead of this storm system. If that in fact happens, rain chances and amounts would be greatly reduced.

Texas Snow:
On the back side of this cold front and upper level low, cold Canadian Air will come pouring south into the state of Texas. The Panhandle is preparing for a big ice/snow storm...NO SNOW/ICE for central Texas, however, some much cooler air will move into the area behind the front on Sunday and stick around into the new week with highs dropping into the upper 50s and lows dropping into the 30s. We will have to continue to monitor temperature trends over the coming days and continue to monitor the very latest forecast model guidance as things will still change with this system.

Forecast Sea Level Pressure/Precipitation Intensity/Type for 6 a.m. Sunday morning:



Forecast Surface Air Temperatures for 6 a.m. Sunday morning:



Images above courtesy of Tropical Tidbits

Wishing each and every one of you a very Merry Christmas and Happy Holidays. May it be a blessed holiday for each of you spent among great friends and family. Wishing each of you the best of health, happiness, and prosperity. 

Of course I will be monitoring the weather over the next several days as you should too! Especially as we approach the upcoming holiday weekend.

Thursday Evening Update

Forecast Discussion:
Good Thursday evening everybody. Hope you are all doing well. The weekend is just around the corner.

We started the day on the cold side across the area with temperatures in the 20s and 30s. We officially bottomed out at 39°F this morning at Camp Mabry and 33°F out at the airport. Abundant sunshine and dry air in place allowed for a nice warm-up area wide this afternoon. Temperatures managed to rebound nicely into the 60s...official numbers coming in at 68°F at Camp Mabry and 66°F at the airport.

Cooler Friday:
A reinforcing shot of chilly air will move into the area overnight tonight. In response to the cool air mass moving in, highs will only manage the mid to upper 50s across the area on Friday under a sunny blue sky. We will wake up to temperatures in the 30s area wide (some areas north and west of Austin proper will receive a light freeze).

With clear skies and a dry and cool air mass in place, temperatures will be able to cool off in a hurry Friday night once the sun sets. We will wake up to temperatures in the upper 20s to lower 30s across the area by Saturday morning. Austin proper should stay above the freezing mark (32°F), however, out-lying and especially low-lying areas will have to contend with a light freeze.

Forecast Lows Friday Night/Saturday Morning:


Image courtesy of Tropical Tidbits

Weekend Forecast:
Warming trend quickly returns to the area by Saturday with highs rebounding back into the 60s after a cold start. Southerly winds will quickly return to the area ahead of an approaching upper level disturbance from the west. Temperatures Saturday night will be significantly warmer in the 40s and 50s with increasing clouds. As of right now, Sunday looks to be partly sunny, mild, and breezy with highs in the upper 60s to lower 70s.

Christmas Week: It looks to be a warm one folks and potentially wet
Rain chances return to the forecast for early next week...it's too soon to say how much rain we are going to get out of this next system, however, current forecast model guidance is wanting to keep the heaviest precipitation and highest rainfall accumulation east of the I-35 corridor. Temperatures are forecast to be well ABOVE AVERAGE for this time of year with highs in the lower to middle 70s and overnight lows in the 50s. We may cool off a bit just in time for Christmas Eve and Christmas Day, but that is not a sure thing at this point. Rain may be possible Christmas Day into Christmas weekend, we will just have to wait and see what forecast models decide to do in the coming days.

Long range forecast model guidance is indicating the potential for some colder weather by the end of the month and into the new year, however, we still have plenty of time to watch that.

Climate Prediction Center's 6-10 Day Temperature Outlook (valid Dec. 23-27, 2015)
Forecasting well above average temperatures for the central and eastern United States



Climate Prediction Center's 6-10 Day Precipitation Outlook (valid Dec. 23-27, 2015)
Forecasting wetter than normal conditions for much of the country with the exception of deep south Texas

Storms Arrive Tonight!

Good Saturday afternoon everybody. Hope you are all doing well. 

