Showers tomorrow, upper 70s Saturday, heavy rain on Monday

Finally, we’ve had some consistent signs of Spring.

1) We’ve posted our “Winter 2014-2015 in Review” article instead of constantly talking about the next snow event.

2) On Wednesday, NYC had its first 70+ degree day (a high of 72) since October 29, 2014, when they also hit 72 degrees.

3) Upper 70s are likely on Saturday.

Today is a bit colder than it was yesterday due to a High Pressure system sliding offshore, and providing winds from the cold ocean. As this High Pressure continues to slide away from us, it will temporarily lose control over our weather, and instead a wave of energy along a front will be moving in late tonight and during the day tomorrow.

Clouds will increase tonight and temperatures will drop to around 50 degrees. Showers may move into the region sometime after 4:00am. This is not expected to be a heavy rain event, as the forcing for precipitation looks weak and the atmosphere will remain stable. Still, though, a few patches of light to moderate rain appear likely from shortly before sunrise, through mid-morning.

The front will be slow to move out of the area, so cloudy skies and a few patchy showers could remain for the rest of the day, but we are not expecting much rain at all. This means that baseball will very likely be played in Citi Field on Friday night.

By Friday night, the front will have completely cleared the area. It’s a weak front, so temperatures will not be cooling off much at all, and with sunshine and dry downsloping winds returning, Saturday looks to be quite the warm, sunny day.

Today's NAM model valid for Saturday afternoon shows widespread 70s for highs.

Today’s NAM model valid for Saturday afternoon shows widespread 70s for highs.

Verbatim, the NAM is showing highs generally in the low 70s, though cooler on the east end of Long Island, where the winds abruptly turn to SW. But with a strong NW flow and 850mb temperatures of around +8C, we actually think the low 70s the NAM is showing is the floor for high temperatures on Saturday. With how dry it’s been and will continue to be on Saturday, the NW flow assures that we will be mixing deeply with this warm airmass, keep clouds away, and should maximize our potential warmth. This means that upper 70s for most of the area are likely, and we can’t even rule out an isolated warm spot hitting 80 degrees! Definitely make sure to get outside and enjoy it.

Moving forward to Sunday, it actually looks quite similar to today’s weather. The high pressure system behind the front on Saturday will be moving offshore, so winds will take a bit more of an offshore turn — thus ushering in cooler temperatures from the ocean. That being said, the airmass will be a bit warmer on Sunday than it is today, so widespread low to mid 60s still appear likely, assuming we can hold clouds off. As of now, it looks like a partly cloudy day, so the weekend as a whole looks to be quite nice.

Unfortunately, that will all take a bad turn starting on Monday. The high pressure system will completely lose its grip on the area, as a hemispheric pattern change will be unfolding. A large cutoff low that is currently producing severe weather in the Southern Plains will slowly drift eastward and weaken, while a strong ridge will be developing in Alaska and send down a large trough towards the US. This trough and the remnants of the cutoff low will be merging together to create a period of soaking rain on Monday.

Today’s GFS model valid for Monday shows a period of soaking rain, as a deep Atlantic and Gulf of Mexico fetch hit the area (PSU E-Wall).

The remnants of the cutoff low will provide plenty of Gulf of Mexico moisture with a deep SW flow in most of the atmosphere, but at the lower levels, there looks to be quite the SE low-level jet, from the Atlantic Ocean. This combination will help to create rainfall amounts in excess of 1″ for most of the area, with perhaps some 2″ amounts possible. Gusty winds and a rumble of thunder will also be possible.

Because of the pattern change and the large trough, even after the storm moves out, temperatures look to be running below average with a few scattered showers for most of next week.

In other words, enjoy the rest of today and this weekend.