Discussion: Nothing noteworthy in the upper levels for this weekend. The main player will be an area of high pressure slowly tracking from Ohio, over the N Mid-Atlantic US, and out into the Atlantic Ocean. It’s a good time to revisit the physics of high pressure. In the N Hemisphere it’s an anti-cyclone with air moving clockwise around it’s center. These kind of highs move generally from W to E (at different angles) across the US with the mid-latitude westerlies. When the high initially approaches NJ from the W, we see colder and drier N flow. When it’s directly over NJ, we see very calm and tranquil conditions. When it gets out into the Atlantic, we see S flow from it’s back-side (aka return flow). Today (Friday), it’s approaching. Tomorrow (Saturday) it will be overhead. Sunday it will be departing. Normally high pressure represents dry conditions synoptically (larger organized precip systems stay away). But at mesoscale level, we’ll seeing warmer surface temperatures under a cooler air mass aloft. Since heat rises, this puts isolated instability-driven showers and even thunderstorms on the table. The best chance for this to happen is during afternoon hours (during peak diurnal surface heating). Again, this is a small possibility and likely very isolated given the larger-scale sinking dry air associated with the high. Otherwise this weekend looks quite pleasant. Mild days and cool nights. Next week it looks like another area of high pressure could keep us mild/warm and mostly dry.
Friday (May 14) high temperatures should break 70 for many. ECNJ/SENJ coastal areas have a better chance to hang in the upper-60s/near-70. WCNJ/SWNJ has a better chance to run towards 80. A gorgeous day for all given lower humidity. Skies should be mostly sunny. Winds should be light out of the NW. Overnight lows should range from mid-40s to mid-50s from elevations to coasts.
Saturday (May 15) high temperatures should have a similar profile to Friday, maybe a few degrees warmer. The transition from low humidity to normal humidity might make it feel a little warmer as well. Skies should be mixed with sun and clouds (sunnier to start the morning) with afternoon showers possible. Winds should be near-stationary (a few mph in any direction). Overnight lows should range from upper-40s to upper-50s from elevations to coasts
Sunday (May 16) high temperatures should reach near-70 for most areas. Skies should be mixed with sun and clouds. Can’t rule out an isolated shower. Winds should be light out of the SW. Overnight lows should range from mid-40s to mid-50s from elevations to coasts.
An early look at next week indicates 70+ high temperatures sustaining with typical warmer spots (interior CNJ/SNJ) likely heading into 80s midweek. No major rain or storm systems detected as of now, mostly dry conditions, but isolated spring showers (even thunderstorms) can pop up randomly this time of year.