Forecast Discussion:
The large area of light rain showers with embedded areas of moderate to at times heavier downpours will continue to shift east and northeast away from the I-35 corridor for the remainder of the day. This activity was able to develop thanks to a disturbance embedded within the strong southwesterly wind flow aloft over the area in advance of a potent and deep upper level trough, or valley, of lower atmospheric pressure to our west. The main upper level low associated with this approaching storm system is currently spinning over the desert southwest (Arizona and New Mexico).

You can clearly see that counter-clockwise rotation along the Arizona/New Mexico Border in the latest visible satellite image loop...that's the upper level low! The long tail of clouds out ahead of the circulation that extends across far west Texas and Mexico is the Pacific Front, pretty cool, huh?



Current 500 millibar Wind Flow (winds around 18,500 feet above the surface, check out that giant dip across the western United States...that's the trough! Image below courtesy of Windyty.com >>> check it out HERE



Current Position of the Pacific Front:
>Breezy southerly winds here at the surface, and especially just above the surface will continue to advect, or more simply, transport, moist Gulf air into the area ahead of the approaching upper level trough and its associated surface frontal system. The Pacific Cold Front is currently moving through far west Texas. In their latest weather observation report, the El Paso International Airport is reporting a wind shift/frontal passage. Winds in El Paso are now gusting out of the west northwest over 25-40 mph with light rain falling and current temperatures in the mid 40s.

Tonight's Storm Threat:
>A line of strong, potentially severe thunderstorms is forecast to move through south central Texas late tonight into early Sunday morning as the upper level trough and Pacific Cold Front force the sticky, Gulf air mass to rise and precipitate. Meteorologists refer to lines of storms as "Squall Lines" and/or QLCS (Quasi-Linear Convective Systems). Squall lines are common in the spring, fall, and winter months in accordance with the presence of cold fronts.

Squall Line Forecast Position 3 A.M. Sunday Morning according to the NAM 4 km Model...this line of storms will stretch from Oklahoma City all the way down I-35 through Dallas, through Austin, through San Antonio to the Mexican Border

***The images below are a forecast model's simulation of what it thinks radar will look like at 3 am...use the images below to get a better idea of what radar MAY look like early Sunday morning...I can tell you, that this is not the only model forecasting this*** Remember, computer forecast models are just another tool in forecasting. 



Zoom In on Central Texas from the Image Above



The biggest threat with tonight's storms will be strong, gusty winds of 40-60 mph. The hail threat and the tornado threat are both low. In addition to the potential strong wind gusts, heavy rainfall and deadly cloud to ground lightning will accompany all thunderstorms. Due to the threat for potentially damaging thunderstorm wind gusts across the area tonight, the Storm Prediction Center out of Norman, Oklahoma has placed all of central Texas in the SLIGHT RISK CATEGORY (yellow-shaded area) for severe weather tonight.



The risk of flash flooding is LOW, due to the fast-moving, progressive nature of this storm system. We can expect to receive between 0.50 to 1.50 inches of rain out of this forecast rainfall event.

Sunday's Forecast:
Showers and thunderstorms will be well east of the area by mid to late Sunday morning as significantly drier and slightly cooler air moves into the area on the backside of this approaching upper level Pacific storm system. We will see plenty of sun and blue sky for your Sunday afternoon with temperatures mainly in the 60s. With a clear sky and dry air in place Sunday night, temperatures will drop into the 30s and 40s across the area, however, we will stay safely above freezing.

Strong Storms Possible Saturday

Forecast Discussion:
We officially topped out at 78°F this afternoon at Camp Mabry missing the record high of 81°F set back on this date in 1983. We've got a couple more well above average days tomorrow and Saturday ahead of Sunday morning's cold front that will help to knock high temperatures down closer to average for this time of year in the lower to middle 60s. That cooler air will come with a bit of price though on Saturday/Saturday night in the form of some thunderstorms.

>Some areas of fog will be possible across the area once again Friday morning. Please use caution when driving through fog and remember to use your low beam headlights.

>Record high in Austin on Friday is 83°F at Camp Mabry set back in 1950. Temperatures should easily manage the upper 70s to lower 80s across the area...we'll see a high near 80°F right here in Austin.

>Ahead of a deep trough of low pressure and upper level storm system that will be digging south across the western United States, Gulf of Mexico moisture will come flowing back up into the area at the lower levels of the atmosphere with Pacific moisture being brought into the area at the mid/upper levels of that atmosphere.

