4th of July Weekend Forecast

Rest of Friday
    The rest of the daytime hours will be beautiful, with highs in the 80's and a mix of  clouds and sun.  Clouds will build through the rest of the day, as a low pressure system approaches the west and brings the threat for showers overnight tonight.

Saturday (4th of July!)
    As a low pressure system approaches the area and moves off just to the south, we'll see the threat for showers throughout the day tomorrow.  The best chance for precipitation looks to be during the morning and early afternoon, with chances for rain dwindling as you head into the evening hours.  Highs will likely remain in the upper-70's, with just enough humidity to feel a little uncomfortable but not bad.

This morning's NAM model run showing simulated radar at 11am tomorrow

Sunday
    High pressure builds back in and provides for plenty of sunshine and comfortable conditions.  Highs will jump back up into the mid-80's, making for a great end to the holiday weekend!

Tropical Storm Bill's Remnants to Bring Weekend Rain

    Tropical Storm Bill made landfall along Texas' Gulf Coast on Tuesday, June 16th, with winds to 60 mph and heavy rain.  Now, less than a week later, our area will be affected by the rainy remnants of that tropical cyclone.  Bill has certainly left its mark on the areas that it has passed through, bringing several inches of rain to portions of Texas and Oklahoma and severe weather (including tornadoes) to the Midwest.  Below is a radar loop of what Tropical Depression Bill looked like this evening over the Missouri/Illinois/Kentucky border area.

Tropical Depression Bill Radar Loop (Gif courtesy of RadarScope)

    So how will these tropical remnants affect our Father's Day Weekend in southern New Jersey?  Well, an unstable atmosphere will allow for scattered showers and thunderstorms to spark up across the region on Saturday during the daytime hours.  However, this is not the main concern.  Bill's area of low pressure will approach and push through Philadelphia and South Jersey late Saturday night and into Sunday morning.  The heaviest of the rainfall and storms look like they will fall after midnight and last into Sunday morning (likely out by 9am-12pm).  The image below shows this afternoon's NAM model run of the simulated radar at 8am on Sunday morning, showing heavy precipitation over the area.

18Z NAM model run's for Sunday morning at 8am (Image courtesy of Tropical Tidbits)

    The whole region is under a Flood Watch due to the potential for a long duration of heavy rainfall over a short amount of time.  Generally-speaking, it looks like we will be looking at upward of 1-3" of rain through overnight hours of Saturday/Sunday and Sunday morning.  Though, isolated locations could see 3"+ of rainfall, as the low pressure center brings a ball of very heavy precipitation into Southeast Pennsylvania and New Jersey. The image below shows a swath of heavy rainfall totals through Sunday evening from Kentucky to South Jersey.

Modeled precipitation totals through 8pm on Sunday evening (Image courtesy of the WPC)

    Finally, it does appear that when the rainfall ends Sunday morning, dry air will quickly pull in behind it to begin to dry things out.  Sunshine will likely make a return for the afternoon and evening (partly cloudy skies), but there will be the threat for scattered PM showers and storms as a low moves off to the north and a front moves through the area.

Rain and Storms Possible Through Tuesday Night

  It's looking like a rainy/stormy week ahead, with the threat of rain and storms possible each day.  This threat will especially be there for the next few days through Tuesday night (and again to end the week due to a tropical disturbance currently in the Gulf of Mexico).  Anyway, hot temperatures, humid air, and the chance for rain and storms (some have the chance of being severe) will be interspersed with periods more clouds than sun.  This weather is thanks to the set-up that will feature a warm front over the region through Tuesday evening, when a cold front will push through.

Today
  We'll see partly to mostly cloudy skies, with highs in the mid- to upper-80's.  Humidity levels won't be as bad as they will be in the coming days, and it'll be mainly dry throughout the afternoon and early evening.  Toward 7pm and later, we'll be looking at the threat for showers and storms, with periods of rain possible, especially after nightfall and overnight.  The severe threat won't really be there as much as tomorrow and Tuesday though.  The image below shows this morning's NAM model run simulating the radar for tonight at 11pm depicting moderate to heavy rain and storms over the area.

Above: This morning's NAM model run depicting the radar at 11pm tonight (Courtesy of Tropical Tidbits)

Tomorrow and Tuesday
  This will be the time period to really be on the lookout for thunderstorms and severe weather, as the atmosphere will have more instability.  Tomorrow will feature the chance for rain and storms throughout the day, and some storms could be severe, with the main threats being heavy rain and gusty winds.  Otherwise, dry periods will be under mostly cloudy skies, with highs around 90° and heat indices into the mid- to upper-90's (oppressive humidity).

  Tuesday will see much of the same, except with the threat beginning toward mid-day.  Though severe storms are more likely on Monday, the chance for them will remain for Tuesday, with periods of heavy rain and gusty winds being of main concern.  Highs will be 85-90°, with very oppressive humidity.  The cold front then pushes through during the evening.

