...TERMINOLOGY USED IN NWS FORECASTS AND STATEMENTS...PART 3...

THE NATIONAL WEATHER SERVICE USES THE TERMS WATCH...WARNING AND
ADVISORY TO ALERT THE PUBLIC TO ADVERSE WEATHER CONDITIONS.

...WINTER STORM WATCH...
A WINTER STORM MAY AFFECT YOUR AREA. IT IS USED TO PROVIDE 24 TO 48
HOURS NOTICE OF A SEVERE WINTER WEATHER EVENT.

-THERE IS OFTEN UNCERTAINTY WITH THE PATH OR IMPACTS OF AN
UPCOMING STORM. A WINTER STORM WATCH IS UPGRADED TO A
WARNING WHEN THE NATURE AND LOCATION OF THE DEVELOPING
WEATHER EVENT BECOMES MORE APPARENT.

--------------------------------------------------------------------

THE FOLLOWING WARNINGS MAY BE ISSUED FOR SOUTH-CENTRAL AND
SOUTHEAST WISCONSIN...

...WINTER STORM WARNING...
SEVERE WINTER WEATHER IS OCCURRING OR IMMINENT. WINTER STORM
WARNINGS ARE USUALLY RESERVED FOR FORECASTS OF HEAVY SNOW EXCEEDING
6 INCHES IN 12 HOURS OR LESS. FREEZING RAIN OR SLEET MAY ALSO BE
MIXED IN WITH THE SNOW. A WINTER STORM WARNING COULD ALSO BE ISSUED
IF 8 INCHES OR MORE OF ACCUMULATIONS ARE EXPECTED IN A 24 HOUR
PERIOD.

-WARNINGS MAY ALSO BE ISSUED FOR LESSER AMOUNTS OF SNOW IF THE
BULK OF THE SNOW IS EXPECTED TO FALL DURING THE PEAK RUSH
HOUR PERIODS OR WITH STRONG WINDS OF 25 TO 34 MPH.

...BLIZZARD WARNING...
SUSTAINED WINDS OR FREQUENT GUSTS OF 35 MILES AN HOUR WILL OCCUR IN
COMBINATION WITH CONSIDERABLE FALLING AND/OR BLOWING SNOW FOR A
PERIOD OF AT LEAST 3 HOURS. VISIBILITIES WILL FREQUENTLY BE REDUCED
TO LESS THAN 1/4 MILE IN A BLIZZARD.

...LAKE-EFFECT SNOW WARNING...
RESERVED FOR FORECASTS OF LOCALIZED LAKE-INDUCED HEAVY SNOW SHOWERS
RESULTING IN ACCUMULATIONS EXCEEDING 6 INCHES IN 12 HOURS OR LESS...
OR 8 INCHES OR MORE IN A 24 HOUR PERIOD.

...ICE STORM WARNING...
RESERVED FOR FORECASTS OF FREEZING RAIN THAT LEAVE A COATING OF
ICE A QUARTER OF AN INCH THICK OR MORE IN 12 HOURS OR LESS.

...WIND CHILL WARNING...
LIFE-THREATENING WIND CHILLS REACHING MINUS 35 OR LOWER...IN
COMBINATION WITH SUSTAINED WINDS OF 4 MPH OR MORE.

--------------------------------------------------------------------

ADVISORIES ARE ISSUED FOR WEATHER CONDITIONS THAT ARE BELOW WARNING
CRITERIA WHICH WILL CAUSE INCONVENIENCES...BUT...IF CAUTION IS
EXERCISED...SHOULD NOT BE LIFE-THREATENING.

...WINTER WEATHER ADVISORY...

-A MIX OF SNOW...SLEET...FREEZING RAIN...OR FREEZING
DRIZZLE. THIS IS THE MOST COMMON TYPE OF ADVISORY ISSUED
SINCE MULTIPLE TYPES OF PRECIPITATION OFTEN OCCUR WITHIN ANY
SINGLE EVENT.

-SNOW ACCUMULATIONS OF 3 TO 6 INCHES IN 12 HOURS OR LESS..WITH
WINDS LESS THAN 25 MPH.

-ADVISORIES CAN BE ISSUED FOR SNOW ACCUMULATIONS LESS THAN 3
INCHES IF THE BULK OF THE SNOWFALL IS EXPECTED DURING
PEAK RUSH HOUR PERIODS...AND ROADS ARE EXPECTED TO BECOME
VERY ICY.

-JUST SLEET ACCUMULATIONS...WITH ACCUMULATIONS OF 1/2 INCH TO LESS
THAN 2 INCHES.

-SNOW AND BLOWING SNOW CONDITIONS WITH VISIBILITIES OCCASIONALLY
1/4 MILE OR LESS FOR 3 HOURS OR MORE.

...LAKE-EFFECT SNOW ADVISORY...
LAKE-EFFECT SNOW EVENT IN WHICH LAKE-INDUCED SNOW SQUALLS OR HEAVY
SNOW SHOWERS RESULT IN SNOW ACCUMULATIONS OF 3 TO 6 INCHES.

-ADVISORIES CAN BE ISSUED FOR SNOW ACCUMULATIONS LESS THAN
3 INCHES IF THE BULK OF THE SNOWFALL IS EXPECTED DURING PEAK
RUSH HOUR PERIODS...AND ROADS ARE EXPECTED TO BECOME VERY ICY.

...FREEZING RAIN ADVISORY...
LIGHT FREEZING RAIN AND/OR FREEZING DRIZZLE WITH ICE ACCUMULATIONS OF
LESS THAN 1/4 INCH IN 12 HOURS OR LESS.

...WIND CHILL ADVISORY...
WIND CHILLS BETWEEN -20F AND -34F FOR 3 HOURS OR MORE WITH
SUSTAINED WINDS OF 4 MPH OR MORE.

...DENSE FOG ADVISORY...
ISSUED YEAR-ROUND FOR FORECASTS OF DENSE FOG THAT REDUCE VISIBILITIES
TO 1/4 MILE OR LESS FOR AT LEAST 3 HOURS.

-----------------------------------------------------------------
FOR MORE INFORMATION ON WINTER WEATHER...VISIT...

http://www.nws.noaa.gov/om/winter/    

http://www.crh.noaa.gov/mkx/?n=winter-wx-awareness

 

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.