Winter weather advisories are in effect for northern sections of Garden State early Tuesday afternoon through early Wednesday morning.
The first of two storm systems that will be pestering New Jersey and Pennsylvania this week is already dropping light rain over southern and central counties Tuesday morning. But forecasters say the biggest threat is likely to come just in time for the evening commute.
That's when light snow could mix with sleet and freezing rain in northern counties, creating a thin layer of ice on some roads, bridges, sidewalks and parking lots.
"Periods of snow, sleet or freezing rain will cause travel difficulties," the National Weather Service said in a winter weather advisory posted for most of northern and western New Jersey. "Be prepared for slippery roads and limited visibilities, and use caution while driving," particularly north and west of the Interstate 95 corridor.
Winter weather explained
Salt trucks from the state Department of Transportation are already out patrolling state highways in northern and central New Jersey looking for any signs of slick conditions, said Dan Triana, an agency spokesman. In addition, warning messages are being posted on electronic message boards advising drivers to reduce their speed because of the expected winter weather conditions.
Here's a look at the advisories that have been issued by the weather service for specific regions, and the anticipated timing of the nasty weather:
WINTER WEATHER ADVISORY - BERGEN AREA
Region: This advisory affects western Bergen County, as well as Rockland and northern Westchester County in New York.
Winter weather advisories have been posted for areas shaded in purple. (National Weather Service)
Effective: 1 p.m. Tuesday to 9 a.m. Wednesday
Precipitation: Snow, sleet and freezing rain expected
Accumulation: Up to 1 inch of snow and a very thin coating of ice expected
Timing: Light snow expected to develop Tuesday afternoon, then mix with and change to sleet and freezing rain Tuesday night, then plain rain Wednesday morning.
Impact: Roads, especially those that are elevated or untreated, will become slippery, making travel hazardous, the weather service said. "This wintry mix will impact the Tuesday evening and Wednesday morning commutes."
WINTER WEATHER ADVISORY - MORRIS & WARREN AREA
Effective: 1 p.m. Tuesday to 6 a.m. Wednesday
Region: This advisory affects all of Morris County and Warren County, as well as Northampton County in Pennsylvania.
Precipitation: Snow, sleet and freezing rain expected
Accumulation: A coating to 1 inch of snow and sleet expected, along with a light glaze of ice
Timing: A period of snow is expected primarily Tuesday afternoon. It will mix with sleet before changing over to areas of freezing rain and rain late Tuesday afternoon and Tuesday evening, as temperatures hover around 30 degrees. Any lingering freezing rain Wednesday morning is expected to change to plain rain as temperatures rise.
Impact: "Untreated surfaces will become slippery due to some snowfall and then some icing," the weather service said. "Remember, bridges and other elevated surfaces tend to ice up first."
WINTER WEATHER ADVISORY - PASSAIC AREA
Region: This advisory affects western Passaic County, as well as Orange and Putnam counties in New York and northern Fairfield and northern New Haven counties in Connecticut.
Effective: 1 p.m. Tuesday to 9 a.m. Wednesday
Precipitation: Snow, sleet and freezing rain expected
Accumulation: Up to 1 inch of snow and a up to one-tenth of 1 inch of ice expected
Timing: Light snow expected to develop Tuesday afternoon, then mix with and change to sleet and freezing rain Tuesday night, then plain rain Wednesday morning.
Impact: Roads, especially those that are elevated or untreated, will become slippery, making travel hazardous, the weather service said. "This wintry mix will impact the Tuesday evening and Wednesday morning commutes."
WINTER WEATHER ADVISORY - SUSSEX AREA
Region: This advisory affects all of Sussex County, as well as Carbon and Monroe counties in Pennsylvania.
Effective: 1 p.m. Tuesday to 9 a.m. Wednesday
Precipitation: Snow, sleet and freezing rain expected
Accumulation: 1 to 2 inches of snow, and up to one-tenth of 1 inch of ice expected
Timing: A period of snow is expected primarily Tuesday afternoon. It will mix with sleet before changing over to areas of freezing rain Tuesday evening, as temperatures hover around 30 degrees. Any lingering freezing rain Wednesday morning is expected to change to plain rain as temperatures rise.
Impact: "Untreated surfaces will become slippery due to some snowfall and then some icing," the weather service said. "Remember, bridges and other elevated surfaces tend to ice up first."
The rest of New Jersey can expect plain rain, although some snow flakes could mix in at the start, forecasters said.
Then on Wednesday, a more intense storm system will be bringing batches of heavy rain, along with strong winds and the possibility of thunderstorms, to the entire state.
Len Melisurgo may be reached at LMelisurgo@njadvancemedia.com. Follow him on Twitter @LensReality. Find NJ.com on Facebook.