NAM – Weather 360

Uncertainty Remains as Major Weekend Storm Nears

January 16, 2019Posted in Major Storm, Weather 360, WinterTagged Extreme Cold, Freezing Rain, GFS, High Winds, Ice, Mid Atlantic, NAM, New England, New York City, New York Metro Area, Power Outages, rain, Sleet, snow, Snow StormLeave a comment

Aside from several inches in November, it has been ten months since there has been significant snowfall seen in the New York City Metropolitan Area. This is now expected to change as soon as this weekend, as a significant winter weather event has begun to move east.

gfsfv3 1 16 19 102hr mslp — The evening run of the FV3 GFS computer model on January 16, 2019. Any slight shift to the east or south with this storm could mean extremely high snow totals closer to, or even south of, I-95. (Image courtesy tropicaltidbits.com)

Snow will quickly develop and intensify as it moves into the Tri-State Area late Saturday evening or early Sunday morning, bringing with it rapid accumulations on most surfaces. However, the position of the storm will dictate if and when many locations will see a changeover to sleet, ice, or rain.

At the moment, it appears that locations north of the city and I-95 will experience this transition as early as 9 am Sunday, allowing for potentially significant ice accretions on many surfaces by noon Sunday.

Whether or not the precipitation remains frozen or becomes rain during the day, snow and ice will redevelop by the afternoon as temperatures drop and winds increase Sunday night. It is also important to note that, regardless of the direct impacts of the storm, temperatures will fall to near below zero throughout the Mid Atlantic and New England by early Monday morning. This rapid refreezing could mean any liquid precipitation that falls may become ice on roads, trees, and power lines quickly after the storm exits the area.

nam12km 1 16 19 84hr — The evening run of the NAM 12km computer model on January 16, 2019. This particular run suggests a delayed transition from snow to ice or rain around NYC, meaning snow accumulations could run much higher than currently expected. (Image courtesy tropicaltidbits.com)

Due to the uncertain nature of the this storm, Weather 360 is currently forecasting anywhere between 4 and 12+ inches north of I-95, with anywhere between 3 and 8+ inches to its east and south. Forecasts will be refined in the coming days as the center of the storm develops, but for now, be prepared for a storm that could knock out power, make travel dangerous for an extended period of time, and dump a significant amount of snow, sleet, ice, and rain.

Massive Hurricane Florence to Slam the Carolinas

September 12, 2018Posted in Major Storm, Tropical Cyclones, Weather 360Tagged Category 3, Category 4 Hurricane, Hurricane, Hurricane Florence, Hurricane Preparedness, Hurricane Warnings, Hurricane Watches, Major Hurricane, NAM, North Carolina, South CarolinaLeave a comment

Hurricane Florence, now a major category 3 hurricane with winds in excess of 115 mph, is expected to restrengthen as it makes its way towards the coast. Storm Surge and Hurricane Warnings are in effect from Myrtle Beach, South Carolina, to the northern Outer Banks in North Carolina, with Hurricane Watches extending as far south as Charleston.

Florence NHC Track 09 12 18.png — Official NHC track and wind field assessment as of 8:00 PM ET on September 12, 2018.

Although the effects of Hurricane Florence will begin to impact the Carolinas starting tomorrow afternoon, strong winds and heavy rain will continue to lash the region until the end of the weekend due to the storm’s unusual path.

Florence NAM 3KM Future Radar 09 12 18.png — This is the 18z 9/12/18 run of the NAM 3km computer model depicting an extremely intense Hurricane Florence approaching the Wilmington, NC area.

For the past several days, computer model guidance has shifted to suggesting that Hurricane Florence will begin to slow down and proceed to parallel the coastline come Friday evening. The storm’s unusual path will force extremely dangerous winds and storm surge across a swath of land extending from the Outer Banks to South Carolina, placing millions under the threat of life-threatening conditions. Unfortunately, these conditions will only be compounded and exacerbated by the upwards of 3 feet of rain forecasted to fall in some areas.

The National Hurricane Center is forecasting winds to exceed 120 mph upon Hurricane Florence’s arrival near the coastline, with a storm surge exceeding 9-13 feet in some locations, making this storm extremely dangerous for those in its path.

If you have been ordered or asked to evacuate, please heed these orders immediately before it becomes too late to do so. All preparations for this storm should be completed immediately.

For more information, please consult the National Hurricane Center at http://www.nhc.noaa.gov or your local emergency management office.

Tropical Storm Erika may impact Southeast Coast, but will it make it there?

August 28, 2015August 28, 2015Posted in Tropical CyclonesTagged Atlantic Hurricane Season, computer models, Cuba, east coast, ECMWF, Euro, Florida, GFDL, GFS, Hispaniola, Hurricane, Hurricane Hunters, Hurricane Season 2015, Invest 98L, Moutains, NAM, nhc, Puerto Rico, SFWMD, Southeastern United States, The Bahamas, The Turks and Caicos, The Virgin Islands, Tropical Storm Erika, Weather 360Leave a comment

As of 11:30 AM EDT/AST

Tropical Storm Erika has sustained winds of about 50 MPH with gusts upwards of 60 MPH. The storm is moving west-northwestward at the moment over the Dominican Republic. Tropical Storm Warnings are still in effect for Puerto Rico, the Virgin Islands, parts of The Turks and Caicos along with The Bahamas, and all of Hispaniola. Hurricane Hunter Aircraft are in the storm.

The Track

This image is made public by the South Florida Water Management District (.gov)

The track seems to be locking in and narrowing down, well, at least compared to yesterday at this time, but nonetheless, the expected track and intensity are still at a state of ‘low confidence’ as mentioned by the NHC in their latest Tropical Forecast Discussion. The general trend though, is that the storm will pass over Hispaniola over the next day, then turn northward toward Florida, then possibly re curving, to go back over the Atlantic and to head up the East Coast. For those in Florida or along the Southeast Coast of the United States, please continue to monitor the situation, as the cone of uncertainty continues to include the possibility of a major storm impacting the Eastern Seaboard.

Intensity, Will She Survive?

Who knows, Erika is seeming to have a mind of her own as she has not followed the official NHC track whatsoever over the last several days. Although this is true, over the past hour or two Erika has seemed to finally get her act together (or the NHC for that matter) in determining the track, because Erika’s center of circulation along with her discombobulated thunderstorms have seemingly begun to shift to the northwest. Erika is expected to strengthen at least to a higher-grade Tropical Storm by the NHC, and by a very consistent computer model, the GFDL, a major Category Four storm off of the Southeast Coast. But what is the driving force behind its intensity? Mountains…

Believe it or not, the only difference in the computer models is if Erika will be torn up enough by the mountains for it not to reform to a well-defined system. According to the NHC, Erika will be so torn up by Hispaniola’s mountains, that it will not be able to strengthen too significantly before potential impact with Florida. This whereas the GFDL computer model along with some others, suggest a less torn-up version of Erika and strengthen her rapidly, causing her to not impact Florida for too long and move her up the US East Coast quickly as a large Major Hurricane (as of 6 UTC.)

Official Alerts:

Tropical Storm Warnings are in effect for The Virgin Islands, Puerto Rico, all of Hispaniola, The Turks and Caicos, The Bahamas.

Tropical Storm Watches are in effect for parts of Cuba, and the northwest portions of The Bahamas.

Weather 360 3.A.S.: Tropical Storm Warning areas are under a Level I Emergency, Locations under Tropical Storm Watches are under a Level II Alert, and a Level III, Be Aware, statement is for the Entire East Coast from Florida to Massachussetts.

Weather 360 will continue to keep you updated on the progress of Erika.