>This returning moisture will set the stage for showers and storms. As upper level disturbances and a Pacific Cold Front cross the area during the day on Saturday into early Sunday morning showers and thunderstorms look to become likely across the area.

>Some of the storms that develop Saturday afternoon, evening, and early Sunday morning have the potential to become strong or possibly even severe with strong, damaging winds being the primary threat along with locally heavy downpours and dangerous cloud to ground lightning (see more on this farther down)

>>>Moisture Return (Forecast look at wind direction and relative humidity around 18,500 feet aloft in the atmosphere around 9 a.m. Saturday morning...notice the blues and whites moving into Texas...that's Pacific moisture that will get pulled into this approaching storm system (given that there is a very limited amount of moisture that can exist at such high elevations, the Pacific moisture at this altitude helps to enhance the overall rainfall process, with the majority of the moisture with this next system coming from the Gulf of Mexico.



Saturday Storm Threat Timeline:

>>>Some areas of light to moderate rainfall possible with more widespread activity potentially developing towards the midday/early afternoon hours. We'll have to watch for the potential of a capping inversion over the area that may inhibit the amount of storms that are able to develop over the area during the morning hours.

>>>By afternoon, especially with the help of some breaks in the clouds, which helps to further destabilize our atmosphere, widely scattered to scattered showers and thunderstorms will be possible...majority of that activity should be along and east of the I-35 corridor...some heavier downpours with embedded lightning will be possible, strong wind gust and perhaps some small to medium sized hail cannot be ruled out. Remember, WHEN THUNDER ROARS, GO INDOORS!

>>>By late Saturday evening into early Sunday morning, a line of heavy showers and storms looks to approach the I-35 corridor from the west along the leading edge of the Pacific cold front...these storms will have the potential to bring strong gusty winds, heavy rain, and deadly cloud to ground lightning...activity should push well east of our area by midday Sunday, however, some leftover light rain showers will be possible early Sunday morning.

>>>Rainfall accumulation with this approaching storm system and frontal boundary looks to on average bring the area 0.50 to 0.75 inches of rain with higher totals possible along and east of the I-35 corridor and lower totals west. Some locations along and east of the Interstate 35 corridor could receive upwards of 1-2 inches of rain.

Forecast Rainfall Accumulation for the state of Texas according to the latest run of the NAM, or North American Forecast Model:

 

Saturday's Severe Weather Risk:
>>>The Storm Prediction Center has placed a large chunk of south central Texas in the SLIGHT RISK category for potential severe weather Saturday into early Sunday morning...area shaded in yellow below represents that SLIGHT RISK AREA...a slight risk for severe weather simply means there is a 15% chance at any one spot within that yellow shaded region of seeing severe weather (hail, high winds, tornadoes), although the tornado threat and hail threat does appear to be low. Obviously, it is important to remain weather aware when severe weather threatens.



***Please remember to heed all watches/warnings/advisories issued from the National Weather Service and its affiliates...please know and understand that this forecast may change slightly over the coming days so please stay tuned to the National Weather Service and your local weather for changing conditions***

Spring-like Weather ahead of Weekend Cold Front

Forecast Discussion:
We woke up to another chilly day across south central Texas with temperatures in the 30s and 40s area wide. Some patchy areas of fog developed thanks to the very efficient cooling that took place last night thanks to clear skies and dry air in place.

Well-above average Temps/Near Record Heat Possible
>>>Today (Tuesday) marks a warming trend for south central Texas that will take us into the first half of the weekend. Highs will easily manage to climb into the upper 70s to lower 80s by Thursday and Friday with a southwesterly component to the wind flow over the area at the lower levels of the atmosphere. Southwesterly wind flow for us here in central Texas is a warming wind because air is forced to compress as it moves from the higher elevations of northern Mexico into central Texas. Weak high pressure in place will allow for mostly sunny conditions to persist through Friday.

