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Do you have a weather question? Ask one of the News 8 Austin meteorologists. You can send an e-mail to them through our feedback form.
Be sure to read the Storm Safety tips so you will be prepared in case of severe weather.
A watch alerts you to potential severe weather approaching your area. It doesn't mean the severe weather will occur. It means you should prepare for the weather to worsen.
A warning states the severe weather is impending or present in your vicinity. You should immediately take precautions to protect yourself and your family. Be sure to read the News 8 Storm Safety guide for advice on what to do when severe weather strikes the Austin area.
News 8 Austin's "Weather on the Eights" is one of the best ways to receive watches, warnings and advisories from the National Weather Service. Be sure to tune in during alerts for up to the minute, live forecasts of the weather in your area.
BLIZZARD WARNING
Is issued for a combination of strong winds with frequent gusts of 35 mph and greater along with very low visibility due to blowing or falling snow.
BLIZZARD WATCH
Is issued in advance for the potential of very strong gusty winds of 35 mph or greater combined with blowing or falling snow.
BLOWING SNOW ADVISORY
Is issued when the visibility will be significantly reduced or when the roads become snow covered over a large area.
DENSE FOG ADVISORY
Is issued when widespread fog is expected to reduce visibilities to 1/4 mile or less for more than three hours.
FIRE WEATHER WATCH
Issued to advise a given area of possible Red Flag conditions during the next 12-72 hours
FLASH FLOOD/FLOOD WARNING
Is issued when flooding is being reported or is imminent. Take necessary precautions at once. You may only have seconds!
FLASH FLOOD/FLOOD WATCH
Is issued when flooding is possible within the designated area. It is issued in advance to give people the time to move property and livestock to higher ground. Be alert!
FLOOD ADVISORY
Is issued by the National Weather Service when there is a potential for periods of heavy causing flood problems. An ADVISORY
Will be issued well in advance of the flood threat.
FOG ADVISORY
Is issued when fog will reduce visibility significantly causing potential travel hazards.
FREEZE ADVISORY
Is issued when there is a potential in the next few days of the temperatures dropping to below 32 degrees. It is issued to give people time to take necessary precautions.
FREEZE WARNING
Is issued when the temperature is expected to fall below 32 degrees for three hours or greater. The WARNING is issued in advance of the freeze in order to give people time to protect tender vegetation, pipes and other exposed objects.
FREEZING DRIZZLE ADVISORY
Is issued in advance for the potential of freezing drizzle causing an accumulation of ice on exposed surfaces, including roads, power lines and trees. Freezing Drizzle is drizzle that freezes upon impact because the air temperature is below 32 degrees.
FREEZING RAIN ADVISORY
Is issued in advance for the potential of freezing rain causing an accumulation of ice on exposed surfaces, including roads, power lines and trees. Freezing Rain is rain that freezes upon impact because the air temperature is below 32 degrees.
FROST ADVISORY
Will be issued when the potential of high humidity and falling temperatures below 32 degrees leaves a thin coat of ice on exposed surfaces.
FROST WARNING
Is issued when the formation of frost, or a thin layer of ice crystals, will coat surfaces. Frost develops similar to dew when the temperature falls below 32 degrees.
FROST/FREEZE ADVISORY
Is issued for the potential of temeratures falling below 32 degrees and the humidity being high enough to create a thin layer of ice or ice crystals on exposed surfaces.
HEAT ADVISORY
Is issued between May 1 and June 30 when the Heat Index, a combination of the air temperature and the humidity, is forecast to be 98 to 105 degrees for one day or longer. It is issued between July 1 and September 30 when the heat index is forecast to be 100 to 110 degrees for one day or longer.
HEAT WARNING
Is issued by the National Weather Service when the Heat Index, a combination of the actual air temperature and humidity is expected to exceed 115 degrees during any length of time during the day.
HEAVY SNOW WARNING
Is issued for snowfall of between four and seven inches in a 24-hour period.
HEAVY SNOW WATCH
Will be issued when the potential exists for snowfall of between four and seven inches in a 24-hour period. This WATCH will be issued at least 12 hours in advance of potentially heavy snow.
HIGH WIND ADVISORY
Is issued when the weather service feels there is a threat in the next few days of possible sustained winds of 40 mph or greater and/or sustained gusts of 57 mph or greater.
HIGH WIND WARNING
Is issued when winds will average 35 to 40 mph or greater and/or wind gusts will be greater than 57 mph or greater for one hour.
HIGH WIND WATCH
Is issued in advance of possible sustained winds of 40 mph or greater and/or gusts of 57 mph or greater. The WATCH may be issued up to 12 hours in advance of these wind speeds.
ICE STORM WARNING
Is issued when freezing rain or freezing drizzle will leave accumulated ice on roadways, power lines, trees and other exposed objects.
