Cool with chance of showers Sunday

25 Jan 2015 | Author: | No comments yet »

Cleveland’s weekend weather will begin quietly, but snow expected Sunday.

11:00 p.m. update: The GFS model is in and shares a lot in common with the NAM model. A potent winter storm is working its way up the East Coast on Friday, promising heavy rain, snow and the possibility of ice accumulation from freezing rain. No snow is expected Friday, but an Alberta clipper should arrive by Sunday afternoon. (Mark Duncan, Associated Press) CLEVELAND, Ohio — Forecasters say an Alberta clipper will arrive in Northeast Ohio by Sunday afternoon, but it will be preceded by a few uneventful weather days. The far northern and western areas from just north of Baltimore to Winchester have the best chance of seeing accumulating snow that could end up being heavy if everything comes together right.

It shows periods of snow continuing on Monday, with some additional accumulation possible – especially Monday afternoon and evening as the coastal storm intensifies before pulling away Monday night. Today (Saturday): The bulk of this storm is done, but it’s still spinning just off to our east during the early morning, so some impacts are likely to remain.

The precipitation should start as early as around 4 p.m. this afternoon around Charlottesville and then should rapidly spread northeastward across most of the area by around 6 p.m. this evening. North and west of D.C. faces the likely highest impact from any wintry weather tonight into tomorrow, while the Sunday night system could be a region-wide affair. The potential for a boom scenario in the D.C. area would result if a particularly heavy snow band develops at this point and persists for several hours.

These slick spots are most likely in our colder suburbs, especially from Loudoun County through the northern half of Montgomery County and to the northwest. The swath of heaviest potential snowfall stretches from the Appalachians of northern West Virginia and southeast Pennsylvania, across central Massachusetts and north into Maine. However, pockets of iciness are even possible closer to town 11:15 p.m. final update: If you’re longing for snow after all this rain and mixed precipitation, you probably don’t have to wait long. Tonight’s American models continue to show the likelihood of a strong clipper system dropping a swath of snow across the area starting Sunday night.

Having said that, because the ground is somewhat cold and precipitation will be coming in at night, caution should be used on roads this evening and overnight. Confidence: Medium Tonight: Rain or a sleet/rain mix wants to be the predominant story, but we do need to watch for the risk of an evening snow burst.

Even if that happens, temperatures might be marginal close in to the city at least, and we’d still change to rain and/or sleet by midnight most spots. You can see how far removed the very persistent band is as the storm pulls away below: 2:55 p.m. update: A winter storm watch is in effect for some of our far northwest suburbs, including northwest Montgomery, northwest Loudoun, and Frederick counties until 9 p.m. on Monday. South of Baltimore, the heavier snow should stay to the west of the immediate D.C. metro area – though snow or sleet seems likely to mix in at times.

If you’re well north or west, a wintry mix including snow, sleet and freezing rain may persist for a good chunk of the night resulting in some accumulation. The National Weather Service is calling for 4 to 6 inches of snow and up to 8 inches in elevations above 2,000 feet, beginning Sunday evening and continuing through early Monday afternoon. 2:05 p.m. Update: Given the complexity of the upcoming storm, the model disagreement, and the explosive scenario shown by the well-regarded European model (which by the way shows 12 inches or more from Philadelphia to Boston), you are going to see and hear a lot of different forecasts and opinions. Bottom line is forecast confidence is really low right now, and probably won’t increase much until late tonight or during the day tomorrow. 1:25 p.m.

For much of the region, precipitation should taper off during the daylight hours Saturday with just lingering light drizzle (most locations) or very light snow (colder locations to the north and west). Confidence: Low-Medium Tomorrow (Saturday): The heaviest activity may be out of here by sunrise or shortly thereafter, but a showery regime could last into midday or so.

This is similar to scenario 3 below, although suggests two somewhat distinct periods of accumulating snow — lighter accumulations Sunday night into early Monday morning, and heavier accumulations Monday night — with total accumulations in the 4-6″ (or more) range. Even those at 32 aren’t generally seeing much if any icing. 7 PM Dulles sounding is isothermal (constant temperature), 1 deg C, in the lowest 8,000 ft. With surface temps 1-3 deg C above freezing area-wide, and a south wind, it would seem that ice – from here on out – will be a diminishing proposition.

Locations north of New York City will likely endure the longest storm duration and the largest snowfall totals as the nor’easter deepens rapidly off the coast. Snow will begin after sunrise on Saturday, and wintry precipitation is likely to continue through at least the late afternoon, and possibly into the evening hours. Some remain even in NW D.C. several hours after the sleet stopped. 7:45 p.m. update: For the immediate metro area, there are signs the snow and sleet excitement is waning as precipitation shifts to more sleet and rain. The big takeaway is that the temperature is within half of a degree of freezing from the ground surface to a depth of almost 2,500 meters (8,000 feet) through the overnight hours. Lighten the precipitation a tad and the temperatures in that layer would probably be a little warmer, resulting in more rain and sleet instead of snow.

A similar storm track to Scenario 1 but the cold air erodes quickly and temperatures rise and stay above freezing for most areas except the western Maryland toward Garret County and adjacent parts of West Virginia. Snow develops late Sunday afternoon across the far western suburbs and then spreads east across the region producing typical clipper-like snows on the order of 1-4 inches. In such a scenario, the low tracks to our south but the upper-level trough remains a little too strung out to produce a quick transfer of energy to the coast, and the low deepens too far east to produce an intense banding. Confidence: Low Behind our storm system on Tuesday, we should be able to see a good deal of sunshine, with only periodic patches of cloudiness popping up at times.

The short range HRRR model shows temperatures aloft below, looking at a current panel and a forecast for 8 p.m. 850 mb (5,000 feet) temperatures are often used as a proxy for simple forecasting of snow vs something else. Bridges, sidewalks, and some streets may become slippery in places above freezing as well. 5:35 p.m. update: Mixed precipitation has pushed north to the Maryland/Pennsylvania border.

Here you can write a commentary on the recording "Cool with chance of showers Sunday".

* Required fields
All the reviews are moderated.
Twitter-news
Our partners
Follow us
Contact us
Our contacts

About this site