Raw, wet, and chilly to begin the work week

Welcome to March, a transitional weather period. Average daily high temperatures begin the month in the mid-50s, climbing to the mid- and upper 60s by the end of the month. That change isn't a smooth one, with ups and downs in temperatures pretty much the norm. A perfect example is the plunge from Sunday's highs in the low 70s to today's (Monday's) forecast high near the 40º mark.

Another cold air damming (CAD) wedge is responsible for this particular rollercoaster. This graphic from the National Weather Service office in Sterling Virginia illustrates:

A thin layer of dense cold air at the surface is "wedged" across the Piedmont east of the mountains, forced southward by high pressure currently centered across New England. Warm moist air - being lighter and less dense -  is being pushed up and over the CAD wedge, creating clouds and precipitation. 

As of the most recent forecast model runs the precipitation from this setup will begin across Mecklenburg county as rain just after the lunch hour today. Although there could be a few cases of "fuzzy rain" with snowflakes mixing in, today's precipitation will be liquid instead of frozen. Rain will continue through the overnight hours, gradually tapering off Tuesday morning.

The wedge will slowly dissipate tomorrow. The official NWS forecast is for a mid-50s high temperature Tuesday afternoon. However, one forecast model which is particularly good at sniffing out CAD behavior indicates that the upper 40s may be all that can be expected tomorrow. Regardless, expect mostly cloudy skies until late tomorrow afternoon.

By Wednesday the temperature rollercoaster will be on the upswing. The latter part of the work week will see the 70s and perhaps the 80s(!) as warmer air reasserts itself across the region. 

Spring-like Sunday conditions, then wintry stuff(?) Monday

Welcome to meteorological spring! For weather and temperature accounting data that season runs from March 1st through May 31st, a bit different than the astronomical season that begins March 20th with the spring equinox, Regardless, today - Sunday - will feature a taste of spring under mostly sunny skies and with temperatures topping out in the upper 60s this afternoon.

A backdoor cold front will slide through Mecklenburg County before the dinner hour, pushed along by a strong high pressure center crossing the Great Lakes region. That will swap surface winds around out of the northeast, bringing a slight chance of a late day sprinkle. Behind this boundary a cold air damming scenario will set up. Here's one model's look at the dense cold air at the surface pushing down the Piedmont east of the Appalachians Monday evening:

A couple of weak upper air disturbances will then lift warm moist air up and over this thin surface layer, creating precipitation Monday that may well be in the form of "fuzzy rain", i.e. mixed rain and snow. Tomorrow will thus be gloomy and raw, with local thermometers struggling to make it up to the 40º mark. 

Tuesday then looks to begin wet and cloudy, but skies will begin clearing during the afternoon. Temperatures will begin the second day of the work week in the mid-30s before rising to near or just above 50º. The rest of the week? Plan on spring-like 70s for daily highs!

Finally, a spring-like weekend!

Lately, weekends have been punctuated by less-than-desirable weather. Last weekend was a perfect example, with the snowstorm turned nor'easter that dropped wintry precipitation across the area as shown on this summary graphic from NWS Wakefield:

This weekend, however, will bring much nicer conditions. Today - Friday - will bring afternoon highs in the low 50s under mostly cloudy skies and with lighter winds. The weekend days will then feature bonus weather to end February (Saturday) and begin March (Sunday). Both days will see sunny skies with temperatures bumping up into the mid-60s to the low 70s, ten to fifteen degrees above the average.

Enjoy the warmth! By Monday another cold air damming wedge will take charge, possibly resulting in another bout with wintry weather. More on that potential will come in Sunday's blogpost.

Clouds and showers will dominate the midweek period

One of the characteristics of an active weather pattern can be a dearth of sunshine as systems regularly roll across the country. Today - Wednesday - is an example, as clouds and a few intermittent showers replace the blustery and chilly sunshine of the past couple of days. The dry air in place at the surface is inhibiting most of the rain showing on radar, as the raindrops are evaporating before reaching the ground.

Counteracting the lack of the sun's warmth, southwesterly winds ahead of the next cold front are pumping warmer air into the area. This will enable temperatures to rise from morning lows in the mid-30s to afternoon highs in the mid- and upper 50s. By late afternoon the clouds should part enough to perhaps provide a colorful sunset (occurring at 6:04 p.m. in Clarksville).

Thursday will then be wet all day long. A low pressure center will form along the cold front as that boundary stalls just south of the state line. The moisture associated with this storm will arrive as all rain, with up to an inch of liquid expected:

Thursday morning temperatures will begin in the mid-40s. Depending on exactly where that cold front settles, there is some uncertainty as to how far local thermometers will rise tomorrow afternoon. The official forecast is for a high in the upper 50s, but that could be optimistic. Expect Thursday's high temperature to be closer to the 50º mark.