LAKE EFFECT SNOW ADVISORY
Will be issued when there is a potential for lake effect snowfall accumulation to seven inches or more within a 12-hour period.
LAKE EFFECT SNOW WARNING
Is issued when heavy lake effect snow is occurring or is approaching, or has the probability of occurring in the next 12 hours. Snow accumulations of seven inches along with strong winds will be the main effects.
LAKE EFFECT SNOW WATCH
Is issued for the possibility of heavy lake effect snow accumulation to seven inches or greater. This WATCH will be issued at least 12 hours in advance of potentially heavy snow accumulations.
RED FLAG WARNING
A critical combination of dry (low humidity, low soil moisture) and windy weather conditions that presents a significant and imminent high to extreme fire danger in a given county. Typical conditions include winds greater than 15 mph, relative humidity around or less than 25%, and temperatures generally greater than 75 degrees. Thunderstorms with dry lightning also prompt this warning. May be issued when confidence is high Red Flag conditions will occur within the next 24 hours.
RIVER FLOOD WARNING
Is issued when flooding is occurring or is imminent at one or more forecast points along a river.
SEVERE THUNDERSTORM WARNING
Is issued when severe thunderstorms are occurring or about to move in to the area. Get to a safe place immediately.
SEVERE THUNDERSTORM WATCH
Is issued when thunderstorms produce any and all of the following weather features: Hail 3/4" in diamter or larger, wind gusts to 58 mph or greater and/or tornadoes.
Thunderstorms producing the following may occur in your area:
- Hail ¾" in diameter or larger, wind gusts 58 mph or greater and/or tornadoes.
- Wind gusts 58 mph or greater and/or tornadoes.
- Frequent lightning and flash flooding may also accompany severe thunderstorms.
SNOW ADVISORY
Is issued when the National Weather Service feel that a certain area may receive significant accumulations over a 12-hour period.
TORNADO WARNING
Is issued when a tornado has been sighted or indicated by weather radar and/or the Skywarn spotter network. Tornado Warnings are issued by the National Weather Service. When a Tornado Warning is issued where you live you should get to a safe place immediately.
| Fujita Wind Damage Scale |
| F0: | Up to 72 mph | Light Damage |
| F1: | 73 - 112 mph | Moderate |
| F2: | 113 - 157 mp | Considerable |
| F3: | 15 - 206 mph | Severe |
| F4: | 207 - 260 mph | Devastating |
| F5: | Above 261 | Incredible |
TORNADO WATCH
Is issued in advance of possible tornadoes and severe thunderstorms. Continue with your normal routine but remain alert for approaching storms.
URBAN SMALL STREAM FLOOD ADVISORY
Is issued when local flooding of small streams, streets or low-lying areas such as railroad underpasses is occurring or imminent.
WIND ADVISORY
Is issued when there is a potential of sustained winds of 25 to 39 mph and or sustained gusts of 40 to 56 mph during a given time period.
WIND CHILL ADVISORY
Is issued when the combination of cold temperatures and wind is computed to be -25 degrees or less for at least three hours.
WIND CHILL WARNING
Is issued when winds will combine with cold temperatures to create dangerously cold conditions for exposed skin. Frostbite and hypothermia can occur. Limit time outdoors. When you do go, dress in layers and cover all exposed skin.
WINTER STORM ADVISORY
Will be issued by the National Weather Service when there is a possibility that some type of winter weather will occur in the next few days. The weather types would be snow, sleet and/or freezing rain or freezing drizzle.
WINTER STORM WARNING
Is issued when the threat for snow of seven inches or greater in a 24-hour period OR accumulations of ice due to freezing rain or freezing drizzle will down trees and powerlines.
WINTER STORM WATCH
Is issued when there is a threat of winter weather due to heavy snow, sleet or ice accumulations on trees and power lines. The WATCH is issued at least 12 hours in advance of possible severe winter weather.
WINTER WEATHER ADVISORY
Is issued for a combination of of snow, sleet and/or freezing rain. The ADVISORY is issued in advance of a possible winter weather event that will cause roads to become slippery and to alert motorists that travel is not recommended.
The average sky cover is part of our daily forecast. This percentage is the amount of sky expected to be covered by opaque clouds, the type that do not allow other clouds, or blue sky to be visible. The following table lists descriptive terms for sky conditions:
| TERMINOLOGY |
|
AVERAGE SKY COVER |
|
| Cloudy |
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90-100 percent |
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| Mostly cloudy |
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70-80 percent |
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| Partly Cloudy/Partly Sunny |
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30-60 percent |
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| Mostly Clear/Mostly Sunny |
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10-30 percent |
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| Clear/Sunny |
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0-10 percent |
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| Fair |
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Few clouds and no precipitation or extreme weather |
The forecast for the probability of precipitation is one of the least understood elements of forecasting. The probability of precipitation has the following features:
| - |
|
The likelihood of precipitation is stated as a percentage |
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| - |
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A measurable amount is defined as 0.01" (one hundredth of an inch) or more. More than 0.01" usually produces enough runoff for puddles to form |
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| - |
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The measurement is of liquid precipitation or the water equivalent of frozen precipitation |
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| - |
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The probability is for a specified time period |
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| - |
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The probability forecast is for any point in the forecast area |
Let's look at an example
If a forecast for a given Travis County says there is a 40 percent chance of rain this afternoon, then there is a 40 percent chance of that it may rain anywhere in Travis County from noon to 6 p.m.
