weathermedic

Good AM discussion out of OKX The overall synoptic picture into early next week continues to sharpen. At the surface, arctic high pressure slides east from the Great Lakes into the Northeast this weekend. Meanwhile, low pressure develops and tracks through the South before redeveloping off Cape Hatteras, passing near or just inside the 40N/70W benchmark into Monday. Aiding the potential for snowfall, an arctic air mass settles in ahead of the storm. 925 mb temps look to fall toward -20C or below on Saturday, with surface temperatures progged in the teens during the afternoon, setting up one of the coldest days in several years. This will allow snow to fall everywhere at the onset, which looks to develop rather quickly either very late Saturday night, or more likely Sunday morning around or after daybreak. Periods of heavy snow then appear likely late Sunday morning through the afternoon via the strong frontogenetic and thermal forcing aided by an anticyclonic upper jet to the north. Snowfall rates in this period likely eclipse 1 in/hr at times, perhaps closer to 2 in/hr. Given the cold air mass in place initially, SLRs start out on the higher side (15-18:1) at onset, gradually falling back toward 10:1 or lower along the coast by late afternoon as the mid levels warm. With guidance having adjusted to a closer to the coast surface low, the proximity introduces the possibility of enough warm air intrusion around 800 mb for the snow to mix with or change to sleet Sunday evening. Best chances for this are along the coast, including Long Island and NYC metro. Lower confidence in this occurring going north, with all snow still the most likely solution into the Lower Hudson Valley and Southern Connecticut. Freezing rain or drizzle also cannot be ruled out, though significant icing appears unlikely. As the coastal system deepens and lifts north and east into Monday, the boundary cools once again, and any wintry mix likely tapers as snow showers or flurries into late Monday morning or afternoon. Any additional accumulation is likely light. Forecast snowfall totals have decreased slightly along the coast. This is due to the increased potential for mixing as the warmer air aloft works in. It should be emphasized though the heaviest and steadiest precipitation is expected Sunday morning into early evening, with the bulk of snow accumulation occurring prior to any potential changeover. With QPF progged over an inch, areas that remain all snow should be able to yield double digit snowfall. The question becomes how much warm air is able to work in and force a changeover to sleet, cutting down snow totals. All said, still expecting a widespread 8 to 14 inches across the region, with localized amounts perhaps approaching a foot and a half where best banding sets up and ptype remains all snow. Greatest likelihood for this is across the interior. We remain just over 48 hours from event onset, so opted for no headline changes with this update. It appears likely warnings will be warranted for all areas later today or tonight, dependent on no significant deviations in forecast thought. Continue to monitor the forecast on what is increasingly likely to be a major winter storm with significant disruption to travel and daily life early next week.

That is only through 7pm Sunday

I remember in 1994 there was moderate to heavy rain for a good part of the day with temps in the low 20s

Also looks like the wind picks up towards the end of the precip as the low deepens

25 dropsondes reportedly dropped into the low off of Southern California for ingestion into the 0Z models

From Ryan Maue on X: We can partition the model output by how much "snow" will fall -- and then apply a "snow to liquid" ratio (SLR) which is typically 10:1 at temperatures around freezing. But this snow will be falling in frigid air 8°F to 18°F so SLR > 15:1 or 18:1 Do the math: 1.4" QPF x 18:1

Here is the Mt Holly AFD from this morning: KEY MESSAGE 3...There is an increasing potential for the area to be affected by an impactful winter storm late Saturday through Sunday, however quite a bit of uncertainty in the forecast details still remains. Signals in the upper level pattern by late week and the weekend becomes quite active between the northern and southern stream jets. The key elements embedded in these features are currently located over the Arctic and the Pacific Ocean, so it`ll likely take at least a couple more days for guidance to have a good handle on this system. However, almost all available guidance depicts an area of low pressure developing near Texas Friday before tracking eastward along the Gulf coast into Saturday. Beyond Saturday there still remains forecast uncertainty regarding the details of how this system will play out for the east coast. However, at this time most forecast guidance tracks the low north and east towards the North Carolina coast and then off to the north and east from here by the Sunday into Monday time frame. This track puts the mid Atlantic region on the northern side of the system with the main question then becoming just how close to us does the low track. There will be a very strong and broad arctic high to our north and some of our prior guidance had suggested this may be strong enough to suppress the system just south of the area. But over the past 12 to 24 hours there`s been a general trend northward in guidance suggesting the precipitation shield will make it into our area. In fact, snow probabilities of the NBM now show a 60-70% chance of 2+ inches of snow and a 40-60% chance of 6+ inches of snow for areas roughly along and south of the I-95 corridor with decreasing probabilities farther north. These probabilities are higher than with the prior forecast cycle. So while this system still is about 5 days out, the signal for a winter storm to impact at least parts of the area is higher than usual. The timing of this would be as early as very late day Saturday continuing through Sunday and potentially even lingering into Monday depending on the system`s speed. We will stress though that even with this trend in the guidance, most east coast snowstorms typically drop their heaviest snows in swaths 50 to 100 miles wide or less. And considering that the pieces of energy that will drive this storm are still thousands of miles away, that means it`s much too early to have much confidence on how much snow will fall at any given location. Users should keep a close eye on the forecast over the coming days.