After a mostly cloudy Friday the weekend then looks to feature sunshine and daily highs in the 60s. That's the good news. The less-than-good-news is that more chilly air is on the way for the first half of next week.

A cool and blustery start to the week ahead

Bomb cyclone. That's a term being tossed around regarding the winter storm that is taking shape this morning. A low pressure center is taking shape at the surface near the Outer Banks of North Carolina. Meanwhile, a potent upper level low is spiraling over the Great Lakes region, on its way south and east. When the latter system meets up with the surface low the storm will rapidly intensify, supercharged with extra energy. The result will be a strong nor'easter:

Mecklenburg County will mostly escape the wrath of this system, while the northern Mid-Atlantic and New England states will not. Locally, today - Sunday - will feature cloudy skies, rain changing to snow late this afternoon, and temperatures not budging much from this morning's low 40s. Winds will gust up to 20 mph on the back side of the storm as it traverses northward off the East Coast.

The flakes will continue until just after midnight, but only light accumulations (perhaps up to an inch) will be on grassy surfaces. Flakes will melt on relatively warm road and sidewalk surfaces, and overnight temperatures only dropping to 30º won't overcome that residual warmth. As the precipitation ends skies will gradually clear, becoming partly sunny by dawn Monday.

Tomorrow and Tuesday will feel more like January than almost March, with afternoon highs only topping out in the mid- to upper 40s. Monday will also be blustery as the nor'easter intensifies. Northwesterly winds will gust over 25 mph much of tomorrow, providing a wind chill factor several degrees below the actual air temperatures. The rest of the work week looks to warm back to late February averages, with rain expected Thursday.

Blogposts may be intermittent this week, with Wednesday being the next one to expect.

Another weekend, another (weak) chance of seeing flakes?

No, despite what folks may have seen posted online by "social mediarologists" there is no chance of a major snowstorm this weekend. However, some flakes could fly late Sunday night. Meanwhile, there is other weather to talk about for Mecklenburg County.

On this Friday morning visibility is limited by a curtain of fog, with a Dense Fog Advisory in place until mid-morning. Temperatures and dew points (the true measure of humidity) have equalized at many locales, with fog being the result. A stationary boundary perched south of the VA/NC line will gradually lift northward today as a warm front.

Meanwhile, a cold front is crossing the Blue Ridge as this post is being penned. It is fostering a vigorous band of showers which will impact the county by mid-morning. The rain will scour away the fog, with perhaps a tenth of an inch of liquid expected. Following the cold front the skies will begin clearing after the lunch hour, and temperatures will climb into the low 70s(!) as drier air moves in.

That boundary will then stall over the southeastern U.S., and a wrinkle of low pressure will form along it. This will usher clouds back into the region tonight, accompanied by light showers most of Saturday. Tomorrow's temperatures will start out in the mid-40s before topping out near 60º for afternoon highs.

That low pressure center will then strengthen as it emerges off the Outer Banks Sunday morning. The latter weekend day will thus be wet and cool, with afternoon highs near the 50º mark. The exact track of this storm has had snow lovers in a tizzy, but this setup will feature colder air chasing after the available moisture. That's rarely a recipe for plentiful snowfall.

Here's the official NWS Wakefield forecast graphic for snow:

As stated previously there could be flakes Sunday night, but even the miniscule accumulations shown here will only be on grassy surfaces.

Happy Friday!

Scarce sunshine for the next few days

The current active weather pattern is rolling storm systems across the nation with regularity. The result for Mecklenburg County will be a decided lack of sunshine through the upcoming weekend, punctuated by periods of light rain. The good news is that temperatures look to remain at or above average until late in the weekend.

Today - Wednesday - will be mostly dry under cloudy skies. Gusty southwest winds ahead of a low pressure center over the Great Lakes will pump warm and moist air into the area. Thus, despite the lack of sunshine temperatures will top out in the upper 60s this afternoon following this morning's lows near the 50º mark. 

Precipitation will hold off until this evening, although there could be a few light showers late this afternoon. Thursday holds a greater chance of rain as a frontal boundary is forced southward (a "backdoor front") by high pressure located over New England. That front will usher in a cold air damming scenario, which is illustrated on this graphic:

Given the timing of that boundary's arrival in Mecklenburg County Thursday's high temperature may well occur during the morning hours, with thermometer readings dropping during the afternoon. And, given the uncertainties associated with these low level cool air wedges, tomorrow's forecast high in the mid-60s could be optimistic. 

The weekend weather looks mostly cloudy and showery, with temperatures by Sunday likely to drop below average again. Another lobe of cold air will be pushed across the East Coast as the jet stream sags south once again. It won't be Arctic level frigid, but early next week looks cooler than late February should be.