The probability of precipitation is determined by the forecaster by multiplying two factors: Forecaster certainty that precipitation will form multiplied by the anticipated percentage of the area that would be receive precipitation.
Here are two examples giving the same result
If the forecaster was 80 percent certain that rain would develop but only expected to cover 50 percent of the forecast area, then the forecast would be "a 40 percent chance of rain" for any given location.
If the forecaster expected a widespread area of precipitation with 100 percent coverage to approach but was only 40 percent certain that it would reach the forecast area, this would result in a "40 percent chance of rain" at any given location in the forecast area.
The following terms of duration imply a high probability (80 to 100 percent) of occurrence: brief, periods of, occasional, intermittent, frequent.
Terms of uncertainty are listed:
| PROBABILITY OF PRECIPITATION |
|
TERMS USED |
|
| 0 percent |
|
None |
|
| 10 percent |
|
Slight Chance, Isolated |
|
| 20 percent |
|
Slight Chance |
|
| 30-50 percent |
|
Chance, Scattered |
|
| 60-70 percent |
|
Likely, Numerous |
|
| 80-100 percent |
|
Categorical ("Rain this afternoon") |
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New Moon
When the Moon is not illuminated by direct sunlight.
Waxing Crescent
Occurs when the visible Moon is partly but less than one-half illuminated
by direct sunlight while the illuminated part is increasing.
First Quarter
When one-half of the Moon appears illuminated by direct sunlight while the
illuminated part is increasing.
Waxing Gibbous
When the Moon is more than one-half but not fully illuminated by direct
sunlight while the illuminated part is increasing.
Full Moon
When the visible Moon is fully illuminated by direct sunlight.
Waning Gibbous
The Moon is less than fully but more than one-half illuminated by direct
sunlight while the illuminated part is decreasing.
Last Quarter
Is when one-half of the Moon appears illuminated by direct sunlight while
the illuminated part is decreasing.
Waning Crescent
Occurs when the Moon is partly but less than one-half illuminated by
direct sunlight while the illuminated part is decreasing.
Atmosphere
The envelope of gases surround the surface of the planet
Atmospheric models
Simulation of the atmosphere's behavior by mathematical equations or by physical models
Ceiling
The height of the lowest layer of clouds
Climate
The accumulation of daily and seasonal weather events over a long period of time
Cold Front
The leading edge of a cold air mass advancing onto a warm air mass
Dew Point
The temperature to which air must be cooled to in order for dew (or frost) to form
El Niño
An extensive warming that begins along the coast of Peru and Ecuador; occurs once every 3 to 7 years
Fog
A cloud with its base at the Earth's surface
Heat Index
An index that combines the air temperature and relative humidity to determine an apparent temperature - how it really feels
High
A region of air with higher-than-normal barometric pressure, around which winds blow clockwise. Usually associated with fair weather
Jet Stream
Strong winds at about 35,000 feet that divide air of different temperatures, and act as steering currents for weather systems
La Niña
A condition where the central and eastern tropical Pacific Ocean waters turn cooler than normal
Low
A region of air with lower-than-normal barometric pressure, around which winds blow counter-clockwise. Usually associated with stormy weather
Meteorology
The study of the atmosphere and atmospheric phenomena as well as the atmosphere's interaction with the Earth's surface, oceans and life in general
NEXRAD
An acronym for Next Generation Weather Radar. The main component of NEXRAD is Doppler radar
Precipitation
Any form of water particles - liquid or solid - that falls from the atmosphere and reaches the ground
Relative Humidity
The ratio of the amount of water vapor in the air compared to the amount of water vapor the air (at a certain temperature) can hold
Stationary Front
A boundary separating two air masses that shows little or no movement
Warm Front
The leading edge of a warm air mass advancing onto a cold air mass
Weather
The condition of the atmosphere at any particular time and place
Wind Chill
The cooling effect of any combination of temperature and wind, expressed as the loss of body heat
Allergies: Mountain Cedar Forecasts
Air Quality Report
Austin Ozone Forecast
International Space Station … see it from your backyard!
Sun & Moon Rise/Set chart
Moon Phase Calendar
Weekly Stargazing Tips
Lower Colorado River Authority
Texas Drought Monitor
Outdoor Burning Bans
Austin Road Closures
Texas Road Conditions
Be sure to read the Storm Safety tips so you will be prepared in case of severe weather.
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