Another Day of Heat, Humidity, and Poor Air Quality for NJ
While Thursday will see near-record high temperatures once again, this Garden State heat streak will break by the upcoming weekend.
Here are your weather headlines for Thursday, May 18, 2017...
Thursday: Another Hot Day
The sweating continues! We hit a record high at Trenton on Wednesday, and ended up just a few degrees shy at Newark and Atlantic City. The hot, humid air returns to the Garden State on Thursday, and temperatures may actually end up a degree or two warmer.
A brisk southwest wind will keep the hot air on top of the Garden State, a process known as "warm air advection". Forecast high temperatures for Thursday range from 88 to 95 degrees. The record high at Newark Airport in particular will be in jeopardy: the current record is 90 from 1986, and our forecast calls for 93.
The NJ DEP has once again issued an Air Quality Alert as Thursday's heat and humidity will lead to elevated levels of ground-level ozone and particulates. Combined with the high pollen level, that could make breathing difficult for sensitive groups: the very young, the very old, and those with respiratory problems. If you fall into one of those categories, you'll want to limit your time outdoors during the hottest part of the day.
Unlike Wednesday, Thursday will bring scattered clouds overhead, so at least the sun won't be beating down all day.
You'll find some relief from the heat at the Jersey Shore, with slightly cooler temperatures at the beach. This is especially true on the barrier islands, as the sea breeze and cool bay temperatures combine to mitigate the effects of that hot furnace-like southwesterly breeze.
Thursday night will remain muggy and partly cloudy, with lows only falling to around 70 degrees. A storm system may provide a glancing blow to North Jersey, with a slight chance for a brief shower or thunderstorm Thursday evening (between about 7 p.m. and 11 p.m.)
Friday: Starts Warm
The first half of Friday (at least) will be just like Wednesday and Thursday. Thermometers will cook to the mid to upper 80s by midday. Starting in the afternoon hours, however, we'll be tracking a cold front that will spell the end of this streak of hot weather.
Usually when I reference a "front," the same sentence includes a chance of rain. While there will be a chance for showers and thunderstorms on Friday afternoon — mainly in South Jersey — the rain chance honestly looks pretty minimal. The most significant weather impact will be an influx of cooler, drier air. You will immediately notice the drop in humidity, alongside a slow decline in temperatures through the weekend.
The 80s and 90s will be long gone by the weekend. Forecast highs for Saturday are in the upper 60s for most of New Jersey. The coast will be particularly cool, only in the lower 60s.
But this cooldown is not necessarily bad news! 60s are just a little bit below normal highs for mid-May (lower 70s). Skies will probably range from mostly to partly sunny on Saturday, and we should stay dry.
Clouds will increase on Sunday, with similar temperatures in the mid to upper 60s. We might break 70 degrees in SW NJ, while the coast remains on the cool side thanks to an ocean wind.
Our Next Big Storm System
Monday will start with a warm front, switching winds to blow from a southerly direction. That will be a warming wind, pushing temperatures to the lower to mid 70s for most of the state. (If that warm front doesn't make it all the way through the entire state, North Jersey may remain much cooler in the 60s.)
The ensuing cold front for Monday afternoon looks to be a doozy. Models depict a round of strong thunderstorms from about mid-afternoon Monday through late evening. A period of heavy rain may be accompanied by loud thunder and some gusty winds. This one is worth watching if you have outdoor plans late Monday.