Overview
  In general, it looks like most areas will be looking at upward of around 1" of rain through Tuesday; however, isolated areas could be looking at more under repeated downpours and storms, which is the norm during the spring and summer months.  The image below shows modeled rainfall totals through Wednesday at 8am and depicts upward of 1-3" across the area during that time frame.  Finally, threats for rainfall and storms will continue throughout the rest of the week, especially as moisture from what could be Tropical Storm Bill has the chance to affect the area toward the end of the work week.  However, tomorrow and Tuesday remain the best chances for severe thunderstorms.

Above: Modeled rainfall totals between today at 8am and Wednesday at 8am (Courtesy of NOAA)

Arthur Starting Off the 2014 Atlantic Hurricane Season This Week?

  The 2014 Atlantic Hurricane Season began on June 1st, but it has taken nearly a month for the first threat of a tropical system to really turn heads.  This week, we could be looking at our first named storm, which would be Arthur.  At this time, a cluster of showers and storms are meandering off the of the eastern coast of Southern Florida, associated with a weak low pressure center.  This system is slowly moving to the southwest at 5 mph but is likely to head northward over the coming days.

  Models are currently sticking to roughly the same trend, track-wise: bringing the system north-northwestward, hugging the coast.  The system then would make a possible landfall in North Carolina before tracking out to sea again and coming within a couple hundred miles off the coast of New Jersey.  Speaking about intensity, the system will be moving along the coast ahead of a trough, which is favorable for upward vertical motion of air and strengthening.  As of now, it appears that this system could become at least Tropical Storm Arthur before completely moving out to sea.

What does this mean for New Jersey?

  The combination of cold frontal boundaries passing through this week and a tropical system moving off the coast from the south will lead to a variety of wet and possibly severe weather.  First, as the cold front approaches from the west, we could be looking at the possibility of showers and storms, some of which could be severe, for Wednesday through Friday (slight chance for Tuesday).  Furthermore, the tropical system will add tropical moisture from the south to our area.  As it moves off the New Jersey Coast, though it will not make landfall, the possibility for strong wave activity, rip currents, and strong winds (especially along the immediate coast) is possible.  The possibility is there for this tropical system to cause issues from beach-goers for the Fourth of July and early parts of the weekend.

Below: Currently the most likely track for the tropical system

Last Arthur in the Atlantic Hurricane Basin

2008

Tropical Storm Arthur

Max Winds: 45mph, Minimum Pressure: 1004mb

Made landfall in Mexico

  

Updated Snow Map for March 16-17, 2014

I have updated my snow map to account for the likely shift in heavier precipitation toward the north.

Updated Snow Map

Late-Season Snowstorm Set to Clip New Jersey

    Another week and another storm…but this is déjà vu for forecasters, as this closely resembles the same situation that occurred with the storm in early March.  A low pressure system will push from west to east to the south of our region.  However, cold, dry air from the north will flow into our region and set up a sharp gradient between those who see snow and who don't. 

Timing

    Precipitation should enter the region Sunday night and last until Monday afternoon.  After that, scattered flurries/snow showers could linger throughout the Mid-Atlantic.  The further south you are, the more likely it is that you see a longer duration in snowfall.

Snowfall

    The dry air being ushered into our region has the chance to keep all accumulating snow south of Philadelphia.  Therefore, in the snow map that follows, I have first labeled an area, within the dashed lines, as ‘Area of highest uncertainty’.  I believe that the line between accumulating snow and non-accumulating snow showers/flurries will setup.  Then, the light blue swath is ‘T-2’, which represents an area where I believe that anything from flurries to 2” of snow may fall.  Finally, the ‘2-5’ swath is where I think the heaviest axis of snow will fall.  Also, warmer surface temperatures will likely affect how much snow actually sticks, but that is one of the challenges with forecasting in March.  In summary, the further south you go the better of a chance you have at accumulating snowfall.

Snowfall Map

Final Call for March 2nd/3rd Snowstorm

Overview

    Well, this storm has been extremely frustrating to forecast, and it looks like this will be the reversal of what we usually see in a Northeast/Mid-Atlantic snowstorm.  We’ll actually see snow totals increase as you head south, with the bulls-eye area ranging from Maryland into South Jersey.  Just 48-72 hours ago, the models agreed on a big snowfall over North/Central Jersey, but that has shifted well south, and that is why we have the predicted snow totals that we have today.

    

    Anyway, this storm is essentially moving from west to east, and a relatively narrow band of heavier snow will move through the region.  This band has been heavily influenced by the polar vortex over Canada, which has suppressed the biggest snowfall estimates to the south.  Therefore, we’ll likely see a sharp cutoff toward Central/North Jersey where areas see up to a half of a foot of snow and others see almost nothing.  Any change in storm track, no matter how small, from what is expected will alter snowfall totals.  In summary, the further north that you go, the less snow that you will see.  Behind this system, expect very cold temperatures, which has been the other story of this winter along with the high seasonal snowfall.

Timing

    The duration of this storm has greatly decreased for New Jersey, at least.  Scattered rain/snow showers this afternoon will move across the region, then the main bulk of the snow moves in this evening.  Snow will continue throughout the night and into the morning and begin to end from northwest to southeast.  The last of the snowfall will likely taper off by the afternoon hours of Monday.

Final Call Snowfall Map