Saturday will be a spectacular weather day. Sunday, however, is a very different story.

Background map: NAM model precipitation forecast as of Sunday evening. (College of DuPage Meteorology)

This final weekend of October is going to end with a bang, as heavy rain and gusty winds collide with New Jersey. Such nasty weather almost seems an appropriate way to commemorate the 5-year anniversary of Superstorm Sandy's landfall on New Jersey — October 29, 2012.

I think it's important to note that this is a complicated, but pretty nasty weather setup. Big rain and big wind are in the forecast. But as long as you play it smart, this storm shouldn't pose a significant danger to your life, family, or property. (In other words, it is not a "bread and milk" storm, and any comparison to Sandy's impacts is total hype.)

1.) Spectacular Saturday

Don't let Sunday's active weather forecast affect your Saturday plans — it's going to be a beautiful day! Morning temperatures are mostly in the 40s, and thermometers will make a run for 70 degrees later on. Sunshine will dominate the sky for the first half of the day.

However, look for clouds to start increasing Saturday afternoon. And it will become noticeably breezy as well, up to 15 or 20 mph.

Our weather will stay dry until at least sunset Saturday (and probably through Saturday evening too). So there's no meteorological excuse to enjoy the pleasant Fall weather!

2.) Sunday's Stormy Setup

A combination of storm systems will push our weather downhill throughout the day on Sunday. And Monday too.

The first piece of this stormy puzzle is a cold front, racing toward New Jersey from the west. Remember a front is defined as the leading edge of cooler, drier air. The difference in density between our current air mass and our approaching air mass causes lift to occur. When lift occurs in the atmosphere, we get clouds and rain.

Forecast update for Potential Tropical Cyclone 18, as of 8 a.m. Saturday. (NOAA / NHC)

The second important aspect of this forecast is Potential Tropical Cyclone 18, which will probably become Philippe in the coming days. The storm will make landfall over southwestern Cuba on Saturday, before tracking across the southern tip of Florida and the Bahamas by early Sunday morning. PTC 18 is not an incredibly strong or organized storm, not expected to intensify to hurricane strength. And the consensus storm track keeps the center of the storm east of New Jersey. (Note: that's not a sure bet, just playing the probabilities.)

However, what's important here is the incredible amount of moisture that 18/Philippe will carry from the Caribbean into the atmosphere over the western Atlantic Ocean. As this tropical disturbance "phases" (or "merges") with the aforementioned cold front, that tropical moisture will be carried into our neighborhood. That moisture will fuel some very heavy rainfall in the region. And the remnant low will encourage some strong winds too.

3.) Timeline

GFS model precipitaton forecast for 5 p.m. Sunday, as the axis of heaviest rain swings through the Garden State. (College of DuPage Meteorology)

As I already mentioned, first raindrops aren't expected until Saturday evening at the earliest. More likely, the arrival of showers will hold off until around daybreak Sunday.

Widely scattered showers will quickly transition to a period of steadier rain, likely in the mid to late morning hours on Sunday.

The heaviest rain will push through New Jersey from mid-afternoon Sunday through the evening time.

Rainfall will taper to showers by Midnight, with residual raindrops possible through mid-morning Monday.

4.) Wind

Meteogram of forecast wind speeds/gusts for Trenton. Note the peak occurs early Monday morning. (Iowa State Meteogram Generator)

My biggest concern regarding this stormy setup is actually not the rain, but the wind. (That's pretty astonishing given the impressive rainfall totals I'll discuss momentarily.)

An extended period of elevated winds is forecast for Sunday and Monday, given the tight pressure gradient over the Northeast U.S. Sustained winds of 15 to 25 mph will initially blow from the southeast, transitioning to a westerly direction on Monday.

Peak winds will actually happen after the direction switch, early Monday morning. (Yes, you read that right — the biggest wind will come after the heaviest rain, making for a blustery Monday morning commute.) Gusts in the 40 to 50 mph range are a reasonable exception, especially along the eastern edge of NJ. (FYI, the National Weather Service has hinted at a High Wind Watch or Wind Advisory at some point.)

Such winds are certainly strong enough to turn your garbage cans, patio furniture, and Halloween decorations into projectiles. Sporadic power outages due to downed trees and lines are possible too.

Some have hypothesized that "hurricane-strength gusts" will be possible. That's 74 mph — I don't buy it. (Maybe well off-shore, but not over land.)

5.) Rain

NAM model rainfall totals forecast for Sunday and Monday. While the NAM tends to overestimate rainfall, localized 3+ inches is a good possibility. (College of DuPage Meteorology)

Model rainfall totals for New Jersey run the gamut from 0.5" to 5". There's still some uncertainty regarding the exact track of the heaviest rain, but I think we'll mostly end up in the middle of that range.

The lightest rain and lowest totals will be found in southwestern New Jersey (say the I-295 corridor). In that area, I expect 1 to 2 inches to fall.

Most of the state should see rainfall of about 1.5 to 3 inches. That's a fairly big range of possibilities, but the impacts are the same — wet, wet, wet.

We might find a few localized areas of 3+ inches of rain along the coast and to the north. It all depends on where the heaviest rain bands form, and how slowly they move.

A Flash Flood Watch has been issued for 8 counties in northern NJ for Sunday. (NOAA / NWS)

The potential for widespread flooding will be fairly limited, given our dry ground. (That's called the "antecedent condition".) Still, if 3+ inches of rain falls, even the driest ground and emptiest storm drains could become inundated. Following the technical flash flood guidance numbers, the National Weather Service has issued a Flash Flood Watch for northern New Jersey: Bergen, Essex, Hudson, Morris, Passaic, Sussex, Union, and Warren counties.

Overall, it amounts to some solid, healthy rainfall for all of the Garden State. According to the latest U.S. Drought Monitor, about 54 percent of New Jersey is classified as "Abnormally Dry" (D0) — that's the northern and western parts of the state.

6.) Coastal Issues

ET-SURGE model, showing just a foot or two of surge along the Jersey Shore, peaking around the Raritan Bay. (NOAA / OPC)

A big storm in the ocean usually leads to a big push of water toward the Jersey Shore. And there will be some bigger waves — I see 3 to 6 foot waves hitting the beaches, with 6 to 10 foot waves just off-shore. This surf forecast is highly dependent on the exact track of the storm, but I like what I see in terms of mitigating the chance of "major" beach erosion.

Meanwhile, the coastal flooding picture looks good too. The predominant southeast and west winds are great wind directions for avoiding surge. A foot or two of storm surge could push water levels into the minor flood category in a few spots (mainly Monmouth County beaches). The most precarious high tide cycle will be Sunday afternoon. But again, I'm happy to say we should avoid any big water inundation issues.

7.) What's Ahead

GFS model temperature forecast for Monday afternoon, limiting highs to the 50s across New Jersey. (College of DuPage Meteorology)

Behind Sunday's rain and Monday's wind, a burst of cooler air will settle over New Jersey. Monday's high temperatures will be limited to the mid to upper 50s. Your Halloween forecast includes sunny skies and quiet weather, but we'll stay on the cool side with below-normal highs again in the 50s. Nighttime low temperatures will probably end up around 40 degrees for the first half of next week.

However, this cooldown is pretty shallow — far from "wintry" conditions. And it will be temporary. A warm front slides through New Jersey late Wednesday, delivering our next chance of showers. And, as the name suggests, behind the front will come a warmup. Thermometers will once again race toward 70 degrees by the end of the workweek.