Got a total of 1 inch here in Sheepshead Bay Brooklyn today. Had .8 yesterday and .26 of rain today

.26 of rain here so far. Very light snow now

Some flakes mixing in with the light rain now here in southern Brooklyn

Radar filling in over the northern half of NJ with northeast movement towards NYC

.75 inches of snow here at my station

34 and slushy accumulations on streets and sidewalks in southern Brooklyn

36 with light-moderate snow here in Sheepshead Bay

NWS going with 20% chance of snow on Sunday in their point and click forecast for NYC (Manhattan) Goes up to 30% in Brooklyn and through Nassau. Jumps up to 40% chance over eastern Suffolk.

Maybe graupel?

52 mph gust at LGA last hour

Wind advisories expanded into OKX forecast area: Northern Fairfield-Northern New Haven-Northern Middlesex-Northern New London-Southern Fairfield-Southern New Haven-Southern Middlesex-Southern New London-Western Passaic-Eastern Passaic- Hudson-Western Bergen-Eastern Bergen-Western Essex-Eastern Essex- Western Union-Eastern Union-Orange-Putnam-Rockland-Northern Westchester-Southern Westchester-New York (Manhattan)-Bronx- Richmond (Staten Island)-Kings (Brooklyn)-Northwest Suffolk- Northeast Suffolk-Southwest Suffolk-Southeast Suffolk-Northern Queens-Northern Nassau-Southern Queens-Southern Nassau- 1243 PM EST Mon Dec 29 2025 ...WIND ADVISORY IN EFFECT FROM 4 PM THIS AFTERNOON TO 6 PM EST TUESDAY... * WHAT...West winds 15 to 25 mph with gusts up to 50 mph expected. * WHERE...Portions of southern Connecticut, northeast New Jersey, and southeast New York. * WHEN...From 4 PM this afternoon to 6 PM EST Tuesday.

4.0 inches exactly at my station here in Sheepshead Bay Brooklyn.

Warnings up for Dutchess and Ulster for 5-8 inches

NYC Emergency Management Office just sent this out: New York City Emergency Plan Information:Plan: Winter Weather Emergency PlanStatus Change: ActivatedEffective As Of: 12-26-2025 08:00Conditions: Snow accumulation of 3 to 5 inches

But about 1/2 inch of salt on the roads!

Montauk Point Lighthouse Davis weather station network reported an 85mph gust. Don't know how high off the ground the sensor is mounted but still impressive.

Special Weather Statement National Weather Service New York NY 1028 AM EST Fri Dec 19 2025 CTZ005>012-NJZ002-004-006-103>108-NYZ067>075-078>081-176>179- 191900- Northern Fairfield-Northern New Haven-Northern Middlesex- Northern New London-Southern Fairfield-Southern New Haven- Southern Middlesex-Southern New London-Western Passaic- Eastern Passaic-Hudson-Western Bergen-Eastern Bergen- Western Essex-Eastern Essex-Western Union-Eastern Union-Orange- Putnam-Rockland-Northern Westchester-Southern Westchester- New York (Manhattan)-Bronx-Richmond (Staten Island)- Kings (Brooklyn)-Northwest Suffolk-Northeast Suffolk- Southwest Suffolk-Southeast Suffolk-Northern Queens- Northern Nassau-Southern Queens-Southern Nassau- 1028 AM EST Fri Dec 19 2025 A line of showers with gusty winds will be moving across the area late this morning into early afternoon. This will likely be the time when the strongest gusts of the day occur. Gusts will be mostly 40-55 mph, but some areas will see gusts around 60 mph. Gusts up to 70 mph will be possible across Long Island and coastal Connecticut.

1.17 inches so far at my station