Forecast High Temperature Trend through Sunday
Data below for Camp Mabry, Austin, Texas




>>>A weak surface trough of lower pressure (or more simply a wind shift) will sneak into the area late tonight and shift winds to the west northwest allowing for some drier air to filter into the area. Some areas of fog may be able to develop ahead of this feature late tonight in some locations before drier air filters into the area. Overall, lows will be relatively WARMER tonight across the area in the 40s...upper 40s to near 50°F in Austin.

>>>As a large trough of low pressure digs south across the western United States on Thursday, surface pressures will fall to our north and allow for southerly winds to increase across the area which will effectively allow for Gulf of Mexico moisture to return to the area by Saturday ahead of our next cold front and upper level storm system. This trough of low pressure will track across the state of Texas Saturday and Sunday and give us a threat of storms as cooler air rushes into the state on its back side.

Saturday Storm Threat:
There is a chance for showers and storms with the front Saturday afternoon and evening, with some lingering activity possible into the morning hours on Sunday. The Storm Prediction Center is indicating is monitoring a good portion of central and east Texas for the possibility of some severe weather across the area on Saturday as the front moves through. Obviously, I will continue to keep a close eye on that through the week. As of right now, I feel like the best chance for storms, and appreciable rainfall will come east of the Austin area, however, latest forecast solutions indicate a 30-40% chance for storms Saturday afternoon/evening, some of which may be strong/severe with large hail and damaging wind gusts. Flooding does not look to be an issue with this weather system because of its forecast fast-moving/progressive nature. Rainfall will generally be less than a half an inch, if that. More east, less west.



Cooler Sunday:
Cooler air filters into the area behind the front late Saturday into Sunday on breezy northerly winds. This cold front will help to knock highs and lows closer to slightly below average for this time of year. Highs in the upper 50s to lower 60s with overnight lows in the lower 40s for Sunday/Sunday night...a few morning showers will be possible.

Next Week:
Quick warming trend ensues on Monday ahead of another, potentially stronger cold front by the middle of next week. Latest indications showing several blasts of cooler air arriving leading up to Christmas. I'll be keeping my fingers crossed for model consistency!

Sunshine Returns!

Forecast Discussion:
Good Tuesday afternoon everybody and welcome to December. Today is the first day of meteorological winter, the actual winter solstice will take place on December 22nd. After a dreary, wet, and roller-coaster temperature past seven days, a sunny, stable, and seasonably cool stretch of weather is in store for south central Texas.

Past Seven Days Temperature/Rainfall Trend (Austin/Camp Mabry):

HIGH/LOW/RAINFALL ACCUMULATION

*Average highs/lows for this time of year: 67/46

Tuesday (11/24): 64/47/0.00
Wednesday (11/25): 74/62/TRACE
Thanksgiving (11/26): 74/68/0.26
Friday (11/27): 74/41/1.46
Saturday (11/28): 44/39/0.25
Sunday (11/29): 47/42/0.04
Monday: (11/30): 55/45/0.00

Temperature/Rainfall Graph from the Past Seven Days Climate Data
(You can click on it to make it larger)

>>>The upper level low that brought us the clouds and the rain since last week is finally pushing east across the central plains today. As that upper level storm system moves east a dry cold front will be able to move through here tomorrow and effectively clear out our skies and allow high pressure to build in through the first half of the upcoming weekend. That means sunny, cool, and dry weather is in store for us with highs in the upper 50s to middle 60s with overnight lows in the 30s and 40s.

>>>Out-lying, low-lying locations within south central Texas may receive a light freeze Thursday and Friday mornings behind tomorrow's cold front. Temperatures will stay above freezing here in Austin.

>>>After tomorrow's cold frontal passage, our next cold front is set to arrive Sunday with a fast-moving upper level disturbance that may give us a few isolated sprinkles or very light rain showers across the area on Sunday. Other than that, Sunday's front will just work to reinforce the cool, dry air mass that will already be in place.

Looking ahead at the next three months, the Climate Prediction Center is continuing to call for below average temperatures across the southern United States and above average rainfall (typical of an El Niño winter). I have a feeling this is going to be an interesting winter for us, just as this past fall has been and continues to be!

Temperature Outlook (December, January, February)



Rainfall Outlook (December, January, February)